-, /*. ,*\ A AGIIC- DEPT, i v V 1 \ ll^Si vA^^aV ~> <\ , fc' A A .* A-A ; ^ ;$^ A AAA^Ar\A^lte^k^^?) , mjffm^i^Mm^ \LW ",/?x y i n . A^ - jinnHW* G P * > \WQ . : : : ' J VrvLV V "nfcB.f I; A A - - f ., A r " ' DEPARTMENT OF THE INTERIOR, CENSUS OFFICE. FRA-NCIS A.. "WALKER, Superintendent, Appointed April 1, 1879 ; resigned November 3, 1881. CHAS. "W. SEAXON, Superintendent, Appointed November 4, 1881. REPORT ON THE MANUFACTUEE OF GLASS. BY cros. ID. SPECIAL AGENT. WASHINGTON: GOVERNMENT PRINTING OFFICE. 1884. AGiiC. DEPT. TABLE OF CONTENTS. LETTER OF TRANSMITTAL ii CHAPTER I. STATISTICS -- 1-18 Scope of the report 1 Classification of glass in the tables 1 Summary of statistics for 1880 1 Comparison with previous censuses . 2 Works idle in the census year 2 Works building in the census year 3 Establishments in which glass was made in the census year 3 Capital ... 3 Furnaces - - 3 The plant of factories 4 Employe's 5 Wages paid , 6 Intervals of payment 8 Methods of payment 8 Product 9 Materials 9 Relative productive rank of the states " 9 Production of plate-glass 10 Production of window-glass 10 Production of glassware 10 Production of green glass 11 Localities in which glass was produced 11 Table I. The plate-glass works of the United States at the census of 1880 11 Table II. The window-glass works of the United States at the census of 1880 12 Table III. The glassware works of the United States at the census of 1880. -. 12 Table IV. The green-glass works of the United States at the census of 1880 12 Table V. Glass works idle and building in the United States at the census of 1880 13 Table VI. Consolidated statistics of all the glass works of the United States at the census of 1880, by states lo Table VII. Consolidated statistics of all the glass works of the United States at the census of 1880, by states and counties. 15-1? Table VIII. Consolidated statistics of the materials used iu the manufacture of glass, as reported at the census of 1880 ... 18 CHAPTER n. QL4S8: ITS COMPOSITION, CLASSIFICATION, AND PROPERTIES 19-23 Difficulty of definition 19 Glass, chemical and commercial 19 Chief constituents 19 Variability of composition 19 Approximate composition 19 Difficulty of classification chemically 19 Difficulty of classification commercially 20 Classification _ 20 1. Plate-glass 20 2. Window-glass 20 3. Flint glass 20 4. Green glass 21 Specific gravity 21 Conductivity and tension 21 Tensile and crushing strength 21 Devitrification 22 Devitrification in its relation to manipulation - .' 22 Other properties 22 Extent of the uses of glass 22 Analysis of glass . 22,23 1031 iv TABLE OF CONTENTS. CHAPTER III. Page. SAND 24-30 Different proportions of silica in glass 24 Silica in different kinds of glass 24 Hardness 24 Forms of silica used 24 Uses of the different grades 24 Impurities and their removal 24 Use of arsenic 25 Tests of sand 25 Analysis and color not always indicative of the quality of sand 25 Mode of occurrence of sand 25 Sea or river sand 25 Importance of good sand 25 Sand from the river Bolus 25 Other river and soa sands 26 Early use of flkit and quartz 26 Superiority of American sand 26 English sand 26 Sand for English plate-, window-, and flint-glass 27 Sand for bottle-glass 27 . . French sand 27 Belgian sand - 27 German sand .' 27 Best German sands 27 Use of alkaline rocks for bottlo-glass 28 Austrian sand 28 Sand for common Austrian glass 28 Swedish sand 28 Quality of American sand 28 New England sand 29 New Jersey sand 29 Maryland sand 29 Sand for the Pittsburgh and Wheeling glass houses 29 Illinois sand 29 Missouri sand : 29 Extent and locality of other American sands 29 Analysis of glass sand 29,30 CHAPTER IV. ALKALIES AND OTHER MATERIALS 30-34 Chief bases used in glass-making 30 Ancient glass a soda glass and perishable v 30 Sources of supply of soda for ancient glass houses 30 Modern soirees of soda 31 Loblanc's discovery of soda-ash 31 Use of salt-cake 31 Source of supply of soda 31 The ammonia process 31 Manufacture of soda-ash and salt-cake in the United States 32 Use of common salt 32 Nitrate of soda 32 Potash 32 Lime 32 Use of lime a modern discovery , 32 Sources of supply 33 Lead 33 Lead glass, where made .". ,. 33 Other ingredients 33 CHAPTER V. GLASS FURNACKS AND POTS , 34-41 Early furnaces and glass houses 34 Furnaces in Agricola's time 34 Modern furnaces 35 Fuel used 36 Gas furnaces 36 The Siemens' furnace 36 Use of Siemens' furnaces in the United States 'H 1032 TABLE OF CONTENTS. GLASS FURNACES AND POTS Continued. Compartment or tank furnaces -- Pot-clay Composition of pot-clay Manufacture of pots - - The setting of the pots - 41 Life of pots 41 Size of pots - - - 41 Shape of pots 41 CHAPTEE VI. MIXING, MELTING, FINING, AND FAULTS 41-45 Influences that determine the character of glass 41 Constituents of the batch --- Proportion of materials nsed for plate-glass 42 Proportion of materials nsed in window-glass - 42 Proportion of materials nsed for flint (lead) glass 42 Proportion of materials nsed for flint (lime) glass 42 Proportion of materials nsed for bottle-glass 43 Mixing the batch - -- 43 Fritting 43 Charging - - - - - 43 Melting 43 Fusion and fining - -- 43 Time required to melt and fine .- - - 44 Cold stoking - 44 Loss in melting .. - - 44 Faults in the metal - - --- 44 CHAPTER vn. GLASS-WORKING -- --- 45-55 Methods of glass-working - Plate-glass 45 Casting and annealing - 45 Rough plate - Grinding, smoothing, and polishing Rolled plate 46 Optical glass Strass - 46 Pressed glass 47 Improvements in the pressing process Mold-marks Molding articles with lateral designs - - 47 Molding curved hollow articles, lamps, goblets, and taper articles Molding months, necks, etc .- - Handles - Lamp bodies with feet sad screw coupling Lamps with metallic pegs or collars - Insulators 48 Balls - Movable-bottom molds - - 48 Battery jars - 48 Molds for flaring articles 49. Molding articles with bulging bodies - Molding articles with openings - - - 49 Spring snaps for lire-polishing .--- 49 Cooling heated molds by air-blast - 49 Application of steam to glass-pressing 49 Application of compressed air 49 Inclosed air- bubbles - - - 50 Blowing 50 Window-glass - 50 Flattening 50 Defects of window-glass 50 Size of window-glass 51 Blown and patent plate 51 Blowing flint ware - 51 Flint-glass cutting, engraving, and etching Blowing in molds - 51 1033 vi TABLE OF CONTENTS. GLASS-WORKING Continued. Fashioning art-glass . 52 The Portland vase 52 Tempered, hardened, or toughened glass 52 Bastie's tempered glass 53 Difficulties of the process.... 53 Siemens' tempered glass 53 Tests of the Siemens' glass 54 Uses of Siemens' glass 54 Cost of Siemens' glass 54 Glass from blast-furnace slag 54 Relative composition of glass and slag,.... 54 Additions to slag in the manufacture of glass 55 Use of hot slag 55 Color of slag glass 55 CHAPTER VHI. HISTORY OF SOME PROCESSES OF GLASS-MAKING 56-66 Vases, cups, and other hollow ware - 5T Lead glass 57 The use of molds...... 57 Pressed glass 58 Ancient pressed glass . ....... 58 History of the invention 58 CHAPTER IX. ANCIENT GLASS 59-64 Discovery of glass.... ..... 59 Probable method of discovery 59 Egyptian glass 59 Processes of Egyptian glass houses and character of the glass.... 60 Composition of Egyptian glass 60 Phoenician glass 60 Character of Phoenician glass and processes employed 61 Late Phoenician glass manufacture '. 61 Glass-making in the other ancient monarchies 61 Assyriam glass 61 Greek glass 61 Carthaginian glass 61 Etruscan glass 61 Introduction of glass-making into Rome 62 Amount and variety of the production of Roman glass houses 62 Later glass-making 62 Byzantine glass 62 Early glass-making in other countries 63 Glass in France 68 Spain 63 Germany 63 British islands 64 Persia 64 China 64 India 64 CHAPTER X. MODERN GLASS 64-69 Modern glass-making dates from Venice 64 Influence of barbarians upon glass-making 65 Revival of art influenced glass-making 66 Early Venetian glass-making 65 Extent of the industry at Venice 65 Condition and restriction of workmen 65 Glass in the dark ages .*. 66 France 66 Spain 66 Germany 6" 1 Bohemia 6" The Low Countries 66 British islands 68 Influence of Venice on England 63 Russia 68 1034 TABLE OF CONTENTS. vii CHAPTER XI. *. THE PRESENT CONDITION OF GLASS-MAKING IN EUROPE 69-77 Chief glass-making countries of Europe 69 Each country has a specialty - ................... 69 England's specialties ........... .... ... 69 France's specialties 69 Belgium's specialty 69 Germany's specialty 76 Austria-Hungary's specialties 70 Venetian glass 70 Glass in other European countries 70 Plate-glass factories in Europe 70 Production of plate-glass 70 PlaU-glass 71 Prices of plate-glass in Europe 71 Window-glass in Europe 71 Flint- and bottle-glass 72 Manufacture of glass in Great Britain . ............ 72 Chief localities 72 Decline of the English glass industry 72 Imports of glass 72 Eiports of glass .......... 72 Manufacture of glass in France 73 Manufacture of glass in Belgium 73 Manufacture of glass in Germany ............. 74 Furnaces and fuel 74 Manufacture of glass in Austria-Hungary 74 Manufacture of glass in Italy 76 Manufacture of glass in Russia 76 Manufacture of glass in Sweden 76 Manufacture of glass in Norway 77 Manufacture of glass in Spain ..................... 77 Glass in Holland 77 Glass in Portugal 77 CHAPTER XII. HISTORY OF GLASS-MAKING LN THE UNITED STATES . 77-101 Glass-making in Virginia and West Virginia . 77 Glass-making in Pennsylvania 79 Glass-making in Massachusetts ................ 88 Glass-making in New Hampshire 91 Glass-making in New York 93 Glass-making in Connecticut 94 Glass-making in Maryland 95 Glass-making in New Jersey 96 Glass-making in Ohio 97 Glass-making in Missouri 97 Glass-making in other states 97 History of the manufacture of plate-glass in the United States 98 Imports of glass into the United States 99 Table showing imports of glass into the United States in the yean 1676 to 1880 100, 101 t LETTER OF TRANSMITTAL. PITTSBURGH, PA., March 21, 1883. Hon. C. W. SEATON, Superintendent of Census. SIR : I have the honor to transmit herewith my final report on the manufacture of glass. Referring to my preliminary report, published in Census Bulletin No. 118, under date of March 30, 1881, I beg so say that further investigation disclosed the fact that the returns received up to that time were somewhat imperfect, and the statistics given in this report have been amended in accordance with the later returns received. Most of the glass-makers of the country appreciated the importance of a full and complete report, many of them not only forwarding their reports promptly and with full details, but lending me every assistance in their power in completing the history of glass in this country, which is herewith attached. In undertaking the collection of these returns it was discovered that no directory of the glass works of the United States existed. While attempts had been made in recent years to prepare such a directory, they had been abandoned by those undertaking the work, and it was believed to be impossible to make a complete directory. However, with the assistance of some gentlemen well informed with the glass industry, such a directory, though imperfect, was prepared. Copies were sent to every glass works in the United States and to every one who was supposed to have any information regarding glass works, and as a result of this a directory, believed to be correct at its date, was prepared. Schedules were sent out to the names in this list, and the result is the present report. This report covers the statistics of those establishments only that made glass from the sand, or works having furnaces and pots in which the glass was melted and made into the various forms of plate- and window-glass, glassware, and green glass. It does not include the statistics of any staining, cutting, engraving, drawing, or spinning glass, or any of the other processes of reworking glass, except in the case of establishments that cut and engrave in connection with the manufacture of the glass from the sand. In a word, the report covers the manufacture, and not the reworking, of gl In addition to the statistics and history of glass-making in this country, such information as could be obtained regarding the statistics of this industry in Europe and a short sketch of its history, both ancient and modern, are appended. For the purpose of completeness I have also added some statements regarding the classification of glass, its properties, the materials used, furnaces and pots employed, and the various modes of glass-making, with some quite fall statements regarding tempered and slag glass. Particular attention has also been paid to statements showing the state of the art during the census year. While every i>oiiit has not been covered indeed it was not deemed wise to consider to any extent forms or varieties of glass other than the four kinds particularly reported upon it is believed that the report will show with reasonable fullness the condition of glass-making at the close of the census year. It seems hardly necessary to state that it is impossible to gather from the tables given in this report any .statement, even an approximate one, of the amount of profit made by the manufacturers of glass in the census year. The tables show only the value of materials and wages and the cost of product. Materials and wages added 1037 LETTER OF TRANSMITTAL. together and subtracted from product will not give profit, as, in addition to materials and wages, there is iii the cost of an article a large number of contingent expenses, such as rent, insurance, taxes, interest, discount, expense of selling, office expenses, advertising, traveling, etc., all of which must be added to the value of materials and wages before the difference between this sum and the selling price of the product will show the profit. In forwarding this report I desire to express my great obligations to the large number of gentlemen in various parts of this and other countries who have so kindly assisted me in the preparation of this report. It is impossible to name them all, but special thanks are due to Mr. L. Lobmeyer, of Vienna, Austria ; Mr. Julius Fahdt, of Dresden, Germany ; Mr. Henry Chance and Mr. Thomas Webb, of England ; Hon. John F. Bodine, of Williamstown, New Jersey ; Hon. W. 0. De Pauw, of New Albany, Indiana ; Mr. J. K. Cummings, of Saint Louis, Missouri ; Mr. Charles Colne", formerly of Washington, District of Columbia, who reported on glass for the Paris Exposition ; Mr. Isaac Craig and Mr. James B. Lyou, of Pittsburgh, Pennsylvania; and very especially to Mr. Thomas Gaffield, of Boston, to whose intelligent assistance and ready and free loan of books this report is indebted for much of its exactness and fullness. I also have made free use of a number of works on glass. In important quotations credit is given in the text, but in many cases it has not been deemed necessary, and I desire to acknowledge here my indebtedness to the Encyclopaedia Britannica, Pellatt's Curiosities of Glass Making, Nesbitt's Glass, Bontemp's Guide du Verrier, Lardner's Cabinet Cyclopedia, Jarves' Reminiscences of Glass Making, Blancourt's Art of Glass, Sauzay's Wonders of Glass Making in All Ages, the several pamphlets of Mr. Chance referred to in the text, Gaffield's Action of Sunlight on Glass, and Glass in the Old World, by M. A. Wallace-Dunlop, and for the history, in this country especially, to Bishop's History of American Manufactures. I should also fail in what was justly their due did I not acknowledge my indebtedness to Miss C. V. Young and Mr. S. C. Armstrong, the chief assistants in my office, to whose patient endeavors -rod constant care I am under so many obligations. Very respectfully, JOS. D. WEEKS, 1088 Special Agent. CHAPTER I. STATISTICS. SCOPE OF THE REPORT. The investigations which form the basis of this report were confined exclusively to those works which manufacture glass from the crude material or make the "metal", as it is termed, and do not include any statistics of those establishments in which manufactured glass is a raw material ; or, in other words, this report only covers establishments in which glass is made, not those in which it is reworked, and does not, therefore, include statistics of manufactories of painted or stained glass, mirrors, chemists' ware, etc. In cases, however, where the glass is reworked in the same establishment in which it is made, as where rough plate is polished or glassware is engraved or decorated, the tables include the statistics of such reworking, it being regarded as only a part of the manufacture of glass in these works, or as having such a close relation with its manufacture as to make it practically impossible to separate the statistics of the crude from the reworked glass. CLASSIFICATION OF GLASS IN THE TABLES. The classification adopted in the collection of the statistics is not to be regarded as a complete classification of glass, but as one made necessary by the conditions of its manufacture in this country. This classification is as follows : I. Plate-glass factories, including those making rough, ribbed, or polished plate for window-glass, mirrors, skylights, partitions, etc. This class also includes rolled cathedral plate. II. Window-glass factories, including those manufacturing cylinder or sheet window-glass. III. Glassware factories, including those manufacturing flint (lead or lime) glass, both blown and pressed, lamp- chimneys, and flint druggists' and chemists' ware. IV. Green-glass factories, including those producing green, black, amber, etc., bottles, fruit-jars, carboys, demijohns, and other hollow ware, and green druggists' ware. If it had been possible to make a still farther subdivision of these classes, it would have been done; but after very earnest efforts it was found impracticable, and the attempt was abandoned. Under each of these classes three tabulations have been made. A. Including all establishments in existence in the census year, whether active, idle, or building. B. Including all furnaces that were idle during the entire census year. All the furnaces in this table are included in Table V. The amount of capital given, however, is only that of factories no part of which was in operation daring the census year. If a glass works having two furnaces run one, the other being idle, the latter would appear in this table as an idle furnace, and no capital would be set against it. C. Including all furnaces that were building and were not completed during the census year. The amount of capital given in this table is that of such establishments as are entirely new, and includes no statement of capital invested in such new furnaces as are additions to old works. SUMMARY OF STATISTICS FOR 1880. The complete statistical results of the census of 1880 will be found in the accompanying tables. For convenience of reference, and to give a connected statement of the results of the present census, as also to compare the same as far as possible with those of previous censuses, these results have been summarized. The condensed aggregate statements for all classes of glass included in this report are as follows : Tetal number of establishments 211 Total capital invested $19,844,699 Total number of furnaces 348 Total number of pots in same 2,982 Males above 16 years 17,778 Females above 15 years 741 Children and youths 5,658 24,177 Total amount paid in wages daring the year $9, 144,100 Total value of materials 8,028,621 Total value of product 21,154,571 1039 MANUFACTURE OF GLASS. COMPARISON WITH PEEVIOUS CENSUSES. It is impossible to make a comparison between the results given above and those for the earlier censuses. The classification differs materially from that adopted in the present investigation, so that in any event it would be impracticable to make a comparison by classes. In addition to this, however, in the statistics of glass in previous censuses there are in some cases gross omissions, (a) while in others the statistics of glass-cutting and decorating establishments are summarized with those making the metal, so that any comparison would be of but little value. It is possible, however, to make an approximate comparison of the aggregate of all classes between the present ' Teasers 158 1 00 to 2 36 1 74 5 1 50 to 3 15 1 83 Lime sifters 34 1 00 to 2 16f 1 70 5 1 00 to 1 50 1 23 Mixers 65 1 00 to 3 00 1 72 5 00 to 3 00 2 40 Batch wheelers or flllers-in , 55 1 00 to 2 00 1 75 2 1 1J to 9 00 1 56 Coal wheelers 46 96 to 2 25 1 63 2 1 00 to 1 46 I 23 Flatteners 109 2 50 to 5 77 3 82 6 1 75 to 1 80 1 78 Layers-out 67 77 to 2 25 1 80 2 o (iQ to 2 50 2 25 Layers-in 73 77 to 2 33J 1 61 Clerks 7 1 88 Leer tenders 71 96 to 2 26 1 64 1 00 2 00 Koller-boys : 4 2 00 2 00 16 years and upward 70 38 to 1 50 78 1 4 00 4 00 Under 16 years 22 75 to 1 00 88 2 1 1S 1 121 Pot makers 36 1 54 to 5 00 9 96 2 1 25 1 9 5 Clay trampers . 89 1 00 to 2 00 1 25 Boss cutters 22 2 88 to 7 00 4 21 1 5 00 5 00 1044 MANUFACTURE OF GLASS. RANGE AND AVERAGE RATES OF DAILY WAGES IN THE MANUFACTURE OF GREEN GLASS. Classes. If amber. Range. Average. Classes. Number. Range. Average. 21 $2 00 to $6 73 $4 74 32 $1 25 to $7 25 $3 33 21 3 00 to 8 00 4 86 Fillers-iii 61 1 00 to 2 00 1 51 515 2 65 to 5 50 3 94 30 1 00 to 2 25 1 46 163 2 50 to 4 50 3 38 26 1 00 to 2 00 1 36 10 2 90 to 5 00 3 78 Teasers 66 1 00 to 4 17 3 3 30 to 10 00 5 53 45 1 00 to 2 50 32 3 00 to 3 25 3 3 10 50 to 2 00 1 29 62 58J to 2 00 1 27 326 54 to 1 50 97 16 1 50 to 4 00 2 61 17 75 75 26 1 00 to 2 00 1 36 41 1 00 to 1 50 121 32 to 1 25 42 29 38 to 88 51 35 83| to 5 00 1 30 3 60 60 63 45 to 4 50 2 73 22 1 16f to 3 50 2 02 4 50 50 31 75 to 2 00 1 06 182 38 to 73 59 10 1 00 301 38 to 83 54 Packers 119 83$ to 2 25 1 37 Laying-up boys : 150 50 to 1 50 96 26 50 to 1 00 79 RANGE AND AVERAGE RATES OF DAILY WAGES IN THE MANUFACTURE OF PLATE-GLASS. 13 $2 00 to $3 85 $3 39 MlTAfa 13 $1 25 to $2 00 *1 1A 7 1 25 to 2 00 1 76 | 2 31 to 3 33 2 94 11 1 15 to 2 50 1 95 4 1 67 to 2 00 1 84 12 1 15 to 1 80 1 53 Cutters ' 16 2 00 to 3 08 2 54 8 1 15 to 1 83 150 12 1 35 to 2 33 1 78 58 1 15 to 1 83 1 39 23 2 39 Blacksmiths 8 1 73 to 4 00 2 87 55 1 67 to 3 00 2 18 10 1 25 to 1 80 1 57 6 50 50 16 1 25 to 3 00 2 41 13 1 25 to 2 25 1 91 52 2 00 to 2 29 2 06 9 2 00 to 3 00 2 54 3 50 50 1 3 85 3 85 13 75 75 13 1 00 to 1 33 1 14 4 50 50 10 1 50 1 50 Mill men 4 1 67 to 1 75 1 71 65 2 00 to 3 13 2 49 5 1 CO to 1 50 1 31 6 50 50 RANGE AND AVERAGE RATES OF DAILY WAGES IN THE MANUFACTURE OF GLASSWARE. 52 $3 00 to $8 11 $4 46 I Cutters : 306 2 00 to 5 00 3 53 223 $1 35 to $4 16$ o 29 Finishers : 563 76 to 6 00 3 55 Females 15 years and upward 7 33 50 1 66} to 4 00 50 2 58 134 76 to 80 79 120 1 50 to 6 00 3M Machinists * 30 1 50 to 6 50 2 30 890 67 to 3 50 1 93 135 1 33^ to 2 66} 1 76 6 55 to 1 50 1 3t 166 1 50 to 2 66} 2 11 Pot fillers 56 1 00 to 2 50 1 67 338 42 to 1 88 87 41 1 16} to 3 334 2 35 543 4 to 1 00 78 74 1 00 to 2 50 43 Cleaning-off boys : 192 50 to 1 35 82 Packers : 340 60 to 4 00 1 72 414 50 to 1 00 64 19 45 to 65 53 3 80 19 50 to 2 33J 98 12 50 to 6} 58 103 iUO 1 00 to 2 50 1 72 t'air_ving-in boys: 156 48 to 1 20 62 Laborers : 573 1 00 to 2 00 1 35 762 33J to 80 56 67 to 83 69 Mnld-holders: 132 50 to 75 S3 Females 15 years and upward 82 9 60 to 75 50 to 67 67 61 285 45 to 1 00 6 54 1 16} to 3 00 2 15 1 147 1 66} to 5 00 3 47 * The machinist receiving highest rate is probably a mold maker. 1045 8 MANUFACTURE OF GLASS. INTERVALS OF PAYMENT. In the annexed table will be found a statement showing the intervals of payment at the different glass works in the United States so far as returns have been received. In connection with each interval of payment is also given the number of employe's so paid : Kind of glass. WEEKLY. KVEKY TWO WEKK8. MONTHLY. ON APPLICATION. NO STATEMENT. Number of works. Number of employe's. Number of works. Number of employes. Number of works. Number of employe's. Number of works. Number of employe's. Number of works. Number of employe's. . . 2 37 47 28 513 2,575 7,023 4,033 4 12 1 12 443 919 130 1,423 2 28 4 100 5,419 745 3 178 4 15 10 118 68 194 2 296 Total 114 14, 144 34 6,264 29 2,915 5 474 29 380 The frequency with which the workmen are paid is a matter of considerable importance, and determines in some degree the value of wages. When workmen are paid once a year, as they were at one time in New England, being allowed to take goods from the store in the meantime and have the same charged to their account, but being compelled to pay interest on any cash advanced, it is evident that such intervals of payment would not make the purchasing power of their wages as great as though the employe" was paid weekly or every two weeks. In some of the occupations about a glass works where the men are paid by the piece, as in window-glass blowing, owing to the peculiar character of the business it is almost impossible to ascertain at the end of each week or each two weeks what amount of money is due to the blower or flattener, they being paid in accordance with the quality of the glass produced, as this can only be ascertained when the glass has been flattened and cut, or at least inspected. This sometimes takes weeks, especially in dull seasons. It is therefore customary in these works to advance to men what is termed " market money", equaling a certain amount a week, and to have final settlements at the end of the "fire". In the window-glass report, therefore, it will'be understood that most of the skilled workmen, such as the blowers, gatherers, cutters, and flatteners, are paid weekly or every two weeks on account, and full settlements are had at the end of the "fire", generally in June. This is also true in some few cases in glassware manufactories, and to a greater extent in green-glass factories. From the above table it will be noticed 4 plate-glass works, employing 443 hands, pay monthly, and 2, employing 513 hands, pay weekly. In window-glass, 37 works, employing 2,575 hands, pay weekly ; 2, employing 100 hands, every two weeks ; 12, employing 919 hands, pay monthly ; 3, employing 178 hands, on application; and from the balance, employing 118 hands, no statement has been received. In glassware, 47 works, employing, 7,023 hands, pay weekly; 28, employing 5,419 hands, every two weeks; and 1, employing 130 hands, every month; from the balance, employing 68 hands, no returns have been received. In green glass, 28 works, employing 4,033 hands, pay every week; 4, employing 745 hands, every two weeks ; 12, employing 1,423 hands, every month; 2, employing 296 hands, on application, and from the rest, employing 194 hands, no returns have been received. It will thus be seen that of all the employes in glass works 14,144 are paid weekly, 6,264 every two weeks, 2,915 monthly, 474 on application, and as to 380 no statement has been received. METHODS OF PAYMENT. In the following table will be found a condensed statement showing the number of establishments that had stores connected with them, the number that had no stores, and the number from which no statement has been received : Kinds of glass. STOBBB. NO STORES. NO STATEMENT. Number of works. Number of employes. Number of works. Number of employes. Number of works. Number of employes. 2 12 1 12 376 1, 028 900 2,259 4 36 76 30 580 2,493 11, 565 3,896 10 14 14 369 175 536 Total 27 4,563 146 18,534 38 1,080 The establishments concerning which there is no statement are generally idle works or works that are building, which will account for the small number of employes concerning which no statement has been obtained. It should not, however, be inferred from this table that at the works having stores the men are always obliged to deal at them. Wnile this may be true in some instances to what extent, however, I am not able to say in other cases it is not true, as it is entirely optional with the employs' whether he trades at the store or not. In a number of cases the store is only kept as an accommodation to the men, the works being so situated that this is a necessity. The returns also show that at most of the works having stores a considerable portion of the wages of the men are paid in cash. 1046 MANUFACTURE OF GLASS. While all the above is true, and while the small number of establishments having stores is exceedingly gratifying, this question of " truck" is a burning one between employer and employed. In most states "store-pay" is illegal, and the existence of stores in many cases is a violation or an evasion of the law. PRODUCT. The total value of all the glass produced in the United States during the census year was $21,154,571. The following table shows the value of the several kinds of glass produced and the percentage of each kind to the whole : Kinds of glass. Value of product. Percentage of total value. Plate-glass ...... , $888,305 4.10 5, 047, 313 23.86 Glassware 9,568,520 45.23 5 670 433 26.81 Total 21, 154, 571 100.00 MATEEIALS. The total value of all materials and the value of the materials used in each kind of glass is shown in the following tabulated statement : Kinds of glass. Total valoe of materials. Percentage to whole. All kinds $8,028,121 100.00 438,457 5.46 Window-glass -- 1, 849, 530 23.04 3 292,380 41.01 2,448,254 30.49 In Table VIII of this report are given, so far as they were ascertained, the quantities of the different materials used in all kinds of glass. EELATIVE PRODUCTIVE BAJfK OF THE STATES. The following table shows the relative productive rank of the several states and the percentage that the production of each bears to the total product: States. Percentage of Valueofpro- ; pr ^ ac n dnction. ?ea<,h state to whole. States. Percentage of v *r- 0? 3HL to whole. The United States *21, 154, 571 100. 00 Indiana $790 781 3.74 ; ^ Wf . ^ Tr . . . 8, 720, 584 41. 22 748,500 3.54 587 000 > 77 2, 810, 170 13. 28 Kentuckv 388,405 1 84 "New York " 420 796 1L44 Connecticut 160 000 76 Ohio 1,549 320 7.32 California... 140 000 66 919 827 4.35 Michigan 90 000 0.43 901, 343 4. 26 70 000 33 854,345 4.04 Iowa 3 500 0*' It will be noted that Pennsylvania stands first as a producer of glass in the United States, its percentage in value being more than three times that of any other state. About 65 per cent, of this amount is credited to Allegheny county. The pre-eminence of Pennsylvania as a glass-manufacturing state is due to some extent to its extensive supplies of mineral coal, which affords very cheap fuel to the glass houses. The following tables give the relative productive rank of the several states in the manufacture of the several kinds of glass : PLATE-GLASS. State. Value of pro- duction. Percentage of value of production of each state to whole. The United States $868,305 100 00 49*. 400 57 IT '.f* 1 550 37 15 45 843 5.28 Kentucky . 3,512 40 1047 10 MANUFACTURE OF GLASS. WINDOW-GLASS. State. Value of pro- duction. Percentage of value of production of each state to whole. The United States $5, 847, 313 100 00 2, 222, 513 44.03 729 155 14 45 New York 540 903 10 72 373 343 7 40 358 000 7 09 332 000 6 58 229 397 4 54 104 00 2 06 90 000 1 78 68 000 1 35 GLASSWARE. The United States $9 568 5 9 100 00 4 881 312 51 01 New York 1 157 571 12 10 Ohio 1 076 320 11 25 748 500 7 82 704 500 7 36 400 000 4 18 215 330 2 25 160 000 1 67 136 487 1 43 85 000 89 3 500 04 GREEN GLASS. The United States $5 670 433 100 00 1 681 015 29 64 1 616 759 '8 51 New York . 722 322 12 74 528 000 9 31 392 790 6 93 170 000 3 00 169, 563 2.99 California . .. 140, 000 2.47 Ohio . 115, 000 2.03 70, 000 1.23 64,9* 1.15 PRODUCTION OF PLATE-GLASS. As stated, the total value of the plate-glass produced and sold in the census year was $868,305; the total amount cast was 1,700,227 square feet. Of this amount, 1,042,000 square feet, valued at $794,000, were polished and sold, and 484,543 square feet, valued at $113,555, were either sold as rough plate-glass or were in the process of completion at the works on the 31st of May. The balance, J.73,684 square feet, represents the cast plate that had been destroyed in the process of manufacture. The amount of plate-glass sold unpolished, or as cathedral plate, was 377,227 square feet. This would make the total sold, including rough plate and polished plate, 1,419,227 square feet, valued at $868,305. From the returns received it appears that the value per square foot of the polished plate- glass sold was 76 cents. PRODUCTION OF WINDOW-GLASS. The total production of window-glass in the United States was 1,864,734 boxes of 50 square feet, valued at $5,047,313, or an average of $2 70| per box. No attempt was made to ascertain the number of square feet of each size sold, nor what proportion was single and what proportion double thick, as upon inquiry it was found that such an attempt would be useless. PRODUCTION OF GLASSWARE. An attempt was made to arrive at the total number of pieces of certain kinds of glassware made ; but though returns were received from a large number of works giving the number of tumblers, goblets, lamps, lamp-chimneys, and flint bottles or "prescriptions", they were by no means complete. Some of the figures received, however, were 1048 MANUFACTURE OF GLASS. 11 quite suggestive. In Massachusetts, for example, no flint bottles or "prescriptions" were made, but in this state 46,415 dozen tumblers, 111,712 dozen lamp-chimneys, and 14,087 lamps were made. In New York the returns show 888,639 dozen lamp-chimneys and 75,301 lamps. This return, however, is imperfect. In Ohio the reports show 409,713 dozen tumblers, 743,140 dozen lamp-chimneys, and 19,426 lamps. The returns from Pennsylvania in this regard are very imperfect. So far as returns have been received, the make of tumblers was 2,500,000 dozen, of lamp-chimneys 2,719,649 dozen, and of lamps 128,090 dozen. PRODUCTION OP GREEN GLASS. The same lack of statement of detailed production as obtains in flint glass also exists as regards green glass. The chief productions, however, are green and black bottles, beer-bottles, fruit-jars, demijohns, carboys, and vials. In New Jersey the number of green and black bottles is given as 107,547 gross ; of fruit-jars, 51,749 gross, and of beer-bottles, 32,060 gross. In New York, 49,882 gross of green and black bottles, 28,752 gross of fruit-jars, and 12,049 gross of beer-bottles are reported as made. In Pennsylvania the reports show 55,846 gross of green and black bottles, 67,770 gross of fruit-jars, and 27,198 gross of beer-bottles. LOCALITIES IN WHICH GLASS WAS PEODUCED. The states ranking highest in the production of glass are Pennsylvania, New Jersey, New York, and Ohio, each of them producing glass to the value of more than a million and a half dollars during the census year. The following table will show the rank of those counties producing more than $50,000 in aggregate product: Counties. States. Value of pro- ductiou of comity. H Percentage ' of value of prod action of Counties, county to total value. States. Value of pro- duction of county. Percentage of value of production of county to total value. $5,668,212 1, 621, 959 1,318,081 1, 132, 450 947,805 794,020 714,000 650,381 597,277 587,000 523,343 503,587 447,530 361, 315 322,550 309,102 307,500 285,000 265,330 257,000 232,000 200,000 180,664 20.79 Portage ' Ohio ._ . $168,298 160,000 149, 845 149,735 140,400 140,000 140,000 127,182 125.000 123,075 120,000 116,940 102,511 93.000 90,000 80,000 72.000 72,000 70,000 70,000 60.000 55,000 54,000 0.80 0.78 0.71 0.71 0.88 0.66 0.66 0.60 0.59 - 58 0.57 0.55 048 0.44 (i 43 0.38 0.34 0.34 0.33 0.33 0.28 0.26 0.26 Philadelphia do 7.67 Middlesex Kings New York 6.24 Berkshire \faM^hnaAttji 5. 35 Os wego Vw Vnrlr do 4.48 Clark Indiana Ohio 3 76 Oneida New York Ohio 3. 38 San Francisco California ._. . Vew York Missouri 2.82 Bristol Maryland 2. 77 Jefferson 2.47 Steuben 2 33 Onondaffa Kentucky . New York An La Salle Salem Fayette 1. 71 Rock Island Tllinnia Jefferson Missouri Ohio 1 52 Wayne Michigan Middlesex 1.45 Suffolk . . Illinois 1.35 Montgomery 1.25 Hill3boron"h Pennsylvania Kenton "Wayne Kentucky L 22 Ulster Vew Vm-k ._. _ Ohio 1.10 Tompkins An Wayne New York 1 TABLE I. THE PLATE-GLASS WORKS OF THE UNITED STATES AT THE CENSUS OF 1880. S KUMBEK OF FUIIXACES. NUMBER OF HAXDS EMPLOYED. 1 I PRODUCTS. | \ o - s L- ^= ^3 . "3 States. I 1 i ^ 5" "S ,0 3 S i I -3 9 s i '- ~i If s.- s ei A 1 O 'H. | j ,* s = 55 ^ z ? == -r- l = 3 = 3 ~ 3 * 5 1 S 1 5 -- H i P- " H H S o o I | 1 Square feet. Square feet. Sjt nnn 64*> 000 l';0 000 496 400 Kentucky 1 '25 000 2 * 16 35 32 1 i 1 1 008 2 750 20 684 20 684 3 512 Massachusetts . *s ofMi 2 1 1 20 58 57 j 10 395 24 049 209 543 209 543 45 843 Missouri 1 1,150,000 1 1 16 350 314 36 120,000 112, 925 500, 000 400,000 17, 000 322, 550 ! * This docs not inolnde the value of c:iat plnte in process of manufacture, nor of ronsrh plate broken up and used as cullet, but includes only the value of polished plate ;iutl that prut of the roiijih plate IL:>: \vaa sol.'.. 1040 12 MANUFACTURE OF GLASS. TABLE II. THE WINDOW-GLASS WORKS OF THE UNITED STATES AT THE CENSUS OF 1880. States. 1 s i i '1 O NUMBER OF FUKNACES. NUMBER OF HANDS EMPLOYED. g 1 S.j? il r I** EH a . s<3 CO I 1 s PRODUCTS. i 1 H 4 1 b 88 I 7J S fr | . ig I"" Females above 15 years. _ 1 Males 16 years gg 1 and under. Females 15 years and under. S4B it ,!* ' 15 The United States 58 $4, 953, 155 767 3,890 3,755 1 2 $2, 139, 536 $1, 849, 530 1, 864, 734 $5,047,31? t 1 1 4 2 1 1 9 9 6 20 235,000 175, 000 25,000 305, 000 75,000 65,000 40, 000 723, 355 575, 000 455, 000 2, 279, 800 6 3 1 5 4 1 2 15 11 e 34 6 3 1 5 4 1 2 15 11 6 34 58 30 8 42 32 8 14 116 96 56 307 225 169 222 168 3 145, 703 103, 000 101,474 105, 000 115, 271 91, 759 373,313 229, f>7 222 99 48 699 410 273 1,691 222 98 50 48 622 409 269 1,646 131, 454 44,947 30,000 32, 000 266, 294 195, 576 146, 861 1, 043, 701 147, 277 39,245 35, 113 27,706 289, 803 224, 568 106, 510 772, 834 141, 000 41, 866 30, 000 24,000 296, 685 216, 748 127, 122 780, 283 332 000 104, "02 90, COO 68, 01 729, 15(1 540, 90? 358, OOf 2, 222, 51?, 1 4 "S w Jerse * 77 1 4 Ohio 43 2 * Not in operation during the census year. TABLE III. THE GLASSWARE WORKS OF THE UNITED STATES AT THE CENSUS OF 1880. States. No. of establishments. i 1 o NUMBER OF FURNACES. i NUMBER OF HANDS EMPLOYED. H ** fl H u tJCeS c3 H H i C5 ^ 1 Other kinds. A 1 S o t . 1 r N Females above 15 years. Males 10 years and uuder. Females ISyears and under. The United States 91 $7, 409, 278 162 17 2 143 1,559 12, 640. 8,253 513 3,824 50 $4,452,417 $3, 292, 3W> $9, 568, 520 1 1 1 2 1 2 6 2 3 14 10 44 4 130,000 25, 000 20, 000 32, 000 250, 000 55, 000 603,000 100,000 310, 000 775, 600 579, 750 3, 978, 406 550, 522 1 1 2 2 2 2 15 2 10 24 18 75 8 1 1 2 1 1 2 15 2 10 24 13 65 6 10 6 16 20 22 17 143 21 89 215 191 727 82 160 130 2 28 65,000 70, OCO 160, 00( Illinois * 1 1 35 209 85 789 217 900 1,847 1,225 6,227 946 24 106 60 673 120 525 1,157 781 4,062 615 2 10 9 92 25 60 97 350 653 363 1,919 228 2,000 105, 292 22,000 328, 000 61, 339 250,000 591, 576 452, 659 2, 262, 901 311, 650 3,248 60, 466 26, 000 266, 570 43, 035 100, 000 426, 826 309, 270 1, 778, 901 208, 064 3,500 215, 330 85,000 704, 50fr 136, 487 400, 000 1, 157, 571 1, 076, 320 4, 881, 312 748, 500 1 56 25 30 81 207 100 New York 7 Ohio 5 8 2 2 39 3 "West Virginia * Not in operation during census year. TABLE IV. THE GREEN-GLASS WORKS OF THE UNITED STATES AT THE CENSUS OF 1880. States. | 1 s 1 I NUMBER OF FURNACES. NUMBER OF HANDS EMPLOYED. Total amount paid in wages during the year. 1 1 o . F 1 H i -3 1 1 1 H 1 1 Other kinds. I I jl Females above 15 years. Males 16 years and under. Females 15 years and under. The United States 56 $4, 895, 266 88 2 3 83 540 6,691. 4,948 136 1,574 33 $2, 259, 894 $2, 448, 254 $5, 670, 433 California .... 1 2 1 3 2 1 1 2 15 9 4 14 75,000 190,000 125,000 295,000 76,000 100,000 25,000 140, 000 50, 000 1, 694, 666 583, 000 1GO, ICO 1, 381, 500 1 4 2 3 3 1 1 4 2 31 13 5 18 1 4 2 3 3 1 1 2 30 11 5 16 7 36 14 17 17 11 8 24 8 172 62 30 134 113 507 180 278 305 80 418 107 226 242 33 97 73 52 63 45,924 196, 324 20, 357 44, 022 80,800 48, 070 196,368 30, 000 70, SfS 66,405 140, 000 528, 000 64,984 169, 563 170, 000 Illinois 350 102 1,979 821 190 1,866 227 80 1,615 550 120 1,291 8 21 20 87 123 14 341 245 70 463 2 6 25 167, 759 25,600 783, 744 259, 660 45, 000 590, 704 168, 205 34, 000 698, 543 293, 297 43, 553 798, 925 392, 790 70, 000 1, 681, 015 722, 322 115, 000 1, 616, 709 1 1 1 New York Ohio 1 1 * Not in operation durinc the ceasus year. t Building. MANUFACTURE OF GLASS. 13 TABLE V. GLASS WORKS IDLE AND BUILDING IN THE UNITED STATES AT THE CENSUS OF 1880. 1. FURNACES THAT MADE NO GLASS IN THE CENSUS TEAR. No. of Classes. establish- ments. Capital FUBXACKS. Kind and number. Total number of pots. Gas. T.^v Other Tank - kinds. Total number. Plate-glass - 1 1 10 19 7 1 10 22 8 8 82 201 58 $90,000 287.000 234,000 3 1 Total ... 34 591,000 4 37 41 349 2. ALL FURNACES BUILDING AND NOT COMPLETED IN THE CENSUS YEAR. Classes. No. of establish- ments. Capital. FVRXACE8. Kind and number. Total nnmber of pots. Gas. T,,v Other Total Tant kinds, nnmber. Plate-glass 1 4 12 5 1 1 4 12 5 M 36 129 31 $80,000 235,000 54,100 4 8 5 4 Total . .. 22 389,100 5 17 22 212 PLATE-GLASS. 3. FURNACES THAT MADE NO GLASS IN THE CENSUS TEAR. FVRXACK8. No. of States. establish- ments. Capital. Kind and number. Total Gas. T...V Other Tank - kinds. Total number. of pots. Kentucky 1 i 1 g Total 1 1 i g 4. FURNACES BUILDING AND NOT COMPLETED IN THE CENSUS TEAR. FUSXACI8. No. of States. establish- ments. Capital. . Kind and number. Total ft*. TJanV Other Total .as. Tank. tjnd8 numbel . of pots. Missouri 1 1 1 16 Total 1 1 i 10 i WINDOW-GLASS. 5. FURNACES THAT MADE NO GLASS IN THE CENSUS TEAR. States. N. of establish- ments. Capital. FrBXACES. Kind and number. Total number of pots. Gas. Tank. Other Total kinds, nnmber. Tllinnii? _ _ 1 1 2 1 2 1 2 1 1 2 1 2 2 1 1 2 1 2 1 2 10 8 16 8 14 18 Iowa . $25,000 Massachusetts .. Missouri 10,000 10,000 45,000 New York Total . . . 10 90.000 10 10 g> 1051 14 MANUFACTURE OF GLASS. WINDOW-GLASS Continued. 6. FURNACES BUILDING AND NOT COMPLETED IN THE CENSUS TEAR. States. No. of establish- ments. Capital. FURNACES. Kind and number. Total number of pots. Gas. Tank. Other kinds. Total number. Illinois , 1 1 1 1 $35,000 1 1 1 1 1 1 1 1 10 6 10 10 New Jersey New York Ohio 45,000 Total 4 80,000 4 4 36 GLASSWARE. 7. FURNACES THAT MADE NO GLASS IN THE CENSUS TEAR. States. No. of establish, mentg. Capital. FURNACES. Kind and number. Total number of pots. Gas. Tank. Other kinds. Total number. District of Columbia 1 1 3 2 2 2 4 $25,000 20,000 6,000 110,000 30,000 1 2 7 3 2 1 2 7 3 2 2 5 6 16 70 26 11 24 48 Illinois New York Ohio... 2 1 76,000 4 Total 15 267,000 3 19 22 201 8. FURNACES BUILDING AND NOT COMPLETED IN THE CENSUS YEAR. States. No. of establish- ments. Capital. FURNACES. Kind and number. Total number of pots. Gas. Tank. O'ther kinds. Total number. 1 1 1 1 3 5 $20,600 30,000 1 1 1 1 1 3 5 13 8 10 8 38 52 1 1 1 1 4 New Jersey Ohio 95,000 90,000 2 1 Total 12 235,000 4 8 12 129 GREEN GLASS. 9.-FURNACTES THAT MADE NO GLASS IN THE CENSUS YEAR. State*. No. of establish- ments. Capital. FURNACES. Kind and number. Total number of pts. Gas. Tank. Other kinds. Total number. Massachusetts 1 2 4 1 si oo. 000 44,000 80,000 10, 000 1 2 4 1 2 4 1 11 12 29 6 Ohio 1 Total 8 234,000 , 1 7 8 58 10. FURNACES BUILDING AND NOT COMPLETED IN THE CENSUS YEAR. States. No. of establish- ments. Capital. FURNACES. Kind and number. Total number of pots. Gas. Tank. Other kinds. Total number. Ohio 1 1 1 2 21,100 10,000 23, 000 1 1 1 2 1 1 1 2 6 5 5 15 New York Total . ..., 5 54,100 5 5 31 MANUFACTURE OF GLASS. 15 TABLE VI. CONSOLIDATED STATISTICS OF ALL THE GLASS WORKS OF THE UNITED STATES AT THE CENSUS OF 1880, BY STATES. i XUMB1 [BOFf UBXAC ESAXI POTS. XUJO 3ER OF 1ASDS KJIPLOr ID. a a | i State* ! 3 3 I u H 1 i Other kinds. 1 1 CO O li r. >> Females above 15 years. Males 16 years and under. Females 15 years and under. 1 j| l|i OR H "3 I 1 H s _ The United States 211 $19, 844, 699 348 21 5 322 2,982 24 177 17,778 741 5,566 12 $9, 144, 100 $8,028,621 $21 154,571 " 75 000 1 1 7 113 80 33 45 924 48,070 140 000 1 130 000 1 1 10 160 130 2 28 65 000 70 000 160 000 District of Colombia* 1 25,000 1 1 6 Illinois 7 445 000 12 12 110 732 632 100 342,027 297 842 901 343 4 1,442,000 10 10 108 862 695 53 108 6 284 207 433 733 790 781 3 57 000 3 1 2 28 35 9 4 2 9 2.000 3 248 3 500 5 795 000 6 55 522 364 11 145 2 150 322 134 104 388, 405 g 436 000 10 10 76 612 524 88 234 254 239 682 587 000 11 823 000 22 1 21 206 946 828 58 60 383 342 329 864 854 345 Michigan 1 65 000 1 8 54 50 4 30 000 35 113 90 000 1 25 000 1 8 Missouri g 1 430 000 9 1 g 965 709 36 220 381,098 351,871 919 827 50 000 2 2 8 102 80 g 14 25 600 34,000 70 000 27 2,728 021 56 I 55 377 3 578 2 762 46 768 2 1 300 038 1 088 346 2,810 170 X ew York 32 1 933 600 48 1 I 46 373 3,078 2,116 50 899 13 1 046 812 944 691 2 420 796 Ohio 20 1 194 850 29 5 24 277 1 688 1 170 81 437 644,520 459 333 1 549 320 78 7 639 706 127 g 3 115 1 168 9 784 6 999 294 2,425 68 3 897 306 3 350 660 8,720 584 4 550 522 g 2 6 82 946 615 100 228 3 311 650 208,064 748,500 Not in operation during census year. t Building. TABLE VII. CONSOLIDATED STATISTICS OF ALL THE GLASS WOEKS OF THE UNITED STATES AT THE CENSUS OF 1880, BY STATES AND COUNTIES. CALIFORNIA. I KUMBRB OF FURNACES AXD POTS. XUUBEB OF HANDS EMPLOYED. Jj 1 i a s* 1 nd : = 1 |f "3 . Connties. S = 3 11 $ - i | 1 t A 1 1 | 1 ^~ i" = r . 3|| f >> "s t- 1 M O H H O & P a s. o H H H l $75,000 1 1 7 113 80 33 $45,924 $48,070 $140,000 CONNECTICUT. Middlesex 1 i *130 000 1 1 10 1 160 130 2 28 $65,000 $70,000 $160,000 DISTRICT OF COLUMBIA. l y>s ooo ! i 1 g * Xot in operation during census year. ILLINOIS. Total for State 7 $445,000 12 12 110 732 sy> 100 *349 no? $^*97 84 9 $901 343 Cook* : 1 20 000 9 J i LaSalle 4 235 000 6 $ 387 337 50 195 508 168,755 523 343 140 000 2 2 14 280 "30 50 101 519 9 707 85 000 Rock Island I 1 50 000 > > 9A 65 165 45 (XX) 36 380 93 000 * Not in operation daring census year. 1053 16 MANUFACTURE OF GLASS. TABLE VIL STATISTICS OF GLASS WOKKS, BY STATES AND COUNTIES, ETC.: 1880. INDIANA. Counties. Number of establish- ments. 3 '1 HUMBEB OF FUBNACES AND POTS. NUHBEB OF BANDS EMPLOYED. j!l | CM O f 1 I i M O fi H 3 H I A a H Other kinds. (S EH IP f-t 1| 3 Females above 15 years. Children and youths. Total for State 4 $1, 442, 000 10 10 108 862 695 53 114 $284,207 $433, 733 $790, 7(1 Clark 1 3 142, 000 1, 300, 000 2 8 2 8 42 163 699 131 564 13 40 19 95 56,850 227,357 70, 133 363,600 140,400 650,381 Floyd Clark 1 3 142, 000 1, 300, 000 2 8 2 8 1<5 2 163 699 131 564 13 40 19 95 56,850 227,357 70, 133 363,600 140,400 650,381 Floyd IOWA. Total for State 3 $57,000 3 1 2 28 35 24 2 $2,000 $3,248 $3,500 1 1 1 20,000 12,000 25,000 1 1 1 1 13 7 8 1 1 35 24 2 9 2,000 3,248 S.500 Scottl * Building. tldle. KENTUCKY. Total for State 5 $795, 000 7 1 6 55 522 364 11 147 $150, 322 $134,104 $388,405 3 2 295,000 500, 000 4 3 4 2 28 27 169 353 132 232 1 10 36 111 32, 917 117, 405 37, 079 97, 025 123,075 265,330 1 MARYLAND. Total for State . ... .. .. 8 $436,000 10 10 76 612 524 88 $234,254 $239,682 $587,000 Allegan v * .. . - 1 7 30,000 406,000 1 9 1 9 8 68 612 524 88 234,254 239,682 587,000 * Building. MASSACHUSETTS. Total for State 11 $823,000 22 1 21 206 946 828 58 60 $383,342 $329,864 $854,345 2 4 1 3 1 206,000 120,000 110,000 300, 000 87,000 5 6 2 7 2 5 5 2 7 2 50 52 20 70 14 217 19T 130 352 90 180 155 124 306 63 25 2 4 24 3 12 100, 000 55, 342 50,000 151, 000 27,000 85,000 63,294 32,000 125, 500 24, 070 200,000 149, 845 125,000 307,500 72,000 Berkshire . 1 Bristol . 2 22 24 Middlesex Suffolk MICHIGAN. Wayne 1 $65,000 1 1 8 . 54 50 4 $30,000 $35, 113 $90,000 MISSISSIPPI. Jackson * 1 $25, 000 1 1 8 * Building. MISSOURI. Total for State . . 6 $1, 430, 000 9 1 8 75 965 709 36 220 $381, 098 $351, 871 $919, 827 Jefferson 1 5 1, 150, 000 280,000 1 8 1 16 59 350 615 314 395 36 120, 000 261, 098 112, 925 238,946 322,550 597, 277 Saint Louis 8 220 NEW HAMPSHIRE. HillBborongh 1 $50,000 2 ! 2 8 102 80 8 14 $25,600! $34,000 $70,000 1054 MANUFACTURE OF GLASS. 17 TABLE VlL STATISTICS OF GLASS WORKS, BY STATES AND COUNTIES, ETC.: 1880. NEW JERSEY. Counties. Number of establish- meutl. ! o KVMBKB OF FUR5ACKS AXD POTS. XUHBEB OF HANDS EXPLOITED. = z ^ !l IS fk yi 1 1 % 2 I M O mi 1 , 1 x Ulkur kln.lH. 3 1 H o II J " 3 I'YinnloH abovn 15 ycai*. Children and youths. 'Total for State 27 $2,728,021 56 1 55 377 3,578 2,762 46 770 $1, 300, 038 $1,088,346 $2,810,1?$ -Atlantic* 1 1 1 4 5 24 13 1 7 8 34 34 172 84 8 37 3 4 10 5 1 3 130,000 290,000 805,021 1,175,000 30,000 298,000 4 5 24 14 1 7 | 244 1,783 1,051 us 1.232 854 46 506 196 106,622 586,632 426,900 104,880 407,335 373,900 2S2.38& 1,132,450 947,865 45 1 Gloucester 1 Hudson * .Salem . - 500 478 22 179,884 202,231 447,53* * Idle. NEW YORK. Total for State .. .. 32 $1 933,600 48 1 1 46 373 3 078 2.116 50 912 $1,048,812 $944,691 $2,420 796 1 23 000 1 1 5 Columbia 1 10 900 1 1 1 12 g g 6.000 6.377 13 140 1 50 000 1 1 104 68 36 11.625 13 755 27 145 Erie 1 30 000 1 1 5 60 42 18 22 166 16, 974 42, 909 Jefferson t 1 10 000 1 8 Kin^g . . *. I 9 930 600 22 1 21 m 1 854 1 158 36 660 630 857 489 593 1 318 081 1 "' 1 1 1 g 1 45 000 1 1 7 120 76 3 41 18,000 23 055 55 000 2 100 000 2 2 20 83 83 63,179 68 518 140 000 1 130 000 2 2 16 73 72 1 41,388 40 589 116,940 2 70 000 4 29 220 119 101 51 96"' 49 773 Vi 182 Oswego 3 160 000 4 32 152 152 47 394 63 156 149 735 Steuben 1 75 000 ; 2 18 108 107 1 51 000 "' il * 48,000 120 000 1 40 000 i 1 10 60 60 20 000 23.257 60 000 Ulster 1 25 000 2 > 13 100 60 10 30 25 000 41 010 70 000 2 150 000 2 2 18 132 113 19* 58,241 60 634 180 664 Building. t Idle. OHIO. Total for State 20 $1 194 850 29 5 24 277 1 688 1 170 81 437 $644 520 $459 333 $1 549,32* 485,350 15 3 1 151 829 528 51 250 335 805 225 872 794 920 Franklin .. . 50 000 1 1 10 50 50 16, 000 13 200 45 000 210 000 5 2 3 56 386 253 30 103 122.202 90 843 309 102 22,000 1 1 >72 000 4 28 250 180 70 90 000 72,318 23 00* Portage 155,500 3 . 3 26 173 159 14 80 513 57 100 ^ Ml -i* i, a * Idle. PENNSYLVANIA. Total for State 78 $7 639,706 127 9 3 115 1 168 9,784 6,999 294 2,491 $3,897,306 $3 350 660 $8,720 584 51 5 4S1 000 85 5 1 77 797 6,053 4 442 141 1,470 2 686,425 2, 139 658 5 668 212 1 30 000 1 1 10 4 256 437 7 2 5 79 544 375 11 158 193 000 211 000 503 587 Fayette 3 171 800 5 44 313 310 3 137 959 84,043 361 315 2 6 000 2 2 18 125 122 3 46 900 42,638 102, 511 1 100 000 2 o 13 * 75 70 ! 26,000 40 000 7 00* 1 30 000 1 1 5 80 65 15 25 000 36 120 80 000 Philadelphia 11 i 212. 419 18 2 16 158 2 237 1 358 128 751 655 022 696 393 1,621,959 Tioga 2 66,000 16 45 43 2 23 000 29 515 54 000 "Wayne 4 - 4 4 M 312 214 14 84 104 000 71 293 257 009 * Building. WEST VIRGINIA. Total for State 4 $550 522 8 2 6 82 946 615 100 231 $311 659 $208 064 $748,50* Brooke 1 50 000 1 1 10 128 90 ; 13 25 15 200 15,500 , 34,500 Ohio 3 500 5"' 7 2 5 7 818 525 ' "06 "96,450 192, 56 1 714,000 i i ll 18 MANUFACTURE OF GLASS. TABLE VIII.. CONSOLIDATED STATISTICS OF THE MATERIALS USED IN THE MANUFACTURE OF GLASS, AS REPORTED AT THE CENSUS OF 1880. States. Mixing sand. Grinding sand. Soda-ash. Ni Boda! fsalt - cake - Salt. Lime. Lime- stone. Litharge. Pearl-ash. Arsenic. Manga- nese. Tons. 155, 447 Tone. 39,500 Tom. 49, 626 Tons. 2,859 Tom. 7,877 Tom. 1,909 Bushels. 869, 886 Tom. 2,597 Pounds. 2,313,203 Pounds. 592, 932 Pounds. 713, 974 Pounds. 191, 14 1 200 520 55 6,875 9,767 7,124 25 3,543 5,344 2,205 650 8,042 500 26,282 16,122 10,008 2,495 2,854 10 840 1,902 392 225 3,071 200 8,274 5,865 3,244 18, 419 1,315 648 611 83 49,607 47,842 650 10,300 62, 865 2,348 3,500 47, 275 2,800 174, 680 98,854 45,635 309, 122 7,533 300 26, 100 32,000 32, 300 2 49 36 75 400 1,600 1,500 9,049 337 36 255 25 40 12 7,000 20, 000 302 2,710 6, 697 930 24, 000 -y 346 298, 260 130, 111 2 233 g 7,200 31 360 3, 960 200 1,320 26 233 4,822 p 120 194 332 1,841 179 163 204 101 392 455 20,000 559, 257 210,000 1, 218, 688 100 142, 456 28, 000 268,496 3,769 38, 453 6,600 28, 916 547,266 12,000 27,505 16, 436 110, 178 8,518 New York * Ohio 61 452 1,124 / 3,183 States. Fire clay, American. Fire clay, English. Fire clay, German. Pots. Coal. Coke. Wood. Lumber. Casks and barrels. Nails. Straw and hay. Grand total Pounds. 9,196,655 Pound*. 110, 000 Pounds. 7,927,236 Number. 13,655 Tom. 646,898 Tons. 28, 410 Cords. 63,867 M./eet. 53,585 Number. 914, 619 Kegs. 15, 150 Tons. 21, 298 120,000 24,000 56,000 60 16 627 1,100 1 202 587 150 12Q. 601 75 2,118 1,661 835 5,170 332 1,650 1,800 35, 242 61, 050 400 12, 829 15,723 10,899 3,600 36, 070 1,000 61, 530 d2, 266 54,945 278, 575 19, 319 375 50 4,212 460 128 100 50 72 300 400 71 40 982 817,000 662,000 37,500 165, 000 68,000 253, 679 75,000 951, 350 16,000 30, 000 2,012 1,767 18 1,115 2,210 301 300 1,154 80 10,529 5,201 3,098 24, 834 838 4,500 544 1,040 10 690 593 148 60 512 25 3,596 1,698 670 5,062 452 941 467 1 1,155 409 325 40 617 25 3,002 2, 328 1,375 9,787 754 800 400 1,200 53, 475 1,000 624, 000 152, 800 100, 000 60 1,848 1,184 600 3,203 1,000 29, 144 11,247 1,488 8,996 60,000 1,017 781 200 1,500 25, 000 2, 251, 998 1, 595, 650 147, 600 2, 927, 188 629, 000 242, 000 700, 425 3, 541, 981 933,720 31,000 147, 977 86, 835 516, 520 70, 312 2,484 3,935 16,277 1,923 Ohio 26,000 West Virginia ... i 1056 MANUFACTURE OF GLASS. 19 CHAPTER II. GLASS: ITS COMPOSITION, CLASSIFICATION, AND PKOPERTIES. DIFFICULTY OF DEFINITION. It is extremely difficult, if not impossible, to give a definition of glass that shall be simple and yet embrace all substances to which the term is properly applied. GLASS, CHEMICAL AND COMMERCIAL. Iii chemistry many compounds of silica, borax, tin, antimony, and other substances are called glass, being known as " silicate glass", " phosphate glass", or " borax glass", according to the material of the compound. Indeed, any product of fusion that is hard and brittle and has the peculiar luster called vitreous is chemically known as glass. Commercially, however, the word glass is, with few exceptions, chiefly the enamels applied only to the silicates, or the compounds of silica, generally in the form of sand, with lime, soda, potash, the oxide of lead, and similar bases. The manufactured glass of commerce, however, is not a simple silicate, but, with one exception (water glass), is a fused mixture of two or more simple silicates. Flint glass, for example, is a double silicate of potash and lead ; window-glass a tersilicate of potash, soda, and lime. In the process of manufacture, however, these simple silicates are not first separately produced and then fused, but the making of the "metal", as the fused glass is termed, is a double process, though a continuous one, the simple silicates of lime, or soda, or lead, or potash, as the case may be, being first formed in the pot of the glass-maker from the materials charged, and then, without any break in the continuity of the process, these simple silicates are fused in the same pot, and at the same melting, into the vitrified, non-crystalline material we know as glass, (a) CHIEF CONSTITUENTS. It will thus be seen that the principal and essential constituents of glass are silica or sand and an alkali, or sometimes a metallic oxide. The chief alkalies used are soda, lime, and potash, and the chief oxide is that of lead. Other oxides, as those of zinc, tin, and antimony, are sometimes used; and other materials, as manganese, oxide of iron, arsenic, etc., are found in glass, but they are there as impurities, or as materials used to correct impurities. VARIABILITY OF COMPOSITION. While these are the chief constituents, and while it is possible to indicate approximately the composition of the different kinds of glass, this composition, even in different specimens of the same kind, is by no means definite. The relative quantities of silica and the alkalies vary greatly. Flint or lead glass, for example, is made harder or softer as the proportion of sand is increased or decreased, though in these varying degrees of hardness it would be termed a silicate of potash and lead. The crystal, flint glass, and Strass of Ure's classification differ greatly in their properties, appearance, and composition, but each is regarded as a silicate of potash and lead. In a word, while glass is regarded as a chemical compound a silicate unlike most chemical compounds, it has no fixed definite composition in the several varieties. Indeed, though constant attempts have been made to produce as a commercial article a glass of that fixed, definite composition that experience has shown to be the best for a given kind, but little success has been attained, except, perhaps, at times at the celebrated plate-glass works of Saiut-Gobain, France. The conditions of manufacture, especially in melting and the varying quality of the ingredients, preclude this, (b) APPROXIMATE COMPOSITION. Keeping in mind this variability in the composition of glass, the proportion of the essential ingredients in the chief varieties included in the report of the special agent may be given approximately as follows : Kinds of glass. Silica. Soda. Lime. Potash. Gride of lead. Oiide of iron. Alumina. Cast plate . . Per ,.(. 74 Per cent. 12 Percent. 5 5 Percent. 5 50 Percent. Percent. Percent. Window 73 13.0 13 Lead flint 52 13 67 33.28 73 3 14 5 12 7 60 *>0 3 00 4 10 1W DIFFICULTY OF CLASSIFICATION CHEMICALLY. It has been as difficult to make a classification of glass as to define it. This difficulty chiefly arises from the variability of composition, already noted, as well as from different writers considering glass from different standpoints, some regarding it chemically, others commercially. The a Ure defines glass as "a transparent solid formed by the fusion of siliceous and alkaline matter". (See Ure'g Dictionary, article, Glass.) Fownes, iu his Chemistry, says: "Glass is a mixture of various insoluble silicates with excess of silica, altogether destitute of crystalline structure." Lardner, in his Cabinet Cyclopcedia, includes " all mineral substances which, on the application of heat, pass through a state of fusion into hard and brittle masses, and which, if then broken, exhibit a lustrous fracture ". The definition of Dr. Benrath, of Germany, recently published, is perhaps the best. He says: " By glass, in the technical sense of the term, we understand a silicate or silicate mixture which at a high temperature is thin fluid, and which, as the temperature falls, passes gradually through the tenaciously fluid into the solid condition ; in which, furthermore, the unassisted eye can perceive no crystalline structure, and which is impenetrable to both liquid and gaseous fluids." b A discussion of the reasons for this lack of uniformity of composition belongs properly to chemistry. 7 M M 20 MANUFACTURE OF GLASS. classification used iu Lite English works, that of Ure, (a) is not at all satisfactory, as while it professes to he. a chemical classification, it is neither that nor a commercial classification. It seems well-nigh impossible to make a chemical classification that shall be satisfactory. (b) DIFFICULTY OF CLASSIFICATION COMMERCIALLY. A similar difficulty, though from other causes, presents itself in any attempt to classify glass on any basis, especially on a commercial basis. The names that have attached themselves to the different kinds of glass are almost innumerable. Without attempting a classification, then, that shall be complete, it will be sufficient for the purposes of this report, as it chiefly considers glass as an article of commerce, to mention some of the most prominent of these commercial varieties. (c\ CLASSIFICATION. In gathering the statistics of glass at the present census a classification into four general varieties was used. This classification, somewhat extended, to include sub-varieties not made in this country, is as follows : 1. PLATE-GLASS is glass which is cast upon a flat, smooth, cast-iron table and immediately rolled into sheet* or plates of a required thickness by heavy rollers. Without being allowed to cool, the plates are laid in annealing ovens. It is chemically a silicate of lime and soda or potash. Roughplate is the crude plate-glass as it comes from the annealing oven. Rolled plate, or rolled cathedral plate, is rough plate from one-eighth to one-quarter of an inch in thickness. Ribbed plate is a rough plate, with regular corrugations or ribs. Polished plate, to which the term plate-glass is usually applied, is the rough plate that has been submitted to the successive operations of grinding, smoothing, and polishing to prepare it for use for windows, mirrors, etc. These are the only varieties of plate-glass produced in this country, and are all the varieties that are produced from cast glass. Formerly a blown glass, made somewhat heavier than sheet or window glass, and called blown plate, was made in England, and is still made in Germany to some extent. Patent plate is also a name applied in England to ordinary sheet glass ground and polished by Chance's patent process. 2. WINDOW-GLASS. This is more properly termed sheet or cylinder glass. It is the ordinary window-glass of commerce, and is blown in cylinders, which are opened and flattened out into sheets, some as large as 60 by 40 or 80 by 30 inches. It is a silicate of lime and soda or potash. Colored or painted glass, so far as the same is used for windows, may be included in this class. This is a silicate of lime and soda with the necessary coloring matter. It receives different names, according to the method of applying the color. It is termed pot metal (d) when the color permeates the whole body of the glass, fashed or double glass (ft) when the colors are confined to the surface, and stained glass when the colors are burned into the surface in the glass-stainer's kiln. Croicn-glass is also a variety of blown window-glass that is no longer made in this country, though it is still made in England. It is first blown, and then by peculiar and very skillful manipulations formed into a circular table with a bullion or bull's-eye in the center. From this table moderate-sized window-plates are cut which show a crowned surface. 3. FLINT GLASS. This term has a wide application, and includes table and other glassware, both blown and pressed, chimneys, and a large class of bottles and vials, articles often differing widely in chemical composition. a This classificalion is as follows (see Dictionary of Arts, etc., article, "Glass" ). 1. Soluble glass: a simple silicate of potash or soda, or both of these alkalies. 2. Crown-glass : a silicate of potash and lime. 3. Bottle-glass: silicate of lime, soda, alumina, and iron. 4. Common window-glass : silicate of soda and lime, sometimes also of potash. 5. Plate-glass: silica, soda or potash, lime, and alumina. 6. Ordinary crystal glass : silicate of potash and lead. 7. Fliut-glass : silicate of potash and lead. 8. Strass : silicate of potash and lead, still richer in lead. 9. Enamel: silicate and stanuate, or antimoniate of potash, or soda and lead. We must remember with regard to this table that crown-glass always contains soda, that alumina and iron are accidental, not essential, constituents of bottle-glass, aud that enamels vary greatly in their composition. Tin is not present in transparent enamels. b Tomlinson's classification, quoted in Lippincolt's Encyclopaedia of Chemistry, vol. ii, page 8, is one of the best. c It may be well to note that glass is divided into two general classes, natural and artificial glass, and these are again subdivided. Natural glass is that produced entirely by natural agencies, without any assistance from man. It includes the mineral obsidian, au impure, semi-transparent glass, varying in color fro 11 gray to black, found in the vicinity of volcanoes, and which was used in the manufacture of works of arts by the ancient Romans and Egyptians, and in later times by the Mexicans ; and the fine capillary glass called Pelc's hair, found at the volcano of Kilanea, in the Sandwich Islands, and water glass, found iu certain springs. Water glass is also found absorbed in certain basaltic rocks, and attempts have been mad", with considerable success, to use decomposed basalt for manufacturing bottle-glass. Artificial glass is that produced in the arts. It includes, in addition to that made in the glasshouses, various slags resulting from metallurgical operations, as blast-furnace slag, which is a lime glass with an excess of lime, and slag-wool, which is an artificial Pelt's Lair. It also includes many chemical glasses. A classification of glass according to method of manufacture is also sometimes made as "cast glass", "blowu glass," and "pressed glass". A classification according to use also sometimes obtains as window-glass, bottle- glass, chemical glass, and one, according to place of manufacture, as Venetian, Egyptian, etc. d Pot metal and flashed glass are al-so made in flint glass. 1038 MANUFACTURE OF GLASS. 21 It includes lime glass or the common flint, sometimes also called German flint, and, by many American manufacturers, crystal glass. It is a silicate of lime and soda or potash. The celebrated Bohemian glass is a lime glass, as is also the " Gobeleterie" of the French, which is a silicate of lime and soda, potash being used only in a better glass. A second general subdivision of flint glass is : Lead glass. This is a silicate of potash and lead which has literally the ring of metal, and is distinguished from the lime glass by this ring and its greater specific gravity. It is also, as a rule, more brilliant. This glass is tho, crystal (cristaux) of the French and the true flint of the English. Strass is a glass very rich in lead, used in the manufacture of artificial gems. Optical glass is both a lead and lime glass, the former known in instrument-making as flint, and the latter as crown, but differing from the "crown" mentioned under "window-glass". These glasses are of different densities and refractive powers, and are used in the manufacture of achromatic object-glasses. The terms "flint" and " crown " glass are, according to Bontemps, applied on the continent of Europe exclusively to optical glass. 4. GREEN GLASS. This is a coarse, greenish glass, often termed bottle-glass, it being used chiefly for common bottles. It is called in this country hollow ware, though the German lohlylcs, or hollow glass, comprises all glass worked into the form of vessels or tubes. The American green glass is a silicate of lime, soda, alumina, and iron, the last two ingredients being found as impurities in the sand, the iron giving the glass its greenish hue. To these varieties might be added many others, which it would exceed the scope of this report to mention. There are some varieties, however, that deserve notice. Among these are water glass, or soluble glass, a silicate of soda or potash, or both, which is highly alkaline, and is used in the manufacture of soap, as a vehicle in painting, a mordant in fixing colors, in the preparation of artificial hydraulic cement, and in the silification of calcareous stone. Enamel is A silicate, borate, stanuate, or antimoniate of potash or soda and lead. Hardened, toughened, or tempered glass is not annealed, as is usual with glass, but is tempered in a hot, oily mixture, as in M. de la Bastie's process, or in peculiarly constructed molds, as in Siemens' process. Spun glass is a glass drawn into threads finer than silk and woven into small articles. Ground glass. The obscuring of the surface of sheet glass or flint-glass is accomplished by the friction of a stone wheel, or a movable rack with pebbles or little stones, water, and sand, or by the sand-blast, or by the fumes of hydrofluoric acid. In figured and cut glass the ground surface is removed in set forms and designs by the use of wheels of stone, wood, or cork, or by the use of hydrofluoric acid, producing both Etclied and embossed gla#s. Iridescent glass is a reproduction by art of the beautiful iridescent colors of ancient glass that has been long buried. To these varieties may be added the beautiful products of ancient and modem Venetian glass mentioned in the chapter on modern glass! SPECIFIC GRAVITY. The specific gravity of glass is a property of considerable importance in connection with the manufacture of object-glasses for achromatic telescopes and of artificial gems, though in the production of common glass but little attention is given to it. In general the power of refracting light increases with the increase of its specific gravity, though density and power of refraction are not strictly parallel. The specific gravity of glass, as well as its brilliancy, varies with its composition, the heavier glasses being the most brilliant, as well as the softest. Lime glass is the lightest, bottle-glass comes next, and lead glass is the densest. Its density is also influenced by the degree of hea f to which it has been exposed during its vitrification, being always least when the temperature has been greatest. "The following are the specific gravities of the glasses named : Lime glass : Bohemian 2.3% Plate-glass : Saint-Gobain }.. 2.488 Cherbourg 2.506 Window-glass 2.732 Bottle-glass 2.732 Lead glass : Common flint 2.9 to 3. 255 Optical ., 3. 3 to 3. 6 CONDUCTIVITY AND TENSION. Glass is a bad conductor of heat and electricity, but all kinds are not equally adapted to become insulators, glasses rich in alkali being bad insulators. The tension and enforced equilibrium in the interior of a mass of glass rapidly cooled, as exhibited, for example, in Prince Rupert's drops, is well known. TENSILE AND CRUSHING STRENGTH. The tensile strength of glass is given at from 2,500 to 9,000 pounds per square inch, according to kind; crushing strength, 6,000 to 10,000 pounds per square inch. A sample of Millville 22 MANUFACTURE OF GLASS. (New Jersey) flooring glass, one inch square and one foot between the end supports, broke under a certain load c7 about 170 pounds. These facts would indicate that glass is considerably stronger than granite, except as regard crushing, in which the two are about equal. DEVITRIFICATION. The devitrification of glass is one of its most important properties, not only because of its bearing on the manufacture and manipulation of glass, but because the devitrified glass, often called Eeaumur's porcelain, can replace porcelain for most of its uses. Devitrification is a crystallization of glass, the ordinary glass being non-crystalline. In the manufacture of glass by the ordinary process it is cooled suddenly, the excessive brittleuess and internal tension thus caused being reduced by annealing. On the other hand, when the fused metal is cooled slowly, the mass assumes a crystalline structure, becomes tough, fibrous, opaque, much less fusible, so hard as to cut other glass, is not so easily filed, and is a better conductor of electricity and heat. DEVITRIFICATION IN ITS RELATION TO MANIPULATION. This property exerts a great influence in the manufacture of glass. It explains, indeed, why, in the making of bottles, so much care is taken to avoid the repeated reheating of the mass which is to be formed into these articles. It would be thoroughly devitrified in a short time; the glass would become hard, difficult to fuse, and would present a multitude of solid grains disseminated in a matter still soft. In the same manner it is evident why green glass, and even common white glass, and still more so bottle-glass, can only be shaped by the lamp of the enameler, when the work is performed with great dispatch. If he work so slowly that he is obliged to reheat several times the glass tube which he is blowing, the mass devitrifies, and all the phenomena show themselves which have just been described. In vain does he then try to blow a bulb, as all the force of his lungs will not avail, and the glass is no longer soft. Beside, the material then becomes striated, semi-opaque, and almost infusible. OTHER PROPERTIES. These and the other properties of glass, together with its wide range of uses in the arts, contribute to render it one of the most curious and interesting of manufactured articles. Composed of materials that are opaque and of but little luster or brilliancy, it is itself exceedingly brilliant and of a most beautiful polish. Perfectly transparent, unless impure, and transmitting light freely, it may readily be obscured or ground so as to soften and diffuse the light. It can be cut in various forms, increasing its richness and brilliancy; it may be engraved in most charming and delicate tracery and figure-work, or it may be tinted with any color, either opaque or transparent, without the least loss of brilliancy or polish. Though not malleable, (a) its ductility is so great that it may be spun in a moment into filaments as small as a spider's web and miles in length, or blown to such gauze-like thinness as to float upon the air. The synonym of brittleness itself, its elasticity as spun glass permits of its being readily bent and woven into cloth, and even tied into knots, while a ball of glass dropped upon an anvil will rebound two-thirds the distance of its fall. Though hard and brittle when cold and incapable of being wrought, when heated it is softened, tenacious, and pliable, and is capable of being molded into any form, while it retains in cooling its beautiful polish. In ordinary use glass resists the action of water and alkalies, and, with a single exception, of all acids, preserving all its beauty, retaining its surface, and not losing the smallest portion of its substance by the most frequent use. (b) EXTENT OF THE USES OF GLASS. For many centuries these properties of glass have caused it to be admired and sought for by all classes. It was the material of many of the most common utensils in the Eoman household in the days of the empire, when porcelain was unknown, as it is of our homes to-day. Not only is it thus devoted to common uses, but art, taking advantage of its properties, has given us the grace and beauty of the Portland, Naples, and Milton vases, the almost unearthly splendor of the emblazoned windows of the mediaeval churches, and the rare color and graceful design of the well-nigh imperishable mosaics. To use the words of Dr. Johnson : Who, when he first saw the sand and ashes by casual inteuseness of heat melted into a metalline form, rugged with excrescences and clouded with impurities, would have imagined that in this shapeless lump lay concealed so many conveniences of life as would in time constitute a great part of the happiness of the world? Yet, by some such fortuitous liquefaction, was mankind taught to procure a body at once in a high degree solid and transparent, which would admit the light of the sun and exclude the violence of the wind, which might extend the sight of the philosopher to new ranges of existence, and charm him at one time with the unbounded extent of the material creatipn and at another with the endless subordination of animal life, and, what is yet of more importance, might supply the decay of nature and succor old age with subsidiary sight. Thus was the first artificer of glass employed, though without his own knowledge or expectation. He was facilitating and prolonging the enjoyments of light, enlarging the avenues of science, and conferring the highest and most lasting pleasures, and was enabling the student to contemplate nature, and the beauty to behold herself, (c) ANALYSES OF GLASS. In the accompanying tables will be found analyses of plate-, window-, flint-, and bottle- a One of the problems regarding glass alleged to have been asked by Aristotle was, "Why is glass not malleablef " The statements . ri(.,it malleable glass may be regarded as fables. ft This is strictly true of glass only under circumstances of ordinary use. All glass is affected by caustic alkalies, especially iii concentrated solutions, as it is thus deprived of silicic acid. The action of mineral acids upon well-compounded glass is less energetic, though not only such acids, hut even pure water, exerts a decomposing influence upon glass, producing its effect, however, very slowly under ordinary circumstances. c Ramller, No. IX. 1060 MANUFACTURE OF GLASS. 23 ANALYSES OF PLATE-GLASS. Kinds of glass. Analysts. Silica. Soda. Potash. Lime. Magnesia. Manganese. Sesnoioxide of iron. Alnmina. French : Peligot 73.00 11.50 15.50 73.05 11 79 15 10 75.90 17.50 3.80 2.80 Do . ..do 73.80 12.10 5.50 5.60 3.50 English : Ch ' Benrath . 70.71 33.25 13 38 1 92 do 72.90 12.45 13 26 1 93 Mayer and Brazier 77.36 13.06 3.01 5.31 0.91 ....do 78.68 11.36 1.34 6.09 Trace. 2.68 Belgian : Bt-m'ath 73.31 13.00 13.34 0. 83 Jaeckel 72.31 11.42 14.96 0.81 73.79 13.94 60 8.61 12 32 68 58 Berthler 68.60 8.10 6.90 1L 00 2.10 10 20 L20 ANALYSES OF WINDOW-GLASS. Kinds of glass. Analysts. Silica. Soda. Lime. Alumina. Sesqnioiido of iron. Dumas .. .. . . 68.00 10.30 14.30 7.60 Do do 69 65 15 22 13 31 1 82 English ....do 69 00 11 10 12.50 7.40 71 40 15.00 12.40 60 Benrath 71 27 20 10 8.14 J. 98 ANALYSES OF FLINT-GLASS. Kinds of glass. Analysts. Silica. Soda. Potash. Lime. Lead. Mag- nesia. Manga- nese. Sesqni- oxide of iron. Alumina. yjlfR GLASS. 72.10 12.40 15.50 Do do 16.30 6.40 Berthier 69.20 3 00 15 80 7 60 2.00 0.50 1.20 73.13 3.07 11 49 10 43 0.26 0.46 0.13 0.30 Berthier 7L70 2.50 12.70 10 30 20 0.30 40 69 40 11 80 9 20 9 60 American O'Hara Glass Company, Pittsburgh . . . De Branner 71.92 14.55 5.14 2.04 Trace. Trace. 8.22 LEAD GLASS. 51.93 13.87 33 28 Berthier 59.20 9 00 28.20 0.40 Do Salvetat 57.50 1 00 9 00 32.50 Berthier 51.40 9.40 37.40 0.80 1.20 48 10 12.50 60 38.00 50 Do Sal vf tat 51.00 1 70 7 60 38.30 1. 30 Do ...do ... 54.20 0.90 9.20 34 60 0. 50 Do Benrath 50 18 11 62 38.11 40 44 30 11.75 43 05 Do 42 50 11 70 50 43.50 1 80 53.98 6.71 7.60 29.78 1. 93 Do do 54.12 5 58 7 98 31 27 1 05 ANALYSES OF BOTTLE-GLASS. Kinds of glass. Analysts. Silica. Soda, Potash. Lime. Magnesia. Manga- nese. Sesqni- oxide of iron. Alumina. Trench : Berthier 60.00 60.40 59.60 53.55 45.60 58.40 62.21 63.34 69.82 62.78 64.41 65.77 68.38 22.30 20.70 18.00 29.22 28.10 18.60 22.93 21.34 7.82 6.11 5.81 16.58 10.19 1.20 4.00 ago 4.40 5.74 6.20 8.90 6.10 4.42 8.08 10.40 6.80 6.01 14.00 2.10 1.16 4.72 3. 3. 10 20 3.20 5.48 6.10 1.80 1.91 2.10 1.50 11.24 10.50 . do 0.60 7.00 do 0.40 Dumas Clichy ...do 9.90 5.C9 4.17 18.28 19.14 15.76 Do do . Do do German Do do 2. SO 0.73 3.52 5.90 2.40 Do do Russian ....do 11.75 19.03 Do do 1061 24 MANUFACTURE OF GLASS. CHAPTER III. SAND. DIFFERENT PROPORTIONS OF SILICA IN GLASS. The chief constituent of glass, as well as the only one that enters into the composition of all its varieties, is silica. Though present in all glass, its relative proportion differs greatly, not only in the several varieties, but in different samples of the same variety, and sometimes in different specimens from the same pot or "melting". Indeed, as to its content, not only of silica, but of other ingredients, glass is a most capricious substance. SILICA IN DIFFERENT KINDS OF GLASS. Lead glass contains the least percentage of silica, ranging from 42 to GO per cent., and cast-plate contains the greatest percentage, some analyses showing as high as 79 per cent., the average being about 74 per cent. Window-glass averages about 70 per cent., lime-glass 72 per cent., and green bottle glass 60 per cent. HARDNESS. The hardness of glass depends, as a rule, on the percentage of silica it contains, though it is somewhat affected by the alkali or oxide used as a base. Lead, for example, tends to make glass softer and more fusible and lustrous, while lime renders it refractory and less susceptible to the action of acids and alkalies. The relative hardness of different specimens of either lead or lime glass depends, however, on the amount of silica, that being the harder and less liable to melt which has the most. It would follow, from what has been said, that green glass is the hardest, followed in their order by lime-flint glass, window-glass, plate, and, lastly, lead glass, which ie the softest. FORMS OF SILICA USED. Silica is now used in glass-making almost universally in the form of sand. This also seems to have been the practice at the earlier glass houses, (a) In modern glass houses, however, until some fifty years since, silica for the finer grades o Downer's, Glass- borough, f HiUiard's, Maurice river, t Speer's, Fayette county. J Juniata county. Crystal City. U Lincoln county. ** Silica 99.78 0.22 99.61 0.39 99.69 0.31 98.824 0.935 0.056 0.015 0.0051 98.850 0.980 0.056 0.022 Trace. 99.720 0.080 0.110 0.06 98.84 0.17 Trace. Trace. 98.35 99.90 99.62 99.66 0.33 0.08 / Chlorine Trace. 0.31 0.07 Trace. Trace. 0.165' 0.130 Trace. 0.42 Trace. 0.09 0.22 0.030 0.23 Total 100. 00 100.00 100.00 100.0004 100. 038 100. 000 99.18 100.00 M.M * Authority : S. Dana Hayes. t Authority : Professor Cook. t Authority: Otto Wuth. Authority : A. S. McCreath. || Authority : C. F. Chandler. U Authority : Crystal City Plate-Glass Company. ** Authority: Chanvenet. CHAPTER IV. ALKALIES AND OTHER MATERIALS. CHIEF BASES USED IN GLASS-MAKING. As has already been stated, the essential elements of glass are silica, which acts the part of an acid, and some one or more bases, either alkaline or metallic. The bases most commonly found in glass are soda, potash, lime, and oxide of lead. These bases, however, are not mixed in the " batch ", as the combined materials ready for melting are termed, in the form in which they are found in the glass. Soda, for example, is not used in the glass houses as soda, but as the carbonate (soda-ash) or sulphate of soda (salt-cake), or as chloride of sodium (common salt) or nitrate of soda. In the process of melting these compounds are decomposed, the soda uniting with the silica, forming the glass, the balance of the compound passing off as gas or in the " glass-gall" or " sandiver ", as the scum on the top of the melted glass is called. ANCIENT GLASS A SODA GLASS AND PERISHABLE. Glass is frequently named from the base that enters most largely into its composition, as " soda glass", "potash glass," "lime glass," and " lead glass". Ancient glasa was a soda glass containing from 3 to 8 per cent, of lime, the lime being present as an impurity, and not as an ingredient purposely used iii its manufacture. It is to this impurity, however, as will be seen further on, that we doubtless owe the preservation of many of the specimens of ancient glass that have come down to us. Soda glass, or glass with an excess of soda, is really soluble glass, even dampness in course of time disintegrating it. Blancourt, in the amusing preface to his Art of Glass, states that Venetian glass " will dissolve in the earth or in cold and moist places if there be more salt in it proportionately than sand". Bernard Palissy notes the disintegration of the glass in the windows of the churches of Poitiers and Brittany, and ascribes it to "the damp and rain which have melted part of the salt of the glass". As most of the specimens of the glnss makers' art of the ancient world have come to us buried in tumuli or tombs, it is probable that even the fragments of most of this ancient soda glass have dissolved, and that only has been preserved which contained considerable lime and was buried in localities calculated to preserve it from dampness. SOURCES OF SUPPLY OF SODA FOR ANCIENT GLASS HOUSES. The chief source of supply for soda for the earliest glass houses was Egypt. Phoanicia obtained its supply from that country ; and Pliny, in his description of glass-making at Rome, states that " sand and Egyptian soda in the proportion of one part of sand to three of crude soda were used". Not only did these very early glass houses obtain their soda from Egypt, but until a somewhat recent period the " natron of Egypt " was largely used in glass-making in Venice and the, south of France. This Egyptian soda, which contained carbonate, sulphate, and muriate of soda, is found native on the banks of the natron lakes that abounded in a valley extending northwest from Memphis, and by reason of its abundance <*s the seat of a large glass industry, remains of ancient glass works being found there by the scientists of the Egyptian expedition of Napoleon I. MANUFACTURE OF GLASS. 31 MODERN SOURCES OF SODA. In modern times, and until within the last few years, the chief source of soda for glass has been the ashes of certain plants, chiefly those of the sea and sea-shore. Among the saline products of these ashes so used were the Spanish barilla from the ashes of the salsola plant ; the Scottish and Irish kelp, which as late as sixty years ago furnished the soda for the English crown- and sheet-glass ; the barec or varec of Bretagne and Normandy ; and the Spanish soda of Alicaut and rochette of Syria. These products contained potash and some lime as well as soda, and were simply mixed with sand and melted. They were quite impure, and, as a result, the glass produced, compared with that of to-day, was inferior, being exceedingly variable in character and poor in color. LEBLANC'S DISCOVERY OF SODA- ASH. The unsatisfactory quality of these impure sodas (the best, the Spanish barilla, containing only from 14 to 30 per cent.), as well as the limited quantity produced and uncertain supply, led the French government to offer a prize of 12,000 francs for the discovery of a method of converting common salt into soda. Leblanc not only secured the prize by his discovery of 1792, but opened a new era in glass-making, (a) The plate-glass manufacturers of France were the first of the glass-makers to use the new product, the carbonate of soda or soda-ash, and were soon followed by the makers of window-glass, with a decided improvement in quality and color. USE OF SALT-CAKE. The carbonate of soda prepared by Leblanc's method contains a considerable proportion of undecomposed sulphate, and the glass manufacturers soon found some advantage in the cost of glass by the substitution of this sulphate, or "salt-cake", for the carbonate. As early as 1781 experiments were made with sulphate of soda, and in 1803 Baader began its use in the glass houses of the Bavarian forests; but it was not until 1825 that it was employed in the French glass houses. In England kelp was used until 1831, when it was displaced to a large extent by carbonate of soda. The introduction of sulphate was still more recent, but at present nearly all the window glass of England and the continent is made with salt-cake. The manufacturers of plate-glass still use soda-ash, as they believe that it produces a glass of a somewhat better color. In this country, though many experiments had previously been made, but little sulphate was used until about 1875, soda-ash being the form of soda employed for window-glass. Messrs. Robert C. Schmertz & Co., of Pittsburgh, were the first to use it regularly and continuously, but it is now largely consumed. Sulphate glass is less liable to devitrify or to become " ambitty ", and will bear more lime than carbonate glass, and hence gives a harder glass with a better polish and less liability to "sweating". It is of a bluish color, while the carbonate glass is of a yellowish tint. SOURCE OF SUPPLY OF SODA. The chief source of supply of the soda of the present day is the alkali works of England, which are mainly located in Lancashire and near Newcastle-on-Tyne. It is estimated that the total annual soda production of the world expressed in terms of pure Na^COs is 708,725 tons, of which 432,000 tons are manufactured in Great Britain. Twelve per cent, of British soda and 23 per cent, of the total soda of the world are produced by the ammonia method. The English soda enters into the manufacture of the glass of most of the countries of the world, and is almost the only kind used in this country. THE AMMONIA PROCESS. In 1866 Mr. Ernest Solvay began at Brussels the manufacture of soda by a process that has since been called by his name, the Solvay, or, as it is sometimes termed, the ammonia process. This method bids fair to supersede the Leblanc. The Solvay soda is fully equal in quality to the Leblanc, and can at present be produced more cheaply. This has had a marked effect on the production of the Leblanc soda. Of twenty -five alkali works which were in operation in the neighborhood of Newcastle-on-Tyne. England, a very few years ago, twelve have been closed, and of these no fewer than eight were actually dismantled, in despair of its ever again being possible, except at a loss, to manufacture soda in them by the Leblanc process. The alkali-making districts of Lancashire have advantages over the Newcastle district in the price of salt, in facilities for supplying the American market, and in nearness to some of the centers of soda consumption ; but even there seven or eight of the alkali works are standing idle, and but few of the others are working to their full capacity. In Belgium the production of Leblauc soda has died out, while in France, Germany, and Austria it is only maintained by the aid of import duties and the large demand for the by-product, hydrochloric acid. There are now eighteen ammonia- soda works running in Europe and one in the United States, and seven more are approaching completion, (b) This process is not only of interest to this country because of its cheapening the cost of soda, but also because it holds out the prospect that we may make our own soda for our glass works. The importance of such an industry to us may be gathered from a statement of the imports, which, for the three calendar years 1879, 1880, and 1881, were as follows : 1 879. 1 sso. 1 n. Quantity in pounds. Vain*. Quantity in pounds. Value. Quantity in pounds. Value. Soda-ash 81,072 $1,825,450 96,766 $2, 345, 461 74 158 $1,555 32 Caustic-soda .... 44,980 648.269 43 274 635 894 47 180 656 588 Sai-Boda 66 471 424 414 53 896 155,497 48,797 138,768 a A full account of this discovery and its results may be found in Mr. Henry Chance's lecture "On the Manufacture of Crown and Sheet Glass", Journal of thf Society of Arts, February 15, 1856. b See paper by Mr. Walter Welden before the English Society of Chemical Industry. 32 MANUFACTURE OF GLASS. MANUFACTURE OF SODA-ASH AND SALT-CAKE IN THE UNITED STATES. Though the materials for the manufacture of soda-ash and salt-cake are to be found in great abundance in this country, but little is produced. Mr. Charles Lennig, of the Tacouy chemical works, Philadelphia, produces some 1,500 tons annually of the sulphate, and the Merrimac Chemical Company, of South Wilmington, Massachusetts, and B. Gressili & Sons, of Cleveland, Ohio, were also producers at the close of the census year. The product of these works is used for window-glass, and is equal to any of foreign make, that of the Tacouy works analyzing from 97 to 98 per cent, of sulphate, 1 per cent, of salt undecomposed, one-half to 1 per cent, of excess of sulphuric acid, and.some little insoluble residue. As this sulphate or salt-cake is really a by-product or residuum of the manufacture of muriatic acid, its production in this country is limited by the demand for the acid. Recent developments and the ammonia process, however, promise to change this state of affairs. The salt-wells of Michigan and of New York have been looked upon as the source of a considerable supply, this view being held by British alkali manufacturers who have examined these localities. Eecently a small works using the ammonia process in a modified form has been successfully operated in Michigan, and it is stated that the Solvay Process Company is erecting extensive works at Syracuse, New York. USE OF COMMON SALT. Both the carbonate and the sulphate of soda are prepared from common salt. This has led to many attempts to effect the direct union of silica and salt without the intervening process, but thus far with but little success. At present the only glass made from common salt is the black bottle-glass of Newcastle, England. NITRATE OF SODA.- Nitrate of soda is used as an oxidizing agent in the "batch", and is therefore a decolorizer, though the soda enters the composition of the glass. The chief source is the beds in the province of Tarapaca, Peru ; but some immense deposits have also been found in Nevada. POTASH. The use of potash in glass-making is comparatively recent, though some of the best and most expensive glass now made, such as the Bohemian white and the English flint, are potash glasses. Some few specimens of ancient glass show small quantities, from 1 to 2 per cent., which was probably derived as a chance material from the sodas prepared from plants and weeds, in which some potash is always present. As early as the fifteenth century, if not earlier, the value of potash as a glass-making material was known, and it appears that at that time potash made from the lees of wine was used in the Venetian glass houses. In France, in the middle ages, potash made from fern was used. The enormous forests of America began very soon after the discovery of this continent to furnish large quantities, and enormous tracts of timber have been burned solely for the ashes. Blancourt, at the close of the seventeenth century, speaks of the use of potash from wood-ashes, and mentions Virginia and New England as sources of supply for the latter. The sources of supply at the present time are many. Much of that used in modern glass houses is still made from wood-ashes, about 20,000 tons being thus produced annually, the Canadas and Eussia furnishing the larger part, though the Bohemian glass manufacturers procure theirs from the forests of Bohemia and Hungary. This potash, as it is made by lixiviating wood-ashes, is an impure carbonate, which must be calcined and refined, the quality of the glass depending upon the degree of purification. Refined potash is known as pearlash. Pure carbonate is also obtained from the alkaline residuum of the manufacture of nitric acid and from caustic potash. In France beet-molasses and the ashes of beet-cake and grape-cake have considerable value as sources of potash, some 12,000 tons per annum being made in Europe from the beet alone. Carbonate of potash, the form in which it is used in glass-houses, is also prepared artificially from the sulphate by Leblanc's method. Of the remaining salts of potassium, only tartar, the bitartrate of potassa, which is decomposed, when heated, into carbonate of potassium and carbon, finds sporadic application where it is required to use the finely-divided carbon of decomposed nitrate of potash as a reducing agent, for example, in the production of copper, ruby-glass, or ruby-fluor. The sulphate of potassa, though applied as long ago as 1826 by Long, in Constein, on the Danube, has never yet attained to general importance in the glass industry. LIME is, next to silica, the most important of glass-making materials. It is a constituent of nearly all the glass of all ages and countries, with the exception of that made with lead, and it is even present in many specimens of lead glass, though, as before stated, its presence in ancient glass was probably by chance and not by design. The action of lime is to render the soda or potash glasses harder and less soluble, and, when used in the proper proportion in the "batch", to promote the fusion of the materials and improve the quality of the glass. An excess of lime, however, makes the glass too hard. In the manufacture of table ware lime furnishes a cheap substitute for lead, and, though as a rule the lime-flint is less brilliant than the lead-flint, many of the recent specimens of lime glass, especially those that are "fire-polished", are exceedingly beautiful, approaching in brilliancy the true crystal of the English flint houses. The makers of lime glass, however, do not, as a rule, seek to compete with lead gltiss in brilliancy, but in lightness and beauty of form, as is the case with the Bohemian glass- workers, or to furnish a cheap substitute for lead glass for articles of utility, as is the case with the pressed-ware manufacturers of this country or the manufacturers of " Gobeleterie " of France. Lime also enters largely into the composition of modern plate- and window-glass, giving it the hardness and insolubility necessary to protect it from the weather and prevent its " sweating", which is so marked a fault of glass with an excess of alkali. USE OF LIME A MODERN DISCOVERY. Though the true relation of lime to the manufacture of glass as a hardener and preserver is really a very modern discoverv, and though the proper proportion of lime to soda and 1070 MANUFACTURE OF GLASS. 33 potash has only been arrived at slowly and by many careful experiments, it is true that it was used to some extent in the glass houses as early as the days of Pliny. He says : To the materials of glass they begin to atld the magnetic stone ; then they joined shiny stones of all kinds : then shells and fossil Bands. He also notes that the use of lime in his time was an advance in the art of glass-making. Ferrantes Imperatus recommends the shells of cretaceous fishes, as the oyster, as "very proper for making glass". Notwithstanding these indications that the use of lime was not entirely unknown from the time of Pliny, it has been but recently that its value as an essential constituent of glass has been recognized. Blancourt was somewhat afraid of it, and declares that " it is much stronger than ordinary salt ", but directs that it " being well purified you may put two pounds of it to an hundred pounds of salt of Polverine", or soda. He would think the glass-makers of to-day, who, in some forms of glass use measure for measure, must be gnided by " parcimony", of which he elsewhere speaks. It is probable that until very recently lime has been used only as a cheap substitute for soda and potash, the difficulty of using it in furnaces, constructed and heated as the older furnaces were, interfering with its adoption, until recent investigation had shown its value and recent improvements had made its employment possible. SOURCES OF SUPPLY. It is unnecessary to speak of the sources of supply of lime, as all glass-making countries have it in abundance, and it is used in the batch as chalk, lime, or limestone. Lime, however, that contains ferrous carbonate of iron must not be used in a mixture intended for white glass. Indeed, except for bottle-glass, it is important to have the lime, as well as all the other materials, as pure as possible. Mr. Chance notes that glass made with limestone is harder and more difficult to grind than that made with chalk, and it moreover causes the glass to cool anil set more rapidly. In this country, however, limestone is coming into more general use, some of the Pittsburgh window-glass works using no lime at all, but only powdered limestone. 'LEAD. The use of lead as a glass-making material, except in the production of artificial gems, is an English invention of the seventeenth century, (a) and grew out of the use of mineral fuel in the glass houses of that country in the place of wood, which up to that time had been the fuel of glass- making, as it still is in many sections of the world, (b) This fuel required covered pots to protect the glass from impurities, which so reduced the amount of heat that reached the materials as to demand a better flux, and lead was substituted. The result was not only to permit the use of the cheaper fuel, but the production of that most beautiful and brilliant of all glasses, the English flint. Lead is used both as litharge and as red lead, and is a most powerful flux, promoting the fusion of materials at a very low temperature. The glass made with it is more dense, has a greater power of refraction, and is k-s.< liable to breakage from sudden changes of temperature. It is soft and is easily worked and scratched, but is of surpassing brilliancy, being only excelled by the diamond. The glass used for the manufacture of artificial gems is a lead glass, and it is to the employment of this material that they owe their brilliancy, while at the same time an excess of lead renders them soft and easily scratched ; a fact that soon becomes apparent to the wearer of these gems. It is very probable that the use of lead in a small way in the manufacture of these gems, which antedated its use in flint glass, was the suggestion to the English that resulted in the discovery of the latter. Lead is also used in the manufacture of optical glasses, and the history of its use for this purpose is exceedingly interesting, but cannot be repeated here. LEAD GLASS, WHERE MADE. Lead is used in the manufacture of glass to a greater extent in England than anywhere else, though France and Belgium, and, to a less degree, Germany, make some true lead flint. In this v'uuntry lead glass is made but to a limited extent. Some few factories still make lead-flint table ware and liimneys, but most of the table ware is lime glass. In the past, however, considerable lead glass was made here, and red lead of an excellent quality for glass is still made at East Cambridge, near Boston. The first lead furnace in the L'nited States is believed to have been built by Mr. Deming Jarves, of the Xew England glass works, East Cambridge, in 1818, for the manufacture of lead for glass. This furnace was a success, and enabled the company to continue the manufacture of glass at a period when no foreign red lead was to be procured, (c) Eed lead is generally preferred to litharge on account of its finer state of subdivision, and because its decomposition in the glass pot assists in purifying the materials, as an excess of lead not only makes the glass soft and gives it a yellowish tinge, but acts injuriously upon the melting vessels. OTHER INGREDIENTS. Among the other ingredients found in glass are the following: Iron, which is almost always present in several of the materials, especially sand, and is a most unwelcome element, imparting a greenish color to the glass. Manganese in the form of the black oxide is introduced to correct the action of the iron, but the researches of Mr. Thomas GafSeld, of Boston, show that the action of manganese as a decolorizer is not permanent* (d) a Dr. Lardner, in his Cabinet Cyclopaedia, says : The manufacture of flint glass was begun in England in 155? at Savoy House, in the Strand, and in Crutched Kriars." Bontemps, in bis Report on Glass at the Paris Exposi ion O/1855, shows that this is a mistake, so far as relates to lead flint, and states that it could not have been made prior to 16. 6 It seems that lead was used in the manufacture of glass much earlier than this, certainly in the Roman period ; but it is still true that the English are entitled to the credit of its first use in lead glass as now made. c Reminiscences of Glass Making, second edition, page 110. d This >s probably the " magnetic stone" of Pliny, and its use as a decolorizer has been known for centuries. 1071 34 MANUFACTURE OF GLASS. Carbon in the form of powdered charcoal, coke, or anthracite is used in " batch " of sulphate of soda to facilitate the decomposition of the sulphate. Arsenic promotes the decomposition of the other ingredients and the removal of carbonaceous matter. In excess, however, it produces milkiness. Alumina is almost always present in glass, generally from the action of the materials of the glass on the pots. Gullet is the waste glass produced in every manufactory, which, being more fusible than the new material, facilitates the melting. CHAPTER V. GLASS FURNACES AND POTS. EARLY FURNACES AND GLASS HOUSES. But little is known regarding the form or construction of the furnaces used by the earliest glass-makers. One of the paintings at Beni Hassan, one of the earliest records of the art remaining, pictures an Egyptian glass-melter seated before an upright circular furnace about 2 to 3 feet high and one-third this in diameter, from which he is evidently gathering the molten glass through a square hole at the bottom. This would indicate that the glass materials were charged at the top of the furnace and drawn at the bottom: an operation somewhat analogous to smelting iron, but one that would give very impure glass. If this was the practice of the early glass-makers, this method probably gave place at an early day to a crucible of some kind, in which the materials were melted, the heat being applied outside and fuel not being in. direct contact with the glass. It is quite certain that the early glass-making furnaces contained until long after the beginning of the Christian era but a single small pot, the entire work of mixing, melting, blowing, and finishing being done at each little establishment by a single glass-worker, assisted in the earlier and less skilled part by slaves or servants, and the minute division of labor which is so distinguishing a feature of modern industrial life, and the aggregation of capital and workmen in one large establishment, were unknown in these early days, especially in industries in which so much depended on individual skill, and where the art was regarded as a mystery or secret not to be divulged. The great variety in form and character, and especially in the color of the glass of these works, as evidenced by the very many fragments remaining, would also indicate that glass-making was carried on not in large establishments, producing, as at the present day, quantities of glass of the same form and color, but in many little establishments, each working on a small scale, and each producing glass differing in color and shape. FURNACES IN AGRICOLA'S TIME. Though we have but little knowledge of the early glass furnaces, it is well known that those of four hundred years ago did not differ much in principle or in construction from the ordinary direct-firing furnace of to-day. The description given by Agricola, one of the earliest of modern writers on glass, of the furnaces used at the beginning of the sixteenth century is so near like that given in Dr. Lardner's Cabinet Cyclopaedia of fifty years ago that the latter can almost be regarded as a translation of the De Re Metallica. Agricola describes three forms of furnaces as in use in the glass houses of his time. In the first, called the " Fornax Calcaria ", a small furnace somewhat resembling a bee-hive coke oven in shape, the materials were dried, purified so. far as they could be by heat, and partially combined in a cindery or slaggy mass called "frit", which was afterward broken up and remelted in working furnaces. The greater purity of modern materials and the better methods of working have made this preliminary purifying and "fritting" unnecessary, and the term "frit" is now applied to the unmelted mixture of sand, soda, lime, etc., which is charged into the pots, or, in other words, to the "batch". Fifty years ago, however, this process of fritting was still in use. At the present time the calcar furnace or arch is only used to dry and calcine the sand, unless it may still be retained in some glass-making sections where the old methods are still in vogue, or as an annex to the bottle furnace, where impure materials are used. In some cases the calcar arch is used to heat the "batch" prior to "filling in", it being thought better to charge it heated into the hot pots. Agricola's second furnace was the melting or working furnace. I quote the description of this as given by Blancourt, with his comments and improvements : (a) The second furnace or oven Agricola mentions is that where the workmen labor, or the working furnace ; but the description he gives us of it is not just, for he makes all these ovens round, whereas they ought only to be round withiu, but oval without. Moreover, h adds two mouths in form of chimneys, wherein a servant throws coals day and night, which is no more now in use, since we only use dried wood, as I have observed, which also makes the iron grates he mentions for the mouth and ash-hole of no more use among us. This oven, whose diameter ought to be always proportional to the height, is divided into three parts, each of the three parts being vaulted. That below is the place where the servant flings in the wood to keep a continual fire, and without smoke ; and this lower oven is called the crown, and tho mouth the Bocca ; but there is neither grate nor ash-hole, the wood being cast in on the coals, care being taken to take them out whom there are too many with a great iron hollow shovel. This oven, made like a crown, to which Agricola allows but one hole in the middle a See Rlancourt, Art of Glass, London, MDCXCIX, pages 20-23. MANUFACTURE OF GLASS. 35 of its height, about one foot in diameter, has, notwithstanding, several holes all round it for vent of the flame, which ascends into a second oven through the middle, where are placed the pots filled with the ingredients that make tie glass, npon which that flame perpetually reverberates. The second part of this oven, whereof the vault is round, serves for the workmen. Agricola allots to each of these ovens eight arches; nevertheless we commonly make bnt six. Between each arch there is an opening or hole, made in fashiou of a window, archwise called the great work-hole, through which the pots are pnt in and those taken out which contain tlie metal. These great holes are stopped each with a cover made of the same Inte and brick that the oven is, to preserve the workmen's eyes from the too vehement heat and likewise to keep it the stronger in the oven. In the middle of every one of these covers there is a hole somewhat more than a palm wide, which is called the little working-hole, through which the workmen take with their hollow irons the colored or finer metal out of the pots, wherewith they make what sort of vessels they please. It serves also to scald their vessels \vheu they have occasion, and which rest upon hooks made on purpose on the sides of those holes, which are called, according to their term.-, the little \\orkiug-holes, The upper vault <>f this furuaee, which is above that where the metal is melted and the workmen work, servos to put the vessels that are new made npun. there to eosl by degrees, that place having only a moderate heat; otherwise the vessels would break if they were too soon exposed*to the cold air. We might also divide that upper vault into two, the half of it being enough for ending the vessels; and on the other might be made Holme Maria:, of diverse degrees of heat, sand furnaces, or of ashes for purifications, digestions, distillations, andother uses and may serve for the preparation of the ingredients wherewith we make tinctures for glass and crystal, whereof we shall treat in the sequel oi this book. The ovens of the great glass houses are round within and oval without, like those of the little glass houses whereof we have already made mention ; but there is this difference : that any ingenious workmen can build those of the little glass houses, but there is only one race of masons iu all France who have the secret of building the great ones. They came from Caule, in the county of Eu, and those only can succeed iu it. What and how nice observations soever others have made to imitate them, there was never any one yet could arrive to it, insomuch that all those who have any great glass houses throughout the whole kingdom are obliged to have recourse to that family to build their furnaces, ami that for want of a due proportion which must be observed, because they must have three degrees more of heat than the little glass houses, ami one inch difference in the arch and body of the oven is enough to spoil the whole process. These ovens are built like those we have before mentioned, except as to the proportions which angment the heat three degrees beyond the others; they have six arches two of which serve to heat the matter before you put it in the pots, and another to heat the pots before you pnt them into the oven when there is occasion to change them. In this oven each working-hole has bnt one pot in it, and in the farther end ofthe oven on the other side of the workmen there is a great pot. wherein the matter (or ingredients) is prepared, out of which you take it with an iron ladle of 10 or 12 feet long, to fill the pots of the gentlemen who work at the rate the pots are emptied ; after that the great pot is filled again with other matter to be refined and prepared as before. The materials which serve for building these furnaces are bricks for the outward parts, and for the inner parts a sort of fuller's-earth, which is gotten from Beliere, near Forges, and which is the only earth in France which has the property of not melting in this excessive heat; and it is of this same earth that the pots are also made, which will hoi 1 the melted metal for a long time. It will be noted that this oven of Agricola and Blancourt is virtually the direct-firing wood or coal furnace of to-day with the upper part above the reverberating arch used as an annealing oven. This third division is still in iiw in Bohemia lor the same purposes as described by Blancourt. 3IuDKi:x KTHXACKS. The glass-melting furnace of modern times is a modified form of the reverberatory furnace, which assumes different shapes, and is built of different sizes, according to the kind of glass to be made or the fuel used. Furnaces for plate-,wiudow-, aud bottle-glass are generally oblong or square, the pots being placed in two banks or rows, one on each side, while those for flint-glass are circular or elliptical. In the construction of furnaces the principal ends to be attained are the production and maintenance of an intense heat, (a) its uniform distribution through the furnace and around the pots, and its direct and most intense application to the fusion of the glass-making materials. Without entering into a detailed description of the varying shapes and sizes of the ordinary furnace iu use in this country, it may be said in general that these furnaces consist of two parts, the combustion or melting chamber aud the cave or ash-pit, which also serves as a draught passage. These are separated by the fire-grate and "siege", the raised bank or narrow platform in the melting chamber on which the pots are placed. The grate or fuel-space is square, and occupies the center ofthe furnace, and the fuel is charged generally from both ends. The grate is usually on the same level as the floor of the glass house. Under, and connected with it, is the arched subterranean passage or chamber kuowu as the cave or ash-pit, extending the entire length of the furnace, both ends opening outside the building, thus forming a passage by which air for combustion is fed to the grate. Sometimes two of these passages, crossing under the grate-bars at right angles to each other, are built, so that either can be used according to the direction of the wind. There are doors at both ends of these archways to regulate the draught. Within the furnace around the grate space in the case of circular furnaces, or on both sides of it in quadrangular furnaces, is the raised bank or platform termed the "siege", on which the pots are placed. The fire thus lies below the bottom of the pots and in the center of the furnace. The number of pots in a furnace varies from four to eighteen or more. Each pot is reached for charging or working the metal by a small arcbed opening or working-hole in the side of the furnace, situated directly over the pot, except in the flint furnace, where covered pots are used. In this case the mouth of the pot is on a level with the working-hole, and the number of working-holes in a furnace thus equals the number of pots. Furnaces other than flint frequently have no chimneys or flues, the only exit for the products of combustion being the working-holes. As the fire is in the center, and the pots are around the sides, the flame is thus made to play around the pots, securing a most direct and intense heat. In some furnaces, however, there are as many flues or chimneys as there are pots, the flues a There is a wide difference of opinion as to the heat of a glass-melting furnace. Sauzay, in Wonders of Glass Making in AH .Iget, New York, 1673, states it to be 1,000 to 1,500 C. The Encyclopedia, of Chtmiitry. Philadelphia, gives the proper temperature of a glass furnace at '20,000 F. This last figure is doubtless a "guess", and it might as well have been put at 50,000. Mr. Page, of the Berkshire (Massachusetts) "lass works, gives the heat of a glass furnace as between 2,800 and 3,600 F., or an average of 3,200. (W M il lu73 36 MANUFACTURE OF GLASS. being placed between. The same result, however, is obtained, the flame striking the pots on its way to the flues. Furnaces are often constructed with a double arch, the lower one the reverberating arch, the upper one forming the top of the furnace, and the space between the two arches forms a chamber for the reception of the products of combustion, which pass out by a common flue at the top. Frequently, instead of this outer arch, the outside walls of the furnace are curved up in the form of a truncated cone or open chimney, and in others the separate flues open into the glass house itself, which thus becomes a chimney, discharging the products of combustion at the top of the house. The roof of the furnace is arched, the arch being built as low as is consistent with stability, in order to reverberate or throw the heat with the greatest intensity upon the pots. The inside dimensions of these furnaces vary so much that it is possible to give only a general idea of their dimensions. A ten 44-inch pot window glass or green-bottle furnace would be about 20 feet long by 12 feet wide ; a ten 36-inch pot flint furnace about J2 to 13 feel; in diameter, the materials used being fire-brick or sandstone, or both. FUEL USED. The fuel used in the early glass houses was wood, (a) which was dried or baked to expel all moisture before using. In view of the fact that even at the present time it is difficult to secure the intense and even temperature necessary to properly melt and "fine" glass with wood, the success of the ancient glass-workers is all the more commendable. It is possible that when only one pot or crucible was used this may have been surrounded with charcoal, and a more intense and even heat produced than with wood ; but when furnaces with more than one pot became common, and the glass was thus melted by the flame playing on the pots, it would greatly increase the difficulty of melting with wood, and preclude the use of charcoal. It is generally stated that mineral coal was first used in England in glass-making in 1635 by Sir Robert Mansel, who obtained a monopoly of the manufacture of flint-glass in consideration of his being the first person who employed pit-coal instead of wood in his furnace. This, however, is not correct. Blancourt states : In the time of Agricola they made use only of coals in the glass houses; but the use of wood, which is among the moderns, is much better; for, being first of all thoroughly dried, it does not smoke like coal, which always makes the glass dull and obscure. . \ As Agricola published his De Re Metallica in 1546, Hansel's claim to being the first to use pit-coal can hai'dly be sustained. Indeed, it is disproved by the English records themselves, as before 1611 Sir William Slingsby had obtained a patent for making glass with sea-coal ; and in 1615 a royal proclamation was issued prohibiting the use of wood in glass-making and ordering it to be made with sea- or pit-coal only. Sir Robert seems, like many a reputed inventor, to have filched the honor belonging to another. In England at the present time coal is almost exclusively employed, but of late years it has been found that oven-burned coke can be used to advantage, as it produces less smoke and soot, and is therefore better adapted to some of the finer glasses. In France both coal and coke, and sometimes wood, are used. Belgium uses coal exclusively. In Germany wood is largely employed, beside considerable peat and turf. Both coal and lignite are also used. Where wood is used, it is baked until brown, to expel all of the water, and peat must also be dry and afford only a small amount of ash. In this country coal is used almost entirely, though as late as 1865 wood was still used in Boston. It was the excellent quality of the coal at Pittsburgh that led to the erection of the first works in that city. GAS FURNACES. So far the description and remarks concerning furnaces apply more properly to what are known as "direct-firing" furnaces, or those heated by fuel charged directly into the fire-pot or hearth of the furnace. In 1861 the first successful gas furnace for glass, the now well-known Siemens furnace, was first used. In this and other forms of the gas furnace the solid fuel is first converted into gas in a producer outside of the furnace, and is then burned, generally in connection with heated air. This application of gas is one of the most marked and important improvements in glass-making of modern times. Beside the saving in fuel and the possibility of using inferior fuel which the gas furnace permits, it reduces the time of melting and increases the production as well as greatly improves the quality of the product. THE SIEMENS' FURNACE. The first use to which the Siemens' regenerative gas furnace was put, now so well known in all parts of the world, was the manufacturing of glass in pots. In using this furnace the principle and construction of the ordinary furnace were changed only so far as was necessary to apply the regenerative principle and heat with gas. In these furnaces the gas and air em ployed are separately heated by the waste heat from the flame by means of what are called " regenerators" placed beneath the furnaces. These are four chambers filled with fire- brick, stacked loosely in checker- work, the waste gases passing through one pair of regenerators and heating them, while the air and gas are being heated, prior to burning, by passing through the other pair, which had been similarly heated.. When this second pair has been somewhat cooled the direction of the draught is changed, the waste gas passing through the cooled pair, heating them, while the air and gas are passing through the heated pair. This is again changed when the regenerator is cooled, and so the cool air and gas are passed alternately through each pair of regenerators, which are thus alternately cooled and heated. The economy of fuel is not only great, but the heat produced is intense, and actual working, it is claimed, shows a saving of 47i per cent, of fuel over the direct-firing furnace in glass-making by the use of this furnace, (b) The loss in pots is reduced ; and there are no " cutting drafts " a Plutarch states that " tamarisk wood is the best for the glass furnaces". 6 The saving of fuel in gas-firing is stated never to be less than 30 per rent., and is often as !ri<;li as7."> per cent. 1074 MANUFACTURE OF GLASS. 37 on the outside, the pots only cutting from the inside. The durability of thefurnace is also increased, table shows the extent to which these furnaces were used in 1879 : SIEMENS' FURNACES USING POTS. The following Window- Countries. Plate-glass, and liottle- glas.%. Flint- glass. Great Bri1 sou .. ; : : ,: 15 Other com i tries SIEMENS' FUENACES WITH TANKS. Great Britain - 6 SIEMENS' FURNACES WITH CONTINUOUS TANKS. Great Britain 4 France 10 Belgium 1 Other countries 3 USE OF SIEMENS' FUENACES IN THE UNITED STATES. Though, as this table shows, the Siemens pot-furnaces are used to a considerable extent in all glass-making countries of Europe, but few have been built at the glass houses of this country. One reason, no doubt, is that good coal is so cheap at our glass-making centers as not to make economy of fuel a necessity, and in addition to this the heavy first cost of the furnace and the royalty asked have interfered with its adoption. Their use in this country during the census year was confined almost exclusively to plate-glass works. Other forms of gas pot furnaces, however, have been recently introduced to some extent, especially in the vicinity of Pittsburgh. These are known locally as the Nicholson and the Gill furnaces. Of the principle of the former I have not been able to secure any description ; but it is an improved form of a French furnace, and differs from the Siemens in not having the alternate regenerators. The dimensions of one built in 1880 for Messrs. MeKee & Bros., glassware manufacturers of Pittsburgh, were as follows : Height of stack, 80 feet ; diameter at the foundation, 22 feet 10 inches; in the furnace at the floor, 18 feet 10 inches in the clear, and contains 12 pots, each 44 by 60 inches, of a capacity of 3,800 pounds each, or 45,600 pounds at a single melt. It is expected to make four rounds and a half per week, equal to 102J tons of metal. There are three large gas-producers, in which ordinary coal dust or slack, a very cheap material, is used. The so-called Gill glass furnace is an improvement on the Boetius principle, which has been so successfully used in Germany. This furnace has flues arranged around the outer walls of the fireplace, or in the walls between the fireplaces, for the purpose of conveying air to the combustible gases evolved from the fuel. It is claimed that its original cost is much less than the Siemens or any other form of gas furnace ; that the direct-firing furnaces can be remodeled ; that the heat received is inteuser, more uniform, and is more easily controlled, while the quantity of fuel is much reduced below that of the ordinary furnace, and an inferior quality can be used. The life of the pets is also greater. COMPAKTMENT OB TANK FURNACES. While the application of gas to pot furnaces marks a most important advance in glass-making, the invention of the tank furnace and its use with gas is a still more important and marked improvement, and promises to have a great influence on the future of the industry. In this furnace the use of the melting-pot is entirely abandoned. In the first Siemens tank furnace of 1861 the batch was charged, melted in, and worked from a tank which occupied the whole bed. This in use was found to have some drawbacks, and in 1872 a still further development of the tank furnace was effected by dividing the tank, by means of two transverse floating bridges, into three compartments, in the first of which the batch was melted, in the second the glass was refined, while the third held the thoroughly purified glass, from which it was worked out continuously. These floating bridges, however, were rapidly destroyed by the heat of the molten glass, and a still further improvement, which has largely increased the melting capacity of the furnace, has been made by the substitution of a floating refining vessel in place of the floating bridges. In this latest form the batch is charged from time to time through a door at one end of the furnace. The glass, upon melting, sinks and travels on toward the gathering holes, at the other end, in a partially refined condition. Opposite each gathering hole a refining vessel is floated, which gathers the molten glass at the lowest possible depth in the tank and raises it to the surface to be completely refined in a compartment prepared for that purpose, from whence, ou sinking, it can only flow into the . working-out compartment. From this last compartment the glass may be worked out continuously, the flow of the metal therein, and its assortment in the different stages of its manufacture, being entirely effected by the varying densities of the particles subjected to the heat of the furnace. Owing to this important feature it will be seen 1075 38 MANUFACTURE OF GLASS. that only the best glass, which is the heaviest, can reach the compartment of the vessels from which it is to be gathered, the imperfectly-melted metal remaining in the tank as long as needful for proper fusion. The refining vessels are made of pot-clay, and vary somewhat in size and form, according to the character and quality of glass intended to be produced. The gathering compartment is sometimes made entirely open, sometimes covered wholly or partially with a hood ; but in all cases the vessels are floated on the metal in the tank, and are constructed so as to be easily removed when worn out. By the employment of these refining vessels dividing bridges in the tanks are no longer required, and thus that part of the structure which in the first forms of continuoas glass-melting furnaces was subject to the most wear is done away with. Another advantage is found in the circumstance that the ends of the blowing-canes, which sometimes break off in the glass, may be easily picked out from the bottom of a refining vessel, instead of its being necessary from tune to time to empty a tank, in order to remove as useless the glass discolored by the accidental introduction of iron. The color of the glass made in a tank may be altered from time to time, as required, without interrupting the blowers ; and for this purpose it is only necessary to cease charging batch into the furnace for a few hours, when some of the new glass mixture is introduced, and further charges are made at regular intervals. According to the productive capacity of a tank, the change of color will be effected in from three to five days, and only a few hundred -weight of mixed metal is formed, which has to be ladled out. For works requiring the regular production of glass of different colors or characters, in insufficient quantities of each sort to warrant the erection of a special furnace for each variety, the tank may be divided into two or more compartments, or several large pots may be set in a furnace, each of which shall have the desired number of refining vessels. By surrounding these pots with sand they will be much strengthened, so that they may be made larger than usual, and thus form several small tanks in one furnace, which can easily be removed when required. In this manner the continuous melting process may be applied to both large and small productions, and will therefore be of interest to all glass manufacturers. The principal advantages resulting from the use of the continuous-melting furnaces are claimed to be : 1. Increased power of production, as the full melting heat may be employed without interruption, while with the old method of melting nearly one-half of the time is lost by cooling and settling the metal, the working out of the glass, and the reheating of the furnace. 2. Economy in working, as only one-half the number of men are required for the melting operations. 3. Durability of the furnaces, owing to the uniform temperature to which they are subjected. 4. Regularity of working and improved quality of the glass made. 5. Convenience to the men and advantage to the manufacturers, as owing to the continuous action the metal is always ready for the blowers, and the gatherers can draw the metal from a practically constant level. 6. For the manufacture of window-glass the working-out end of the furnace may be so arranged that the blowers can work without interfering with the gatherers. This would do away with the. separate blowing furnace now in use. The greater durability of the tank is not only due to the uniform temperature maintained, but also to the circumstance that the batch is charged iu such quautities at a time as not to come into contact with either the sides or the bottom of the tank, which, consequently, are not suddenly cooled or eaten away by the mixture. Furnaces containing as few as four gathering-holes, while others of greater capacity up to thirty-two gathering- holes are now in operation, the latter being worked with a consumption of one ton of lignite per ton of glass bottles produced, which, having regard to the calorific power of that fuel, is equivalent to the small consumption of 10 hundred- weight of coal to the ton of glass melted, molded into bottles, and annealed. As showing the results obtained with the second style of tank we give the following statement from one of Mr. Siemens' pamphlets, showing the work done during five consecutive weeks in a continuous tank furnace by one of the extensive glass manufacturing companies of England. It should be noted that at the time this statement was taken the furnace was working but two shifts out of the twenty-four hours, whereas it can be as readily worked continously three shifts in twenty-four hours : Week ending- COAL UBED. BOTTLES DECLARED. ' Number of chairs used on all shifts dur- ing the week. Declared bottles per cliair }>er lift. BOTTLES DRAWN. PER TON (2,240 POUXD8) OF BOTTLES DBAWN. Producers. Kilns. Total. Batch. Dozen. Weight. Dozen. Weight. Coal in pas-pro- (Ulcers, exclusive of kilns. Total coal, in- cluding Kilns. Batch. February 19, 1875 Pounds. 90, 720 84,000 80,640 73, 920 78, 400 Pound*. 26, 880 26, 880 26,880 26, 880 33,600 Pounds. 117, 600 110, 880 107, 520 100, 800 112,000 Pounds. 70, 000 101,360 84, 000 88, 480 112, 000 3,873 4,124 4,057 4,450 4,960 Pounds. 55, 272 58, 406 57, 008 66, 276 67, 872 40 40 40 45 49 96.8 103.1 101.4 98.9 * 101. 2 3,698 3,867 3,733 4,070 4,609 Pounds. 51, 828 54, 600 52, 416 56, 364 62,608 3,942 3,449 3,427 2,912 2,800 5, 017 4,547 4,592 3,987 3,987 3,146 4,144 3,584 3,516 3,987 February 26 1875 March 5 1875 March 12 1875 March 19, 1875 1076 * One chair missed a journey. MANUFACTURE OF GLASS. 39 The accompanying diagrams, from drawings kindly famished me by Messrs. Eichmond & Potts, of Philadelphia, give an idea of this furnace, Figs. 1 and 2 showing a four- or six-hole window-glass furnace, which at any time Jtig.l. may be doubled in capacity by adding the same number of blowing- and gathering-holes at the other end and charging at the center. These double-end furnaces are in use in Europe with the best satisfaction. No Siemens' tank furnaces were in operation in this country in the census year. One was building at Poughkoppsie, and has since been started, but not with very good results. One has since been built in Illinois, and its operation has been attended with good success. A number of tank furnaces of various designs were in operation or building during the census year, however. These furnaces were generally oblong, resembling an iron-puddling furnace in construction and operation, or were simply a large round pot. I have no specific details of their construction or operation, but they seem to have been quite successful and economical. POT-CLAY. The pots used in melting are made from certain varieties of fire-clay, termed pot-clay, from its use for this purpose. The clay adapted to the manufacture of pots should be as pure as possible, and be very refractory, breaking with a clear, smooth, bright fracture, unctuous to tlie touch, free from lime and sulphide of iron, and the less oxide of iron the better. The shale or slate-clay from Stourbridge, England, which is brown in color, has a wide reputation, and is largely used in British glass houses, but the foreign clays most generally employed in this country are German, though American clnys are, to a large extent, taking the place of the foreign. The clays most largely used in the European glass houses are those from Forges-les-Eaux, in France; Andeunes and Xiinmr, in Belgium; Stourbridge, in England; G!eu-borg, in Scotland; Sargenau, in Switzerland; Schwarzenfell, in Bavaria, and Klingenthal, in Germany. In this country there arc large deposits of excellent pot-clays in many localities. Those that are used, however, are chiefly drawn from western Pennsylvania, Missouri, and New Jersey, though the clays of Maryland. Ohio, and Indiana are to some extent used. When America-! clay was first used it did not give the satisfaction that its analysis would indicate. This was owing to lack of skill in its 1077 40 MANUFACTURE OF GLASS. preparation, but as this has been acquired American clay is rapidly gaining in favor. Mr. Thomas Coffin, of Pittsburgh, one of the oldest pot-makers of this country, writes me regarding the use and relative value of German and American clays, as follows : About three-fifths of the clay used in this country is foreign clay, principally German. Window-, bottle-, and plate-glass houses use the largest proportion of German clay, some making their pots entirely of German, others of a mixture of German and American. Nearly all the flint houses use pots made entirely of American clay, although a few mix some foreign. It is found by experience that the American (Missouri) clay will stand a more intense heat than any other, but that the German clay resists the action of the flux. better: hence the mixture of the two to overcome as nearly as possible the two difficulties. American clay is fast superseding German clay because of the hotter-running furnaces that are now being used. Our American clay is much purer than the German, and is more refractory, but not as dense. It is much less costly, however, and must eventually supersede the German. COMPOSITION OF POT-CLAY. The composition of pot-clay from different localities is given in the following table : Localities and kinds of clay. Chemist or authority. Silica, including gand. Alumina. S 2 Magnesia. Carbonate of mag- nesia. Potassa. I Sulphur. 1 I Stonrbridgo, England: Willis Per cent. 67 34 Per cent. 21.03 Percent. 2.03 Per cent. Per cent. Per cent. Per cent. Per cent. Per cent. Per cent. 8 24 Per cent 100 00 64 05 23.15 1 85 10 10 00 100 00 65 10 22.22 1.92 0.14 0.18 18 9 86 99 60 Do C Tookey 63 30 . 23.30 1.80 0.73 10 30 99 43 61 45 24 68 1 67 10 20 10 90 Belgium: Bischof 46 64 34.78 1.80 0.68 0.41 41 1 27 96 ~ f> German : D Tal Aran 46 44 36 95 1 64 69 48 Do 70.60 23.60 0.36 0.45 1.10 3.89 71 31 15.66 1 19 0.28 63 Trace. 9 70 Kerl 46 97 37.95 95 0.04 0.11 3 00 10 02 47 33 35.05 2.30 0.16 1.11 3 18 10 51 French: 55 40 26 40 4 20 12 00 American : Cheltenham, Missouri : Litton 61 02 25.64 1.70 0.70 0.08 0.48 0.05 0.45 9 68 100 00 do 59 60 26 41 1 61 1 00 07 29 16 38 10 48 100 00 Dixon, Missouri : 56 02 28 86 1.67 1.76 0.34 11 12 Washed do. . . 55 06 30.02 1.57 2 20 0.41 10 54 Weiss 63 75 26.60 0.75 Trace. 0.85 0.40 2.25 7 40 100 00 Oak Hill Missouri 64 32 22 82 1 75 45 12 23 54 12 10 9 6 100 58 63 10 . ** * 23 70 2 20 09 06 04 08 10 73 43 88 40 96 82 Traces. 13 99 99 65 70 18 20 99 0.65 0.13 0.08 7.75 Professor Cook 59 93 26.95 1.24 0.07 Trace. Trace. 10 20 Salvetat 72 3j 16 75 1 29 2 00 07 7 98 ware. MANUFACTURE OF POTS. The manufacture of the melting-pots for a glass furnace is one of the most important, careful, and tedious of the operations about a glass works. From the digging of the clay till it is refined, mixed, kneaded, and built into pots, and these are thoroughly dried, heated, and set in the furnace, two or three years often pass. The pots themselves are costly, the setting difficult and expensive, and if they are improperly made or spoiled in drying, heating, or setting, and break, the entire batch frequently is lost, and in many instances consequential damages ensue from the delays and loss of output. The importance of having good pots is so great that many manufacturers are not willing to depend upon outside makers to supply them, though this opposition to outside pot-makers is not so great as it was a few years since. It is estimated now that about one-half of the pots used in the country are not made at the glass works. The clay, having been allowed to ripen or putrefy a sufficient time, is mixed into a thick paste with water and from one-fifth to one-fourth its weight of finely-ground old pots or "potsherds ", and is thoroughly kneaded by tramping until it is of the toughness of putty. This mixture dries more rapidly, contracts less when drying, and better resists the action of the fire and materials of the glass than the pure clay. The kneaded clay is then made into long rolls and built up by hand, little by little, into the solid compact pot, no machinery being used, and care being taken to keep it free from air cavities. The pots are not built up at once, but after placing a layer, each pot is permitted to stand and set, being kept carefully covered. A good pot maker and his assistants can furnish one pot a day. After the pots are made, great care is taken to 1078 MANUFACTURE OF GLASS. 41 dry them thoroughly. In summer the natural temperature is sufficient, but in winter they are kept at from 60 to 70 F., care being taken not to allow them to freeze. The pots are allowed to dry from four to eight months, and when they are ready for use their temperature is very gradually and cautiously increased, first in a warmer room and then in the annealing arch, until they reach the temperature of the working furnace, when they are immediately placed in the furnace or "set". Tke soundness of the pots is tested by throwing a small lump of coal against the side. If it rings well, it is regarded as a good pot; but if dull, it will probably be short-lived, though this test is not always conclusive. THE SETTING OF THE POTS is one of the most difficult and laborious of the operations at a glass Avorks. Mr. Henry Chance remarks: The terrible task of setting these pots in the furnace falls upon the glass-house crew, and the nicety with which these enormous vessels are adjusted in their place, in tlie teeth of a consuming fire, is, perhaps, that operation which, in the many marvels of glass-making, would most astonish a stranger to such scenes. LIFE OF POTS. Tke average duration of open pots when thus fixed is about seven weeks; but some attain the age of ten or twelve weeks, while others, as every manufacturer well knows, terminate their existence prematurely, either from the naturally defective constitution of the pot, or from bad treatment in the pot arch, or, more frequently, from its having been "starved"; that is, exposed to a current of cold air in the furnace through the neglect of the attendant. Flint pots have a much longer life, averaging perhaps three months, single pots sometimes lasting ten months. In a ten-pot lime-flint furnace at Pittsburgh but 21 pots were set in a year. "Misfortunes never come singly" is an adage applicable to the catastrophes of pots, and it was truly remarked to a manufacturer, at a period when such calamities were frequent, "Your pots break because they break." The breakage of a pot often disturbs the furnace to such an extent that the breakage of others frequently follows, and many weeks will sometimes elapse before the disorganization thus produced can be rectified. The loss of a pot and the " metal " contained is nothing as compared with the injury which the glass in the surviving pots, and the pots themselves, are apt to sustain. SIZE OF POTS. The size of pots, not only in different countries but in the different works of the same country and in the manufacture of different kinds of glass, varies. The pots for the plate-glass houses of this country range from 30 to 35 inches in diameter; window-glass, from 40 to 44 inches; bottle- glass, 44 to 60 inches, and flint from 33 inches in diameter at the bottom to an oval 52 inches wide by 63 inches long at the bottom and 54 inches high. The English pots for blown window-glass are from 42 to 65 inches outside diameter ; the French 1.10 meters (43.41 inches) at top, 0.92 meter (36.223 inches) at bottom, and 1.12 meters (44.09 inches) inside height; the Belgian about 48 inches (say 1.10 by 1.30 meters); the German contain from 140 to 180 cubic feet ; and the Austrian from 500 to 600 millimeters. Flint-glass pots are generally smaller, say from 36 to 40 inches, while those used in the Bohemian glass houses are stated by Mr. Colne to hold only 160 pounds of batch. Pots for colored glass are also very small. SHAPE OF POTS. Pots for all glass but flint are open truncated cones, the smallest diameter being at the bottom. Even some flint-glass pots are used uncovered in the gas furnaces, but usually they are covered as represented in the accompanying cuts. CHAPTEE VI. MIXING, MELTING, FINING, AND FAULTS. INFLUENCES THAT DETERMINE THE CHARACTER OF GLASS. The materials for the manufacture of glass when properly mixed and ready for melting are technically known as the " batch " or " mix;", but it is impossible to lay down any standard and invariable proportion of these materials for the several kinds of glass. As has already been shown, glass is by no means a definite compound when made, and the proportions of materials are subject to even greater variations than the product. The batch not only differs for the several kinds of glass, but makers of the same kind use the materials in widely varying proportions, and even the same maker is often compelled to vary his mixture from day to day, either by reason of the varying character of his materials or the melting power of his furnace. A variation iu the sand or alkali will change the color and call for a change of the amount of the decolorizer used. When the furnace draught is good, or the furnace works " hot ", as it does on a cold, clear day, the melting is more perfect and less alkali need be used; but when it works " cold", from insufficient draft or heavy atmosphere, more alkali is needed, and the glass is inferior. To properly manipulate the melting, in view of these varying circumstances, is the work of the teaser, and his success in thus manipulating them indicates his skill. CONSTITUENTS OF THE BATCH. As indicating the general composition of the batch for the different kinds of glass in different countries we have selected the following receipts, which are given in tabular form. These must, however, be regarded as only approximate, for the reason already given, and for the further reason that manufacturers guard with the utmost jealousy tbe special composition they use to obtain the best results in their furnaces. 1(179 42 MANUFACTUKE OF GLASS. PROPORTION OF MATERIALS USED FOR PLATE-GLASS. Constituents. FRENCH. r.sGi.isn. Saint- Goblan.* Saint- Gobaiu.t No. i.; No. 2.$ Sand Pound*. 100 Pounds. 100.0 Parti. 400 Parts. 720 35 60.0 250 450 25 80 Niter 5 13.0 Chalk 30 1.0 0.5 Smolt * Authority : Knapp. t Authority : Bastinaire. J Authority : Pellatt. 5 Authority : Lippincott's Cyclopedia. PROPORTION OF MATERIALS USED IN WINDOW-GLASS. Pittsburgh * 1 KKNril. ESGLISH.t No. l.t No. 2. 1 No. 3.; No. 1. No. 2. No. 3. gand Pounds. 8,000 Parti. 100 Parts. 100 Parts. 100 Pound*. 500 Pounds. 448 Chat. 16 2 200 44 58 to 75 63 17 1.25 28 to 35 119 168 5 S" 500 6 13 to 15 Chalk 35 to 40 154 146 5 40 4 4 5 to 55 no 20 2 2 0.25 * Authority : Pittsburgh manufacturers. t Lippincott's Cyclopaedia. {Authority: Dumas. PROPORTION OF MATERIALS USED FOR FLINT (LEAD) GLASS. [The usual rule for flint glass is expressed 3 : 2 : 1 or 3 of sand, 2 of lead, and 1 of potash. ] FRENCH. Optical, t No. 1. $ No. 2. [| Sand Pound*. 1 500 Partt 336 Parts. 43.5 Parts. 100.0 Partt. 300 tot 224 43.5 80 to 85. 215 500 112 10.0 35 to 40. 110 Niter 2 to 30 Saltpeter 150 14 to 28 3.0 10 4 to 12 oz. 0.5 12 14 7 Authority: Pittsburgh manufacturers. t Authority : Pellatt. J Authority : Bontemps. Authority : Loysel. || Authority : Dumas. PROPORTIONS OF MATERIALS USED FOR FLINT (LIME) GLASS. [Sometimes a few hundredths of saltpeter, borax, and red lead are added.] Constituents. Pittsburgh.* Bohemian.t French. J Lime- white, t Clear white, t Chemical, t Sand Pounds. I 500 Parts. Part*. 300 Partt. 100 Partt. 100.0 Parts. 100.0 100 00 60 00 30 65.0 41.4 500 . 170 150 75 18 6 17.5 Chalk 8 00 0.75 0.5 Charcoal 10 Arsenic 200 1080 'Authority: Pittsburgh manufacturers. t Authority: Lippincott's Cyclopaedia. {Authority: Coins'. MANUFACTURE OF GLASS. 43 PROPORTION OF MATERIALS USED TOR BOTTLE GLASS. Constituents. Pittsburgh.* French, t English. ; Belgian, t Pounds. 8,000 Parti. 100 Partt. 100 Partt. 10 8 15 p Q h (1 2 200 20 Lime slicked 24 80 Limestone 2 400 5 Salt 250 3 80 PlftV 5 Authority: Pittsburgh manufacturers. tAuthority: Coln6. The sand contains about 20 per cent of calcareous matter. {Authority: PeUatt. MIXING THB BATCH. Upon the thorough mixing of the materials depends in some degree the homogeneity, and, consequently, the structure and value of the glass. These materials differ so much iu their specific gravities that the thorough mixing, as well as the melting, is a work of some difficulty. In this country, with the aid of a coarse sieve and shovel, the mixing is generally done by hand. Many attempts have been made to introduce mechanical mixers, but, though some are used, they have been discarded in many works, and the older method is employed. Where manual labor is as high-priced as in this country, the introduction of a satisfactory mixer would seem very desirable. In England several machines are used, that of Mr. Chance being a very simple machine, consisting of a wooden cylinder with a number of revolving oblique beaters; but Cooper's mixer is a revolving barrel, similar to those used in powder works. FRITTING. At the present time the materials thus mixed are charged directly into the pot or tank, as the case may be. When the impure alkalies obtained from sea-weed or wood-ashes were used the batch was submitted to a preliminary reamiig process termed "fritting". This consisted in stirring the materials together under the heat of a reverberatory furnace, called a "calcar arch", which effected a partial decomposition and the burning of any carbonaceous matter that might be present, and the "frit" thus obtained was rernelted in the pots. With the use of the purer alkalies made from salt this fritting is not necessary, though heating the batch in the arch may be desirable. CHARGING. The pots having been heated to a white heat, the materials, mixed with a proportion, generally one-third, of ctillet of the same kind as the glass to be made, are shoveled into them. Mechanical chargers have been used to some extent in this country, but not very successfully. As the melted glass is less in bulk than the materials, the entire batch is not charged at one time. The pots are filled as full as possible at first, about two-thirds of the whole batch being charged, and the remainder is shoveled m as the melting and sinking of materials permit. Two or three shovelings or fillings are sufficient. During the melting the grate-bars are kept well supplied with coal, to prevent a rush of cold air into the furnaces, which might split the pots. MELTING. As the melting progresses the teaser (a) watches it most carefully, urging the furnaces to their utmost intensity and determining the fitness or unfitness of tile metal for working, as there are signs which indicate to the practiced eye when the metal is ready, such as the color of the flame or the appearance of proof specimens taken from the pots with a short rod flattened at one end. The escape of the carbonic-acid gas answers the purpose of stirring the materials. When the disengagement of this gas ceases, especially in the manufacture of window-glass, the mass is stirred with a pole of green wood, or a piece of arseuious acid is thrust into the bottom of the pot, thus causing a forcible expulsion of gas and consequent stirring of the materials. When impure materials were used, the close of the period of melting found the surface of the molten glass covered with a thick scum of unvolatilized salts, called "glass-gall", or "sandiver", which was skimmed off. The relative proportions and the purer materials of modern glass houses render this skimming unnecessary; indeed, the appearance of ''sandiver" in any quantity is regarded as an indication of impure materials or wrong proportions. FUSION AND FINING. The melting may be divided into two periods, fusion and fining or refining, the first ending when the materials are thoroughly melted, and the second including the after process of freeing the glass from bubbles, lime, and earthy impurities that do not fuse. For this purpose the glass must be brought to the most fluid state possible, and the heat is therefore raised to the highest point. This process of fining, refining, or "hot-stoking", as it is called in this country and in England, or lieias-ischuren, as it is termed in Germany, involves a very high temperature, which is estimated in certain cases to reach from 10,000 to 12,000 F. (b) Though the authority for this statement is very good, it is doubtless too high, about 3,200 to 3,GOO F. being the average. The time of fusion and refining should be as short as possible, the shorter the better, as long-continued melting or lining detracts from the brilliancy of the glass and favors the formation of threads. The time occupied iu melting varies greatly, depending apon the construction and character of the furnace, the proportion and the character of the materials, and the size of The word appears to be derived from the French " tistur' b Eneyclopa-dia Entaniiica, !>th ed., article. "Glass." 1031 MANUFACTURE OF GLASS. the pots. Gas furnaces will, as a rule, make a "melt" in less time than the old style, and those of the old style that use coal as a fuel will melt in less time than those using wood. The larger the proportion of sand the longer will be the time, while lead will hasten the melting. Very large pots, holding, as some English ones do, 5,000 pounds of material, will consume 48 to 50 hours in melting, while the French pots, of from 1,000 to 1,200 pounds, will melt the batch in 12 hours. This is not uniformly true, however, as the pots in the Bohemian furnaces are stated to hold but 100 pounds, and yet the melting occupies 18 hours. This is due to the construction of the furnaces, the use of wood, and the materials used. TIME REQUIRED TO MELT AND FINE. In England the time of melting in the plate, crown, and sheet window- glass houses is stated to be from 16 to 20 hours, and the time of fining from 4 to 8 hours. In France and Belgium it is somewhat less. In this country the time of melting is about 12 hours, and of fining from 3 to 4 hours. In green-glass houses the time occupied is about one-third less. This glass is inferior to window-glass, and the perfect fusion and fining is not as necessary for the purposes for which it is used as it is for sheet-glass. The time required to make a melt of flint-glass is much longer than that for either of the other kinds ; the pots being covered, the heat is kept out and the melting is retarded. The time is shorter with lead as a flux than with lime, but, as a rule, twice as much time is occupied as in the melting of window-glass. In England the time is from 48 to 60 hours, the batch being very large, the melting consuming about five-sixths of the time; but in France, where pots holding but 1,600 pounds are used, the time of melting is from 8 to 9 hours, and of fining from 1 to 2 more; and, as already stated, the Bohemian houses require 18 hours for a melt of a 160-pound batch. In this country, in lime-glass houses, the melting of a 3,200-pound batch consumes from 20 to 24 hours, the fining from 2 to 4, and the cooling one-half an hour to an hour, the latter process being hastened by opening the mouth of the pot and blowing the blast into it. In France thin pots, with a small amount of batch, have been used to hasten the melting. COLD STOKING. When the fining is completed the molten glass is very fluid, and in this condition could not be worked, as it must by cooling be brought to a viscid or plastic condition necessary for working. To accomplish this the draught is stopped and the grate bars are plastered or the fire is covered with " braize" or fine coke. In some cases the blast is turned into the pots. This is called " cold stoking " or " standing off", or by the Germans "kalt-sch'iiren'\ cold covering. In window-glass works this process requires from one and one-half to three hours; in flint works, from one to two hours. Loss IN MELTING. As already indicated, the process of melting results in the disengagement of the gases that are contained in the materials, as the weight of the glass is considerably less than that of the batch. This loss, however, is chiefly in the gases other than oxygen, though this is expelled to some extent. Mr. Henry Chance (a) states "that very little alkali is lost by volatilization during the intense heat to which it is subjected. I da not find in any case a difference of more than 1 per cent, between the alkali in the mixture and that in the glass produced, and this includes the waste that must necessarily arise in mixing, in carrying the materials to the furnace, and throwing them into the pots". By alkali Mr. Chance evidently means the available alkali in the material charged, and not the entire amount of carbonate or sulphate, as the case may be. Some manufacturers think a larger proportion is lost. I am indebted to Mr. Julius Fahdt for the following very interesting and complete table^ showing the practice of the Austria-Hungarian glass houses : DIMENSIONS OF POTS AND TIME OF MELTING AND WORKING. - EXTERIOR DIMENSIONS. CONTEHTB DURATION 1M HOURS OF Height. Diameter. Weight. Proportion. Heating. Melting. Fining. Cooling. Working. Batch. Cullet. Millimeters. 550 550 450 550 Millimeters. 600 600 450 600 Millimeters. 500 500 400 500 Kilograms. 150 150 75 150 120 108 50 120 30 50 25 30 1 1 i i 8 8 8 10 6 6 6 6 2 1 i 1 Sheet-glass (few exceptions with pots, as in Germany). Flint with lime t 12.00 10.12 10.00 BottlesJ * Small plate of from 50 to 60 square feet. t According to articles. J Bottles are nearly all made in two large establishments with Siemens' tank furnaces. Lead glass is only manufactured in some works for false jewelry in flint and colors, in very small pots, not exceeding 50 to 60 kilograms, which are worked out in lumps, cut and ground. About one-third of the Austrian glass-meltin;; establishments produce raw glass, which is pressed or worked out in heavy pieces for prisms, chandeliers, and heavy ground articles. These are finished by the so-called refiners, who buy the raw glass and finish and sell it. A good many sheet-glass works only make a very thin sheet-glass, which is used in looking-glass- manufacture. The Austrian window-glass, with a very few exceptions, is also very thin, generally not much above one millimeter. This is the reason why th* flmall pots require a much longer time to molt and work out. Austrian factories in general blow their articles much lighter than in Germany. They require a longer time for melting, because their metal is very hard. FAULTS IN THE METAL. The faults in glass that occur in connection with its melting are chiefly those from air or gas bubbles, imperfect fusion, and foreign substances. When the fining has been obstructed by too great 1082 a On the Manufacture of Glass, a lecture delivered before the Chemical Society, March 19, 1868, page 8. MANUFACTURE OF GLASS. 45 difficulty of fusion, the mass becomes thick or viscid and the bubbles are retained, giving rise to what are known as u seed ", " blibe," or " blister ". "When the fusion is imperfect, and the glass is not uniform throughout, the density of various parts of the glass varies and refraction of light is not equal, and consequently images of objects seen through the glass are distorted or out of place. These faults are termed " striae ", and when they show on the surface they are termed "waves". "Threads" or "strings" are produced by cold glass dropping into the metal and not undergoing fusion. " Tears " are vitrified portions of the side or roofs of the furnace that drop into the pot. Mr. Henry Chance's resumt of the defects of crown glass and their cause is so indicative of the many difficulties in the way of producing perfect glass that I copy it : (a) Perhaps the glass has been badly melted and is seedy, that is, full of little vesicles, to which the rotary motion has given a circular shape ; or the gatherer may have inclosed air within his " metal", and a gatherer's blister is the result or a pipe blister, or pipe scales, or dust from the pipe-nose, or dust from the marver, or dust from the bottoming-hole, or dupt from the nose-hole, or dust from the flashing furnace, or bad bullions, or scratches, or mnsic lines, may disfigure the table, or the glass may be crizzled, or curved, or bent, or hard, or smoky, or small and light, defects to explain which -would be a long and dreary task. CHAPTER VII. GLASS-WORKING. METHODS OF GLASS-WORKING. It is not the intention of this report to enter into the minute details of the various methods of glass-working, as it is not intended that this work shall be a perfect hand-book for beginners or for skilled glass-makers. I have only endeavored, while giving full and correct statistics of the trade in the United States, to glance at the history of glass-making at home and abroad, and to give some general idea of the processes employed and of the materials which enter into the composition of glass. For these reasons I shall here only describe in a general way the most important processes used in the manipulation of the melted glass. The chief methods of working glass are three: (1), casting ; (2), pressing ; (3), blowing. Casting and pressing are closely related processes, and blowing and pressing are often combined to produce certain forms of glass, but the processes are generally so distinct as to justify the classification adopted. Glass is also manipulated in many ways that do not properly fall under either of these classes, but they are of minor importance, and either are subsidiary to one or more of these three methods, or are, strictly speaking, reworking glass. PLATE-GLASS. The most important form of cast glass, and the one most largely produced, is plate-glass, or, as it might more properly be called, cast plate-glass. This is the well-known cast, ground, and polished plate used for windows, mirrors, etc., and should not be confounded with the blown plate and Chance's patent plate, which are blown glass. In the manufacture of cast plate furnaces and pots of the ordinary construction are used, the melting-pots, however, sometimes holding as much as 2 or 2J tons of batch. In French works, and in some others, two forms of pots are used, which are placed side by side in the furnace : the ordinary melting-pot, and an auxiliary pot, called a "cuvette", large enough to hold sufficient glass to cast a sheet of a given size. The molten glass is ladled from the pot into the cuvette, allowed to clear, if necessary, and is then cast. In most works, however, the practice now is to pour or cast directly from the pot in which the glass is melted, and in other cases it is ladled from the pots to the casting table. CASTING AND ANNEALING. The casting table, formerly made of bronze, is now made of one piece of cast- iron, (b) heavy and thick, and in width and length exceeding the dimensions of the largest sheet of glass. It is commonly mounted on wheels, running on a track laid down the center of the casting hall or room, on each side of which are the annealing ovens. A heavy cast-iron roller the full breadth of the table is arranged to roll its whole length by means of a spur-wheel on the roller working in gearing on the side of the table. The height from the table at which it rolls, and consequently the thickness of the glass, is regulated by narrow strips of metal placed along the edge of the table, while the width is determined by what is known as the " gun ", two plates of cast metal bolted together, adjustable to the breadth desired and moving with the roller and before it. All being ready for casting, a pot filled with the molten glass is removed from the melting furnace, placed on a truck, and run to the casting table. The pot is lifted from the truck by a crane, is suspended over one end of the table and tilted, and the viscid, semi-fluid mass being poured out, the roller is moved forward, flattening the glass and rolling it to a uniform thickness, while the "gun" prevents it from spreading to a greater width than is desired. As soon as the plate has solidified sufficiently to bear moving, it is laid in the annealing oven on the " flat " to slowly cool. All the operations are performed with the greatest rapidity, that the plate may be as hot as possible when laid in the oven. The number of plates that can be put in an oven varies with the size of the plates. But one layer of those a Mr. Henry Chance On the Manufacture of Croicn and Sheet Glass. b In some cases, in order to overcome the " bowing " of the plate, it is made in a number of pieces. 46 MANUFACTURE OF GLASS. designed for polishing can be placed in it ; consequently a large number of ovens is needed where large plates are made. These ovens are large, shallow, brick reverberatory furnaces, with floors as smooth and as level as possible, as the semi-plastic mass molds itself into the unevenness, and any bending of the plates would make them valueless. As soon as the plate is placed in the oven, all the openings are carefully closed and the oven is allowed to cool gradually to a point where the glass may be safely removed, generally requiring from three to five days. KOUGH PLATE. The cast plate as it comes from the oven is rough and irregular on its surface, constituting the rough plate of commerce, and in this form it is used for roofs and floors, and even for windows where light without transparency is desired. GRINDING, SMOOTHING, AND POLISHING. The plates having been examined for defects, such as spots, air- bubbles, etc., and, if necessary, cut into such sizes as these defects require, the selected pieces are then polished, which operation consists of three processes : (1), grinding ; (2), smoothing ; (3), polishing ; but it is exceedingly difficult to describe these operations without the aid of drawings. Various machines have been invented for these purposes. The machine originally used for grinding was known as the "fly-frame" machine, the design of which is attributed to James Watt, and in one form of this machine commonly two or more plates, according to their size, are imbedded in plaster of paris, spread upon a table. Other plates are imbedded in the under side of two runner-frames or swing-tables, which by a strong fixed bar are caused to move with a transverse motion backward and forward, a circular motion being at the same time imparted by means of a vertical crank-shift, pivoted to the central and upper part of the table and actuated by bevel gearing. Four other cranks, one at each corner of the frame, serve to guide and limit its motion, causing its central point to describe a circle about 4 feet in diameter, so that different portions of the faces of the upper and lower glass plates are continually applied to each other. Sharp river sand, sifted into two different sizes, is used as an abradant. When the surface of the lower plate has been ground quite flat by the coarser sand it is removed, and after careful washing finer sand is substituted. To this succeeds emery powder, a coarser and then a finer quality being applied, the glass being thoroughly washed previous to each change of material, so that none of the coarser particles previously used may remain to cause scratches on its surface. The plates are then turned over, and the same process is repeated on the other side. The smoothing process is carried on with similar machines, the only difference being that emery powder of increasing degrees of fineness is employed. The polishing is done with reciprocating rubbers covered with fine felt and supplied with rouge. The table on which the glass lies also is given a backward-and-forward transverse movement, so that all parts of the plate are brought under the polishing operation. About 40 per cent, of the weight is removed in these three operations. Ordinary plate-glass varies in thickness from one-fourth to three-eighths of an inch. The largest plate ever made was exhibited by the Saint-Gobain Company at the Paris exposition of 1878, and measured 21 feet 2 inches by 13 feet 6 inches. ROLLED PLATE. A form of unpolished plate-glass, known as rolled plate, has been manufactured largely in England for some time, and has latterly begun to be manufactured in France and Belgium. This is used for coverings for hot-houses, for door-panels, for windows, for partitions, and for other places where obscure light is required. The glass is not poured from the pots, but is dipped from them with a large ladle or dipper and poured upon the casting table, which, instead of being smooth aud plain, is engraved or indented in fine lines or flutes or in small squares, lozenges, or even ornamental patterns, the glass, of course, taking on its lower surface the impression of the pattern or lines engraved on the table. The roller is passed over the molten glass as in the ordinary cast plate. These plates are usually cast one-eighth of an inch thick, aud in annealing a large number are piled on their edges in the annealing oven, instead of a few laid flatwise, as is done with plate-glass which is to be polished. By this ladling process numerous "air-bells" and imperfections are inclosed in the glass, but as it is obscured by its roughness they do not affect its usefulness. OPTICAL GLASS. The flint-glass used in the manufacture of opti-cal instruments is also in a certain sense a cast glass, or at least a massive glass, not manipulated by blowing or pressing. For this purpose a glass of the utmost purity, transparency, freedom from color, strise, and imperfections is of the highest importance. As has been already stated, this glass has a large proportion of lead. It is melted in the furnace in a single pot, and Guinand's secret, by which it was first made successfully, consisted in constantly stirring the mass while in a molten condition to prevent the heavier lead silicate from falling to the bottom. After the glass is thoroughly melted the stirring is continued until the contents are cooled down to little more than a red heat, when the furnace is closed and the metal is allowed to cool and anneal gradually in the pot within. When withdrawn, the pot is broken and the mass of glass removed. Optical glass is also blown into thick cylinders, and sometimes is cast in slabs from one-fourth to one inch in thickness. The crown optical glass is made with as great care as the flint, but it contains no lead, and has about the same composition as window-glass. STKASS. This is the glass used in the manufacture of the remarkably faithful imitation of precious stones, which have been and are still so common, and is manufactured somewhat in the same way as optical glass, special precaution being adopted in the melting of the materials. Formerly it was believed that only rock crystal could be used in its manufacture. This belief, however, is wholly without foundation, sand which is pure making equally good Strass. 1084 MANUFACTURE OF GLASS. 47 PRESSED GLASS is, strictly speaking, one form of cast glass, the molten metal being gathered and cast in a mold which would correspond with the table of the plate-glass works, the plunger of the press answering to the roller. There are, however, so many and important variations in the methods of pressing as to justify its classification as a separate process. Pressing by mechanical means in metal molds, which is an American invention, is a most important and valuable improvement in glass-making, and by its adoption comparatively unskilled labor can be substituted for the highly trained workmen demanded by the blowing process, and cheaper materials can be used. Labor as highly skilled as that required in glass-blowing is not necessary, as intelligent men can be trained in a short time to perform the work, and a glass rivaling lead flint in whiteness and clearness, but not in brilliancy, can be made with lime. In the pressing process as usually practiced a metallic plunger is driven into a metallic mold, into which molten glass has leen placed by mechanical means, the glass taking the form of the mold upon its outer surface, while the inner is modeled by the plunger itself. The simplest form of mold is a flat slab of iron or other metal with slightly raised sides. For articles of some complexity molds are made in two or more divisions, hinged together (joint molds), and opening outward. The chief parts of the mold are termed the -'collar" and the "base". The ordinary form of press used is shown in the accompanying cut, the mold, with its handles, being shown on the table of the press. The molten glass having been gathered and dropped into the mold, a sufficient quantity is cut off, the mold is pushed under the plunger, and the long lever at the right of the press is pulled down. The plunger enters the mold, the glass is pressed into all parts of the same, the plastic mass solidities, the plunger is withdrawn, the mold opened, and the glass in the required form is withdrawn, to be fire-polished and annealed. If too much glass is cut off, the article is too thick ; if too little, it fails to fill the mold, and the article is spoiled. Though this is quite a simple operation, and though as great skill as in the old method of glass-blowing is not required, considerable practice is still necessary to gather the right amount of metal and to cut it off so as not to waste glass, and also to keep the mold at the right temperature. If it is too hot, the glass will adhere to the die and plunger; if too cold, the surface will not be clear and transparent. IMPROVEMENTS IN THE PRESSING PROCESS, (a) Since pressing was first introduced many improvements have been made; indeed, the improvements in glass-making during the past ten years in connection with the manufacture of pressed glass have been most marked, one very important one having been what is known as fire- polishing. By this process the outer film of glass is roughened by contact with the mold, and the film is repolished by a slight reheating. Some of the recently invented mechanical devices for this reheating are most ingenious, and have made the production of certain articles possible which it was believed could not be produced by pressing. One of the chief difficulties in pressing glass is the production of sharp angles, which are so easily obtained in cut glass. If these are secured in pressing, they are apt to lose their sharpness in fire-polishing and reheating. Thi.s defect has been obviated in some degree by making the angles longer in the molds, so that when they are softened by the heat they still stand enough in relief to give marked and distinct outlines. To obviate the uneven surface of flat or fluted articles the molds have been constructed so as to make the flutes deepei in the middle, and with angles slanting toward this point. It will readily be seen that a flute composed of two angles tending to the center is not as likely to show defects as if it was of a flat surface. Another important improvement in connection with pressing glass is the process of cooling the molds by the use of air, an invention which has doubled their durability. M OLD-MARKS. A common defect of pressed ware is the marks left on the glass at points where the different pieces of the mold are joined together. However skillfully the molds may be made, in course of time the joints will work loose through the expansion and contraction of the metal, and the glass will gradually be pressed in the loose spaces of the joints, thereby imprinting on the surface of the articles ribs or sharp threads, marring the beauty of the work. To obviate this molds are made to open at such places and parts of the design that the marks left can scarcely be seen ; for instance, in goblets the marks are left on the edges of angles. The parts of the molds are also combined so as to leave the marks on the edge of the scallop made by the top of flutes in a goblet or tumbler. Tumblers, however, are rarely made in "joint molds'', but in solid ones. MOLDING ARTICLES WITH LATERAL DESIGNS. Various mechanical devices have been adopted that have permitted of the production of forms that at first seemed beyond the skill or ability of the glass-presser. Pieces requiring to have designs pressed in the side, which would prevent them from coming out of a mold made in one piece, have been made by having sliding lateral pieces. These pieces are moved forward and withdrawn by suitable means, leaving them free to come out of the mold. Improvements in the same order have also been made for molding handles, forming hole's in handles by means of sliding pieces, which are pushed through the side of the mold and withdrawn to take the pieces out. When articles are so shaped oil the outside as to present a few protuberances, and it is not thought advisable to open the mold, in order to avoid mold-marks the a Many of the following facts about pressing are condensed from Charles Co!n's report on glass and glassware. 1085 48 MANUFACTURE OF GLASS. melds are so combined that the protuberances are made by sliding lateral pieces, which, when withdrawn, allow the object to be taken out. Letters, monograms, and ornaments have been made by introducing lateral pieces in molds containing the proper designs. These pieces are changeable, and the same shaped article may be made having different lettering, etc. MOLDING CURVED HOLLOW ARTICLES, LAMPS, GOBLETS, AND TAPER ARTICLES. Curved tubes and glass slippers are made by giving the plunger a descending curvilinear instead of a vertical motion, and lamps, goblets, and similar articles are frequently made by first pressing the foot, then blowing the head or body upon it, placing the foot in suitable bearings to connect the two together. The upper part may be either blown in a mold or previously shaped with tools and made to adhere while the glass is hot. Bowls are also made by first pressing, then inverting them, and then pressing the foot and stem upon them. Pieces which are wider at the top than at the bottom, as a decanter, cannot be pressed in the usual way, since the plunger is always a cone, which must be pushed into the mold and withdrawn. These pieces are pressed bottom up, and lips or projections sufficient to form the bottom are formed in the mold. The piece, after being pressed, is withdrawn from the mold, the bottom is heated, and with a tool the lips are brought together to close it up. MOLDING MOUTHS, NECKS, ETC. In shaping tools for the mouths of bottles, jars, etc., there are several combinations to produce effects not to be obtained by hand. The ordinary neck-shaped tool for making bottle necks is made of a central pivoted piece to form the inside of the neck and two stationary pieces to form the outside. Sometimes the necks of certain jars require to have a screw shape molded in the inside, and to accomplish this the central piece of the shaping tool is made screw-like, the two outside rubbing pieces of the desired shape, according to the style of jar. It is sometimes desired to form cavities or projections in or on the necks of jars, and this is usually done by having laterally-moving pieces attached to the inside former or the outside jaws, as the case may be. These sliding pieces are operated when the tool is at rest after shaping the neck. In the same order of tools may be classed the formers for making pouring-lips on the necks of cruets. These tools have suitably shaped jaws, which are pressed against the neck to give it the proper slant. It is also desirable sometimes to make holes in the side of a jar or jar-cover. This is done by having metallic pegs placed on the outside jaws, which are pushed iu through the metal to pierce it. The middle piece fitting the inside of the bottle-neck in some of the forming tools is so made that at the time of entering it is very narrow, but is gradually widened by forcing apart the two sections of which it is made. Molasses-cans are now made with a glass pouring-lip at top and slanting channel to run the dripped molasses into the can again, the whole being closed by a metallic cover. To form the glass lip the piece is molded upside down, with bottom flaps to close up the can. In this position the can forms a cone, and the plunger can therefore be pushed in and withdrawn with facility. The bottom of the mold is made of a suitable shape, and the plunger is so combined with the bottom piece that the opening in the mouth of the can is made at the same time as the body is pressed, the film of metal at the mouth being so thiu as to be readily removed by a sharp blow. By this device clock frames, decanters, pipes open at both ends, etc., can be made. HANDLES. Handles can be pressed in one mold, and the body of the object subsequently blown upon them in another mold, the operation cementing the parts together while the metal is hot. Small hand-lamps have been blown in ordinary iron molds, and the handle for each formed by allowing hot plastic glass to descend in a channel at the side until the two ends meet the bowl of the lamp and become cemented to it while hot. LAMP BODIES WITH FEET AND SCREW COUPLING. Lamps are sometimes made with the foot and bowl fastened together by means of a metallic casing screwed over the two parts. In order to obtain the screw-pegs at the bottom of the lamp bowl and the top of the foot molds have been devised so as to give to the bottom piece a rotary motion, to withdraw it from the formed peg. This style of forming screws is to avoid the mold-marks which are made when the mold opens. LAMPS WITH METALLIC PEGS OR COLLARS. Lamps are blown with metallic pegs or collars imbedded in the glass. The pegs are previously heated, set in recesses in the molds, and the lamp blown over it. INSULATORS. In telegraph insulators, however, requiring a hollow screw, a rotating retreating bottom piece becomes a necessity, as the plunger cannot be pushed and withdrawn, owing to the projecting screw-threads. BALLS. Round glass balls, used for castors or for shooting at, are now made by using molds containing several sections, which leave only a small connection of glass between the balls. A rod of hot glass is prepared, then rolled lengthwise 'over the different sections of the mold, and is gradually shaped into several balls, slightly attached together by thiu connections. These balls are easily severed, and are then perfectly round. MOVABLE-BOTTOM MOLDS. Molds have been made with movable bottoms, to allow the surplus glass, when in excess, to force the latter down, thereby increasing the thickness of the bottom piece. In order to equalize the distribution of heat in iron molds, they have been so made that by varying the thickness of the different parts the cooling and heating become equalized. BATTERY JARS. To manufacture battery jars having tubular formations running from top to bottom a ring- plate is used having two mandrels attached to it and falling into suitable recesses in the bottom of the mold. This ring-plate being adjusted in the mold, the plunger is made to come down, and by its pressure the hot glass is made to run round the mandrels while the jar itself is being formed. The plunger having been withdrawn, the mandrel plate is pulled out, and the tubular cavities now appear properly formed. 108(i MANUFACTURE OF GLASS. 49 MOLDS FOR FLAKING ARTICLES. Articles wider at the bottom than at the top on the outside maybe pressed by introducing between the outer shell of the mold and the plunger a cylinder tapering wider from top to bottom ; but the inside of the article must, of course, be made tapering downward toward the center, so that the plunger may be withdrawn. It will be understood that the plunger having been withdrawn, the article being wider at the bottom than at the top, it cannot yet be taken out of the mold. To do this the intermediate cylinder is withdrawn, and the article is now left free to come out. MOLDING ARTICLES WITH BULGING BODIES. A combination mold has been made to press molasses-cans and such articles which are wider in the middle than at both ends, and it is plain to be seen that to make such cans no plunger can be used to press the article all the way down, on account of the belly of the can. To obviate this inconvenience molds have been made of several pieces, as follows : The upper part, consisting of the neck and handle, is pressed in a mold having a movable bottom piece, which is run up past the belly of the can, but only to a proper distance, so that the bottom may be left thick enough to furnish sufficient material to form the body. The plunger is provided with air-passages, to admit of the bodies being blown, and the lower part of the mold, through whi'.-h the bottom piece ascends, is made of the proper shape to form the body and the bottom. The operation is as follows : The mold bottom piece is run up to its proper height, glass is introduced in the mold, the plunger is brought down, thereby forming the neck and the handle of the can and a thick glass bottom. The mold bottom piece is now lowered, and the thick glass bottom is dilated and made to fit the lower mold by the pressure of the air sent through the plunger, thereby finishing the piece. MOLDING ARTICLES WITH OPENINGS. It is sometimes desirable to make certain articles with openings, such a.s on the top of a lamp head to leave an opeuing for filling the lamp. These holes or openings are produced as follows : After the lamp head has been properly shaped, a small quantity of hot glass is dropped upon the lamp top. which has been previously reheated. The hot glass and top of the lamp being now sufficiently plastic, a tool somewhat in the style of those for forming bottle neck* is used. This tool consists of an annular piece, which is brought over the hot lump of glass and shapes the outside. While this annular piece is in contact a central pin is [lushed forward and pierces the glass, thus producing the opening. Should it be required to cement a cap over tliu opening, the shaping tool is provided with two levers, having ends properly shaped for the purpose. These ends are pressed on the outside of the tube and form recesses. SPRING SNAPS FOR FIRE POLISHING. Many articles, after being molded, pressed, or blown, require to be held by the foot for fire-polishing or for giving them a final shape. It has been customary, heretofore, to fix the foot to a piece of hot glass on the end of au iron rod, and then to put on the finishing. To detach the pieces it is necessary to part the two by giving a sharp blow on the iron rod. The foot frequently retains pieces of broken glass, which must be removed by grinding, and to avoid this spring ' snaps" are used. These consist of a couple of jaws mounted on springs, so that they can open and shut. These jaws are fastened at the end of an iron rod like a blow-pipe. If a goblet is to be finished the process is as follows: The jaws are made to open, and, by the action of the springs, they immediately close upon the foot and hold the goblet ready to be finished. Sometimes these jaws are so su-ranged that they can be set forward and back and fastened by screws. COOLING HEATED MOLDS BY AIR BLAST. When pressing glass continuously for a long time the molds often lecome too highly heated, and in this state glass is very apt to stick to them; but this inconvenience is now done si way with by a system of blowing air into the molds. By means of a revolving fan or other device and tin pipes arranged around the furnace a continuous stream of air is furnished. India rubber pipes are attached to the tin pipes at suitable places, and by this means, after each pressing, or as often as necessary, a stream of air is sent inside of the mold, thereby cooling it The air circulating in the pipes may also be used for the ventilation and cooling of the glass house. APPLICATION OF STEAM TO GLASS-PRESSING. Attempts have been made of late to use presses for pressing glass by steam or compressed air. One of these presses has a set of molds carried on a revolving bed, and is operated by a presser like a hand-pres.s. The power, however, is applied to the presser by means of an auxiliary steam-engine, which is continually at work. Whenever au article is to be pressed, by suitable leverage the presser is forced down, then released, the bed-plate revolves far enough to bring another mold under the presser, and the operation is repeated as often as desired. Mechanism is attached and operated also by steam, so as to push the pieces out of the mold after they are pressed. These are the principal features of the invention. APPLICATION OF CO^IPRESSED AIR. In the other press steam is replaced by compressed air contained in a reservoir, which may be filled by means of an air compressing engine. The bed-plate carrying the molds has a rectilinear motion. When an article is to be pressed, the mold is brought under the presser, and by means of suitable valves and pipes air is sent to a cylinder piston carrying- the plunger, the pressure of the air forcing the presser down into the mold and reversing the valves, and the piston and presser flying back. A new mold is now under the plunger. This operation may be repeated as often as desired by simply opening and closing the air-valves. In this press, as in the other, the pieces are forced out of the molds by rising plugs or bottoms. The different motions are entirely automatic, with the exception of operating the air- valves. Though steam and air have been used, the success reached has not been great. 50 MANUFACTURE OF GLASS. INCLOSED AIR-BUBBLES. In order to form the bubbles which are often seen inside of solid pieces of glass these have been pressed with cavities on the outside, and, after being reheated, the cavities are closed by pressing the outside down with suitable tools, thus inclosing the air. BLOWING is used in the production of cylinder or sheet glass, of table and similar ware, with or without the use of molds and of bottles. WINDOW-GLASS. In the production of window-glass a square or an oblong furnace is used. Badiating from the work-holes, and so arranged as to be on the edge of a pit some 7 to 10 feet deep, are long stages, separated by spaces sufficiently wide to allow the workman to swing about his long tube to form his elongated cylinder. When the glass is ready for blowing the workmen take their stations, each having his own pot and stage, and also assistants, and commence gathering the glass, which is done by dipping the end or nose of the pipe or hollow rod of iron into the pot of molten glass, twirling it around to equalize the thickness of the gathering, and collecting a lump of glass at the end. After gathering the amount of metal required, generally about 20 pounds, the workman rolls the gathered glass on a block of wood so hollowed out as to allow the lump when placed upon it to be extended by the blower to the diameter ultimately required. Here it is shaped into a solid cylindrical mass, water in the mean time being applied to the block to keep it from burning and to give brilliancy to the surface of the glass. When the mass of metal is sufficiently formed and cooled, it now being of a pear shape, the blower raises the pipe to his mouth at an angle of about 75, blowing into the glass and turning it in the wood block until the requisite diameter is reached. It now has the appearance of a hollow flattened globe. This mass is then reheated, and when it is sufficiently softened the workman begins swinging it over his head, reheating and swinging in the pit until it has reached the desired length, which is about 45 inches. This is the most difficult part of the operation, uniformity of substance and diameter being chiefly the result of the skill of the workman, who, when he finds the metal running out too freely, holds the cylinder vertically above his head, still keeping it filled with air, and then by dropping elongates and thins it. The cylinder is now, say, 45 inches long by 12 inches in diameter, one end being closed and the other having the pipe attached to it. The thinner cylinders are opened by the workman blowing into the pipe and then stopping it with his finger, and at the same time applying the lower end to the fire, when the air inside is expanded and the point of the cylinder bursts open, this being the. hottest and most yielding part. The aperture thus made is widened out to the diameter of the cylinder by subsequently turning the cylinder to and fro with the opening downward. The thicker cylinders are sometimes opened by attaching a lump of hot glass to the end, which thus becomes the hottest and weakest part. The blower forces it open, as in the case of thin glass. The opening is enlarged by cutting it round with scissors.- This method is used in preference to opening it in the furnaces, as it occasions less waste. The other end, which is attached to the pipe, is now cut off by the workman, who, having gathered a small quantity of metal on his poutil, draws it out into a thread and wraps it around the pipe end of the cylinder, letting it remain for an instant, withdrawing it suddenly, and immediately applying a cold iron to the heated part, when it cracks where the hot string of glass had been placed. The weight of the cylinder, as finished, is about two-thirds that of the lump of glass which the gatherer collected. The finished cylinder is now split open either by a red-hot iron or by diamond, which, attached to a long handle and guided by a wooden rule, is drawn along the inside of the cylinder, the edge of the glass being rubbed with a cold iron, as in the case of disengaging the pipe. FLATTENING. The cylinder is now ready for the flattening oven, which is generally a circular oven with a revolving bottom, composed of a number of stones'as smooth as possible. The cylinder is laid in the oven with the split side uppermost, and is soon opened by the flame passing over it, and falls back in a wavy sheet. The flattener now applies another instrument, called the polissoir, which is a rod of iron furnished at the end with a block of wood, and rubs down the waviness into a flat surface, often using considerable force. The flattening-stoue is now moved to the coolest portion of the furnace, the sheet is delivered by means of the flattening fork to the cooling-stoue, and from this, when sufficiently rigid, it is lifted and is piled on its edge and annealed in an annealing kiln or laid flatwise on iron carriages, which are conveyed through a long annealing chamber, called a leer. When annealed they are examined, cut into a size that the defect will permit, and packed. DEFECTS OF WINDOW-GLASS. Mr. Chance thus describes the many vicissitudes through which window-glass passes in the processes of manufacture: The manner in which a sheet spared by ene process is disfigured by another is sometimes curiously provoking. Standing before the table of the " assorter", your eye lights upon a piece -which, blown under an evil star, has imbibed in the glass house every possible defect. The founder, skimmer, gatherer, and blower have all stamped their brand upon it. It is seedy the vesicles, which were in the crown tables rounded by the rotary motion of the piece, here elongated by the extension of the cylinder ; it is stony, disfigured with stony droppings fromthe furnace; stringy, thin threads of glass meandering over its surface; "ambitty," covered with stony speckles, symptoms of incipient devitrification; conspicuous with gatherers' blisters and blisters from the pipe; badly gathered; badly blown thin here, thick there, and grooved with a row of scratches ; and on this abortion the flattener chances to have exerted his most exquisite skill ; it has passed through his hands unscathed, flat as a polished mirror, yet, from its previous defects, entirely worthless. Next comes before you a piece whose beginning was miraculous no seeds, no blisters ; it prospered under the hands of the gatherer and blower, and left the glass house a perfect cylinder. But the croppie of the flattener marked it ; the fire scalded it ; dust fell upon the lagre and dirtied it ; scraps from the edges of the preceding cylinder staid upon the lagre and stuck to it ; the stone scratched it ; and the heat of the annealing chamber bent it. Such are the difficulties to which every cylinder is subject those of the glass house and those of the flattening kiln. Not all, however, are such as these ; there are good as well as bad. but the good arc generally in the minority. MANUFACTURE OF GLASS. 51 SIZE OF WINDOW-GLASS. When the manufacture of glass was new in England the size usually blown was 36 by 20 inches. This is now somewhat increased, and cylinders 85 by 49 inches have been blown, and in some cases blown cylinders 158 inches long by 26 inches in circumference and 70 inches long by 60 inches in circumference have been made, but such large sizes, and indeed any over 60 by 40 inches, are exceedingly difficult to make. The thickness is computed by the number of ounces to the square foot. The average size of 15- and 21-ounce glass is 48 inches by 34 or 36 inches. BLOWN AND PATENT PLATE. In various parts of England thick blown glass is often ground and polished in a manner somewhat similar to the cast plate of commerce, and is known as blown and patent plate. The cheap production of this glass was made possible by the remarkable invention of Mr. James Chance, who conceived the ingenious idea of laying every sheet of glass intended to be ground and polished upon a flat surface covered with damp pieces of soft leather. Two sheets thus placed are turned one against the other in a horizontal position, sand and water being constantly supplied between them by means of a most ingenious machine. The two surfaces are rapidly rubbed one against the other in all directions and ground and afterward polished. BLOWING FLINT WARE. All glass when in the plastic condition can be blown with greater or less facility. This statement applies not only to the lead flint of England, but to the lime and half crystal of other countries. In blowing and working the various glasses of these countries into the many forms of blown wares the process is essentially the same. The metal is gathered in a manner similar to that described under window-glass. The metal, so gathered, is rolled on the marver (a corruption of the French word mar&re, marble being formerly employed), which is a slab of cast-iron with a polished surface. Upon this slab the lump of glass is rolled to give it a regular exterior, so that the blowing may give a uniform thickness of the metal. This lump of glass is then expanded by blowing and lengthened by swinging. A pontil, puutee, or polity, a solid iron rod, tapering and varying greatly in length and strength, is attached to the blown globe of glass, when the blowing rod is removed by wetting the glass near where the tube enters. The workman now takes the pontil from bis assistant and lays it on the chair, which is a flat seat of timber about 10 inches wide, each end being fixed to a frame connected with four legs and two arms, the latter being inclined. This pontil is rolled backward and forward by the workman with his left hand, thus forming a throwiug-wheel of great delicacy, while with his right he molds the glass into the various shapes required by means of a very few simple tools. By one of these, called pucellas, the blades of which are attached by an elastic bow, like a pair of sugar-tongs, the dimensions of the vessel can be enlarged or contracted at pleasure. Any surplus matter is cut away by a pair of scissors. For smoothing the sides of the vessel a piece of wood is used, and for flattening the bottom of tumblers or similar purposes the battledore, a flat square of polished iron with a wooden handle, is used. In these operations the article operated upon may be reheated several times. After it is finished it is detached from the poutil by a sharp blow and carried on a pronged stick to the annealing oven or leer, which is a low arched furnace, generally of considerable length. In this oven small tracks are laid, on which wagons mounted on four wheels are placed, the articles to be annealed being filled into such wagons. These are slowly pushed through the ovens, and are removed at the opposite end. FLINT-GLASS CUTTING, ENGRAVING, AND ETCHING. The sparkle and brilb'ancy of flint-glass are developed by the process of grinding and polishing, technically called glass-cutting. Motion is communicated to the glass- cutter's mill, which is of wrought- or cast-iron, by a pulley and band. Over it is suspended a wooden trough or cistern, containing a mixture of sand and water, which, for the operation of grinding, is fed on the wheel as required. Smoothing is done on a wheel of fine sandstone, to which water alone is applied, and for polishing a wooden wheel, supplied with emery, and finally with putty powder (oxide of tin), is employed. The trough under the wheel receives the detritus of the grinding and other operations. The articles are held in the hand, and are applied to the mill while rotating. The punty marks on tumblers, wine-glasses, and the like are ground oft' by boys holding them on small stone-mills. Ground or obscured glass is made by grinding the surface on a wheel with sand and water. In some works in this country the article is placed on a lathe, and while it is revolving sand and water is applied by a wire brush. Iron tools, fixed on a lathe and moistened with sand and water, are used to rough out the stoppers and necks of bottles, which are completed by hand polishing with emery and water. Engraving is the production of ornamental surfaces by a fine kind of grinding, mostly done with copper disks revolving in a lathe. Etching is variously done by submitting the portions to be etched or bitten to the influence of hydrofluoric acid, the remainder of the glass being stopped off or protected by a coating of wax or some pitchy compound, (a) BLOWING IN MOLDS. In blowing bottles or other articles the same method is pursued in gathering the glass as is described above. When sufficient glass has been gathered by the assistant, it is handed to the blower, who rolls it upon a marver, blowing into the metal and forming the rough outline of the article. This is then put into a press or cast iron mold, which is divided into two or more pieces, and which the workman operates by his foot, opening or shutting at pleasure. As the glass is dropped into this mold, and the mold is shut, the workman blows into the glass to cause it to fill all parts. The glass immediately solidifies, the blowing-iron is broken off, and the article carried to the annealing furnace, the mouth, if it is a bottle, having previously been fashioned. a See Encyclopaedia Britannica. 09 M M 1083 52 MANUFACTURE OF GLASS. The great objection to molds is the injurious effect on the surface of the glass. This objection has been overcome by tne use of wooden or carbon molds fitted in metal frames, the use of which is quite common in France and Belgium. FASHIONING ART-GLASS. To describe the various methods employed for manipulating art-glass, and to enter further into details regardiug methods of fashioning the higher grades of glass for table use, hardly fall within the scope of this report. Those interested in these matters, however, are referred to various works on this subject, especially that of Mr. Apsley Pellatt on the Curiosities of Glaus HaJcing, Mr. Alexander Nesbitt's Hand-book on Glass, and the recent publication, Glass in the Old World, by M. A. Wallace-Duulop. THE PORTLAND VASE. Though I have not deemed it advisable to enter into any extended description of the different processes employed in the manufacture of what I have termed art-glass, this account would be incomplete without some reference to the Portland vase. This vase was found in a marble sarcophagus of a sepulchral chamber under the Monte del Grano, about 3 miles from Rome, on the road to Laureutium. The inscriptions on the sarcophagus showed it to have been dedicated to the memory of the Emperor Alexander Severus, killed A. D. 325, and his mother, Julia Mammoea. The vase measures 10 inches in height by 7 in width, and is ornamented with white opaque figures in bas-relief upon a dark-blue transparent ground. This blue ground was originally covered with white enamel, out of which the figures have been sculptured in the style of a cameo with astonishing skill and labor. For a long time this vase was supposed to be of stone, but now there is no doubt that it is of glass, and is supposed to date about two centuries before Christ. Immediately after its discovery this vase was placed in the library of the Barberini family, who sold it to Sii William Hamilton, by whom it was brought to England and disposed of to the Duchess of Portland, from whom it received the name by which it is now known (the Portland vase), having previously been called the Barberini. At the sale of the museum of the Duchess, in 1786, the vase was purchased for 1,029 by her son, who permitted Wedgwood to copy it. Fifty copies were made in jasper ware, which were sold at 50 guineas apiece, but the sum received did not pajfor the reproduction. The vase is now in the British museum, where it is carefully guarded, (a) It was for a long time believed that modern skill was inadequate to the reproduction of this vase, or indeed to the production of work similar in character; but the intelligence and remarkable artistic skill of Mr. John Northwood, of Wordsley, near Stourbridge, England, has not only succeeded in reproducing this vase, but in producing similar vases fully equal, if not superior, to the Portland. The reproduction of the Portland vase by Mr. Northwood was undertaken with the assistance of Mr. Philip Pargeter, who manufactured the vase used, and after a large number of trials succeeded in imitating the full rich blue of the original. He coated the copy a sufficient thickness with a layer of white, soft, opal glass, and succeeded in welding them together with the utmost thoroughness. The vase was now ready for Mr. Northwood to operate upon. His mode of proceeding was to cut away the opal by hand with chisels and gravers and carve upon it the entire design of the original in the same manner as the finest cameo engraving. For the entire ground of the design the opal has been literally chiseled away and the surface of the blue glass polished. The figures, trees, etc., composing the design are left in relief in the opal, and are carved with consummate skill and unapproachable delicacy. Mr. Northwood devoted three entire years to the work. In addition to the skill required on the artistic part of the work the artist met with unexpected difficulties in contending with a flaw in the metal. The character of the work was such, also, that the ordinary glass-engravers' tools would not answer, and new ones had to be invented. The result has been, however, that again it has been shown that modern art, in many respects, is equal to ancient. This copy is valued by Mr. Pargeter at 1,000. Since reproducing the Portland vase, which was finished in 1877, Mr. Jforthwood has produced others of a similar character that are regarded by some critics as even superior to that work. At the Paris exposition of 1878 a vase was shown in the exhibit of Thomas Webb & Sons, representing the triumph of Galatea and Aurora. This vase at the time was unfinished, but its value was estimated at $15,000. Mr. North wood has also produced a vase called the Milton vase, which in beauty of conception and in exquisite and delicate execution is believed to surpass the Portland vase. TEMPERED, HARDENED, OR TOUGHENED GLASS. In 1875 M. Alfred de la Bastie, a French gentleman, announced that as the result of a series of experiments he had discovered a method of so tempering or hardening glass that the strength of the material would be greatly increased. His experiments were based upon the assumption that the fragility of glass is due to the weakness of the cohesion of its molecules, and that if the molecules could be forced closer together, thus rendering the mass more compact, the strength of the material would be increased. In his first experiments he endeavored to produce this result by mechanical compression while tue glass was in a fluid or viscid state. Being unsuccessful in this, he was led to make use of a modification of the method by which the well-known Prince Eupert's drops have so long been produced. In the manufacture of these drops- a piece of very fluid glass is dropped into water, assuming, as it falls, the shape of a tear or drop. The outside of the glass cools at once, the inside remaining partly fluid for some time, but ultimately the mass becomes . _ a After being placed in the British museum it was left uncovered, and was dashed into a thousand pieces by the cane of a madmaa. The pieces, however, have been so skillfully joined as to leave no trace of the accident. 1090 MANUFACTURE OF GLASS. 53 perfectly solid. This indicates that the outside layer is at once condensed by cooling, while the inside remains fluid and is consequently more distended. Though the outside of the drop is very hard, and a severe blow may be struck upon the thick part without any perceptible effect, if the tail or thin end is broken the whole mass instantly flies to pieces with a slight detonation. Dumas explains these phenomena by stating that when at last the central and dilated parts of the drop become cooled they must have retained points of adherence to the surface, and consequently occupy a larger volume than that which agrees with the temperature to which they are reduced. The central molecules, therefore, must be much distended and exert a more powerful contracting influence on the surrounding parts; are, in a word, " on a strain," as a workman would term it. At the instant when a part of the envelope or outer portion is broken the molecules held by it briskly contract, draw in with them all the others, and thus determine a multitude of points of rupture ; and as this effect is instantaneous, the particles move very rapidly and drive out the air before them, producing a sudden dilation and contraction of the latter. BASTIB'S TEMPERED GLASS. In view of these well-known phenomena, M. de la Bastie endeavored to find a method by which the hard surface produced by immersion in water could be retained and thickened while the objectionable tendency to flying in pieces would be lessened or removed. In his experiments he found that two conditions were necessary : first, the glass must be brought to just that degree of heat where softness or malleability begins, the molecules then being capable of closing suddenly together and condensing the material when immersed in a liquid at a considerably lower temperature ; second, the liquid employed must be capable of being heated much higher than water without boiling. He therefore adopted an oleaginous mixture, into which he plunged the glass, reheating the latter, which had previously been annealed in a kiln. DIFFICULTIES OF THE PROCESS. This process was admittedly a success as far as flat or solid glass was concerned, although the necessity of heating the glass to the point of softening rendered it extremely difficult to handle, and the liability of the bath to catch fire had to be lessened in some manner; but both these difficulties were overcome by M. de la Bastie's apparatus for reheating and plunging the glass. The process, however, was found to be defective as regards any other forms of glass, such as hollow flint vessels, as such glass, while being reheated, is almost certain to collapse before reaching the required temperature. In M. de la Bastie's experiments at Whitefriars glass works, England, therefore, a new plan was adopted, by which the bath was placed as Hear the mouth of the working pot as possible, and the workmen dropped the finished vessels directly into it. This process was found to answer well in the manufacture of all vessels made in one piece, and the somewhat complicated apparatus for reheating was doue away with. As regards the character of the glass obtained by the process, Mr. Powell, of the Whitetriars woiks, disposes of some popular fallacies in this wise : Hardened glass is not unbreakable ; it is only harder than ordinary glass, and, though it undoubtedly stands rough usage better, it has the disadvantage of being utterly disintegrated as soon as it receives the slightest fracture, and np to the present, until broken, of bring undistiuguishuble from ordinary glass. This glass is known as "toughened" glass, and we have seeu the terras "malleable" and " annealed " applied to it. Nothing can be more misleading than these unfortunate epithets. The glass is hard, and not tough or malleable, and is the very opposite to annealed glass. Annealed glass is that glass the molecules of which have been allowed to settle themselves; the molecules of hardened glass have been tortured into their position, and until the glass is broken are subject to an extreme tension. It is the sudden change of temperature that "hardens"; glass heated np together with the oil may be annealed, but decidedly is not hardened. A piece of hardened glass is only a modified Rupert's drop, i. e., it is case-hardened; the fracture of both is ideutii-al ; both resist the diamond and both can be annealed. * In our experiments we found that while the glass could be marked with the diamond or smoothed and engraved in the ordinary way, still an endeavor to cut it with the diamond, or even the disturbance caused by the smoothing-whee!, when penetrating to any appreciable depth, tended to weaken or even to cause the destruction of the entire muss. For practical utility the value of glass tempered by M. de la Bastie's process is of course impaired by its inability to be cut, and also its utter destruction by the slightest fracture. It will stand sudden changes of temperature without breaking, but if reheated slowly to a high temperature its temper is destroyed and it becomes as common glass. The great anticipations which were at first formed as to the extended use of the glass have not been realized. M. de la Bastie has made some improvements in his process, and two eminent London firms adopted it and manufactured the glass for a time, but finally gave it up. In this country Messrs. E. dc la Chapelle et C ie ., of Brooklyn, manufacture on the Bastie system, but the process is not a complete success, the glass not being uniform in temper or producing the best results. SIEMENS' TEMPERED GLASS. While M. de la Bastie was introducing his discovery to public notice in Europe Mr. Fredench Siemens, who is owner of the most considerable glass-bottle works in Germany and Bohemia, and perhaps in the world, was studying the question of tempering glass 03- following a different course from that selected by the former. Instead of plunging hot glass objects into liquids, Mr. Siemens, fearing distortion of the articles to be treated, concei%'ed the idea of subjecting them to tempering by placing them in molds between cooled surfaces, whereby not only would their shape be maintained intact, but force could also be applied, if necessary, to press the molecules of glass firmly together. By these means glass of any shape could be tempered, and the process was considered to be particularly well suited for the production of strong window-glass, which had not previously been attempted. Mr. Siemens, however, soon found that the glass so prepared was liable to the defect of breaking suddenly, and he had to undertake further researches, with a view of perfecting his process, by the removal 1091 54 MANUFACTURE OF GLASS. of that defect. When a cube of tempered glass is considered, it will at once be seen that, all its surfaces having been subjected to the same cooling influence, the edges, and particularly the corners, will be much more cooled than the broad surfaces. At each edge the cooling will take place from two surfaces, and at each corner from three surfaces, from which circumstance Mr. Siemens inferred that glass so treated could not be homogeneous in character, and that sudden breakages were due to that cause. To overcome this defect Mr. Siemens modified his process so as to limit the cooling influence of his apparatus to two surfaces of the glass under treatment. From these surfaces the cooling and tempering action is transmitted to the center of the mass in a uniform manner, whereby homogeneous glass is produced which is found to give entire satisfaction. By Mr. Siemens' process glass may be tempered to various degrees of hardness, according to the use for which it is intended. For the production of window and other flat or molded glass presses, cooled by the circulation of water, are employed, but in dealing with large castings of glass, such as railway sleepers, for example, the castings are packed in rectangular boxes, or trucks, heated internally for their reception, and all interstices between them are filled up with a material having the same conductivity for heat as glass. These boxes or trucks are constructed so as to prevent dispersion of heat at their sides, and as each is filled with glass articles it is withdrawn from the kiln to cool from two parallel surfaces only By this means ideal plates are formed, which are treated like the solid plates for the production of homogeneous tempered glass in bulk. Glass railway sleepers, tempered on Mr. Siemens' plan, have been introduced in England, and have been put in actual use on one or two railway lines. TESTS OP THE SIEMENS' GLASS. A number of tests were made of these sleepers, at one of which it was shown that their average breaking weight, when resting on supports 30 inches apart, was 5 tons. At another time a plate of Mr Siemens' toughened glass, 9 inches square by 1 inches thick, imbedded in gravel ballast 9 inches deep, and having on its top a wood packing one-eighth of an inch thick and a piece of rail, was subjected to the action of a falling weight, the blows being delivered on the rail. The weight was 9 hundred-weight, and blows were successively delivered by letting this weight fall from heights of 3 feet, 5 feet 6 inches, 7 feet, 10 feet, 12 feet 6 inches, 15 feet, 17 feet 6 inches, and 20 feet. Under the last-mentioned blow the rail broke, the glass, however, being uninjured. A higher fall could not be obtained, and a greater weight was not available. A smaller section of rail was substituted for that previously employed, and the glass was broken by the second blow of the 9 hundred-weight falling 20 feet, the plate being driven through the ballast into the hard ground. A cast iron plate, 9 inches square and one-half an inch thick, tested in a similar way, broke with a blow from the 9 hundred-weight weight dropped 10 feet. USES OF SIEMENS' GLASS. Mr. Siemens writes me, under date of January "29, 1881: Extensive works are about to be established in England for carrying out my process and for producing the glass to be tempered. These works will at the start comprise furnaces capable of producing 50 tons of glass per day, and will be arranged in view of being doubled aud trebled in a short time, it being confidently expected that a large demand will arise for strong glass as a substitute for wood, brass, cast-iron, stone, and other substances, in the condition of railway and tramway sleepers, gas-, water-, and drain-pipes, eava troughs aud gutters, millstones and crushers, tiles for roofing, facing walls and flooring, plates for floors of bridges, tanks, and cisterns, ship lights, telegraph insulators, etc., for which applications tempered glass will offer the advantages of economy in first cost and greater durability over the materials now usually employed. COST OF SIEMENS' GLASS. The cost of glass toughened on Mr. Siemens' plan is stated to be about the same per ton as that of cast-iron ; but as its specific gravity is only about one-third that of iron, the cost of any article of given dimensions is, of course, materially less. The material has as yet been too recently introduced, and too little is known of its characteristics, to enable any very decided opinion to be formed as to its future capabilities ; but the results of the experiments so far made are certainly of a very promising character, and the further development of its application will be watched with much interest. GLASS FROM BLAST-FURNACE SLAG. The process of manufacturing glass from the waste cinder or slag of iron blast-furnaces is simply the utilization of a substance which already contains many of the ingredients of glass by adding to it those materials necessary to complete the composition. The idea is not a new one. In England, and also ou the continent, a sand prepared by pulverizing slag has long been used as an ingredient in glass- making with much success. It is possible that much of the early glass was metallurgical slags remelted. RELATIVE COMPOSITION OF GLASS AND SLAG. Recent comparative investigation into the composition of glass aud of slag shows that the use of the latter in this manner is not without reason, the two substances being very similar, as is shown by the following table : Constituents. Composition of iron slag (Welsh or Soulh Staf- fordshire). Composition of bottloplass (quantities va- riable). Silica Per cent. 40 Percent. 45 to 60 35 18 to 28 16 6 to 12 | to 7 Alkali tto 2 2to 7 Oxide of iron 1 to 2 2 to 6 MANUFACTURE OF GLASS. 55 A trace of sulphur is also found in slag associated with the lime, but this readily passes away with heat, and is insignificant. The iron, which would seem to be the most objectionable element, while present in too great quantity for the manufacture of perfectly clear glass, is still less than is often required by the glass-maker. The chief points of difference between the slag and the glass are in the silica, alkali, and iron, the slag being too deficient in sand to make a hard glass. ADDITIONS TO SLAG IN THE MANUFACTURE OP GLASS. To make glass of slag of the composition given the additions indicated in the following table should be made : Slag. Additions. Glass. Silica 40 Ferruginous sand 60=100 or 57. 14 per cent. Lime 35 35 or 20. 00 per cent. Alumina 16 16 or 9. 14 per cent. Magnesia 6 6 or 3.43percent. Alkali - 1 Soda 10= 11 or 6.29percent. Oxideofiron 2 From the sand 5= 7 or 4.00percent. 100 175 100.00 Thus by combining with 100 parts of slag 10 parts of soda and 65 of sand the proportions of the lime, alumina, and other constituents are severally altered, and a compound formed of the precise nature required. It is to be noted that the figures come well within the limits of difference found in the analyses of glass given in the previous table. It would seem that the variation in the purity of the slag would interfere with certainty in its use ; but daily analyses of slag at a furnace in Great Britain have shown that its composition is measurably regular, enough so for all practical purposes. USE OF HOT SLAG. To take slag, however, which has cooled, and remelt it in connection with the additions named, would require so intense a heat as to counterbalance all benefit to be derived from its cheapness. A plan was brought to public notice in England in 1876 by which the slag is taken as it comes from the blast-furnace and converted into glass without cooling. Mr. Bashley Britten, the originator of this plan, has established glass works at Finedon, in Northamptonshire, at which the slag from the Finedon furnaces is used. The molten slag is conveyed (presumably in covered iron vessels mounted on wheels) to the glass furnace in the immediate vicinity, and is poured, after the addition of the necessary ingredients, directly into the melting furnace, where, after proper fusion, it is run into another chamber, from which it is drawn by the workmen and fashioned into shapes. The products of these works comprise chiefly such articles as wine and beer bottles, which do not require a colorless glass. This process might be much improved by locating the glass house immediately adjacent to the blast-furnace, from which the slag could be run directly into the melting furnace. In regard to the great economy of the process, Mr. Britten says, (a) referring to the table given above : The above 175 parts or tons of glass \vonld, consequently, be produced with the following economy: One hundred tons of it would cost an iron-master nothing. Instead of the labor of mixing and handling in the usual way the whole quantity of the material, only 75 tons would have to be lifted into the furnace. The only ingredients to be bought are 65 tons of common yellow or red sand, to be had anywhere at a mere nominal price, and 10 tons of common sulphate of soda, which may be bought or made for about 20. per ton. The necessary fuel would be limited to what is needed beyond the surplus heat of the slag to raise only three-sevenths of the glass to the required heat; and it is a question whether the greater part of even this might not be saved by bringing down some of the spare gases from the blast-furnace and ^employing them with regenerators ; if needed, they could easily be enriched with a little added carbon. Against these items there would be a set-off from the cost of removing the 100 tons of slag, which must otherwise be thrown away. Beside this, another and considerable saving would arise from the wear and tear of the glass furnace being lessened, in consequence of four-sevenths of the materials going into them being already fused. Under such circumstances the total cost of the glass in a melted state ready for working is seen to be so extremely small that it is hardly safe to venture to express it in figures ; it scarcely amounts to the value of the commonest bricks per ton. COLOK OF SLAG GLASS. The natural tint of the glass thus produced is greenish, but it can be colored to any required tint, and by careful fining and bleaching it can be produced almost as colorless as common window-glass. A cheaper glass can be made by using more slag and less sand, and with some ores the slag is said to be sufficiently siliceous in itself to be converted into a black or dark green or amber glass. With the simple addition of soda and a little arsenic it becomes transparent and perfectly workable, and may be used for many purposes. Acid, however, corrodes this glass, on account of its want of silica. Glass of superior quality to the first mentioned can also be produced. The constituents of slag, as has been seen, are common to all kinds of green glass, and by diluting them with the usual pure materials to a greater or less extent the compound maybe brought up toany standard short of the purity of color inconsistent with the iron and sometimes manganese in the slag. Should the manufacture of glass in this manner ever be deemed of sufficient importance to warrant the taking of steps to purify the slag, much more might be accomplished. The working qualities of the glass thus produced are excellent, admitting of its being blown, cast, or pressed with great ease, and Mr. Britten's company propose to enter into the manufacture of other articles beside bottle from a material so cheaply produced. a See his paper in Journal of British Iron and Steel Institute, 1876, pages 453-467. 1093 56 MANUFACTURE OF GLASS. CHAPTER VIII. HISTORY OF SOME PROCESSES OF GLASS-MAKING. For many years the question as to whether window- glass was known to the ancients was a matter of doubt and discussion, and it has only been recently that the evidence of its use prior to the beginning of the Christian era has been conclusive. Winckelman, the author of the remarkable History of Art, who was assassinated in 1768, pleaded its antiquity, but by far the greater number of scientific men considered it a modern invention, their view being strengthened by the almost utter absence of any allusion by ancient writers to window-glass and the utter lack of fragments of this glass, though large quantities of pieces of vases and other vessels had been found. This want of allusion and absence of remains shows that at least it was of rare occurrence and use. The first positive evidence of the antiquity of window-glass was its discovery, in the year 1763, in a small chamber attached to the bathing-room of a private dwelling, the House of the Faun, unearthed at Pompeii, " in a window closed by a movable frame of wood, which, though converted into charcoal, still held when it was found four panes of glass about 6 inches square." In 1824, in a room connected with the public baths, " a window 2 feet 6 inches high and 3 feet wide, in a bronze frame, in which were found set four beautiful panes of glass fastened by small nuts and screws, very ingeniously contrived with a view to being able to remove the glass at pleasure," was discovered. Eemains of what is supposed to be window-glass of the Roman period are now occasionally found in the ruins of Roman houses built in England and Italy. Dr. Bruce, in his work on the Roman wall, states that " fragments of window-glass are frequently found at some of the stations", and in 1855 he exhibited at Newcastle samples found in the course of his excavations at Bremenium. It is also certain now that glass was used by the Romans for green houses and for the frames used over plants. The glass found at Pompeii shows by chemical analysis a very close resemblance to the glass of modern days, containing about 69 per cent, of silica, 7^ per cent, of lime, and 17J per cent, of soda, with 3 per cent, of alumina. This glass also contained 1.15 per cent, of oxide of iron and 0.39 per cent, of oxide of manganese, the latter being used probably to correct the color due to the iron. It must not, however, be supposed that glass was used to any great extent in the windows of dwelling-houses at this time. The glass was not blown, but probably cast on a stone, as it is very uneven and full of defects. Before the close of the third century, however, window- glass begins to be mentioned in the writings chiefly of the monks and priests of the time, and mainly in connection with the glazing of churches. About this time reference is made to window-glass by Lactanfius, A. D. 290, who says that "our soul sees and distinguishes objects by the eyes of the body as through windows filled with glass ". Jerome, A. D. 331, speaks of sheets or plates of glass obtained by casting, the casting-table being a large flat stone, and the ordinance of Constantine II, A. D. 337, mentions specularii, who were probably glaziers working in other materials as well as in glass. From this time the evidences of the rise of window-glass multiply. It is reasonably certain that it was employed in the church at Treves early in 420. During the fifth and sixth centuries many large churches were built at Rome and Ravenna which were filled with numerous windows, and in the sixth century the glazed windows in the church of Saint Sophia, at Constantinople, with panes from 7 to 8 inches wide by 9 to 10 inches high, were among the wonders of the East. Indeed, it was the building of churches, or the conversion of pagan temples into houses for Christian worship, that extended the use of window-glass at that time. The Roman priests kept the windows and sometimes the roof of the buildings open to read the auguries, but these the Christian priests closed. Window-glass was used in France as early as the third century, but became more common in the sixth. Late in the seventh century " Abbot Benedict", so saith the venerable Bede, " sent for artists from beyond the seas to glaze the church and monastery at Wearmouth," and York cathedral was glazed about the same time. In the eleventh and twelfth centuries glass was generally employed in the windows of the religious edifices, and it is reported that somewhere about the end of the first thousand years of the Christian era a window-glass works was established at Newcastle-on-Tyne, which proved a failure. From the close of the twelfth century the use of glass for windows became more and more common. The earliest glass used for windows was undoubtedly cast, that used at Pompeii having evidently be$n cast on a stone, on the same principle as plate-glass is made at the present time, only it was not polished. It thus appears that, though rough cast plate-glass was for a long time believed to be a modern invention, it really is the oldest method of making glass for windows. This was, however, probably in the twelfth or thirteenth century, or perhaps earlier, abandoned for blown window-glass, and was revived and virtually rediscovered in France in 1688 by Abram Thevart. He obtained a patent for thirty years for the invention, and erected works in Paris, where plates were cast of the then extraordinary dimensions of 84 inches long by 50 inches wide. This works was transferred to Saint-Gobain, which has since become celebrated for its plate-glass. Disputes arose between Thevart's company and a company of Venetian workmen who were manufacturing blown plates near Cherbourg, and Thevart's company was bound not to cast any plates whose dimensions should be less than 60 inches in length and 40 in breadth. To end the rivalry the two companies were consolidated. Two years, however, from the consolidation 1094 MANUFACTURE OF GLASS. 57 \ the company was iu a state of insolvency, and many of its furnaces were abandoned. Blanconrt gives a different account of the invention of plate glass, and ascribes it to the accidental spilling of some liquid glass from a crucible upon the ground. The metal having ran under one of the large flat stones with which the place was paved, upon taking up the stone a piece of plate-glass was found under it. This is stated to have been two hundred years before Blancourt wrote in 1699. The first English establishment of any magnitude for the manufacture of glass was begun in 1772 or 1773 at Ravenshead, at which date "the Governor and Company" "of the British Plate-Glass Manufacturers" were incorporated for the purpose of manufacturing plate-glass in England, and as late as 1832 this was the only establishment in that country. Since that time, however, a number of works have been established. The oldest plate-glass works in Belgium, we believe, dates from near the beginning of the present century, while that of Germany has been in existence but a few years. As noted, it is very difficult to say when blown window-glass was first made ; but one of the earliest notices of it is by the monk Theophilus, in the thirteenth century, who, in his Essay on Divers Arts, gives an account of a method then employed of blowing glass, which is a perfect description of that used at the present time. For many years the factories at Venice were renowned for their blown window-glass, and iu the seventeenth century workmen from its houses were scattered in various parts of Europe and taught many of the glass- workers of the different countries the method of making cylinder-glass. Nesbitt also states that window-glass was made in Germany at a very early period, and it also seems, from a statement quoted elsewhere regarding the windows of Beauchamp chapel at Warwick, that window-glass was made in England, probably blown, in the fifteenth century. Mr. Chance states that the manufacture of blown window-glass in England existed in the fifteenth century, and perhaps even prior to that period ; but the glass then produced was of a very inferior description, and the first works of note established in England were those of Sir Matthew White Ridley & Co., on the river Tyne, at Newcastle, about the middle of the seventeenth century. VASES, CUPS, AND OTHEK HOLLOW WAKE. As has already been noted, the earliest records of glass-making (those on the tombs of Beni-Hassan and at Memphis) show unmistakably that the art of glass-blowing was well known at the early period at which these tombs were built. One of these figures illustrates two glass-blowers, with their blowing irons or rods in their hands, heating the glass, which has evidently been gathered, in a small U-shaped furnace. Another drawing represents two men blowing a vase. From that day to this the production of various kinds of hollow ware has not ceased. An immense number of articles of this character, including vases and cups of all sizes and almost all shapes, from those of the most common description to others showing the most exquisite art, as instanced in the Portland and the Naples vases, and bottles of all forms and decanters, have been found. Indeed, so common and persistent has been the manufacture of these various articles, that the history of ancient and modern glass is chiefly the history of the manufacture of hollow ware, and, as we have entered so fully into the statement, nothing more need be said here. LEAD GLASS. The invention of what was so long known as flint-glass, and now generally termed lead flint, to distinguish it from the lime flint of the glass houses of to-day, is an English invention. Its production was a necessity arising out of the use of coal in the place of wood In the furnace. This substitution of coal for wood affected injuriously the color of the glass, and to overcome the pernicious effects of the smoke the melting-pot was covered with a clay cap, which gave it the shape of a short-necked retort. It was found, however, that though the metal was protected from the action of the smoke, it was also protected from the action of the heat, and it became evident that either the time of melting, as well as the consumption of fuel, must be very much greater, or some flux or alkali must be used which would not deteriorate the glass, but hasten its melting. The flux used was lead, which had to a slight extent been employed on the continent of Europe for some time previous in the manufacture of artificial gems : a use which may probably have suggested its employment for the making of flint-glass. The use of lead, however, in the manufacture of glass was not entirely unknown before, as lead is found in many specimens of ancient glass, and Heraclius gives a recipe for making glass with lead. There was also a glass, known as the Jewish, made with lead in the Middle Ages. M. Peligot, however, reviewing these facts, comes to the conclusion that there is no proof that the true flint-glass was known to the ancients, and that to the English should really be attributed the honor of having created in their flint-glass a new product, which, by the progress made in the quality and selection of the materials used in its fabrication, has become without dispute the most beautiful glassy substance which we know, aud which it may be possible to produce. The date of the introduction of the manufacture of flint-glass with lead is placed by M. Bontemps about 1635 ; Nesbitt suggests that it may have been 1615. THE USE OF MOLDS is generally believed to have been a comparatively modern invention; but, as is shown in the chapter on ancient glass, it is evident that some of the vases used in very remote times were not blown, but were cast or molded over a sand or clay core, which was afterward broken up. It also seems that the so-called Roman molded glass, which was supposed to be a modern invention, was well known to the Romans, as specimens exhumed in the city of London prove. At what time, however, the modern method of using molds in the production of various forms of hollow glass was first introduced is not known, though it is evident that the use of these has largely increased within the years since the introduction of the ase of the lever-press for molding or pressing glass. 1095 58 MANUFACTUKE OF GLASS. PRESSED GLASS. One of the most important inventions of recent times, especially in the line of cheapening glassware, has been the production of what is generally known as pressed glass. This is an American invention, and the right of this country to the honor of its production has not been called in question until recently. Lardner, in his Cabinet Cyclopedia, published in 1832, which has a very complete resume of the methods of making glass in use at that time, has not even a suggestion of the pressing process. Pellatt, in his Curiosities of Glass-making, published in 1849, says : The invention of pressing glass by machinery has been introduced into England from the United States of America. It has not, however, realized the anticipations of manufacturers; for, by the contact of the metal-plunger with tlfe glass, the latter loses much of the brilliant transparency so admired in cut-glass ; hence it is now chiefly used for common and cheap articles. The process of rewarming or fire-polishing after the pressure has somewhat remedied this defect. Eecently, however, an attempt has been made to deprive the American glass manufacturers of the credit of this invention. The London Pottery Oazette, in a recent issue, says : There seems to be a general impression that pressed glass was first made in the United States. This is an error. The addition of the ring to give the thickness was undoubtedly an American invention; and this discovery, trifling in itself, opened up the pressed trade in a remarkable way by enabling the lever used in modern pressing to force up the metal sharply, so as to give it the appearance of cut- glass, as well as to closely imitate cut-glass patterns. Many in the English glass trade are living who remember the pressed square-footed ales and goblets. These are as old as the end of the last century, and were very fashionable with our ancestors. At first they were cut over, but they perfected the make so that they were simply cut at the bottom to take off the overplus. ANCIENT PRESSED GLASS. It is undoubtedly true that glass was pressed before the invention of the American lever-press, and one of the earliest specimens, bearing an inscription from which its date may be ascertained, is the lion's head, now in the Slade collection in the British museum, which was found many years ago at Thebes. This is evidently a piece of pressed glass, or glass pressed in a mold. In the British museum are also many pipces of glass found at lalyssos, in Ehodes, chiefly disks, all of which have evidently been produced by pressure with a mold or die. There is no doubt that the Venetians were acquainted with pressed glass; but, notwithstanding this, the invention of what is now known as pressed glass is undoubtedly American. The same line of reasoning that is adopted to prove that this is not an American invention would also prove that lead-flint glass was not an English invention. Lead was used to make glass centuries before the invention of lead-flint in England, but the English are none the less entitled to the credit of the discovery of that beautiful, brilliant ware that we know- to-day as lead-flint glass. Glass was no doubt made by pressing many centuries ago, but the invention of pressed glass, as it is understood to-day, the use of a mechanical press with mold, plunger, lever, etc., is due to American ingenuity. Pellatt, when referring to specimens of the embossed and pressed glass of the ancients, says: (a) "No machinery was used by them in producing 1 any completely pressed hollow vessel or utensil at one operation." It occurs to me that if Mr. Pellatt, with all of his knowledge and information regarding ancient glass-making and his years of practical connection with the business in England, ascribes the invention of modern pressed glass to Americans, his testimony cannot be impeached. HISTORY OF THE INVENTION. The invention of the. American press is ascribed to a Massachusetts carpenter in the town of Sandwich, about 1827, who, wanting an article of glassware made for some purpose, went to Mr. Deming Jarves and asked him if he could make the article desired. Mr. Jarves told him that it would be impossible for the glass-blowers to make such an article. The carpenter, who was of a mechanical turn of mind, asked if a machine could not be made to press glass into any shape. This idea was scouted at first, but upon second thought Mr. Jarves and the carpenter fashioned a rude press and made their first experiment. This machine was intended to make tumblers, and when the hot molten glass was ponred into the mold, which was to determine whether glass could be pressed, the experiment was witnessed by many glass-makers of that time. They were nearly all of the opinion that the experiment would come to naught, and were greatly amazed when the result demonstrated that it was possible to press glass. From that time the manufacture of articles of glass by the use of pressing machines gradually developed, until to-day the bulk of the glassware produced in this country is made with presses. The first tumbler manufactured in the rough improvised press, alluded to above, remained in Mr. Jarves' possession for many years, and then passed into the hands of John A. Dobson, a well-known glass dealer in Baltimore, and was exhibited at the Centennial Exhibition by Hobbs, Brockunier & Co., when it was accidentally broken by Mr. John H. Hobbs. The London Pottery Oazette, to which we have referred above, in an article claiming the invention of pressed ware for England, says: "The first pressed tumbler was undoubtedly English, and was made about 1836." As Mr. Jarves made his pressed tumbler in 1827, as described above, we think that the evidence is conclusive that the first pressed tumbler was not English, but American. The result of this American invention in cheapening glass has been most marked. By the use of iron or other metal molds immense quantities of the same article can be produced at a very low rate. This invention has in fact revolutionized the whole system of flint-glass manufacture, and has made it possible for all to possess for common use glass that in gracefulness of form and beauty of design and material was formerly within the reach of only the niost wealthy. a See Pellatt's Curiosities of Glass-making, page 122, note. MANUFACTURE OF GLASS. 59 CHAPTER IX. ANCIENT GLASS. DISCOVERY OF GLASS. But little is known of the early history of glass-making, and absolutely nothing of the method and date of its discovery. The story told by Pliny, (a) and repeated substantially by Tacitus (6) and by Strabo, (c) of its accidental discovery by some storm-driven Phoenician mariners while cooking their food on the banks of the river Belus, (d) is not entitled to the least credence. It is impossible that the high temperature necessary to the production of glass could have been obtained in the manner described in these fables. It is true, however, that a small spot at the mouth of this river supplied a most excellent sand, which was used not only by the Phoenicians, but by many other ancient glass- workers, and even by the Venetians in latter times. This fact, coupled with the excellence of the Phoenician glass and the commercial enterprise of the people, which carried the products of their manufactories to all lands, may have given rise to the story related by Pliny, and thus for a time robbed the Egyptians of the credit of a discovery which is undoubtedly theirs. PROBABLE METHOD OF DISCOVERY. While nothing positive is known of the method of the discovery of glass, it is not improbable that it was in connection with tbe older art of metallurgy, (e) Many metallurgical operations produce in their vitreous slag a coarse colored glass that may have led to the manufacture of glass as a direct product. All of the oldest specimens of glass are colored, and, so far as these have been analyzed, the coloring matter is metallic. The extreme variability in the composition of this antique colored glass led Klaproth to the conclusion that many of the specimens are merely metallurgical slags remelted. It is also true that much of the ancient glass is " cast." These facts certainly indicate, if its discovery was not due to this older art, that metallurgy had an important influence on early glass-making. EGYPTIAN GLASS. The earliest evidences of the existence of the art of glass-making are found in Egypt. It is impossible, however, to surmise even at what time it began to be made in that country, aside from the certainty that the art antedates by many centuries the time of its earliest inscriptions and specimens. Egyptian chronology is so uncertain, that the same events are assigned by different Egyptolpgists to periods thousands of years apart. Inscriptions, paintings, and the glass itself, however, indicate its manufacture at least from 4,000 to 6,000 years ago. (/) Rawlinson, (g) a most conservative authority, states that "glass was known in Egypt as early as the Pyramid Period", which he places at 2450 B. C. (h) That at this early date the art of glass-making had reached a high degree of perfection and development seems beyond question. The art of blowin g glass into bottles, fashioning it into vases and drinking-cups, pressing it into various shapes, especially figures of deities, sacred emblems and coins, forming it into huge masses for pillars, adapting it for mosaic art, coloring it to imitate precious stones, the color being of surpassing brilliancy, working it into beads or necklaces, these and similar processes were well known and practiced with great skill. It would seem impossible that the processes necessary to the production of these forms of glass could have been developed without centuries of practice. The invention of the art of blowing glass, which is unmistakably figured on the tombs of Mastaba of Tih, at Memphis, and on the tombs at Beni-Hassan, (t) is as remarkable as the discovery of glass itself, and would indicate an advance in the art that, in that day of slow development, must have required many centuries to evolve. The manufacture thus early begun was continued by Egypt far into the Christian era, and under the various dynasties and rulers, both native and foreign, it continued to flourish. When Egypt passed under the dominion of Rome, its glass houses found in the palaces and villas of the the imperial city a larger and more profitable market for their wares, and even as late as the third century its glass works were still in operation, an ordinance of Aurelian providing that glass should form a part of the a See Pliny's History, book xxxvi, chap, xxvii. 6 Histories, book vi. c Geography, book xvi. d This river runs along the base of Mount Cannel, and empties into the Mediterranean near the modern city of Saint Jean d'Acre. e Metallurgy is one of the arts the invention of -which is ascribed by the Egyptians to Osiris, and while the first man was living copper and iron were melted and worked (Gen., iv : 22). Some writers incline to the opinion that the discovery of glass was in connection with the art of pottery in making the glassy glaze. / Among the earliest traces of glass are those found in the ruins of Memphis, built by Menes, first king of Egypt, whose reign Manetho places at 5004 B. C. The mummies in the tombs of this city wear necklaces of paste-glass beads. Glass-blowing is unmistakably figured on the walls of the tomb of Mastaba of Tih, belonging to the fifth dynasty, or, say, 3900 B. C. This is the earliest representation of glass yet discovered. g See Origin of Xations, p. 56. For further account of glass and glass-making in ancient Egypt, see Wilkinson's Manners and Custom* of the Ancient Egyptians, vol. iii, p. 58, and Rawlinson's Herodftus, 2d ed., vol. ii, p. 292. Pellatt, in his Curiosities of Glass-making, gives beautifully colored lithographs of some of the glass found in Theban tombs. See also Glass in the Old JTorld, London, 1882. h The enumeration of articles put into the west pyramid mention " glass which might be bended and not broken ". i The tomb is supposed to be of the time of Osirtasan I, some 2500 to 3000 B. C. A late number of the Saturday Rcrific, discussing the antiquity of glass, says of the Beni-Hassan inscription: "A much older picture, which probably represented the same manufacture, is among the half-obliterated scenes in a chamber of a tomb of Tih, at Sakkara, and dates from the time of the fifth dynasty, a time so remote that it is not possible, in spite of the assiduous researches of many Egyptologists, to give it a date in years." 1097 60 MANUFACTURE OF GLASS. Egyptian tribute. Coins and tokens of as late a date as the eleventh century are in the Museum of Paris, and a basin of the same century, and lamps of the fourteenth, all the products of Egyptian glass houses, are still in existence. This long-continued practice of the art of glass-making in Egypt was probably due to the possession by the Egyptians of a great abundance of the essential materials, sand and soda, the latter, which was of excellent quality, being found native on the shores of its lakes. lu a valley abounding in these lakes extending northwest from Memphis the Egyptian expedition of Napoleon I found remains of ancient glass furnaces. In this locality, at the " very gates of the lakes of Nitre", the priests of P'tah or Vulcan, who were constantly engaged in experimenting, placed their glass factories, and Kawlinson states that their ruins may still be found. These glass works, however, were not confined to this valley, but were situated also in the Delta and along the Nile valley. Those of Alexandria, however, were the most famous, especially for the production of colored hollow glass and mosaics. PROCESSES OP EGYPTIAN GLASS HOUSES AND CHARACTER OF THE GLASS. The processes used by these early glass-makers were, in many respects, similar to those of the present day. The "batch" was melted in crucibles, and the glass-blower's tool pictured on the Bern-Hassan tomb might well be taken as a representative of those in use at Pittsburgh to-day. Cast glass appears to have been a common product both of the Egyptian and the Phoenician glass houses, and molds were also used both for blowing and for pressing. Some of the hollow ware gives evidence of having been made on wire molds, and other specimens indicate that the glass was molded around a core or "former" of sand. Pressed glass, however, was not made as American pressed glass is formed, a die being used, into which the glass was pressed, or the die was pressed into a mass of pasty glass. The perfection to which these processes were carried, however, will not compare with that attained to-day. Egypt in the days of its best glass-making could not produce a cast plate approaching in size, purity of the glass, or brilliancy of surface those of Saiut-Gobain, nor would her blown and pressed ware approach that of the United States; but it must be conceded, that some of the specimens of ancient glass that have been preserved, (a) especially such as are evidenily the result of careful, patient manipulation, are unsurpassed by the products of our modern glass-houses, as they not only display a high degree of art, but give such evidence of exquisite skill and a knowledge of the most refined and delicate processes that even now they excite unbounded admiration. Among these products may be mentioned embossed and molded reticulated vases, glass mosaics, imitation pearls, glass pastes in several colors, precious Stones, glass eyes, the "ut'a" of mummies, bottles, etc. This perfection, however, is only seen in articles of luxury, and indicates a degree of skill on the part of the workman that justly entitles him to the title of an artist in the highest sense of the word, and the product to be termed a work of art. While all this maybe said of the skill displayed in working the glass when made, the "metal", as glass itself is technically termed, was decidedly inferior to that of the present day. White glass, as we understand whiteness, was unknown, and the clear, white, brilliant flint-glass of our works of to-day would have excited astonishment in the Egyptian and Phoenician glass houses. Most of the specimens that have come down to us from these ancient glass works are articles of luxury, and therefore might give rise to the belief that most ancient glass was of this character; but such is not the fact. Glass of an inferior quality, for common use, was largely produced, and it is probable that it was much more extensively employed bj the ancients than it is in our time, (b) They had no porcelain, and were forced to use metal vessels or those of glass for many of the uses for which porcelain is now employed. COMPOSITION OF EGYPTIAN GLASS. The early Egyptian, as well as other early glasses, appears from its analysis to be a soda-lime glass, the Egyptian containing from 70 to 72 per cent, of silica, 17 to 20 per cent, of soda, and 5 to 8.J per cent, of lime, with some iron and alumina. Its composition is very similar to plate-glass made without potash, containing, however, more impurities. PHOENICIAN GLASS. Second to Egypt in the antiquity, extent, and character of its manufactures of glass, if indeed it did not for a time surpass it in the excellence of its products, was Phoanicia, that wonderful country which gave us letters, and whose nautical skill and commercial enterprise made, the Mediterranean, evep in Ilomer's time, a "Phoenician lake". The renown of the workmen of Phoenicia at an early date is evidenced in the selection of Hiram of Tyre, the artificer, whom Hiram the king loaned to Solomon for the ornamentation of the Temple. Both Tyre and Sidon were famous for their glass, and the beautiful hollow ware made by them was universally celebrated in the ancient world. As already noted, the river Belus, which was near the northern boundary of Phoenicia, furnished a sand of excellent quality, which added largely to the renown of Phoenician glass. Mr. Nesbitt (c) thinks that among the earliest products of Phoenicia in the art of glass-making are the colored beads of opaque glass in great variety of color and pattern, called by the Ashantees "Aggry" beads. These beads have been found in all parts of Europe, in India, and in many parts of Asia and Africa, (d) their wide dispersion, as well as the abundance of other forms of glass that are probably of Phoenician origin, bearing evidence to the extent of this industry, a These are chiefly articles of luxury or personal ornament, and have been largely preserved through the custom of burying with the dead articles which the deceased regarded highly, or which were used constantly. 6 Sec Wincklenian's Origin de Vart. c South Kensington Museum of Art Hand-looks : Glass, by Alex. Nesbitt, F. S. A., page 13. d These are the "Glaiu ueidr" (adders' eggs) and the "Gleiui na Droedh" (Druids' beads) of Wales and Ireland, which aro regarded with superstitions veneration by the peasantry. 1098 MANUFACTURE OF GLASS. 61 and there is good reason to think that many of the glass vases found in tombs in the countries washed by the Mediterranean are the products of Phoenician work-shops, rather than of those of the country in which they are found. CHARACTER OF PHCENICIAN GLASS AND PROCESSES EMPLOYED. Speaking of the character of Phoenician glass and the processes known and practiced, Kenrick says : They knew the effect of an addition of manganese to the frit of sand and soda in making glass clearer. They used the blow-pipe, the lathe, and the graver, and cast mirrors of glass. They must also have been acquainted with the art of imitating precious stones and coloring glass by means of metallic oxides. The " pillar of emerald" which Herodotus speaks of (ii, 44) in the Temple of Hercules at Tyre, "shining brightly in the night," can hardly have been anything else than a hollow cylinder of green glass, in which, as at Gades, a lamp burnt perpetually, (a) Rawlinson says regarding Phoenician glass-makers: What was the amount of excellence which they attained is uncertain; but the fame of the Sidonian glass in early times would seem to imply that they surpassed the artists both of Assyria and Egypt. (6) LATE PHCENICIAN GLASS MANUFACTURE. As in Egypt, the manufacture of glass was continued in Phoenicia, especially at Sidon, far into the Christian era, even as late as the twelfth century, at which time it appears to have retained some of its ancient reputation. The art also seems to have found a place in the industries of the other Syrian cities. In the twelfth century some Jews of Antioch were known as glass-makers. In the fourteenth century Damascus was the chief seat of glass-making in the East, and as late as the seventeenth century glass-making is mentioned among the industries of Smyrna. GLASS-MAKING IN THE OTHER ANCIENT MONARCHIES. In following the history of glass-making, there is little to note after leaving the glass houses of Egypt and Phcenicia until we reach those of Rome. The other great monarchies do not appear to have become celebrated in this art, as the specimens found in their buried cities do not furnish sufficient data to enable the formation of any j udgment as to the extent to which glass-making was practiced, and but little as to the character of the glass. ASSYRIAN GLASS. Layard found in the ruins of Nineveh, which was destroyed 625 B. C., a number of specimens of glass, among which were a glass lens and a small vase or bowl of a transparent green glass with tlie name and title of the Assyrian monarch Sargon (719or 12'2 B. C.) This was blown in one piece, and was then shaped or hollowed by a turning machine, and is regarded as the earliest specimen of transparent glass. An earlier vase, with the name of a Khorsabad king, which Layard found, was stolen or lost. Many glass vases and bottles of elegant shape were unearthed in the same mound, some of which were colored, some ribbed, and others otherwise ornamented. In the palace of Babylon, at Kars, vases and bottles of gilt glass of Assyrian origin have lately been discovered, and M. Botta found among the ruins of Niueveh a round glass bottle or vial with oblong black spots melted into the glass, the earliest specimen of the tear-sown bottles known, the "gafres de Venine". The discoveries at Babylon, while they show the use of glass by its inhabitants, indicate the possession of but little skill, the vessels found being of small size, and the bottles very frequently misshapen. Egypt, however, exported immense quantities of small glass articles to Babylon, and some of the glass found may have been of Egyptian origin. GREEK GLASS. But little is known of the history of glass in Greece. Homer does not mention it, Aristophanes being the earliest writer who refers to it, and the excavations by Dr. Scbliemanu throw but little light on the subject. At Mycena? and Troy he found but few pieces of glass, and these only beads, disks, and pieces of vitreous paste. General De Cesuola brought to light at Dali, in the island of Cyprus, a remarkable collection of Greek glass, containing 1,700 pieces, some of which show great skill; but these are by no means of the earliest Greek period, and are placed by him at later than 100 B. C. Greek art, however, had considerable influence upon Roman glass. The Portland vase, for example, shows marks of Greek rather than of Roman art, though it is not certain that it is of Grecian workmanship. However, it is certain that some glass was made in Greece, and many of the lovely Greek vases of the tombs of the countries of the Mediterranean are undoubtedly of this kind of glass. The Greeks appear also to have used glass occasionally for purposes of architectural decoration during the best period of Grecian art, but not to the extent that it was afterward used at Rome. CARTHAGINIAN GLASS. There is some evidence that Carthage was the seat of glass-making. As is well known, this city was thoroughly Tyrian, and the relations between it and the mother city were very close. It is probable that most of the glass used in the African colony was procured in Phcenicia. At the same time M. Deville, whose contributions to the history of glass have been so valuable, found on a tomb at Lyons the name of " Jules Alexander Africanus, citizen of Carthage, artist in glass". If this artist was from old Carthage, he must have gone to Lyons at least as early as the sack of that city, 146 B. C. Mr. G. Rawliuson attributes to Carthage work- shops many of the glass objects found in the northwest of Africa. The only glass yet found in the ruins of Carthage was in the tomb of Thapsus, but the tomb is probably of the Roman-Carthage period. ETRUSCAN GLASS. But little is known of the state of the glass-makers' art in Italy prior to the Christian era ; but there is evidence from Etruscan tombs that this people, who are noted for their massive engineering works, were acquainted with the use of glass, and some very fine specimens have been brought to light. These specimens, however, are believed not to be of Etruscan origin, and as yet no distinct evidence of glass manufacture among this people has been found. a Kenrick : Phoenicia, p. 249. 6 Eawlinson's Origin of Nations, p. 57. 1099 62 MANUFACTURE OF GLASS. INTRODUCTION OF GLASS-MAKING INTO EOME. It is uncertain when glass-making began to be practiced in Kome. By some it is assigned to 536 B. C., but others place its introduction as late as the time of Cicero, 106 B.C., and state that the first works were near the Flamiuian circus. This latter statement is probably not correct Though Cicero is the first Latin author who refers to glass, it was not, however, until the days of imperial Rome that glass-making in that city attained any importance, either by reason of the character or. the extent of its products. It is probable that a cheap glass had been made in Rome before the time o f the Ca3sars, but the Romans had been dependent upon Egypt for the bulk of their glass, and with the wealth and luxury of the empire came a demand that stimulated its manufacture and use to a degree of development that has, in some respects, never been excelled, and perhaps never equaled. The beginning of the better period of Roman glass dates probably from Augustus. The secrets of the Egyptian glass houses were secured by purchase or by threats, and the long fusion, reinelting the frit, and the slow cooling, that had given much of its reputation to Egypt, became the property of Rome. With this knowledge came perfection, and gold and silver cups gave place to those of glass. Strabo says "that in Rome such improvement had been made in the coloring and process of working, especially in making glass of a crystalline appearance, that you might buy there a cup and dish for half an as ". The degree of skill in manipulation shown by the Roman glass-makers, as well as the taste exhibited in designing, is evident, not only in the stories of the fabulous sums paid for samples of their work, but in the exquisite specimens of their skill that have been preserved, such as the Portland and the Auldjo vases and the Naples amphora. These are as beautiful objects of the glass-makers' art as have been produced in any age of the world, and though at some of the late expositions our modern glass-makers have shown most elegant work in similar style the work of the Romans has rarely been excelled, (a) AMOUNT AND VARIETY OP THE PRODUCTION OP ROMAN GLASS HOUSES. If these vases and other similar works show the skill attained and the elegance and variety of the products of the Roman glass houses, the prodigious quantity made is evidenced by the wonderful abundance of the fragments of glass found even now, not only in and around the ancient, city, but in all parts of the world where the Roman legions penetrated. Nesbitt states that in the winter of 1858-'59, during a residence of four mouths at Rome, he saw in the hands of dealers fragments of at least 1,0 10 to 1,200 vessels of colored glass, for the most part the crop of that season's discoveries. (6) The number of specimens of Roman glass that have been found in Germany, France, Spain, and especially in England, is very great, the museums of those countries abounding in examples, and even now in some of them it is no uncommon occurrence to bring to light glass of the Roman period. The use of glass in Rome was not only very extensive, but entered into use for some purposes to a much greater extent than in modern times. For domestic purposes, for architectural decoration, and for personal ornaments, it was used far more extensively than with us, and so common was its use, and so largely and cheaply was it produced, that, as stated by Strabo in the passage above quoted, a cup and a dish were sold for a coin worth a little less than a cent. LATER GLASS-MAKING. As stated, it is uncertain when the art was introduced into Rome. It was probably derived from Egypt, but it did not reach perfection until after the beginning of the Christian era. A company of glass-makers established themselves in the city in the reign of Tiberius, and were assigned a street near the Porta Capena. In the succeeding reigns marked improvement was made, and in A. D. 220 glass-making had become of so much importance that Alexander Severus levied a tax upon its manufacture in common with other industries, which lasted until the time of Aurelian, if not later. Pellatt thinks that this tax was one of the causes of the transfer of the art to Venice, (c) but the transfer is more correctly ascribed to the incursions of the barbarians, and the dispersion of glass-makers attendant upon them. BYZANTINE GLASS. With the decline and fall of the city of Rome under the torrent of the German and Hunuish hordes the manufactories fell into comparative neglect and were confined to articles of every-day use. When Coustantiue the Great, about A. D. 330, made Byzantium his capital, he attracted to the city, with other tradesmen, the glass-makers of the world. In the first half of the fifth century the Emperor Theodosius exempted the glass-makers from all taxation. In the commencement of the eighth century Justinian II furnished the Caliph Walid with glass mosaics for a new mosque at Damascus, and in the middle of the tenth century Romanus II sent presents of glass to Cordova; indeed, so extensive was its manufacture at Byzantium that one of the gates leading to the port took its name from the adjacent quarter in which the glass houses were situated. As has been noted, many of the Byzantine artisans came originally from Rome, and brought with them the traditions and customs of the art as it had been practiced there. These, as was customary in this early period, were handed down from father to son. In the new Rome of the East glass-making for a while assumed a front rank among the arts, but from the specimens that have come to us it is evident the skill and splendor of the Roman period was not reached, though for five hundred years at least Byzantium secured and held the markets of the world. This art, with others, however, fell under the adverse influence of the bigoted emperors of the East, and the ancient a The reproductions of the Portland vase in jasper ware by Wedgwood are well known, but its reproduction in glass by Mr. John Nort4iwood, of Wordsley, England, is not so noted. 6 South Kensington Museum Art Hand-book: Glass, by Alex. Nesbitt, F. S. A., page 19. Those interested in the character of Roman glass and its manufacture will find in this work a very complete description. c See Curiosities of Glass-making, page 8, note. 11 'JO MANUFACTURE OF GLASS. 63 traditions were wholly lost. The glass that belongs probably to the later period shows but little of the elegance of form and the skill in manipulation of the early Byzantine and later Roman, and the weakness of the later days of the empire of the East had impressed itself upon its art, and with its fall its artisans were scattered, many seeking the shores of the Upper Adriatic to renew their art and restore some of its lost glory in the rising city of the refugees, Venice. EARLY GLASS-MAKING IN OTHER COUNTRIES. The details of the manufacture of glass in other countries prior to the Middle Ages are imperfectly known. Pliny states that the glass works of Gaul and Spain were established before those of Eome, and it may be possible that this is true, as in the days of the later republic and early empire Rome was too intent on extending its conquests to give that attention to the arts, other than those connected with war, which it afterward bestowed upon them. Wherever the Romans extended their conquests, however, in the western part of Europe, glass is found to a considerable extent in the ruins of their occupation. GLASS IN FRANCE. M. Fillou considers that the manufacture of glass in France began at Poitiers (a) in the second century, (b) These factories were active in the Roman and Prankish periods, survived the Norman invasion, and were left a legacy to the gentleman workers of the Middle Ages. In many tombs of the Gallo-Roman period in the neighborhood of Poitiers large quantities of vases of varied form, and sometimes of delicate and careful workmanship, are found ; but the amount found in these and other tombs of France can only be described as immense. Abbe" Cochet states that 20,000 vases were found buried in the cemeteries at Terre-Nigre, Bordeaux, and in many of the tombs glass vials, children's glass toys, beads, twisted sticks, and tiny glass vases, some not exceeding half an inch high, were very common, all indicating the extensive scale upon which the industry was operated. In the Boulogne museum are preserved some curious barrel shaped jars of a low-grade glass quite green in color, bearing the mark of the imperial factory at Frontincennes, at Foret Eu, which is supposed to have been started in the second century, and was the school shop of all the Norman factories of later times. It is still a great factory, and must surely be about the oldest in the world. It is impossible to give a suggestion even of the styles and character of early glass found in France. As Christianity advanced and spread over Gaul the character of the glass changed, and in this way its history can be, in a measure, traced. Its use for church purposes also became established, a pope in the year 197 having ordered that wine should not be consecrated, as heretofore, in a wooden, but in a glass vessel. Glass chalices were used in the fifth century, but at last glass became so common that it was not deemed costly enough to celebrate this mystery, and the church found it best to interdict its use, though glass vessels were still used as late as the tenth century. M. Fillou says that the written documents connected with glass works begin in the ninth century. Normandy was the first country where special privileges were given to glass-workers, and in the tenth and eleventh centuries the first dukes of Normandy bestowed special glass-making privileges on four families attached to their persons, these families continuing the manufacture of glass and enjoyed their privileges up to the last century ; and to this day descendants of one of these families, the Brussards, are to be found as glass-makers. SPAIN. If Pliny's statement quoted in connection with France be true, glass was made in Spain before it was in Rome. As to the localities of these early woiks, Mr. Nesbitt quotes Sinobas as authority that in the Ibero-Roinan period " glass was made chiefly in the valleys which run from the Pyrenees to the cost of Catalonia near the Ebro, also in Valencia and Murcia. Ruins of furnaces still met with in these parts are small in diameter". It is believed that the manufacture continued to exist under the Gothic kings, though others are of the opinion that the art did not survive the invasion of the barbarians. There is evidence that in the seventh, tenth, twelfth, thirteenth, and fourteenth centuries glass was made in various parts of Spain. An edict of 1324 banishes all glass ovens from inside the city of Barcelona, and after this date large quantities of glass seem to have been manufactured in Spain, both for home use and exportation. GERMANY. In Germany also the influence of Rome on the early glass is marked, and it is probable that glass was made in the vicinity of Cologne, Treves, and other places near the Rhine during the Roman occupation, but many questions in connection therewith are as yet unsolved. As to the glass of later times there is similar uncertainty. The drinking glasses found in the Saxon graves of Germany are similar to those found in France and England, but it is undetermined whether these were made in the countries in which they were found, or are all the product of one of these countries, and if so, which one. It seems probable, however, that the art of glass-making was not wholly allowed to die out alter the Roman dominion had passed away. The early glass of Germany was inferior in color and ornamentation to that of its more southern and artistic rivals, but it was superior to them in hardness. The first notice of glass-making in Germany in any document yet published is that to the Bishop of Mainz, elsewhere referred to, in which the Abbot of Wearmouth, England, wrote about the middle of the eighth century, asking him to send him workmen who "can make vessels of glass well". Window-glass was also made in Germany at a very early period, and mirrors were made as early 'as the twelfth century. The use of the tin amalgam is claimed as a German invention of the fourteentk century, and German authors claim the invention of painted glass for their workmen. a Soc GJagsin the Old fTorld (page 126), to which I am indebted for much of the information about early French glass. b This can hardly be so if Pliny's statement istrne. 1101 64 MANUFACTURE OF GLASS. BRITISH ISLANDS. Though the evidence seems to indicate that glass was made in England by the Eomans, it is not as yet quite fully determined that such was the fact. Beads and glass vessels of various kinds are found in tombs of the Eoman period, and fragments of ornamented glass, and even of window-glass, are often met with in tho ruins of towns and villas; but the similarity in most instances of these to Roman glass lead to the belief that they were imported. The probabilities are that, if glass was made in England by the Romans, it was of the coarser kind, the finer articles being the product of other countries. The remains of a glass furnace found at Buckholt in 1860, however, if it was of Roman origin, which is doubtful, would prove that colored and ornamented glass was made in England in the days of the Roman occupancy. It is worthy of note that some authors claim that glass was made in Britain in pre-Roman times; but if it was, it must have been of the coarsest and most common kinds. In Kentish graves, dating from about the time of the conversion of the Saxons to Christianity, many vessels of glass, mostly the peculiar elongated tumblers, are found, which Nesbitt thinks there is some reason to believe were made in England, though they resemble greatly French and German drinking vessels. At what time the manufacture of glass became firmly established in Britain is not known. In A. D. G70 an attempt was made to establish a glass factory at Newcastle-on-Tyne, but it was a failure, and eigbt hundred years passed before the attempt was renewed but in A. D. 675, when Benedict made glass for his monastery at Wearmouth, he imported workmen from France, who were probably skilled in making cast, not blown, glass for the windows, and eighty years later the Abbot of Wearmouth asked the Bishop of Mainz, in Germany, to send him a maker of glass vessels. For some centuries from this glass-making seemed to languish in England. Little ancient glass is found in Scotland. Rome had but little foothold on its shores, and but few fragments of Roman glass have been found. Even the Druids left but few of their paste beads to be preserved in tombs. No record of glass-making in this country exists until 1620. In Ireland there are more evidences of early glass-making than in Scotland. The art seems to have been practiced at an early period, and mosaic glass dating as early as 1112 exists. Some chalices are also in the inaseum of the Irish Academy that are supposed to date from the ninth and tenth centuries. PERSIA, that ruled Egypt so long, carried away captive its most skilled workmen and artists and employed them in building and decorating their famous cities, Persepolis and Susa, and among the ruins of these cities to this day are found fragments of mosaics and other glass, evidently the work of these Egyptian captives. At least 400 B. C. the Persians made glass, as the Athenian ambassadors to Ecbatana drank " wine out of glass and golden cups", and the remarkable cup of Chosroes I (A. D. 532) proves that the art was practiced long into the Christian era; and even to the present glass works are in operation. CHINA. The same mistiness that surrounds everything in connection with the arts of this mysterious empire attaches to glass-making. There seems some reason to believe that glass was made in this country before the Christian era, though it does not appear to have attained much importance. The ancient books state that mirrors were made from pebbles and materials obtained from the sea and reduced to ashes, which is a fair description of glass-making. A factory still in existence in Shan-tung is believed to date as far back as the third century. INDIA There are few traces of the manufacture of glass in India. The remark of Pliny that Indian glass was the finest, being made from crystal, is now believed to refer to Chinese glass, as no examples of early glass of undoubtedly Indian origin have yet been found. CHAPTER X. MODERN GLASS. MODERN GLASS-MAKING DATES FROM VENICE. We have dated the history of glass-making from the workshops of Venice and its island of Murano. It was in the glass-houses of that " gentile island", (a) as Howell terms it, that the art that produced the beautiful and exquisite forms of Roman glass was revived, and from its " whole street of glass furnaces" came the knowledge and inspiration as well as many of the workmen who carried its manufacture into many of the countries of Europe, and laid in these countries the foundations of the glass industry that has continued until the present time. Venetian glass did not, however, at once attain the full measure of its reputation. For many years after the establishment of the industry in that city Egyptian, Phoenician, Roman, and Byzantine glass were those of most repute in the markets of the world, while the earlier products of the Venetian glass houses were of a greatly different character from those that in the sixteenth century gave Venice such renown. a See Howell's Familiar Letters. First letter dated Venice, May 20, 1621. MANUFACTURE OF GLASS. 65 INFLUENCE OF BARBARIANS UPON GLASS-MAKING. Glass-making, with all other arts, felt the influence of the barbarian deluge and that strange stupor that marks the centuries from the close of the fifth to the close of the eleventh. The demand for glass for other than the most common uses quite ceased when the barbarians conquered Rome and appropriated its wealth. The glass works of the imperial city were broken up and the workmen, for the most part, slain or scattered, while those that continued the art, from lack of opportunity, soon lost their cunning. Only in one branch did any of the former glory remain: the manufacture of mosaics and painted glass for windows. Here, as in so many of the arts, the church saved glass-making from perishing from the earth. REVIVAL OF ART INFLUENCED GLASS-MAKING. Such was the condition of glass manufacture when the works of Venice began to assume importance; but as the eleventh century drew to a close the great cities of Germany and *Italy, with their opportunities for commerce and the arts, arose, and among them the republic city of Venice, and the artisans in glass of reputation were attracted to this rising city and shared in the great art revival of the Italian Renaissance. The false and debasing canons of the art of the dark ages were cast aside, and from the study of the pure and simple antique came those great works in modern glass that are regarded as masterpieces in form and color. EARLY VENETIAN GLASS-MAKING. It is not known when glass began to be manufactured in Venice. The Venetians place the date as early as the fifth century, but there is no evidence of its existence earlier than the eleventh, with the exception of certain mosaics that may be of Byzantine origin. In the thirteenth century the art had grown to considerable magnitude, and about the middle of this century codes of rules for regulating glass- workers were drawn up. In 1291 the Council of Ten, to guard against fire, ordered that the glass furnaces in the Mty should be demolished, but that they must be reconstructed in the district of Venice. This led to the establishment of works at Murano. This edict was afterward modified so as to allow the manufactories of small wares to remain, provided th^re were fifteen paces left between the works. In 1275 the council prohibited the exportation of glass-making material, and in 1295 renewed it ; in addition, it levied a heavy fine upon all glass- makers who should leave Venice to practice their art in other cities, and in 1474 death was made the penalty. At this time the fame of Venetian glass had become so great that extraordinary efforts were made to induce workmen to leave Venice and establish its manufacture hi other countries, and England, Spain, and Flanders all endeavored to secure workmen to build up their glass works. This was the occasion of the edicts of the great council to which we have referred, (a) In the sixteenth and seventeenth centuries glass-making reached its highest development in Venice, from which time it began to decline, and in the eighteenth century England, France, and Bohemia began to compete successfully with Murano, interrupting its trade, and the works became idle, the. glory of Venetian glass departed, and only beads and common ware came from the shops that for five centuries had given an incontestable superiority to Murano. This lethargy remained until the art was recently revived through the efforts of Dr. Salviati. EXTENT OF THE INDUSTRY AT VENICE. The extent to which this ait was practiced in Venice can be inferred from the fact that in the time of its prosperity 8,000 men were regularly employed, and the glass houses extended in an unbroken line for a mile along one of the streets of Murano. The manufacture was not carried on, as HOW, in large establishments, but by artisans working on a small scale, which may account for the great variety of form. For the most part, the glass, with the aid of the pincette, was shaped before the blow-pipe, and the forms of the product were vessels, window-glass and mosaics, optical glass, mirrors, and beads. CONDITION AND RESTRICTION OF WORKMEN. Mr. Jarves, in his admirable paper in Harpers Magazine on Venetian glass, in speaking of the causes that produced such a body of workmen and maintained the superiority of its glass through so many centuries, says : As early as 1500 there were twenty-four glass houses at work at Murano, each having more or less its speci alty. The furnaces in general were small. During the period of its greatest prosperity (the fifteenth, sixteenth, and seventeenth centuries) Murano counted 30,000 inhabitants, now reduced to about 5,000. Each owner of a factory was obliged to contribute annually a certain sum into a common fund for tho succor ot me unfortunate of their own class, poor and infirm artisans, or those out of employment, and for the maintenance of the schools of inventive design. No apprentice could be admitted as a master-workman before passing a strict examination in his art and proving his skill in the manufacture of certain objects. The candidate was elected into the body of masters by their secret ballots. Each factory was subject to inspection, night or day, by certain officers, whose duty was to see that the work was regular according to the statutes, to note the quantity and quality of the objects, and that no glass in fragments or cnllet be exported. Proprietors and master-workmen of tea years' experience, if they honorably failed and had no other means of subsistence, were entitled to pensions of 70 ducats annually. When there were more master-workmen than could be profitably employed, it was forbidden to increase their number from the apprentices until there was a real call for new hands. Whoever became a member of the guild was obliged to take an oath of fidelity. No one who had not a regular discharge from his employer could be received into the service of another, and every proprietor was obliged to seal hia cases with his own trade-mark. It was forbidden to employ strangers uuder any pretense. If there were not enough of the Muraiiese at times for labor, or to exercise the art, Venetians only might have the privilege, but they must be duly qualified. No employer could hire a master-workman who was in debt to another of the guild. Such were some of the regulations to keep the art in a high state of efficiency, and which for more than five centuries gave it an incontestable superiority in its special aim over other establishments in Europe. In fine, Murano became as artistically famous for its glass as Urbino, Pesaro, Gnbbio, or Chafiagiola at the same time for majolica, but with far greater commercial development. alt is impossible to follow the history of glass-making at Venice. An admirable account will be found in Nesbitt's "Glass" in the South Kensington Art Sand-book. 1103 66 MANUFACTURE OF GLASS. GLASS IN THE DARK AGES. As has already been stated, the barbarian invasions and the destruction or decadence of the Roman power brought with it a decline in the art of making glass. The conquerors of Rome had but little in common with the taste and refinement that have sought and preserved as precious treasures the dainty and exquisite gems of the glass-maker's art of which so many evidences remain, and under their early dominion it seems probable that only the commoner and more useful forms of glass were produced. Thus it would appear that while glass-making in most of its higher and artistic processes was a lost art for some centuries, it was not wholly forgotten, but in all countries where Roman enterprise had established glass houses the art was preserved. It seems certain that France, Germany, Spain, and possibly England, made glass during the period of its decadence, and thus kept alive the practice of the art that was afterward, under the influence and example of Venice and by the art of its workmen, to grow in most of these countries into the glass works of to-day. FRANCE. It is reasonably certain that the manufacture of glass has not been wholly lost in France at any time since the days of Pliny and the Romans. The glass works at Poitiers, which were of so much importance, and which, if the evidence of the tombs in its neighborhood is to be taken, produced such enormous amounts of glass during the Roman period, seem to have maintained a continued existence and to have been of no little account even into the eighteenth century, when the industry declined under the competition of the glass houses of La Rochelle and Nantes. There is no doubt, however, that the works of Poitiers felt the same adverse influences as fell upon those of all Europe, and also that the new skill and the advance in its art that marked the close of the sixteenth century came from Venice. In 1572 one Salviati, " gentilhomine de Murano," came to Poitiers to practice his art, and was undoubtedly accompanied or followed by others. Their presence is evidenced in the efforts to produce fine and ornamented wares, and enameled glass, pretty drinkiug-cups, vases, and bottles, both white and colored, were some of the products of the period that foil owed the coming of these gentlemen of Murano. Glass-making, however, was by no means confined to the neighborhood of Poitiers, as works were erected at Provence as early as the thirteenth century, and attained considerable skill in the sixteenth. Large quantities of glass were made in Normandy in the twelfth century, and the le Valliant family, upon whose ancestors Charles VIII, in 1490, conferred the " privileges de verrerie", have continued its manufacture up to the present century. In the Boulogne museum are some barrel-shaped jars from the imperial factory of Froutincennes, which is supposed to date to the second century, and is still a great factory. In 1598 Henry IV permitted two " geutilshomme verriers ", natives of Mantua, to establish themselves at Rouen, in order to make "verres de cristal, verres dore~s, emaulx, et autres ouvrages qui se font a Venise", and in 1603 the same king established works at Paris and Xevers. Colbert, the great finance minister of France, who did so much for French industry, wrote to his ambassador at Venice in 1664 requesting him to procure workmen for a glass house; but the story runs that the ambassador replied if he did so he ran the risk of being thrown into the sea. In 1665, however, eighteen Venetian glass-makers were obtained, and the manufacture of mirrors was begun at Pans. Colbert united this with another existing at Tour-la-ville, near Cherbourg, and in 1693 the united works were transferred to Saint-Gobaiu, where the manufacture is still carried on upon a very large scale. It was about this date also that Thevart rediscovered the method of casting plate-glass, and succeeded in making plates 84 by 50 inches. For a time in the eighteenth century France seems to have lost the art of making "vases de verre", as in 1759 the Academy of Sciences offered a prize for the best essay on the means by which the art could be revived. If this was true, France has abundantly recovered its prestige, and Baccarat wares are to-day the rival of any. France seems also for a while to have been behind its neighbors in the manufacture of blown window-glass. Even in the beginning of the eighteenth century the French imported from Germany and Bohemia whatever window-glass of the better sor' they used. In 1740 an association for the making of French cylindrical or broad window-glass was formed by Drtxtiuvaux, workmen being drawn from Germany, and a manufactory was established at Lettenbach (Saint-Quirin), which attained good repute, and became later the parent factory of the modern French, Belgian, and some English p ate-glass works. A late German writer, from whom the above statement is derived, states also regarding the influence of Germany on French glass-making : By holding closely together, and by steadily and firmly repelling French apprentices, the workmen who had been attracted frou Germany kept off the competition of the natives of the country during a long time, and, as a consequence, even at the present day , among the French artisans in glass a very great majority hear German names, while German words and phrases are very numerous among the technical terms of the art. The first lead-flint glass melted in France was by Lambert, at Saint-Cloud, in 1784. In 1790 the crystal manufactory of Muensthal, or Saint-Louis, was founded. In 1823 d'Artigues bought the glass manufactory of Saint- Anne, and changed it into the world-famous " Crystallerio de Baccarat". SPAIN. In this country, as in France and Germany, glass was made in the Roman period, and it is probable that its manufacture did not wholly cease in the dark ages, though this is not as well settled as in the case of France. Seflor Juan F. Riano (I quote from Nesbitt), in the introduction to the catalogue of art objects of Spanish production in the South Kensington museum, has supplied much information with regard to the later history ot Spanish glass making. He commences the modern history of the art in Spain by stating that an Arab author of 1104 MANUFACTURE OF GLASS. 67 the thirteenth century says that Mercia was renowned for the fabrication of glass and pottery, of both which materials large vases of the most exquisite and elegant shapes were made by the Moors; and that "Almeriawas also famous for the fabrication of all sorts of vases and utensils, whether of iron, copper, or glass". The making of glass at Barcelona was probably of equal, if not of greater antiquity. In a municipal edict of 1324 is a prohibition that the glass ovens should be inside the city. In 1455 permission was granted to the "vidrieros" to form a corporation under the patronage of Saint-Bernardino, and from this period some of the members figure as holding municipal charges. Jeronimo Paulo, who wrote in 1491 a description in Latin of the most remarkable things at Barcelona, says " they also send to Eome and other places many glass vessels of different sorts and kinds, which may well compete with those of Venice". Marineus Siculus, who writes at the beginning of the sixteenth century, says ''that the best glass made in Spain is that of Barcelona"; and Caspar Baueiros, in his Chronographia, published at Coimbra in 1562, mentions that excellent glass was made at Barcelona, almost equal to the Venetian. From the beginning of the seventeenth century there are several allusions to the merit of the Barcelona glass, and to the vast quantity which was exported. Glass was also made at Cadalso, in the province of Toledo, as early as the beginning of the sixteenth century ; other works were at Torre de Esteban, Hambroz, in 1680, which gave the most brilliant results, and at Eecuenco, in the province of Cuenca, in the beginning of the sixteenth century, and in 1722; also in the seventeenth century at Valdemaquada, in the province of Avilo. In a royal schedule, dated 1680, stating the prices at which things were to be sold in Madrid, glass made at Barcelona, Valdemaquada, and Villafranca in imitation of the Venetian is mentioned; and the glass of Valdemaquada was sold for a higher price than that made at the other places. There was also an important manufactory at La Granja, famous for fine chandeliers, mirrors, and engraved glass. What we have of the products of these factories scarcely seems to support the assertion that the glass rivaled Venetian, though several pieces in the collection formed by Seuor Eiano closely resemble the products of Mnrano. One reason of the success of so many factories making glass of the same character as Venetian, and of the failures of England, was, no doubt, that the Spanish, in the interior of a country ill provided with the means for the transport of such an article, did not sustain so severe a competition as the English factories. Spain is not a country very productive of fuel, and doubtless when the glass houses had burned up the wood in their neighborhood the manufacture ceased to be profitable. It would seem that, except near the coast, the glass must have been made with potash obtained from the lees of wine or from burnt wood, as the transport of soda, either from Egypt or from the coast, o a which it could be produced from seaweed, would have been extremely costly. At Barcelona and other places on or near the coast soda may, of course, have been used. GERMANY. Though the specimens found in the neighborhood of Cologne, Treves, and other places bordering on or near the Ehine indicate that glass was made during the Eoman occupation, it is not clear that it continued to be manufactured after this time. From the tenth to the fourteenth century, however^it is certain that window- glass was made in considerable quantities, and the letter of Cuthbert, Abbot of Wearmouth, to Lullo, Bishop of Mainz, about the middle of the eighth century, would indicate that glass vessels were made as early as this. Vessels of the sixteenth century, however, are quite common, among them the "wiederkoms", some of which are twenty inches high, the oldest of which the date can be ascertained being 1553. From the wood-cuts in Agricola's De Re Metallica, published in 1556, we may gather some idea as to the products of German glass houses at that time, which seem to be vases, bottles, and retorts, but he does not indicate that any fine glassware was made in Germany. About the year 1600 glass was extensively made in Bohemia and other parts of Germany, and the fine crystal glass of Bohemia may date from this time. In 1609 glass-cutting was practiced, and some of the work in this century was said to be of remarkable fineness and delicacy. The invention of etching with fluoric acid is ascribed to Henry Schwanhard in 1670. The Electoral glass works, on the Isle of Peacocks, near Potsdam, was established in the eighteenth century, and, under Kuuckel's management, gained great celebrity for its gold ruby. Then, under the ministry of Danckemiann, French workmen were drawn into the country, and under Moor's management the manufacture for blown plate-glass was established in 1695 at Neustadt-on-the-Dosse, whose workmen, when, after Danckelmanu's overthrow, ifeustadt for a time fell into stagnation, founded, at the instigation of the elector, Lothar Franz, the mirror manufacture at Lohr-on-the-Mayn, which in course of time attained to great distinction. Similar manufactures were soon afterward established at Schleichach, near Wurtzburg; at Fahrafeld, near Vienna ; at Grnenplan, near Hanoverian Miiideu; at Senftenberg, in the elect or ate of Saxony; and at Alten-Kronau, in Hesse. Finally, in 1710, through the influence of Count Eechtskron, mirror or plate-glass casting \vas introduced from France, and a mirror foundery was established after the model of Saint-Gobain at Xeuhaus with French workmen, which, though protected in every way and defended by prohibitive regulations, in 1728 passed over to the Austrian state. In fact, plate-glass casting did not prosper in the beginning any better in Germany than in France. As little successful, too, were the attempts in various places made to obtain useful flint-glass for optical purposes, and it was not until 1806 that Utzschueider, at Benedictbeureu, produced such an article of the kind as answered the ends for which it was required. BOHEMIA. It was in Bohemia that Venetian glass first found a successful rival, this rivalry being at first manifest in the quality of the glass itself. Venetian glass had never been noted for the purity of the metal, and 70 i\r M 1105 f>8 MANUFACTURE OF GLASS. witli their purer materials the Bohemians were able to produce a much whiter glass than the Venetians could witr their somewhat impure sand and soda from seaweed. The Bohemian crystal, therefore, soon became noted, and for centuries was held in high estimation, and only lost its pre-eminence with the invention of English flint. But it was not alone in the purity of its glass that Bohemia became the successful rival of Venice, for in the beginning of the seventeenth century the decoration of glass by engraving, probably a Bohemian invention, which soon became the fashion, sadly interfered with the products of the Italian city. The cut-glass was especially noted, and so sharp and injurious did the competition become that one Briati, a glass-maker of Murano, determined to go to Bohemia and learn the secret, and accordingly worked for three years in a Bohemian glass house as a porter, returning to Venice in 1739 to obtain a patent for ten years for the production of glass after the fashion of Bohemia. The excellent character of Bohemian glass is noticeable to this day, and the skill of the workmen who robbed Venice of its glory has not departed from the forests of Bohemia. THE Low COUNTRIES. But little is known of the glass industry in the Low Countries until a very recent period, though it is positive that glass was made in Flanders as early as the fourteenth century. " Crystal of Antwerp " is mentioned in 1509, and in 1563 glass is mentioned as among the articles of export from Antwei'p to England. In the first half of the seventeenth century several Murauese glass-workers obtained privileges for making glass, and in 1642 John Savonetti was permitted to establish glass-making at Brussels with an absolute prohibition of all imports. In the sixteenth or beginning of the seventeenth century were produced the glasses on which are to be seen the paintings of John Steen, 2/erburg, and others. In comparatively modern times the *vorks of Belgium have been quite noted, at one time the product of vases and such ware surpassing the French. Ib Is stated that the celebrated Baccarat works were established by Belgian workmen. BRITISH ISLANDS. As has already been noted, there is considerable doubt as to the continued existence of the English glass works after the period of Eoman occupancy, and it was not until the beginning of the fifteenth century that they awoke from their period of actual or comparative idleness. In 1447 John Prudde, of Westminster, covenanted to " use no glasse of England " in executing the windows of the Beauchamp chapel at "Warwick, which would indicate that glass was made in England at that time. The vast palace of Henry VIII that formed one of the attractions of the Field of the Cloth of Gold in 1520 was built of wood and glass. The glass-maker's art, however, did not advance rapidly, for, in 1557, according to quaint Thomas Charnock : As for glass- makers, they be scant in the land; Yet one there is, as I do understand, And in Sussex is now his habitation ; At Chiddingsfold he works of his occupation. In 1589 George Longe petitioned for a patent, in which he stated that there were fifteen glass houses in England. These he propoged to reduce to two and rebuild the balance in Ireland, whereby the'wood of England would be saved and that of Ireland wasted. In the reign of Queen Elizabeth some persecuted Protestants from France came to Newcastle and worked at their trade of glass-making at the Close Gate, and afterward went to Tyne. In 1662, Fuller states that "coarse glass-making was, in this county (Sussex), of great antiquity", and another, writing of the manufacture of -glass in that county, says : Neither can we match the pnrity of Venice, and yet many green ones are blown in Sussex profitable to the makers and convenient to the users thereof. INFLUENCE OF VENICE ON ENGLAND. As the use of glass began to increase in England adventurers from Venice and other portions of the continent sought to advance their fortunes by bringing schemes for making glass of superior quality before the English government. In 1550 eight Muranese glass-makers, imprisoned in London, who had been induced to go there by offers of no small sums of money, and who had heard of the edicts of the Council of Ten, petitioned the council to be allowed to work out the money received. On June 13, 1550, the council, to gratify the king, decided to allow this. For the next few years evidences of the influence of Venetian workmen multiply, and the art began to assume importance. Early in the seventeenth century sea-coal began to be used. Mansel secured the patents for its use in 1616, and set to work making both window-glass and glass vessels of various kinds, having brought a Venetian to aid him. About this time one of the most important advances or discoveries in modern glass-making, and one of the very few real discoveries of modern time, was achieved (the manufacture of lead flint), and the English workman had this beautiful and brilliant glass to stimulate his exertions. In 1677 the Duke of Buckingham made at Lambeth " huge vases", "clear, ponderous, and thick as crystal," as well as looking-glass plates and windows for coaches. In 1673, at the ".Italian glass house at Greenwich ", " glass was blown of finer metal than that of Murano at Venice." The revocation of the edict at Nantes in 1685 drew a number of glass-workers to England, and the manufacture continued to improve, until, in 1736, Dr. Pococke considered English glass to be superior to that of Bohemia, and only inferior to that of the royal Prussian glass houses. From this time the manufacture of glass was of growing importance, and the details need not be given. RUSSIA. In Russia the glass industry first obtained a firm footing in the course of the seventeenth and eighteenth centuries, having been introduced by German and Bohemian workmen. As regards the details of its 1106 MANUFACTURE OF GLASS. 69 introduction and establishment, slight information has ever reached the public. We have historical mention of a glass manufactory at Schabino, near Jamburg, in 1717, and in 1720 an establishment for the making of French mirrors and dishes and plates of crystal was opened at Kiew. In the last year of the last century we find mention of Lund's plate-glass manufactory at \Vyborg, in Finland, and of Bolew's similar establishment in the Eussian government (province) of Kajasan. At the same time the imperial mirror foundery at Saint Petersburg had already begun work ; and the imperial crystal and hollow-glass manufactory, which exists at the present day, had been already established at the same place. In 1792, with the aid of workmen from Gruenenplan, the foundation was laid of the Amelung mirror manufactory at Dorpat, near which place, in 1780, a similar establishment had been set up by Major Lauw, but its existence had been brief. CHAPTER XI. THE PRESENT CONDITION OF GLASS-MAKING IN EUROPE. CHIEF GLASS-MAKING COUNTRIES OF EUROPE. The countries of Europe most largely engaged in the manufacture of glass at the present time are England, France, Belgium, Germany, and Austria- Hungary. Each of these countries not only manufacture most of the kinds of glass needed for its own use, but the factories supply the non-glass making countries of the world and supplement the production of each other and of such other states as manufacture to some extent. This is especially true of the finer grades of glassware (table and ornamental glass) and plate-glass. EACH COUNTRY HAS A SPECIALTY. While each of the countries named produces most, if not all, of the chief varieties of glass, each one has become especially skillful in the manufacture of some particular variety, and has secured and maintained a pre-eminence in its production that has enabled it to command the markets of the world. ENGLAND'S SPECIALTIES. England is especially noted for the beauty, purity, and brilliancy of her flint ware, which is without doubt the purest and most brilliant made. Individual glass houses in other countries may produce flint that may be compared with some English flint, but none, as a commercial product, that can rival it, while in no other country does the bulk of the flint-glass made approach even the bulk of that made in England. These remarks apply to lead-flint only, as the American lime-flint is probably, so far as the metal is concerned, equal, if not superior, to any other. In the blowing, cutting, and engraving of the flint, the regularity and perfection of the work, as well as the beauty and brilliancy of the finished ware, England is unequaled. The exhibit of Thomas Webb & Sous at the Paris exposition of 1878 surpasses in these respects, and in the limpid whiteness, purity, and brilliancy of the metal, all other flint I have ever seen, and was justly entitled to the "grand prix" it received, while the vases engraved by Mr. Xorthwood in the style of the Portland vase equal in workmanship, if they do not surpass, that product of the glass-makers' and engravers' art. Certainly no modern work equals it. FRANCE'S SPECIALTIES. The artistic taste shown in the product of the French glass houses has given French glassware a world-wide reputation. The metal is not as white as that of Bohemia, nor has it the brilliancy and fire of the English flint ; but for elegance of shape, lightness of design, and beauty of glass, all combined, it is unsurpassed. The products of the Baccarat works have been regarded for years as models of taste, and have been eagerly sought for and copied in cheaper wares by the glass houses of other countries. France is also unsurpassed in the manufacture of plate-glass, the product of the Saint-Gobain works being taken as the standard of color, quality, and perfection ; and to say that the plate-glass of any works equals French plate is generally considered sufficient praise, (a) The same artistic taste that has given French glassware so enviable a reputation is displayed in the staining and decorating of window- and plate-glass. The stained-glass windows of French artists show remarkable ability in designing and execution, (ft) The decoration of fancy ware by various methods, especially by enameling and etching, is also carried to a high state of perfection, both as to color and workmanship. BELGIUM'S SPECIALTY. Belgium is pre-eminently the window-glass manufacturer of the world, and though the other countries mentioned above (England. France, Germany, and Austria-Hungary) all make window-glass to a considerable extent, there is not one of them in which Belgian window-glass does not find a market. A large amount, equaling a large proportion of their consumption, is also exported to other countries, and even the United States imported in the fiscal year ending June 30, 1880, 37,927,414 pounds of Belgian window-glass, valued at a Our American works claim to have succeeded in making plate-glass fully equal to the French ; indeed, some -works claim to make better. b Most marked advances in the art of staining windows have been made in the last ten years in this country, and the prodnctio-is of Tiffany and La Farge rival those of the artists of any country. 1107 70 MANUFACTUEE OF GLASS. '$1,230,622. The excellent quality of this glass, as well as its remarkably low price, accounts for this import. The average value of the Belgian window-glass imported into this country in 1880 was about 3| cents per pound. GERMANY'S SPECIALTY. Germany is especially noted in the markets of the world for her silvered plate or looking-glass aud for her cheap table ware and colored vases. The production of mirrors of various grades, largely of the cheaper kinds, in Germany is enormous, and their exportation constitute a large part of her foreign trade. Of the $2,897,747 in value of silvered plate imported into the United States in 1880, $2,746,636 was from Germany. The cheap colored-glass vases of this country were the first (about 1830) to supplant the decorated china vases, which until that time had undisputed sway as cheap mantel ornaments, and she still retains much of the trade in these articles, though other nations manufacture them in large quantities. Germany is also noted for a remarkable ruby glass, which was brought to perfection by Kunckel in 1679. AUSTRIA-HUNGARY'S SPECIALTIES. Austria, or Bohemia in Austria, rivals France in the graceful forms, the variety of shapes, and the beauty of the engraving and decoration of its glassware, and surpasses it in the color and purity of the glass itself. Bohemian glass has been renowned for many years, its workmen apparently inheriting the skill and some of the peculiar processes of manufacture of the Venetians when the cunning of glass-making left the city of the Doges, and it is this cunning in design aud ornamentation that has given it its celebrity. It does not compare with the English flint in brilliancy, and is only equaled by the French in beauty of contour, but in purity, whiteness, and homogeueity of metal it is the best white glass made in Europe, while their success in making glass of intricate design and great difficulty of manipulation makes the Bohemian glass workers second only to those of Venice. VENETIAN GLASS. Though not a large producer of glass, Venice deserves most honorable mention in any statement of the specialities in glass manufacture of the diiferent European nations, and the recent very successful revival of the manufacture of Venetian glass at Murano, that " gentile island which attends the cittie of Venice ", promises to restore to that city the world-wide celebrity of its former days of glass-making. The wonderful color, intricacy of design, and execution of the mosaics ; the pastes, gem-like in color and brilliancy ; the murrhiue of Pliny ; the remarkable enameling of the famous tazze of St. Mark's ; the aveuturiue or imitation gold-stone, with its difficulties in manufacture ; vases in niilleflori, others with metallic flakes and spun and twisted threads of filigree work ; all of these products of the elder Venetian glass houses are reproduced with wonderful fidelity in the modern Venetian glass of the Venice and Murano Glass and Mosaic Company. The glass-bead manufacture of Venice is also a remarkable industry, 6,000,000 pounds a year being produced, the markets of t?he world being largely supplied from this country. GLASS IN OTHEK EUROPEAN COUNTRIES. None of the other European countries are especially noted for their glass, nor is it made to any great extent in any of them. Sweden and Norway make glass of the commoner kmds, window, flint, and bottle, but no plate. Eussia has largely increased its make of glass in the last ten years, but does not yet supply the demand of its own people even for the commoner kinds. Holland makes large quantities of a square black bottle. Of the glass works' of Spain and Portugal but little is known. PLATE-GLASS FACTORIES IN EUROPE. The manufactories of plate-glass are located chiefly in England, France, Belgium, and Germany, (a) In England there are six or seven works, in France seven, in Belgium five, in Germany five, in Eussia one, and in Austria -Hungary (Bohemia) one, possibly two, making a total of twenty-six or twenty-seven. These diifer greatly as to production, most of the English, French, and Belgian works being very extensive, while most of those of Germany and of Eussia and Bohemia are comparatively small. Some blown plate is made in Bohemia, Bavaria, and England, and patent plate in England. PRODUCTION OF PLATE-GLASS. Of these countries France is the largest producer of plate- glass, England the next, Belgium the third, and Germany the fourth. Mr. Charles Coln6(&) estimated the production of Europe in 1877 at 1,800,000 square yards, or 16,200,000 square feet, valued at $12,000,000. (c) This production he distributes as follows : Square feet- France 5,400,000 England 5,400,000 Belgium 2,250,000 Other countries 3,150,000 Total 16,200,000 This production has largely increased since the date named. Mr. Charles Palmer, on behalf of the plate- glass manufacturers, of England, made the accompanying statement regarding the weekly production of polished plate- glass in England, France, and Belgium (d) to the commissioner to negotiate a new commercial treaty with France. a Statistics of the European glass houses are exceedingly difficult to obtain, especially in England. The statistics given will therefore ue regarded only as an approximation unless otherwise stated. 6 See Mr. Charles Colnd's Report on Glass and Glassware at the Paris Exposition of 1878, page 329. Washington, 1881. c Mr. Colu6 places the production of 1860 at 992,000 square yards, and of K67 at 1,100,000 square yards. d See English Slue Book, Commercial, No. 38, 1881, pp. 121, 122. 1108 MANUFACTURE OF GLASS. PLATE-GLASS. 71 WORKS I* BELGIUM. WORKS HI FBAXCE. Companies. Weekly pro- duction in English feet Companies. Weekly pro- duction in English feet Total. Belgian Plate-Glass Syndicate : Floreffe Feet. 25,000 Floreffe (Belgian company), at Jeumont, department du Nord.. Feet. 32,000 feet. 25 000 32,000 Roui .. 15,000 department do Noid. Coorcelles . 20 000 i . ,_. 64,000 Auvelais 10,000 > 80 000 95,000 50,000 32,000 16,000 242,000 175,000 Assuming that these works would average forty weeks' running in a year, and adding to the production of these countries thus found the best estimates obtainable for Germany, Russia, and Austria-Hungary, the production of Europe would be as follows : Square feet. France 9,680,000 England 5,000,000 Belgium 3,800,000 Germany 2,900,000 Russia 250,000 Austria-Hungary 400,000 Total 22,030,000 This estimate agrees substantially with that of Mr. N. T. De Pauw, who estimates the production of Europe at 500,000 square feet a week, (a) PRICES OF PLATE-GLASS IN EUROPE. Mr. Palmer, in his statement to the French treaty commissioner before referred to, gives the following as the prices of plate-glass at the date of his communication : LOXDOX. PARIS. PRICE OF FREXCH POLISHED PLATK. PRICE OF FRENCH POU8BXD GLASS. Saint-Gobain, English taring less 40, 5. and 2| per cent French ****% Ie88 M P er cent - disc< u > t *** preminm " nd TO PP le - Size. Price per foot Size. Supplementary discount. Plioeper foot, net. About 10 feet superficial . .. d. l 1 6 i 10 feet superficial . d. 1 111 About 22 feet superficial 1 64 90 feet superficial 2 A hnnt 33 fp^t Superficial 1 6} 33 feet superficial . ... 2 34 Abont 45 feet superficial 1 7 2 31 1 7t 2 74 WINDOW-GLASS IN EUEOPE. It is impossible from the data at hand to even estimate the production of window-glass in Europe or the number of factories at work. Xo statistics, not even an estimate, has been obtained from England. In Belgium there are 61 window-glass factories, with 216 furnaces, of which but 138 were in operation recently. These works produce from 3,600.000 to 4,000,000 boxes of glass of 50 feet each annually. In France there are from 25 to 30 furnaces, producing from 800,000 to 900,000 boxes annually ; and in Sweden, 4 factories, with an annual production of 40,000 boxes ; in Norway, 1 factory, no product given ; in Italy, 12 factories. In Austria-Hungary, 63 factories make window-glass ; in Germany, 86, while from Switzerland, Spain, Portugal, and Russia I have no statistics, though window-glass is made in all of those countries. a Report of the Tariff Commission, page 941. Washington, 1882. 1108 72 MANUFACTUEE OF GLASS. FLINT- AND BOTTLE-GLASS. The statistics of the manufacture of fliut- and bottle-glass in Europe are even more meager than those of plate- and window-glass. All the information that has been obtained is included under the notes of the manufacture of each country which follow. MANUFACTUEE OP GLASS IN GREAT BRITAIN. The glass manufacturers of Great Britain are, as a rule, extremely chary about giving statistical information concerning their works, and it is a question whether any late complete statement as to the number and production of their glass houses exists. A table published in the factory returns of 1871 shows the number, locality, and employes of the glass works of the United Kingdom at that time to be as follows : Localities. Number. Children. Males up to 18. Males above 18. Females. Total. 24 10 1,113 2 153 401 3 677 37 6 1,530 3,602 927 6 065 Middlesex 16 4 134 319 30 487 g 7 117 277 23 4-4 1 70 243 6 319 Stafford 33 1 808 2 755 312 3 876 9 86 136 5 227 Warwick 47 3 274 874 167 1 318 8 2 56 13' 7 196 York 29 12 877 1 961 138 2 988 19 1 464 1 037 91 1 593 a 63 192 9 264 Total 240 46 5 592 13 680 2 116 21 434 CHIEF LOCALITIES. The chief locality for glass manufacture in Great Britain is in the north of England especially on the Tyne, plate, window, and flint, both blown and pressed, being made in large quantities. Plate is also made at Saint Helen's, in Lancashire, at and near Birmingham, and at London ; flint in London, the Birmingham district, Warrington, etc.; window-glass very extensively in the Birmingham district, and bottles and window-glass near Liverpool. DECLINE OF THE ENGLISH GLASS INDUSTRY. If the statements that are constantly appearing in the English journals devoted to this industry are true, glass-making in Great Britain is not in a very prosperous condition. A correspondent of the Pottery Gazette says : It is a very significant fact that nearly every trade in this country has made gigantic strides in advance during the past thirty-five years, during which time the glass trade has been stationary, if it has not even retrograded in its productiveness, (a) This condition of affairs is especially noticeable in the flint-glass business. The same journal gave recently a list of 30 flint-glass furnaces, containing 296 pots, located in various parts of the United Kingdom, that had become extinct. Commenting upon this that paper says : It is but just to say that some of these houses have removed to more convenient works, to the extent of about 6 or 8 furnaces and 48 or 60 pots ; but still there is a great reduction in the number of works, during which period it must be borne in mind the population has nearly doubled. The following table shows the value of the British imports and exports'of glass for the years 1878, 1879, and 1880 : IMPORTS OF GLASS. 1S78. isn. 1880. Window and German sheet including shades and cylinders 452 202 450 647 476 338 Flint 489 518 174 113 179 503 Plate, silvered or not 233 602 163 064 214 917 Manufactures, nnemunerated, and old broken 879 733 789 006 906 991 EXPORTS OF GLASS. 1878. 1879. 1880. Plate 106, 762 239,747 | 310, 307 99, 068 149, 275 133, 635 230, 537 305,606 113, 255 190, 635 192, 607 248, 694 332,886 147, 321 186, 980 Flint Common bottles Other manufactures, unennmerated Glass of all kinds not of English manufacture It will be noted that the imports of 1878 and 1880 do not differ much except as to flint, which shows a decided decrease, while the exports show in all classes of glass an increase. Part of the decline in flint-glass is no doubt mo a See the rottery Gazelle. London, September 1, 1881. MANUFACTURE OF GLASS. 73 due to the competition oi the cheaper lime-glass, which, for ordinary purposes, is fully as good, and is now made of a superior quality. At the same tim it is true that for beauty and brilliancy no glass can compare with English lead-flint. MANUFACTURE OF GLASS IN FRANCE. For many years France, through the Saint-Gobaiu works, has virtually controlled the manufacture of plate-glass on the continent of Europe, and, to a large extent, its production and prices throughout the world. The Saiut-Gobaiu Company not only own four of the seven French plate-glass works, producing fully 70 per cent, of the total make of France, but they also own the only two important plate- glass works of Germany. On the other hand, however, it is to be noted that two of the remaining three of the Freuch plate-glass works are owned by a Belgian company. It thus appears that the plate-glass production of Europe is largely controlled by two companies, one French and the other Belgian. It is possible that the number of plate-glass works at present in France should be given as eight, as a factory was erected at Saint-Denis, near Paris, a few years since, though I am not advised whether it is running at present. The Saint-Gobain works have made the largest sheets of plate-glass that have ever been produced. At the exhibition of 1878 at Paris an unsilvered polished plate, measuring 21 feet 2 inches by 13 feet 6 inches, was exhibited. A special table had to be prepared on which to cast this enormous plate. The quality of the French plate is most excellent, and is the standard for comparison in all the countries of the world. A considerable amount of the production of this glass is used in the manufacture of mirrors, some 275,000 square yards being ionsumed annually in this way. The manufacture of window-glass in France is relatively of the least importance, the production of plate, flint (lime and lead), and of bottles being greater in value than that of window-glass. According to Mr. Coln, there were in France in 1878 (a) from 25 to 30 furnaces, with 8 pots each, producing from 40,000,000 to 45,000,000 square feet. These are found almost entirely in the north of France, near the coal-fields. Large quantities of round, oval, and square shades, for protecting clocks, artificial flowers, etc., are made in France, the process of manufacture being similar to that of window-glass, the sheets being blown in cylinders of a very even thickness all through. The coloring, staining, painting, and decorating of window-glass is carried on to a remarkable extent in that country, there being in the neighborhood of five hundred establishments in France for thus manipulating sheet-glass, and the French colored sheet-glass is especially notable both for its colors and for their manipulation. The so-called flashed or doubled glass is very common, both in sheet and flint, flint glassware being in some instances coated with as many as four different layers of different colored glass put on very thin and evenly. Most of the stained or colored glass used comes from the departments of the Nord and Pas-de-Calais. The work at many of the establishments has att?oned a high degree of perfection, and the French stained glass, by reason of its artistic excellence and cheapness, is in demand in all parts of the world. As has already been stated, the French glass houses are especially noted for the taste displayed in their flint ware, both lime and lead ; but the quality is not as good as the English, though a marked improvement has recently been made in this respect, and the gracefulness of 'the forms and the beauty of the designs have given French crystal glass a reputation that is unrivaled. The decoration of window -glass with enamel colors in imitation of the antique is also quite an industry in France. Most of the work in the French flint houses is hand-work, the result depending largely upon the manual dexterity of the workman. Pressing on the American system is not employed to any great extent, while that which is made is decidedly inferior to the American. Owing to her wine production, France is naturally a large manufacturer of bottles, producing annually from 125,000,000 to 150,000,000; indeed, the value of bottles made in this country exceeds that of any other form of glass. Some of the bottle works have been established for a long time, one, that of J. Tumbeuf Xeveu et Xeveu, in the Jura, being founded in 1506. It was at this place in 1630 that the first gentlemen glass-blowers (gentilhommes verriers) were made by decree of the king. The following table published in the Report on Glass and Glassware of the Paris Exposition shows approximately the value of the annual production and exportation of glass of French manufacture in 1878: Description. Production. Export. . Crystal $2,200,000 $800,000 2,800 000 1,600 000 5 000 000 1 600 000 3 000 000 600 000 Bottles -. 8 000 000 2 400,000 MANUFACTURE OF GLASS IN BELGIUM. Belgium possesses excellent facilities for the manufacture of glass, and iu some lines, especially window-glass, these facilities have enabled her to produce so cheaply as to command a portion of the trade of the most important countries of the world. Fully two-thirds of the glass made in Belgium' is exported. As is noted elsewhere. Belgium has tive plate-glass factories, producing about 94.0JK) square feet polished plate a year. While some of the plate in Belgium equals the French, this is not true of all manufactured. The production, however, is increasing, and the quality is improving every year. This a Keiiort of Part* Exposition on Glass ~ * sr- ^^ No. of emplov68. Value of prod- uct. i i 35 $27,000 Glassware 2 2 300 86,500 3 1 3 270 86, MO 1 Total < 605 200,000 Of the employes 25 are women and 112 are children. MANUFACTURE OF GLASS IN SPAIN. Though Spain was one of the first nations of western Europe to make glass, the present condition of this industry by no means justifies the promise of its beginning. There existed in Catalonia, Spain, in the last century many works famous for their beautiful glass, but these are nearly all closed. Iii the whole of this kingdom at the present time there are only some 23 or 24 glass houses, making bottles, lamp articles, and window-glass, mostly for local use, though some little is exported. At these factories, also, some rude and strange shaped vessels and drinking-cups are made, and these, compared with the specimens remaining, show that the old forms and the old systems of ornamentation are still in use. GLASS IN HOLLAND. There are in Holland 19 glass works, all but one of which are engaged in the manufacture of the peculiar square glass bottles used for bottling the Dutch spirits. Many of these bottle factories are in connection with the distilleries, and consequently have a steady business, but little affected by foreign competition. The total production is about 19,000,000 a year, all .colored. In addition to these bottle factories there is a glassware works at Maastrecht. The province of Zealand furnishes a substance largely used in the manufacture of plate-glass, "bergasche", supposed to be the remains of a salt-boiling works which once existed in that province. This substance takes the place of soda, but requires especial preparation. GLASS IN PORTUGAL. In Portugal there is one establishment for the manufacture of crystal and fine glass, -and some glass of other kinds is made, but not enough for the needs of the country. CHAPTER XII. HISTORY OF GLASS-MAKING IN THE UNITED STATES. GLASS MAKING IX VIRGINIA AND WEST VIRGINIA. One of the first attempts at manufacturing within the limits of the thirteen original colonies was the production of glass. The hopes of sudden wealth from the discovery of gold and silver, or from finding the fabled passage through this continent to the South Sea, were doubtless the chief causes of the formation of the London Company and its early attempts to colouize Virginia. At the same time this was a commercial venture, with the hopes of profit, and with a shrewdness characteristic of the English merchants, not only of that but of subsequent centuries, they did not forget entirely the possibilities near at hand in their search for what they believed would be greater ones in the near future. The vessel which carried Captain Newport to this colony on his second voyage, in 1608, also brought out eight Poles and Germans to make "pitch, tar, glass, mills, and soap-ashes". Stith wisely remarks that ; ' had the country been peopled they would have done well, but they only proved a burdeu and a hinderance to the rest", (a) After the return from the fruitless expedition to the country of the "Manakins", the president of the colony. Captain Smith, dispersed as many as -were able, some to make glass, and others for pitch, tar, and soap-ashes". Between the arrival of Captain Newport and the return of his vessel, in 1608 or 1609, some glass was made, aud part of the return cargo, the first that conveyed any exports of manufactures from what is now the United States, was the trials of glass thus made. Stith states that the glass house in which the glass was manufactured, and which was probably the first manufactory erected in the English colonies in America, being erected late in 1608 or early in 1609, stood in the woods about a mile from Jamestown. This enterprise was one of some daring. Glass-making at this time was by a Stitb's History of Virginia, page 77. AVilliamsburfr, 1747. 1115 78 MANUFACTURE OF GLASS. no means well established, in Europe. Flint-glass was not yet invented, and plate was not cast, while the art of blowing window-glass and bottles and making glassware was imperfectly practiced in England. Wood, however, was becoming scarce, and the alkalies needed for the manufacture of glass high priced, and those of a good quality were brought from a distance. All of these materials were not only abundant in the new colony, but the wood was a burden and potash could be made readily from the wood-ashes. The great bulk of glass bottles made their importation expensive, and it is'possible that the first glass house in Virginia made bottles only. What window- glass was used was imported. The craze for the raising of tobacco, which had such a disastrous effect upon the colony, interfered with glass- making, and in 1617 Captain Argall, on his arrival as governor, found the glass house fallen to decay, (a) In 1620 an attempt was made to restore manufactures to the colony, and a large number of artisans was sent to V.irginia. In 1621 a roll or subscription was opened to raise funds for the erection of a glass house to make beads for the Indian trade, and Captain Norton and some Italians were sent over for that purpose. The subscribers to these rolls were to participate in the profits. These beads were currency among the Indians. The London Company, in its letter of July, 1621, sent in the ship George, commended this Captain William Norton to the governor. He was directed to be lodged in the Guest House with his "gange" until he had found a convenient place for his furnace, and in the choice of place care was to be taken that he and his "gange" be as secure as possible from surprise, "so that the commoditie of glass and beads should not be vilified by too common a sale to the Indians", (b) At the time of the massacre, in 1622, the glasshouse at Jamestown was destroyed, but it does not appear that these Italian glass-workers were massacred, as they must have been had their glass works been at this place. They are referred to in June, 1622, and again in February 20, 1623, by the governor and council in a letter to London, in which they state that a gentleman who was returning to London would inform the company what had been done. This would seem to indicate that the manufacture of beads was not carried on at Jamestown, but that the house that was destroyed was the first one. What was the history of glass for some years after this date is not, so far as I have been able to discover, a matter of record. No doubt the colonists found that the cheapness of fuel and of alkali was more than offset by the scarcity and high price of labor and its tendency to seek other employment, and it is probable that glass- making was abandoned. The next account of a glass works in Virginia that I have found is of one that was in existence in 1787 at Alexandria. M. De Warville, who visited this state in the fall of 1788, states that this works exported the previous year glass to the amount of 10,000 pounds and employed 500 hands. This is the last notice of a works in eastern Virginia until early in the nineteenth century. Mr. Jarves states that a Dr. Adams, of Eichmond, Virginia, "made large offers of increased wages to the workmen of the Essex-street works, who were induced to abandon their places of work and violate their indentures. They succeeded in reaching Eichmond to try their fortune under the auspices of the doctor. A few years' experience convinced them of the fallacy of increased pay, for, after very heavy losses, the works were abandoned and the workmen thrown out of employ". This is the last record I have been able to find of a glass works in eastern Virginia, or what is now Virginia. In the census of 1810 Virginia does not appear as a glass-making state. In 1815, however, a glass works for making white flint, hollow, and other glassware was established at Wellsburg, in the western part of the state, at which glassware of an excellent quality was produced. In the census of 1820 a glass works is reported in Brooke county, which was no doubt the Wellsburg works. It made that year $20,000 worth of glass, had $12,000 capital, and paid out $8,000 for wages and $12,000 for material amd contingent expenses, or exactly the value of product. It employed 14 men and 12 youths. In 1827 it is reported that glass decanters of great beauty and solidity were made at these works, "while white flint and green glass wares made within a few years rivaled the foreign." At the tariff convention of 1831 there were two flint-glass furnaces, with 12 pots, reported in operation at Wellsburg, Pennsylvania, evidently a misprint for Virginia, and one with 6 pots at Wheeling, Virginia. Two window-glass works are also reported at Wheeling. In 1840 one glass works is reported in Brooke county (the Wellsburg), and three in Ohio county (the Wheeling). Eegarding the history of the Wheeling factories, Mr. W. Leighton, jr., in an article contributed by him to the Wheeling Sunday Leader of March 28, 1880, in some reminiscences, states that The first glass factory built in Wheeling was for the manufacture of window-glass, and the business was commenced some time in the year 1821. I find in the History of the Pan-Handle that "in 1829 a flint-glass house was erected in Wheeling by John and Craig Ritchie, located on the side of the liill opposite the second ward market-house. This establishment was operated for several years with great activity and success, and had a widespread reputation for the manufacture of fine-cut glassware. This success and the unrivaled: advantages for procuring cheap fuel at Wheeling encouraged other firms to embark in the business, and in 1835 the Messrs. Sweeney put a large flint-glass works into operation in the northern part of the town, which was followed in the course of the next few years by the erection of another large establishment at the extreme south end, built by Plunket & Miller, now owned and operated by the firm of J. H. Hobbs, Brockunier & Co.". a Captain Smith, under date of 1615, states that for a long time the labor of the colony had been misdirected in the manufacture f various articles, among them glass. 6 Neal' s Virginia Company of London, page 231. 1116 MANUFACTURE OF GLASS. 79 The veteran glass manufacturers of this country, Mr. J. L. Hobbs, and his son Mr. J. H. Hobbs, of the South Wheeling glass works, have been. I believe, for a longer time uninterruptedly running their furnaces than any other glass manufacturers in the United States. These gentlemen came to Wheeling in 1845 and purchased the glass works built by Messrs. Plnnket & Miller, since which time there has been no break or interruption to Their business. Whether or not the introduction of glass-making at Wheeling encountered the same difficulties as are described to have met Mr. Bakewell at Pittsburgh I do not find set down in the records, but the probabilities are that a similar experience was had. The factories, however, ultimately surmounted all difficulties, and went on to good success. In 1863 the Central Glass Company was established by .1 number of workmen from the South Wheeling glass works and successfully operated. At later dates several other factories have been built in this valley, among which are the Belmont Company and Goblet Company at Bellaire, the La Belle Company at Bridgeport, and the Excelsior Company at Martin's Ferry. Beside these, window-glass factories and lamp-chimney houses have been located here, and the amount of glass business in this vicinity is assuming year by year greater proportions. The obvious reason for the establishment of glass factories in Wheeling has already been mentioned its cheap fuel. This has always been an important consideration; but the success of glass-making here has not been due to this cause alone ; it owes much of it prosperity to the enterprise of those engaged in it. While the first great step of progress in glass-making in modern times, the invention of pressing, is claimed, as before mentioned, to be American, so is the second not only American, but had its origin here in Wheeling. This second step was the improvement in the composition of lime glass, which enabled manufacturers to substitute that material in place of the old flint-glass. For the manufacture of bottles, wiudow-glass, jars, and shades in England and on the continent of Europe lime glass has always been used, and can boast an antiquity perhaps as great as that of flint-glass. The first factories in this country made window-glass, nsing, of course, the lime composition ; the manufacture of bottles followed, bnt flint-glass making was commenced, and, as in Europe, only inferior grades of ware were made of lime glass. In Pittsburgh, at an early period, common tumblers and cheap table ware were made of lime glass, and some improvement had been made in 1864 ; but still the lime goods were so much inferior to flint-glass as not to come in competition with it, their lack of purity and luster being very conspicuous faults. lu the winter of 1664 Mr. William Leighton, sr., of the firm of J. H. Hobbs, Brockunier & Co., made a course of experiments in the composition of lime glass, the result of which was so successful that the manufacture of lime glass was commenced by his firm, and ware was produced equaling in beamy the finest flint-glass. The most important feature in the composition of this new lime batch was the use of bicarbonate of soda in place of soda-ash, until that time universally used in lime glass ; and this use of bicarbonate, and better proportion of all the materials, constituted the improvement, and led to the most important results. As the improved lime glass was much cheaper than flint-glass, being less than half its cost, other factories commenced using the same material and learned the new composition. The ware thus manufactured could only be distinguished from flint-glass by its less specific gravity, and by the peculiar tone of its sonnd when struck, the flint-glass having a full metallic tone or ring, while the lime glass emits a dull, dead sound, destitute of vibratory tone. From the time of this improvement in lime glass the flint-glass factories began to languish. The larger number of them, perceiving that the era of flint-glass was past, gave up the old composition and commenced the manufacture of bicarbonate glass, as it was then called". But a few factories still clung to the old lead-glass composition, fondly hoping, and perhaps believing, that lime glass would run a brief course, and that there would be a return to the time-honored flint-glass. It soon became evident, however, that lime glass had gained the ascendant by merits that would stand the test of time, and those who still persevered in the manufacture 01 lead glass found their ware could no longer be profitably made, and gained the experience that, in an age of progress, whoever clings to the methods of the past will soon be neglected and forgotten. Beside advantage of cheaper material, lime glass has the property of chilling and becoming rigid more quickly than flint-glass, thus enabling, and even compelling, the workmen to finish the ware more rapidly, and hence making a greater production ; and as the specific gravity of lime glass is less than that of flint-glass, articles made of the former have the advantage of this lightness of weight. The result of all these advantages, together with improvements in furnaces, tools, and methods of manufacture, has been to reduce the cost of glassware to about one-fourth part of what it was when the invention and introduction of bicarbonate glass took place in 1864. With this reduced cost, and consequent reduced price, the use of glassware has been extended correspondingly. New factories have been built ; old factories have increased their capacity ; and a snfiicient supply of glassware has been produced to meet the demand which the reduced prices created. N~o kind of ware, even if composed of the most common materials, can now compete in cheapness with lime glass for drinking- vessels and table ware ; while for beauty of material, finish, shape, and ornamentation glassware is more than equal to, and for cleanliness far beyond, any other. Speakiiig of gas furnaces. Mr. Leighton says: Although Wheeling took no part in experimental gas furnaces, yet as soon as it became evident that a safe form of construction had been reached, that form was at once adopted here. The largest gas furnace for melting glass in this country, and probably in the world, was built and put into operation last year by Messrs. J. H. Hobbs, Brocknnier & Co.. at theirSonth Wheeling glassworks, and after six months' trial they were so well satisfied with its results that they put up another of the same form of construction, which has just been completed. GLASS-MAKING IN PENNSYLVANIA. The first mention of a glass works in Pennsylvania is found in a letter written in August, 1683, by Penn to the Free Society of Traders. In this letter he alludes to their tannery, saw-mill, and glass-house, " the last two conveniently posted for water carriage." Where this glass house was located, or for what kind of glass it was intended, is not known; indeed, it is doubtful whether the works were ever used for the purpose for which they were erected. If they were, they proved unsuccessful, as did most of the early glass works in the colonies, and were soon abandoned. () a Budd, who wrote in 1685. does not mention them. Dr. More's letter, printed in 1687, mentions a number of industries, but not glass-making, and the same is true of the pamphlet printed some time in 1691. entitled Lifter* and an Jftfra. Fb)ladelphia, 1833. / See Dr. Dyott's Exposition. 1119 82 MANUFACTUKE OF GLASS. It was stated that this glass was composed of " materials altogether the production of American soil, about 15,000 barrels of rosin from North Carolina being annually consumed as fuel in preference to wood or coal". From 250 to 300 men and boys were constantly employed. In 1833 this works had five furnaces, wood and coal, as well as rosin, being used for fuel. It may be well to follow out the history of these works in this place. They were operated for several years after this until the disastrous failure and conviction of Dr. Dyott in 1838 for fraudulent insolvency, when the works passed into other hands, and after being idle for some years, were leased in 1842 by Henry Seybert, who became interested in the glass business principally for the purpose of assisting Eugene Roussel in obtaining a supply of bottles for the manufacture of mineral or aerated water, then just being introduced into the United States. He also made flint in one furnace. In 1843 they were leased by a partnership, of which Mr. Henry B. Benners, the present proprietor, was a member. This works is still in operation, the oldest glass works in Philadelphia, and probably in the United States, with a record of one hundred and eleven years of work. Returning to 1810, the date of the first census of manufactures, we find reported in Pennsylvania, outside of Allegheny county, five glass houses one in Philadelphia city, two in Philadelphia county, and one each in Lycoming and Wayne counties. The value of the product of the Wayne county works is given at $36,000, while that of the three Philadelphia works was only $26,000. The Lycoming county works, which was probably at William sport, had a product of $20,000. This would indicate that glass-making in Philadelphia was not a prosperous business. At the census of 1820 but one works is reported in Philadelphia county, "a flint-glass works, that had been out of operation for some years ", while in Wayne county a window-glass works, with one furnace and six pots, is reported, which had been "in operation for five years with good success". Jarves also states that in 1820 a number of workmen left the New England Glass Company at East Cambridge, Massachusetts, and established a co-operative flint-glass works at Kensington under the title of the Union Flint Glass Company; but after a few years this works passed into other hands, and the first recorded attempt at co-operative glass-making in this country failed. In 1831, as already stated, the Dyottville works were the most extensive in the country. There was also in Philadelphia a flint-glass works with six pots. No mention is made of the Wayne county works at this time, though it appears at the census of 1840. There were, however, two works in Lycoming county, at Williamsport, one for the manufacture of window glass and the other for hollow ware (green glass, etc.). In 1840, according to the census, there were but two glass works in the eastern district of Pennsylvania: one in Philadelphia and one in Wayne county. But it is not necessary to follow the history of glass in this section further. While there has been glass made in increasing quantities in eastern Pennsylvania since 1840, the industry has not attained the importance it has reached west of the mountains. It may be interesting to state, however, that though window-glass was at one time made in Philadelphia, none has been made in that city for seven years. Of early glass-making in western Pennsylvania quite full accounts remain, and at least four of those connected with the earliest works, Albert Gallatin, Colonel James O'Hara, Major Isaac Craig, and Major Ebenezer Denny, were prominent in the affairs of the nation. Their journals and papers have been saved from the destruction or oblivion that usually overtakes such documents, and from these very satisfactory statements of these early undertakings can be obtained. The generally received opinion for some years has been that the first glass works west of the Allegheny mountains was built by Albert Gallatin at his settlement of New Geneva, on the Monongahela river, some 90 miles south of Pittsburgh. Here Mr. Gallatin established a number of industries, and among them that of glass- making. Various dates have been assigned to his glass works, the most common one being 1787; but the evidence is quite conclusive that this is an error, and that the works was not started until 1797. () Not only is the date usually assigned to this works incorrect, but it is very probable that it is not entitled to the credit of being the first west of the Alleghenies, Craig & O'H.ira making glass about a month earlier, (b) As the Gallatin works was isolated and so remained, not forming, as did Craig & O'Hara's, the nucleus of a great industry, it may be well, though it was not the earliest, to give its history first, that the account of the works at Pittsburgh may be a connected one. The Gallatin works was used for the manufacture of window-glass. The furnace was a small one, with eight pots, using wood as a fuel and " ashes for alkali" . The glass house was 40 by 40 feet, three sides frame and one side stone. The most credible story regarding its erection is that a number of glass- workers, mostly Germans, left Amelung's factory (c) at Fredericktown, Maryland, and crossed the mountains for the purpose of building a glass works at the point that is now Louisville, Kentucky. Gallatiu accidentally met them at Wheeling and persuaded a In Adams' Life of Gallatin, Philadelphia, 1879, it is stated that the business of "glass-making " at New Geneva began " during Mr. Gallatiu's absence in the spring of 1797 ". This is confirmed by Mr. Isaac Craig. (See note below.) 6 I am informed by Mr. Isaac Craig, of Pittsburgh, the grandson of Major Craig, who has iu his possession many of the letters that passed between Major Craig and Colonel O'Hara on the subject of the glass works, and who is one of the best authorities on the history of western Pennsylvania living, that as the result of a correspondence between himself, Mr. Henry Adams, the author of the Life of Gallatin, before referred to, and a son of Mr. Gallatin, he is convinced that the Craig & O'Hara works began to make glass a month easier than Gallatin's. The Pittsburgh works began in 1797 without doubt, and this would fix the date of Gallatin's as 1797 also. Mr. Craig has kindly allowed me free access to his grandfather's letter-books. c See account of this works under "Glass-making iu Maryland". It is probable that Mr. Ameluug was at one time a glass- worker at Pittsburgh. In Ciimiuimfs Journal, about 1807, mention is made of A. F. Ameluug, a glass-worker in Pittsburgh. MANUFACTURE OF GLASS. 83 them to turii back to New Geneva and establish the works there. Mr. Gallatin agreeing to furnish capital and they to do the blowing, (a) The title of the firm at first was Gallatin & Co., but it was afterward changed to the New Geneva glass works. For a time the business was exceedingly profitable, more so, Mr. Adams tells us, than any other of Mr. Gallatiu's enterprises, (b) There were but two, possibly three, other window-glass factories in the country, most of the window-glass used coming from England. These works, as well as Craig & O'Hara's. were on or near the route . of travel between the. East and the rapidly developing West, and the glass commanded a ready market. There seems 'to have been considerable discussion between Mr. Gallatin and his partners, among whom were a Mr. Nicholson and two brothers by the name of Kramer, who were skilled workmen and had charge of the manufacturing of the glass, as to the price at which it should be sold, and it was fixed at $14 a box of 100 feet, (c) though Mr. Gallatin, fearing ruinous competition by reason of the profit at this price, favored a lower rate. The glass, however, by reason of the character of the materials used, was probably of an inferior quality. The works was removed in 1807 to the other side of the Monongahela river, and in 1814 it was operated by Nicholson & Co. (d) As late as 1832 a glass house was reported at New Geneva, and glass was made some years later than this. When the works was finally abandoned I have not been able to learn. In 1796 preliminary steps were taken by Major Isaac Craig and Colonel James O'Hara toward the erection of the first glass house at Pittsburgh, (e) This was also the first works west of the mountains to make glass. Mr. Peter William Eichbaum, a German glass-worker, who was superintendent of glass works at the Falls of the Schnylkill, near Philadelphia, being engaged to direct their erection. (/) Various causes delayed the work, and it was not until 1797 that the active work of building the furnace was begun, when, as appears from a letter written June 12 of that year by Major Craig to Colonel O'Hara, (g) search for coal in the upper part of what is now Allegheny City not showing a vein of workable thickness, a location on Coal Hill, on the south side of the Monongahela river, just above where it unites with the Allegheny to form the Ohio, was purchased, and the erection of the furnace was begun. This site, or part of it, has ever since been continuously occupied by a glass house, the Point Bridge works of Thomas Wightman & Co. occupying it at present. This was one of the first, if not the first works in the United States to use coal as a fuel ; (h) indeed, as late as 1810 coal was not used in any glass works in this country but the Pittsburgh houses, (i) It was not the force 01 circumstances or Irck of wood that led to the use of coal, but it was the deliberate design of the promoters of this enterprise to melt their glass with coal, and it was the character of the coal in Coal hill that determined the location of the works, (j ) The use of coal in the state of the art at this time required considerable determination and risk, and it is to the credit of these gentlemen that they dared use it. The generally received belief that this was the first glass works in Pittsburgh was called in question a few years since by the statement that in 1795 there was a window-glass works, known as "Scott's", at Glass House riffle, on the west bank of the Monongahela. (I;) This is without doubt an error. Mr.Neville B. Craig, in his History of Pittsburgh, speaks of the O'Hara works as " the first glass house here", and as his memory went back distinctly to 1796, if not earlier, it is hardly possible he would not have known of this " Scott's" works if it existed in 1795. It is probable that the works referred to was the "Ohio" works, built about 1800 by Denny & Beelen, which was on the north side of the Ohio, and which gave the name to Glass House riffle, as it appears from a letter of Major Craig's, in connection with the experiment of Mr. Price, that Dr. Hugh Scott, from whom it. got its name, a History of Fayette County, Pennsylvania. Philadelphia, 1882. 6 Life of GaUatin, p. 176. Sir. Adams writes me, however, that the glass works were "a constant matter of anxiety" to Mr. Gallatin. c This does uot seem so extravagant, a price when it is known that at the census of 1810, when there were at least fifteen works in the country making about 5,000,000 square feet of window-glass a year, the marshals estimated the value of the glass at 16 cents a square foot. * d Cramer's Navigator, 8th ed., p. 40. Pittsburgh, 1814. e History of Pittsburgh, p. 27(5. By Neville B. Craig. Pittsburgh, 1851. / I have before me a letter from Mr. Eichbaum to Major Craig, dated Falls of the Schuylkill, August 18, 1796, from which it appears that negotiations had been in progress for some time between these gentlemen looking to the building of the glass house, and "four different sorts of clay" from near Pittsburgh had been sent Mr. Eichbaum for his judgment as to their adaptability for pot-making. He writes they " do not look amiss" with the exception of some roots, and gives directions for the digging and ripening of 20 or 25 tons weight. This letter is iu answer to one from Major Craig, of June 6, 1796, in which he had evidently made a proposition to Mr. Eichbaum to go to Pittsburgh, which the latter accepts conditionally if Messrs. Craig & O'Hara's resolve to build glass works is "absolutely fixed ". g Craig's History of Pittsburgh, pp. 276, 277. h Gallatin's works used wood, as did Denny & Beelen's, the third west of the mountains. i See Gallatin's Report on Manufactures in 1810. j The Glass House riffle works referred to below used wood, its location on the north bank of the Ohio rendering this necessary. k See Pittsburgh an It Is, by George H. Thurston, Pittsburgh, 1857 ; also Bishop's History of American Manufactures, which probably follows Thurston. Mr. Thurston's authority is a statement of the late Mr. William McCully, a well-known Pittsburgh glass manufacturer, who learned the trade of window-glass blowing in the Craig & O'Hara glass house. I think there can be no doubt but that Mr. Thurston either misunderstood Mr. McCully, or that Mr. McCnlly was mistaken. Mr. Mark Watson, Mr. McCnlly's son-in-law and his successor in business, authorizes the statement that in their many conversations on the subject Mr. McCully always spoke of the Craig-O'Hara house as the first. Mr. Isaac Craig also states that, as early as 1845, Mr. McCully told him that the Craig & O'Hara works was the first. 71 M M 84 MANUFACTURE OF GLASS. was in 1800 connected with this works. There seems to be no doubt that the Craig & O'Hara works was the first glass works not only in Pittsburgh, but west of the mountains, and was the pioneer of Pittsburgh's glass industry. The building erected was frame, and contained an eight-pot window-glass furnace using coal as fuel, three boxes being made at a blowing, the box at that time containing 100 square feet. What is now known as a box, 50 square feet, was formerly, even as late as 1860, termed "half box (H. B.)", and the rates of wages for blowing are still based on the box of 100 feet. Some idea of the pots in this pioneer factory can be obtained from the output. A box of 100 feet did not probably exceed 125 pounds in weight, which would give 375 pounds as the finished product of the blowing or of one blower at each melting, and allowing that the weight of product was four-fifths of the weight of batch, the amount of material charged into each pot would be but 500 pounds. Xow the weight of batch in each pot will average 1,500 pounds, and the average of a blower is nine to ten boxes of 100 feet. An old glass manufacturer expresses this difference in the size of the pots very graphically in saying : " One man could easily lift an old-style pot, now it takes four men." As was generally the custom in the window-glass houses of that day, one or more pots in the furnace were used for the manufacture of bottles "hollow ware," as they were termed. Among Colonel O'Hara's papers, found after his death, was a memorandum in his handwriting stating, " To-day we made the first bottle, at a cost of $30,000." (.) This remark has led to the belief that the works was a bottle house, but it was a window-glass factory, making some bottles. The partnership between Craig and O'Hara lasted for seven years, when Major Craig was persuaded by his relatives, who feared financial loss, to withdraw, (b) The works were continued by Colonel O'Hara. The difficulty and expense connected with this first attempt at glass-making west of the mountains were such as must have discouraged a less determined man than Major Craig, who seems to have had the immediate management of the works, he being in Pittsburgh most of the time, while Colonel O'Hara's other interests cal led him frequently from Pittsburgh. The men employed as superintendent and blowers did not always prove to be as highly skilled as their own assertions would have indicated, and many of the workmen seem to have been petulant, easily angered, and constantly threatened to leave the works. For some such reason as this, in December, 1798, the works were leased to Eichbaum, Wendt & Co., a firm composed of workmen who do not seem to have been very successful financially. Great trouble was experienced also in obtaining the proper materials. The cl&y which was found in the neighborhood, and which, as appears from a letter previously quoted, was supposed to be of the proper quality to make pots, proved unfit for use, and clay had to be brought from New Jersey in barrels over the mountains at great expense, and frequently the delays were so great that the furnace had to go out of blast for want of pots. When the clay came the whole force would be put to work making pots, which would be dried hurriedly, and the furnace would be put in blast again with the result that every glass-maker of to day would have anticipated the pots were lost. In one case, in an 8-pot furnace, three pots were lost at the first melting, and the next day four more, leaving but one in the furnace. Great trouble was also experienced in getting sand, and Major Craig's letters constantly refer to the different localities from which specimens were procured and the success in their use. The trials and the results obtained at this works are set forth in the following letter, dated August 5, 1803, written by Major Craig to Samuel Hodgson, of Philadelphia: With respect to our glass manufacturing, the establishment has been attended with greater expense than we had estimated. This has beon occasioned partly by very extensive buildings necessarily erected to accommodate a number of people employed in the manufacture, together with their families, and partly by the ignorance of some people in whose skill of that business we reposed too much confidence. Scarcity of some of the materials at the commencement of the manufacturing was also attended with considerable expense. We have, however, by perseverance and attention, brought the manufacture to comparative perfection. During the last blast, which commenced at the beginning of January and continued six months, we made on an average thirty boxes a week of excellent window-glass, beside bottles and other hollow ware to the amount of one-third of the value of the window-glass, 8 by 10 selliug at $13 50, 10 by 12 at $15, and other sizes in proportion. In the fall of 1800 the " commissioner of the city of Washington ", then just made the seat of government, applied to Craig & O'Hara to make for the public buildings some glass of larger sizes than had ever been produced in this country, but the attempt was unsuccessful. Glass of the size required, to the extent of some 400 square feet, was made "of a transparency tolerably good ", but it was too uneven for the purpose, or was spoiled in flattening, and the glass required was obtained from England. The second glass house built in the vicinity of Pittsburgh, and the third west of the mountains, was that of Denny & Beelen. This factory was situated on the north side of the Ohio river, in that part of Allegheny now known as Manchester, and gave the name to Glass-House riffle on the Ohio, (c) It used wood as fuel, its location being such that coal could not be procured without boating it across the river from the south side of the Monongahela, while wood was easily procurable. The exact date of the erection of this works has not been ascertained, though a Military Journal of Major Ebenezer Denny, p. 487. o Craig's History of Pittsburgh, p. 278. c Major Denny's Journal, p. 228. 1122 MANUFACTURE OF GLASS. 85 it was probably built in 1800. (a) Window-glass was made, whether crown or blown is not certain, though there is a legend that an attempt was made to manufacture the former. A Frenchman by the name of La Fleur, commonly known as " Falure", was brought to this country to have charge of the works; but they were unsuccessful from the first, and being compelled to cease operations after a short run, the furnace was abandoned, La Fleur entered the employ of Craig & O'Hara, and Beelen (b) gave up the glass business. As has already been stated, the manufacture of green-glass bottles, or "hollow ware", was carried on in these early glass houses in connection with that of window-glass, the "corner pots" in the window-glass furnaces being used for the manufacture of bottles and flasks. The history of the manufacture of bottles in the West is, therefore, for many years the history of the window-glass works. It was nearly forty years before furnaces for making bottles exclusively were built, and the records of the make of glass at Pittsburgh and of the works in that city as late as 1837 combine window-glass and green glass or bottles as one branch of manufacture. In 1837 there is a record of a "vial works" and a "black-bottle factory", (c) the latter "the only one of the kind in the western country ". This factory made wine, porter, and other black or amber bottles, as well as demijohns and carboys. The custom of using the " corner pot" for bottles is now entirely discontinued in this section, bottle manufacture being a distinct branch of the glass industry. The first attempt to manufacture flint-glass west of the Alleghenies was made in Craig & O'Hara's window- glass furnace in September or October, 1800, by Mr. William Price, of London, who had then lately arrived in this country, and who "had been employed altogether in flint-glass". September 5, 1800, Major Craig wrote Colonel O'Hara that Mr. Price had arrived, and had "offered to show us a specimen of his abilities without charge", and arrangements were made with Eichbaum, Wendt & Co., who were operating the works under lease, to allow him the use of a pot in the furnace and such assistance as he needed to make the experiment. On September 11, 1800, "one hundred pounds of pearlash, refined in the best manner, so that it may be perfectly pure, as it is to be applied in the composition of crystal glass by a man just from London", was ordered from Aaron Alma's, at Funk's tavern, on Franklin road. October 29, 1800, Major Craig sent a specimen of glass made by Mr. Price to Colonel O'Hara, and on November 17, 1800, in a letter to Colonel O'Hara, which he sent by Price, he wrote: " He [Price] has satisfied me, as well as others, that his ability in white-glass manufacturing is equal to his professions." These extracts from Major Craig's letters leave no doubt but that at this early date an attempt was made to produce flint-glass in Pittsburgh, and, further, that the advisability of building a furnace for its manufacture was seriously considered. Mr. Craig writes that he had hopes that some part of the window-glass house could have been used for the manufacture of flint-glass, but Price told him it could not be done. Major Craig seems to have had some doubt as to obtaining workmen and materials, and also as to whether the business would pay ; but Mr. Price was instructed to make an estimate of the articles needed and drafts of buildings, and submit them to Colonel O'Hara. No thing seems to have come from this attempt at the time. A careful examination of Mr. Craig's letter- books gives no evidence of the prosecution of flint-glass manufacture, and as late as 1803, as will be seen by the letter previously quoted, flint-glass was not made at these works. There is, however, a statement that should be quoted in this connection, to the effect that in 1802 Colonel O'Hara built an additional furnace at his works and attempted to establish the manufacture of white and flint glass, sending an agent to England to procure the necessary workmen ; but this agent is reported to have failed in his mission, (d) I have not been able to verify this statement, and a careful examination of Major Craig's letter- books of 1802 and 1803 gives no evidence of the existence of such a house, though they refer quite at length to Mr. Price's attempt at flint-glass making and to Mr. Edward Ensell, who afterward built a flint-glass works. Nor is any evidence of the existence of such a works found in Cramer's Almanacks. In the Altnanack for 1807 O'Hara's "glass factory" is mentioned, not his factories, as would have been the case were he making both flint- and window-glass, these requiring separate furnaces, (e) In the Almanack for 1808, which would give the establishments for 1807, the only glass works mentioned is "1 green-glass works". In the Almanack for 1809 Kobinson & Ensell's works appears for the first time, and is the only "white-glass" works, and the first one, mentioned. In Cramer's Almanack for 1804, among the amounts for each article made from raw material in Pittsburgh in 1803 are mentioned "jars, decanters, tumblers, blue glass". It has been argued that this proved the existence of a flint-glass house at Pittsburgh, as tumblers and decanters would hardly be made out of green glass ; but this supposition a The memoir prefixed to Major Denny's Journal, page P28, states that they were built " about the beginning of the present century''. In a letter from Major Craig to Colonel O'Hara, dated March 20, 1801, he writes, referring to this factory : "The Ohio glass works have stopped." These two statements would fix the date at least as early as 1800, and it seems from a number of letters that they were built in that year. 6 Beelen was a Belgian, son of the Austrian minister "Baron de Belen Bartholf ". Denny's Journal, p. 228. It thus appears that in the early glass works of Pittsburgh were represented the chief glass-making countries of Europe. c Lyford's Western Directory. These houses were on the south side, and have been known in recent years as " IhmsenV. d Thurston's Pittsburgh and Allegheny in the Centennial Year, p. 128; also, Bishop's History of American Manufactures, vol. ii, p. 96. e A flint-pot could not have been used successfully in the window-glass furnace, as pots for bottle-making were, the method of working precluding this. -, 86 MANUFACTURE OF GLASS. i is not borne out by the facts, as green-glass tumblers and decanters were quite common at that time, (a) In the Almanack for 1804 also appears the oft-quoted statement about glass-cutting " equal to any cut in the states of Europe" which was carried on at Pittsburgh, and it has been claimed that this indicated the presence of a flint-glass house. The amount reported cut, $500 a year, and the fact that the specimens of Mr. Eichbaum's skill at this early date seem to have been chandeliers, the beautiful clear glass of the prisms of which could hardly have been made in Pittsburgh, indicate that the glass came from east of the mountains, if not from Europe. The evidence I have found is against the existence of such a works, (ft) If such a factory as is mentioned ever existed, it must have been short-lived and of but little note, and cannot be regarded as marking the beginning of the flint-glass industry in Pittsburgh, which dates from 1808. In the fall of 1807 (c) Mr. George Robinson, a carpenter by trade, and Mr. Edward Ensell, an English glass-worker, who had been a manufacturer of both window- and flint-glass at Birmingham, England, and had sold his works and come u> this country to better his condition, commenced the erection of a flint-glass works at Pittsburgh, on the bank of the Monongahela, at the foot of Grant street, under the firm name of Eobinson & Ensell ; but the partners appear to have lacked capital and were unable to finish the works, and the establishment, in an incomplete state, was offered for sale, probably without having made any glass. In August, 1808, Mr. Thomas Bakewell and his friend, Mr. Page, who were visiting Pittsburgh at the time, were induced to purchase the works on the representation of Mr. Ensell that he thoroughly understood the business. This was the beginning of the firm of Bakewell & Page, that by itself and successors has continued the manufacture of flint-glass to the present, Bakewell, Pears & Co., their direct successors, reporting to the present census, (d) Mr. Bakewell soon found that the representations made to him as to the skill of the workmen he relied upon were not borne out, and he was forced to rely upon his own good judgment and his diligence in obtaining information about the business. The difficulties he met with would have disheartened a less determined man, and the lack of skill on the part of his workmen and the inferiority of the material interfered at first with his success. His furnace was badly constructed; his workmen were not highly skilled, and would not permit the introduction of apprentices, and his materials were procured from a distance at a time when transportation was difficult and expensive, pearlash and red lead coming from Philadelphia, and pot-clay from Burlington, New Jersey, all being transported over the mountains in wagons. The sand was obtained near Pittsburgh, but was yellowish, and up to this time had only been used for window- and bottle-glass ; the saltpeter from the caves of Kentucky until 1825, when the supply was obtained from Calcutta. These difficulties were in time overcome. Good clay was procured from Holland, and purer materials were discovered; and he rebuilt his furnaces on a better plan, competent workmen being either instructed or brought from Europe, and through his energy and perseverance the works became eminently successful. There can be no doubt that Mr. Bakewell is entitled to the honor of erecting and operating the first successful flint-glass house in the United States. The furnace built or completed in 1808 held six 20-inch pots. This was replaced in 1810 by a 10-pot furnace, (e) and in 1814 another furnace of the same capacity was added to the works. The establishment was burned down in the great fire of 1845, but was immediately rebuilt. The site is now occupied in part by the Baltimore and Ohio railroad depot, the brick part of the depot being a part of the old warehouse. The success of Messrs. Bakewell & Page induced others to embark in the business. In 1809 another flint- glass house was built, which produced glass on a limited scale, and in 1810 another company was formed, but failed in a short time. In 1812 another works, making the fourth in four years, was built. (/) It would thus appear that the manufacture of flint-glass increased much more rapidly than that of window-glass, as at that time there was in Pittsburgh only the O'Hara window-glass works, started in 1797. In 1810 the manufactures of the United States began to attract considerable attention, and for the first time the census returns include a statement of manufactured articles. In this year Mr. Albert Gallatin, then a These decanters were known as " big-bellied bottles", and were made out of the " corner pots" of the window-glass houses even later than 1837. Mr. Isaac Craig writes me: "I recollect distinctly seeing both tumblers and decanters made of green glass. In old times decanters were used in every house, most co.i.monly by the poorer families, who could not afford cut glass. Whisky was set out to every visitor in these decanters, and before and after every meal. Although of, green glass, they were not cut, but ornamented by beads around the neck." These beads were probably pin'ched on while the glass was still plastic. 6 The only evidence I have been able to find that this works ever existed is that contained in Thurston and Bishop. Mr. Thomas Bakewell, who came to Pittsburgh and entered into the glass business in 1808, and who was authority on the early history of glass-making in that city, seems to have had no knowledge of such a works, and speaks of Robinson & Ensell's attempt as the first. e Jarves, in his Reminiscences, who got his information from Mr. Thomas Bakewell, says 1808 ; but in Cuming's Tour, published in Pittsburgh in 1810, is a statement, p. 222, in regard to Pittsburgh, that "an account of the manufacturers and tradesmen was taken in the fall of 1807, the result of which was * * * a glass works for green glass on the opposite side of the Monongahela, another just erected for white glass on the town side of the same river". This latter undoubtedly was the Robinson & Ensell works. d Since the census year the firm has gone out of existence, after nearly three-quarters of a century of business life. e See Jarves- Reminiscences of Glass-making, to which I am indebted for many of the facts about Mr. Bakewell and his works. / Jarves' Reminiscences of Glass-making, p. 72. 1124 MANUFACTURE OF GLASS. 87 Secretary of the Treasury, made a report to the House of Representatives on our industries, in the course of which he mentioned that " two works, employing together six glass-blowers, had lately been erected at Pittsburgh, and made decanters, tumblers, and every other description of flint-glass of a superior quality". The Pittsburgh window- glass works is also mentioned, and it is stated that all of this kind of works in the country, with the exception of "that of Pittsburgh", used wood as fuel, the latter using coal. According to the census returns for 1810, there were three glass works in Pittsburgh that year which produced $62,000 in value. If Gallatin's statement is correct, two of these were flint works, and one manufactured window-glass and green bottles, (a) Concerning the condition of glass-making in Pittsburgh in 1813 and 1814 Cramer's Navigator (b) states: The manufacture of glass has succeeded as well as the most sanguine had expected. The situation of this place is particularly favorable, notwithstanding some disadvantages in procuring some of the materials. The first was established by Colonel O'Hara about the year 1798. (c) There are two glass works on the opposite side of the Monongahela, erected by Trevor & Ensell, and one in the new town of Birmingham, under the firm of Beltzhoover, Wendt & Co. These, with the three before erected, to wit, O'Hara's, Robinson's, and Bakewell's, will be able to manufacture to the amount of 160,000 annually. Both flint and green glass are now made here to great perfection. Messrs. Bakewell, Page & Bakewell have lately built another flint-glass works in addition to their former one. There are now in the town and opposite two whiti- and three green glass houses. Glass-cutting is likewise executed in this place not inferior to the best cut-glass in Europe. The furniture of the apothecaries' shops is altogether of home manufacture. This extract would indicate that some of the flint houses had gone out of existence and capital invested in glass-making was wisely turned to the branches that promised profit. The number of glass houses after this increased so rapidly that it is impossible to enter into the details of the history of each. In 1819, according to the memorial adopted at a town meeting and sent to Congress, the manufacture of glass in Pittsburgh had rapidly declined since 1815. At the latter date 169 workmen were employed, producing $235,000 in value of glass annually, while in 1819 the number had fallen to 40, producing but $35,100, and the statement is made that in flint-glass alone the reduction was $75,000. (d) In 1820 the census reports the product of " glassware and colored flint" as $20,000, and of " glass, window and hollow", as $24,000. In Fayette county, at the same time, there were three establishments making window-glass and hollow ware. In 1826 there were eight window-glass works in western Pennsylvania, producing 27,000 boxes (100 feet) of glass per annum, valued at $135,000, and, in additin, $30,000 worth of flint ware was made. In 1831 (e) there were four flint houses, with thirty-two pots, and four window-glass houses at Pittsburgh, four or five at Brownsville, one each at New Geneva, Bridgeport, New Albany, Perrypolis, and Williamsport, making window-glass, and one at the latter place making hollow ware. Mr. Bakewell at this time estimated that the value of glass produced in western Pennsylvania was more than $500,000 annually. In 1837 there were thirteen factories in Pittsburgh and its immediate vicinity, six flint and the balance window-glass or green hollow ware, making about $700,000 worth. Among these were the Sligo works of William McCully, established in 1828, and continued at the present day by W. McCully & Co.; the flint-glass works of Curling & Price, known as the Fort Pitt glass works, established in 1830, now carried on by their successors, E. D. Dithridge & Co. ; and the window-glass factory of F. Lorenz, now continued by Thomas Wightman & Co. Twenty years afterward, in 1857, there were thirty -three factories at Pittsburgh, of which nine produced flint-glass and twenty-four window, green, and black glass to the value of $2,631,990, employing 1,982 hands, whose wages were $910,116, consuming material to the amount of $2,078,734 40. In 1865 there were fifteen bottle and vial factories, fifteen window-glass factories, and fifteen flint-glass works in Pittsburgh, being forty-five glass houses in all; an increase of 36 per cent, in eight years. These fifteen window-glass works, located immediately at Pittsburgh, had a capacity to make 520,000 boxes of glass in a year, but their average yield was about 400,000 boxes, whose entire value at that time was $2,600,000. The fifteen green or vial works produced annually about 420,000 gross of vials and bottles, worth, at the, then rate, $2,100,000. The pressure upon these works at that time is best shown by the fact that, although only customary to run them for ten months in the year, yet many of them had run twenty-one months without stopping. The fifteen flint-glass works then in operation at Pittsburgh produced about 4,200 tons of glassware, worth then, in ro und numbers, $2,000,000. Their capacity was, however, double the amount produced, or about 8,000 tons. (/) a Cramer's Navigator, published in 1814, states that in 1810 there were two white and one green glass works in Pittsburgh. 6 The copy of Cramer's Navigator from which this statement is taken bears the date 1814, though the preface was written in 1811. The statement probably refers to 1813 or 1814, as the work was revised and published in several editions. c This should, of course, be 1797. d Address of the Philadelphia Society for the Promotion of National Industry, p. 257. e Report of the New York Tariff Convention, 1831, p. 121. / Pittsburgh and Allegheny in the Centennial Tear. By G. H. Thurston. 1125 MANUFACTURE OF GLASS. Below, I give in a tabulated form such statistical information as I have been able to gain as to the glass works of Pittsburgh from 1797 : Date. WINDOW AND BOTTLE. WINDOW. FLINT. GREEN BOTTLE. ALL KINDS. Works. Valne. Works. Valne. Works. Valne. Works. Value. Works. Value. 1797 1 1 $10,000 10,000 1 1 1 3 3 5 5 5 6 7 8 13 10 26 25 18 45 32 ||76 51 *$10,0 10,000 12,500 70,00* 62,000 170,000 286,000 240,000 35,100 235,000 500,000 728, 000 1800 Iflfll 1 1 $12,500 40,000 1810 2 $30,000 1812 1813 1815 1817 3 130,000 2 110,000 1819 1826 1 135, 000 100,000 1831 4 2 6 1837 5 2 1840 1850 11 7 5 16 8 9 7 9 1857 2,631,990 { 2, 075, 143 $6,700,000 J6, 832,42* I860 $875,520 2, 600, 000 1886 ... . 15 2,000,000 15 $2, 100, 000 1870 1876 24 12 41 30 11 9 1880 1,632,687 3, 215, 038 820,487 5, 668, 212 * Estimated. t 27,000 boxes made. ; From the census, and evidently incorrect. $ Evidently estimated. || Number of furnaces, not of works. At the present census, as will be seen by an examination of the tables, Allegheny county stands first as a glass-making center. Its statistics are as follows: I UMBER OF EMPLOY^! , 1 ! Kinds of glass. establish- ments. Capital. No. of furnaces. No. of pots. Total Males over 16. Females over 15. Children and youths. Total wages paid. Valne of ma- ; terials used. | j Total value of product. 12 $1, 880, 000 23 216 1,133 1,101 $809, 842 $576 638 $1,632 68" 30 2, 744, 500 51 496 4,069 2,691 129 1,249 1, 500, 833 1, 180, 861 3, 215, 03f 9 856, 500 11 85 851 650 12 189 375, 750 382, 169 820, 48' Total 51 5, 481, 000 86 797 6,053 4,442 141 1,470 2, 686, 425 2, 139, 658 5, 668, 215 It will thus be seen that this county had 24.17 per cent, of the total number of glass establishments of all kinds in the country, 27.62 per cent, of all the capital invested, and produced 26.79 per cent, in value of the products. It had 20.69 per cent of the number of window-glass establishments, but 37.96 per cent, of the capital invested in window glass, and produced 31 per cent, of the boxes of glass made, and 32 per cent, of value of product. In flint-glass and glassware Allegheny cotmty had 32.97 per cent, of the number of establishments, 37.04 per cent, of the capital invested, and produced 33.60 per cent, of the value of this kind of glass made. In green glass this county had 16 per cent, of the establishments, 17.50 per cent, of the capital invested, and made 14f per cent, of the green glass produced. Of the total of the entire country in the three classes named window, flint, and green Allegheny county had 24.88 or 25 per cent, of the establishments, 31.76 or 32 per cent, of the capital, and made in value 28 per cent, of all the product. It should be noted that these calculations do not include plate-glass, of which none is made in this county, . nor do they include the works in Fayette and Beaver counties, which have their offices in Pittsburgh. While the figures show that the proportion of the glass of the United States made in this county is not so great as has been supposed, it indicates that of all the great industries of the country it is the one that produces at Pittsburgh the largest proportion. GLASS-MAKING IN MASSACHUSETTS. The history of the beginning of the manufacture of glass in Massachusetts is involved in some doubt. Bishop, in his History of American Manufactures, states that the earliest works was built in a part of what is now the town of Quincy, but in this he is probably mistaken, as the Salem works were undoubtedly the first. He 1126 MANUFACTURE OF GLASS. 89 assigns no date to this Quincy works, but Appleton's Cyclopedia gives it as about 1750. This works was, like most of the other early ones in this country, built by Germans, (a) and its site is known to this day as Germantown. Only black bottles were made, some specimens of which still exist, which are of very poor metal and of rude make. The proprietors failed some years before the Revolution, and the house having burned down, it was never rebuilt, (b) The first glass house in Massachusetts, and the first to which a date can be assigned, was erected in Salem about 1639. In this year Ananias Concklin, Obadiah Holmes, and Lawrence Southwick received two acres of land each "adjoining to their houses", which was granted to them as " glass men ", for the purpose of promoting the manufacture of glass. The next year John Concklin, another "glass man", was allotted five acres more bordering the previous grants. In December, 1641, the general court, for the encouragement of the enterprise, authorized the town of Salem to lend the proprietors 30, which was to be deducted from the next town rate, and the glass men were to repay it, " if the work succeeded, when they were able." (c) The works having been neglected for three years, the Concklins, iu 1645, received permission from the court to form a new company to carry on the business, (d) Glass was for a considerable time afterward manufactured at that place, which is mentioned in the Colonial Records, in 1661, as the Glass House field. In this, and those which for many years succeeded, it is probable that nothing more was attempted than the manufacture of bottles and other coarse descriptions of glass, (e) Assuming the date assigned to this works, to be correct, it certainly displayed a great deal of enterprise in the infant colony to thus early undertake the manufacture of glass, and, though the products were coarse, they answered the purposes of the colonists. Window-glass could be imported from England of a much better quality than could be made, but bottles were so bulky and so liable to breakage that they could be made to advantage ir competition with the works of the mother country. The history of the glass works of Xew England is involved in doubt for some years after this, but it is probable that a works was built at Boston just prior to the Revolution, as Lord Sheffield, writing at the close of the war, says : "A considerable glass manufacture at Boston failed there several years ago." In December, 1752, the general court passed an act granting Isaac C. W;uslow and others the sole privilege of making glass in the province. It is probable that this works was established at Boston, and that it was this failure to which Lord Sheffield refers. However this may be, Boston again began the manufacture of glass shortly after the Revolution, and this time with great and long-continued success. This new enterprise, the Boston Crown Glass Company, which was the first really successful glass works in the country, was greatly encouraged by the very liberal action of the state. In July, 1 787, Messrs. Whalley, Hunuewell, and others received from the legislature a charter conferring upon them the exclusive right to manufacture glass in Massachusetts fr fifteen years, and a fine of 500 was attached to any infringement of this right. The capital stock was exempted from all taxes, and the workmen from all military duties. Jarves also states that to counteract the effect of the bounty paid by England on the exportation of glass from that kingdom the state paid the proprietors of this works a bounty on every table of glass made. A pyramidal factory of brick was erected on a large scale at the foot of Essex street; but being found ill-adapted tc the purpose, it was afterward taken down and a wooden one, lined with brick, differently constructed, was put up in its place, its dimensions being 100 feet in length by 60 in width. On account of difficulties in procuring workmen and other embarrassments operations were not fully commenced until November, 1792. (/) The corporation commenced with the manufacture of crown window-glass, which was of a quality equal or superior to any imported. Materials were found to be abundant, and some six years later they produced about 900 sheets per week, worth $1 75 per sheet, or $82,000 per annum, (g) This works was incorporated as the Boston Crown Glass Company in 1809. Regarding the success ot this company Mr. Jarves says : The state bounty had the effect to encourage the proprietors and sustain their efforts, so that by perseverance many difficulties were overcome and a well-earned reputatien supported for the strength and clearness of their glass ; a glass superior to the imported, and well known throughout the United States as " Boston window-glass ". This reputation they steadily sustained, until they made glass in their new works at South Boston in the year 1822. The early success of this works led to the establishment of others iu various parts of the country, and many of the workmen of the Essex-street house were enticed away by flattering offers. In 1811 the proprietors of the Essex-street works erected large and improved works on the shore at South Boston, and to supply the workmen enticed away, as also to meet the wants of their factory, an agent was sent to England to procure a set of glass- workers. By the time they reached this country the war with England broke out, and the enterprise was defeated; a It is an interesting fact that some or all of the workers in the first glass houses of Virginia, Itferyland, Pennsylvania, atid New Hampshire were Germans. 6 See Jarves' Reminiscences of Glass Making, p. 5". Also Mass. History Col., vol. iii, p. 276. c Felt's Annals of Salem. d Colonial Uncords, vol. i, 344; ii, 137. e See Bishop's History of American Manufactures, vol. i, pp. 233, 234. / Mr. Jarves says in 1803, upon the arrival of a German by the name of Lint (probably Lindt). g See Bishop's History of American Manufactures, vol. i, p. 241. 1127 90 MANUFACTURE OF GLASS. for it became difficult to procure fuel aud the various means for carrying on the Essex-street works. After the war operations were resumed and continued until 1826, .when from bad management the company failed. In 1802 glass works were established at Middlesex village, then in the town of Chelmsford, but now a part of Lowell, by Hunnewell & Gore, of Boston. Window-glass was the chief product, though some other glass was made. Allen's History of Chelmsford^ published in 1820, states: On the east bank of Middlesex canal, a distance of 200 rods from Merrimack river, a large building, 124 feet long and 62 feet wide, with ut-cessary appendages for manufacture of window-glass, was erected in 1802. Near it is a two-storied house, handsomely finished, designed for the residence of the overseer, and around it, at convenient distances, a number of smaller houses for the accommodation of the workmen aud their families. There are appertaining to this manufactory about 20 families, consisting of 40 men, 20 women, and 40 children 100 in all. It is now in a flourishing state. About 330,000 feet of window-glass are annually made, or 3,300 boxes of 100 feet each, which, at f 13 per box, will amount to $42,900. The situation is very favorable for transportation to Boston, and those raw materials from thence which it would be expensive to convey by land. A ready and cheap supply of wood is also easily obtained, of which it is estimated that about 2,000 cords are annually consumed in the manufactory and houses attached to it. The manufactory consists of two furnaces, three flattening ovens, two tempering ovens, six ovens for drying wood, cutting, mixing, and pot rooms, a kiln for burning brick, a mill-house, and sand-house. The proprietors failed about 1827 or x 1828; the works were also burned about this time. In 1828 a corporation was formed and the works rebuilt, but it is uncertain if glass was made before 1829. In 1839 the works were abandoned and moved to Suncook village, Pembroke, New Hampshire. The process of manufacture at this works is thus described : (a) The process was to mix Morris river (New Jersey 1 ) or Massabesic lake (New Hampshire) sand with lime, sal-soda, black and white salts, etc. ; no sand was ever procured for the purpose in this region. Ten large pots were heated from one furnace, each pot making about 500 surface feet of glass per "melt", and there were on an average about twenty-five "melts" per month, running nine months of the year. The glass was first blown in cylindrical shape, like a long piece of stove-pipe, then cut along one side lengthwise and flattened. Various other attempts have been made in eastern Massachusetts to establish the manufacture of window-glass, the details of which I have not been able to ascertain. In 1860 a iarge establishment, the Boston crystal glass works, was erected at South Boston for the manufacture of sheet window-glass. This was followed by several smaller ones, but they all failed to make glass at a profit, and were abandoned. As an illustration of the losses frequently met with in these manufacturing experiments, it may be stated that the plant of this Boston crystal glass works, which cost about $186,000, after lying idle for fifteen years, was sold in 1881 for $60,000 to the Wai worth Tube Manufacturing Company. All the window- glass works in this section have been abandoned, and in the census year the only one in operation in the state was in the western part, in Berkshire county. Through the kindness of Mr. A. T. Servin, of Lenox Furnace, who has been closely identified with the glass industry of that section, I am enabled to give some details of the attempts to establish its manufacture in western Massachusetts. In 1812 a window-glass factory was started at Cheshire, probably the first attempt at the manufacture of glass away from the seaboard, and about the same time another was built in the near town of Chester Factory. These were brought into existence by the war of 1812, and owing to the superior quality of the sand were located at this place. Both of these ran but a short time. In 1850-'51 a window-glass factory was started at Cheshire, ran about two years, and was changed to a plate-glass factory. It has since been used for window glass, but is now abandoned. In 1853 a factory was started at Berkshire. This is still in successful operation, and is the only works that made window-glass in New England in the census year. In 1853 another factory was started at Lenox Furnace, but this was changed to plate-glass ; and in 1869 still another works was built at this place, which ran for about two years, but is now abandoned. The beginning of the manufacture of flint-glass in Massachusetts was an outgrowth of the Essex-street factory. Among the workmen brought to this country to operate this works were a number who were not only skilled window-glass blowers, but were flint-glass workers as well. When the window-glass works were compelled to suspend operations in part, owing to the difficulty of procuring materials during the war of 1812, a number of blowers were thrown out of occupation. Among these was Mr. Thomas Caiues, who was still living when Mr. Jarves wrote his Reminiscences. Mr. Caines, who was not only a skilled blower, but an admirable manager, and was also well acquainted with the art of mixing glass and the proportions employed, prevailed upon the proprietors of the window-glass works to build a smalt six-pot flint furnace in a part of their unoccupied works at South Boston. This establishment found full employment during the war of 1812. It, however, was compelled to cease operations, and though several attempts were made to operate it between 1820 and 1840 they were unsuccessful. About the same time that this South Boston factory was built the Porcelain and Glass Manufacturing Company was incorporated and built a flint-glass house at East Cambridge. The furnace was a small six-pot one, and workmen were brought from abroad to work it; but it proved a failure. In 1815 some workmen left the South Boston factory, leased this furnace at East Cambridge, aud commenced the manufacture of flint-glass under the firm name of Emmet, Fisher & Flowers; but want of harmony among the members of the firm led to a dissolution, and in 1817 the Porcelain Company disposed of their works at auction. These were bought by the New a See Vox PonuU. Lowell, Massachusetts. 1128 MANUFACTURE OF GLASS. 91 England Glass Company, which was incorporated in 1817, and from these works has been produced glass the equal of that made in the best English flint houses. This works, when it first started, had a small six-pot furnace, each pot holding about 600 pounds of batch. Some forty hands were employed, and the yearly product was about $40,000. Bishop, in speaking of these works in 1818, which he calls " one of the most extensive flint-glass manufactories hi the country ", says : Two flint-glass furnaces and tweuty-ibur glass-cutting mills, operated by steam, and a red-lead furnace, capable of making two ton* of red lead per week, enabled them to produce every variety of fine, plain, mold, and the richest cut glass, as Grecian lamps, chandeliers for churches, vases, antique and transparent lamps, etc., for domestic supply and exportation to the West Indies and South America. Virginia coal. New Orleans lead, Delaware sand, and other native materials were used. The capital was about 80,000, and the annual product 05,000. in 1823 it is stated that 22,400 pounds of glass vessels per week were made, many of which are beautifully cut, and were sent into Boston and other places for sale. Writing of these works in 1865, Mr. Jarves states that five furnaces were run, averaging ten pots each, with a capacity of 2,000 pounds to each pot. Five hundred hands were employed, and the yearly product was $500,000. This works is still in existence, but is leased to Mr. W. L. Libby, who runs only a portion of it. Its reputation for the excellent quality of its glass is still very high. In 1825 ground was broken for a flint-glass works at Sandwich, and in three months they commenced blowing glass. These works also comiueuced in a small way with an eight-pot furnace, the weekly melts being some 7,000 pounds; but at the time Mr. Jarves wrote his Reminiscences the weekly melts had been increased to about 100,000 pounds, and the one furnace, with eight pots, to four with forty pots. In 1865 Mr. Jarves states that two flint-glass establishments were in operation in East Cambridge, three in South Boston, and one in Sandwich. At the present time there are six glassware establishments in Massachusetts, of which one was entirely idle and virtually out of existence and another idle in part. Some of the most interesting chapters in the history of glass in Massachusetts are those recording the successes and defeats connected with the manufacture of plate-glass. These are given in 4etail in that part of this chapter treating of plate-glass. Here it is only needful to say that these attempts began at Cheshire in 1852-1853. The works was changed from window-glass to plate-glass, run for about two months,andwas then moved to Brooklyn, New York. The second effort was at Lenox Furnace. These works, after passing the vicissitudes narrated elsewhere, are still iu existence. Though at one time Massachusetts was in the foremost rank of glass-producing states, the lack of fuel has caused it to fall in the rear as to amount of product. In some lines as to quality, however, it is still unsurpassed. I* GLASS-MAKING IN NEW HAMPSHIEE. Glass-making in New Hampshire dates from near the close of the revolutionary war. In May, 1780, Mr. Bobert Hewes, of Boston, began the erection of a glass works in the town of Temple, and in the autumn or early winter he started his fires. At this time glass was in good demand in the rebellious colonies. England, of course, prohibited all exportation t'roiu her ports, and the severity of the blockade prevented the glass of other countries from reaching this in any quantities. Indeed, the holds of the blockade runners would scarcely find space for glass, when powder and shot were more in demand. Mr. Hewes, who had been left by his father quite a fortune, determined to undertake the manufacture of glass. Having secured a number of German Hessians and Waldeckers, who were skilled glass- workers iu their own country and had formed part of the mercenaries sent to this country with the British army, and who had deserted from it, he started this Temple works ; but the building was hardly completed when it was burned down. This was a serious blow, but to prevent the abandonment of the enterprise the people of Temple came to Mr: Hewes' assistance, and the works were reconstructed. Then frost shattered the furnaces so that they would not stand the fire, and they gave way at the first melt, (a) To add to his difficulties as a result of these delays and loss his capital was seriously impaired and money was needed to continue the enterprise ; but the people of Temple had no money to lend, and did not choose to invest it if they had. Mr. Hewes petitioned aid from the state, asking " freedom from taxation on his buildings", exemption of taxes for his men, and the granting of a bounty upon the glass produced. January 2, 1781, the house of representatives of New Hampshire voted to receive and accept Mr. Hewes' petition, but postponed the paying of bounty till good window-glass could be successfully produced. The persistence of Mr. Hewes is best illustrated by the following petition made to the selectmen of Temple -in the winter of 1781, written from Boston: GENTLEMEN : After due respects, hoping these will find yourselves and families well, they arc to inform, that, being almost discouraged by the misfortunes I have met with & the little spirit of the People to encourage me, I am almost determined to drop all thoughts of proprriitinjr tlie Glass-Manufactory in Temple, for why should I strive, to introduce a Manufactory to benefit a people that has not spirit enough to subscribe a trifle to encourage it, when I have met with a misfortune for if the Business ever conies to perfection it will be a greater service to the country than it possibly can be to me, even if I make my fortune f But, Gentlemen, it teas not money only, that a These facts concerning Mr/Hewes' enterprise are condensed from a paper on " Glass-making in the Merriniack Basin", published in Contributions of Old Residents' Historical Association, Lowell, Massachusetts, vol. ii, No. 2. 92 MANUFACTURE OF GLASS. induced me, but it was because I was satisfied I could do it, & in so doing serve my country most essentially more especially your Town. You will do well, Gentlemen, to consider this is not a thing for a moment, but it is laying a foundation for the good of Posterity ; for certain I am if my Glass-works are brought to perfection, they will soon be as universal as the Iron works, or many others ; as I said to Esquire Blood the other day, " that the Glass-makers should be employed, if it were only to steal their art." I think the Town of Temple, as a Town, will be highly culpable if they let this matter slip without a struggle. But it is not for me to point out the advantage you are all sensible of. What I have to say is what will your Town do to encourage the matter? I shall have to send 60 miles for stones to build my melting furnace, which will take eight teams, & then all the other furnaces are to be rebuilt; but all this while, the Glass-makers and families are to be supported, which will be a costly affair. Your court will make a Lottery, I suppose, but that will be a thing of Time. Can I be credited for one or two Carcasses of Beef, till the Lottery is drawn, or what way can you think of to help me till the works are set a going? I should be glad to kuow your opinion of the matter as soon as possible, so that I may know what to determine. From Your Friend and Humble Servant, RQBERT ^^ P. S. Mr. Ashley will wait upon you with this and receive your answer, and transmit it to me as soon as possible. R. H. P. S. If I could be properly encouraged, I would come up in the Spring and work at it myself till it comes to perfection. MARCH 5, 1871. The Town voted to advance upon a loan to Mr. Hewes 3000, with good security, to be assessed in two months, and collected as soon as may be. On the same day, March 5, Mr. Hewes' agent at the glass house wrote to the selectmen " requesting provisions". March 11, Mr. Hewes writes to the selectmen from Boston, declining the loan of 3,000, if security is required, states he will not assume any further risk or responsibility ; that ten times that sum could be secured in .Boston if he wanted it, but that he had determined to recede immediately, and proposed to sell his interest in the works at a low price; had resolved to do nothing further except bring down the workmen, if nobody appears to purchase the houses and tools. March 24, in a letter from Boston, Mr. Hewes proposes to the selectmen that he be supplied money on a loan, on the strength of the lottery, for which he seems to have petitioned the general court of New Hampshire, and requests that his glass-blowers be furnished with supplies for subsistence. It was not till March 30, 1781, that the lottery act was passed, giving leave to raise 2,000, new emission, for the Temple glass works, and appointing three men to conduct the lottery and report their proceedings and account to the general court within one year. A fac-simile of the lottery tickets may be found on page 171 of the History of Temple. The tickets would not sell, and I have no statement what their prize was to be. I infer the great obstacle to the success of the lottery to have been want of faith in the glass works, and as a result Mr. Hewes abandoned the enterprise. The works made both window-glass and glassware, and some of its products, among them a glass plate, are preserved in Harvard University. There is no record of any further attempt to make glass in New Hampshire until 1814, when by an act of the legislature, passed on June 24 of that year, the New Hampshire glass factory was incorporated at Keene. This works made oiily cylinder window-glass, and the census of 1820 reports it as having a capital of $25,000, paying out $11,400 for materials, $10,000 for wages, $500 for contingent expenses, employing twenty men and five youths, and producing $30,000 worth of window-glass from 1,825 bushels of sand, 200 barrels of lime, 547 bushels of salt, and 36 tons of potash. In the hands of its original owner the enterprise was not successful, and passed under the control of other parties, who, in turn, disposed of it to others. From 1847 to 1851 the works were operated by J. D. Collony, when they were finally abandoned, no part of them remaining. In 1817 a factory was started in the same town (a) for the manufacture of "black and flint bottles" by Justin Perry. This was operated until 1848, when it ceased work, for the same reason that the window factory was abandoned the high price of fuel. In 1840 Mr. William Parker, who had been operating a window-glass works at Middlesex village, Massachusetts, then a part of Chelmsford, but since annexed to Lowell, removed it to Pembroke, New Hampshire, where he built a brick glass house for window-glass. The motive for moving the works from Chelmsford to Pembroke was the reduced cost of supporting the workmen, ease of obtaining cheap fuel, and close proximity to an abundant supply of sand at Massabesic pond, in Chester, now Manchester. These works were carried on from 1839 to 1850, but were by no means a success in their new location, the expected supply of suitable sand proving a delusion, that from Massabesic producing glass of so dark a color, by reason of iron, that it was unsalable, and sand from the Maurice river, New Jersey, was the only resort, with increased cost for transportation. The revision of the teriif in 1845 brought another disaster, the duty on imported glass being made so low that the country was supplied with European glass at less price than the cost of production here. In 1848 the manufacture of sheet window-glass was abandoned and that of crown glass undertaken, but with no success, and in 1850 its manufacture was abandoned. a This is the account I have received from Mr. William S. Briggs, of Keene. Bishop, in his History of American Manufacturer, published in 1868, vol. ii, p. 206, speaking of the year 1814, says: "A glass manufactory was this year incorporated in Keene, New Hampshire, where it is still (1868) a principal business." This is probably an c rror. 1130 MANUFACTURE OF GLASS 93 In March, 1866, a glass house for the manufacture of bottles was built at South Lyndeborough, New Hampshire. This works is still in existence. Its characteristics and product will be found in the tables of this report. GLASS-MAKING IN NEW YOEK. According to Bishop's History of American Manufactures, among the early settlers on Manhattan Island was a glass-maker, Jan Smeedes, who is supposed to have been among the first to receive an allotment of land on the present South William street, between Wall and Pearl. He probably carried on the business of glass-making on the east side of the street, just north of Hanover square. This street formerly bore within the above limits the name of " the Glass-maker's street", and afterward Smee street, from its original occupant. Of the history of his works no account has been found. In addition to this early works at the southern end of the island there seems to have been a glass house located between Eighth and Eleventh avenues and north of Thirty-fourth street, as on De Witt's farm map of New York about 1732 there is an estate called " the glass-house farm ". The first of these works must have been built early in the seventeenth century, at least during the Dutch occupation of the island, which ended in 1664. It would thus appear that New York, equally with Virginia, Pennsylvania, and Massachusetts, counted glass-making among its very earliest industries, dating not much after the first colonization. From this time for nearly a hundred years no records of the existence of any glass works have been found; but no doubt there were some factories in operation at various points and at various times in this state, as well as in other states, though glass-making flourished but poorly in these early times. In 1754 a glass works was erected by a Dutch gentleman by the name of Bamber in Brooklyn, probably the first in Kings county, which now ranks second as a glass-produciug center in the United States. The Historical Society of that city have in their cabinet a glass bottle having blown on it the name of Mr. Bamber and the date 1754, (a) "the first one," so the record reads, " manufactured at the glass works started in 1754 on the site of the present glass works on State street. This enterprise, we are informed, was brought to an untimely end for want of sand; that is, the right kind of sand." From this statement regarding the sand Mr. Jarves is led to believe that the bottle must have been of flint-glass, and the works a flint-glass works, as sand suitable for green or black glass abounds on the shore near its location. This, however, would not be conclusive evidence of the fact that they were flint works, as we have no doubt that in those days, as "at the present time, reasons which are not at all the correct ones were frequently given for the failure of manufacturing establishments. Governor Moore, in a letter to the Lords of Trade and Plantations, dated Fort George, New York, January 12, 1767, says : The Master of a Glass House, which was set up here a few years ago, now Bankrupt, assured me that his ruin was owing to no other t*tu.se than being deserted in this manner by his servants, which he had imported at great expence ; and that many others had suffered and been reduced as he was by the same kind of misfortune. (6) To what works Governor Moore referred does not appear. From this time until 1780 1 have not been able to find any other record, when, as the evils of large importations began to be seen and felt, and the advantage of establishing domestic industry became impressed upon the minds ef the inhabitants of this country, efforts were made in New York, as in the other colonies, to re-establish the manufacture of glass. In April, 1786, specimens of white glass made at the glass house- that had lately been erected in Albany were presented to the American Philosophical Society. Mr. Elkanah Watson, in his Reminiscences of Albany, published in 1788, mentions a visit to the new glass house, erected by John De Neufville at a place about eight miles from Albany. Mr. De Neufville, who was a Dutch gentleman, and had been active on behalf of the American colonies during the revolutionary war, having sacrificed in their behalf nearly the whole of a fortune of a half- million sterling, invested the small amount remaining in what Mr. Watson terms the " hopeless enterprise " of a glass house, (c) In January, 1785, Leonard De Neufville and his associates, the proprietors of a glass factory situated at Dowesborough, in the midst of a well-wooded pine forest, described as 10 miles from Albany, and which was probably the same works as that referred to by Mr. Watson in his memoirs, applied to the legislature for aid in their undertaking, urging as a reason for this assistance that 30,000 were sent abroad annually for glass, (d) They also stated that they were able to manufacture any size superior to English glass. This expression would lead to the belief that the works was a window-glass works. In 1793 the legislature of New York voted a loan of 3,000 for eight years to the proprietors, three years without interest and five years at 5 per cent; but by this time the works had passed out of the possession of the De Neufville family. In The Appolo, published at Boston, under date of September 28, 1792, appears the following regarding this works : We learn from Albany that the glass works erected several years ago within a few miles of that city, and which has been deserted ever since for want of cash, is now owned by Messrs. McCallen, McGregor & Co., who have completely repaired it, supplied it with every material, and are now manufacturing and advertising for sale window-glass of every dimension. They want a good flint-glass maker. A* this manufactory must be of great public utility, it is to be presumed they will receive the greatest encouragement from all (American) glass dealers, (e) a Stiles History of Brooklyn, vol. i, page 309. d See Munsell's Annali of Albany, vol. ii, p. 205. 6 New York Colonial Documents, vii, page 889. e Quoted from The Appolo, p. 416, by The Historical Magazine, 2d S., vii, p. 16. o See Munsell's AnnaU of Albany, vol. x, pp. 219,220. 1131 94 MANUFACTURE OF GLASS. The new proprietors, McCallen, McGregor & Co., offered in 1793 a reward of $50 for the discovery of a bank of sand suitable for their use situated within ten miles of their works. In 1796, for the purpose of consolidating and extending tbe operations, a village ten miles west of Albany was laid out and named Hamilton, in compliment to Alexander Hamilton, and in the spring of 1797 the Hamilton Manufacturing Company was chartered by the state, and the company and its workmen exempted from taxes for five years. This works was one of the most extensive glass works at that time in the United States. Beside other enterprises in other lines of industry, they had two glass houses, with three large furnaces, employing about thirteen glass-blowers, and making an average of 20,000 fewt of window-glass per month, beside bottles and flint-glass. It is stated that they substituted kelp for pearlash in the manufacture of glass. Their glass, however, was in good repute, and the business was actively carried on for some years. Munsell states that this works suspended in 1815 for want of fuel, (a) 4 The next factory of which I . have been able to find any record is the Eensselaer glass factory, which was incorporated by the legislature of the state March 21, 1806. In 1809 two more glass works the Madison and the Woodstock Glass Manufacturing Associations were also chartered, but I have not been able to find any details of either. In the census for 1810, however, four glass works are reported : one in Albany county, two in Rensselaer, and one in Ontario. These works made that year 3,805,000 square feet of glass, which was valued by the marshals at 16 cents per square foot. In 1810 or 1811, according to Mr. Jarves, a company was formed in Utica for the manufacture of window-glass, and quite a number of workmen from the Essex-street works (Boston, Massachusetts) were induced to leave their employment and break their indentures by the offer of increased wages, but while they were on their way to the New York house, and just before they reached the state line, they, with the agent of the Utica works, were arrested, brought back, and an expensive lawsuit resulted. Mr. Jarves states that the latter works were abandoned and never revived. In the private journal of De Witt Clinton for the year 1810, when, as one of the commissioners of the state of New York, he examined the country between the lakes and the waters of the Hudson, appear several references to the glass works of the state, and under date of Geneva, August 9, 1810, he writes : A glass manufactory is erecting abont two miles from the village. It was incorporated last winter, and a little village is already rising up around it. One week later he writes : We entered the town of Vernon, in which three glass houses are in contemplation ; one has been in operation some time. It is rather to be regretted that this business is overdone. Beside the glass introduced from Pittsburgh, and from a glass house iu Pennsylvania, on the borders of Orange county, and the glass imported from Europe, there are ten manufactories in the state already, or about to be established ; oue in Guilderland, Albany county, one in Eensselaer county, three in Vernon, Oueida county, one in Utica, Oneida county, one in Rome, Oneida county, one in Peterborough, Madison county, and one in Woodstock, Ulster county. In 1818 the manufacture of window-glass was begun at Sand Lake, in Eensselaer county, by Messrs. Crandall & Fox. This locality was selected on account of its abounding both in sand and in fuel, but a few years' trial convinced the proprietors that the place was ill-chosen, and the location was abandoned. (6) In 1845 Mr. Samuel H. Fox, a son of one of the proprietors of the Sand Lake works, built a factory at Durhamville, which was in existence in the census year. The Utica Observer, in an article published some months since, claimed for Mr. S. H. Fox, one of the proprietors of this works, and one of the oldest living glass-makers in the country, that he was the first in the country to introduce soda-ash into the manufacture of glass, as he was the first in the state to utilize coal in the furnaces and to introduce wheel ovens. From the census of 1820 it appears that there were two window-glass factories in Madison county of this state, each containing two furnaces, with ten pots each. In Oneida county there was one cylinder window-glass factory in operation, and one crown-glass factory idle. In Ulster county there were two window-glass factories, manufacturing 800,000 square feet a year ; but of these works I have not been able to find any further details. In 1820 some workmen left the New England glass works at Cambridgeport, Massachusetts, and built a factory in New York city, the business beiug conducted under the firm name of Fisher & Gillerland; but in 1823 the partnership was dissolved, and Mr. Gillerland built a works in Brooklyn. In 1823 there was a manufactory of glass globes at Albany "on a scale which promised to supply the United States with the article". At the tariff convention which was held in New York in 1831 three flint-glass factories, with twenty-two pots, were reported in existence in New York and vicinity, and two cylinder window-glass factories : one at Geneva, and the other at Hamilton ; but of these, except the fact of their existence, no details were given. In 1832 the Eedford Crown Glass Company was incorporated and began the manufacture of crown glass in Clinton county, making a very good quality until 1841, when it failed. In 1846 crown glass was again made at these works. Of the establishment and history of the later glass works no record at all has been procured. GLASS-MAKING IN CONNECTICUT. Information regarding the early history of glass-making in Connecticut is exceedingly meager. It appears, however, that in 1747 a patent was granted by the legislature to Thomas Darling for the exclusive privilege of making glass for twenty years. This act appears to have become void because of the patentee's failing to fulfill its a Sec Muiisell's Annals of Albany. b This is Mr. Jarves' statement of the close of the works. It would appear, however, from a newspaper paragraph regarding th Durhamville works, that the Sand Lake factory was in existence until 1852, when it was burned down. 1132 MANUFACTURE OF GLASS. 95 conditions, and at various times after this special grants were made to others to introduce its manufacture; but how successful these were I have not been able to find out. It seems that a few years after the organixarion of the Essex-street factory in Boston, which was built in 1787, a glass house was in operation in Hartford, Connecticut, and from a reference in Washington's diary (1789) it would appear that glass was made in. New Haven. In the census of 1820 two glass works are reported in existence in Hartford county, Connecticut, producing $27,360 worth of glass annually. Bottle-glass is also reported as made in Hartford county at the census of 1820 to the extent of $3,350 annually. At the tariff convention held in New York in 1831 a window- glass works is reported as in operation at Wellington. In the census of 1840 two establishments are reported in Tolland county, making $32,000 worth annually; one of these was probably the Wellington works. In 1850 but one establishment is reported; in 1860 two establishments in Windham county; and in 1870 three establishments. Of these works I have been able to get no information other than the fact of their existence. * At the census of 1880 but one establishment was in existence in the state, the flint-glass works at Meriden. GLASS-MAKING IN MARYLAND. On May 26, 1790, Mr. John Frederick Amelung presented a petition to the national House of Representatives, asking that the patronage of the government be extended to his glass manufactory at New Bremen, in Maryland. This is no doubt the works to which Mr. Carroll, of that state, alluded in his speech of April 17, 1789, when he moved that a duty be placed on window and other glass, with the exception of black quart bottles. Mr. Carroll's reason for his motion was that the manufacture of window-glass had been begun in Maryland, and had been attended with considerable success, and he believed that with small encouragement it would be permanently established. Mr. Carroll's motion was successful, and in the first tariff law passed under the present Constitution a duty of 10 per cent, ad valorem was levied on the kinds of glass mentioned. The patronage that Mr. Amelnng desired was a loan from Congress. The investigation and discussion that followed is memorable as raising, and for the time being deciding, the policy of Congress relative to bounties and protection. The committee to which was referred Mr. Amelung's petition for " patronage" reported June 30, 1790, authorizing the Secretary of the Treasury of the United States to make him a loan, not exceeding $8,000, Mr. Amelung giving satisfactory security for the reimbursement of the same within a certain number of years. In the debate which followed the presentation of this resolution a history of this gentleman's exertions in endeavoring to establish an American glass manufactory was given by Mr. Carroll. He commenced in 1775, brought into the country upward of 200 persons, mostly glass-workers, and had expended at that time over 20,000 in the undertaking. Owing to a variety of accidents, and particularly to the extraordinary rise in the price of grain, he now found himself " greatly embarrassed in prosecuting the business; but stated if he could be so far patronized by the government as to be favored with a loan of $15,000 or $20.000 it would afford him such relief as would enable him to surmount every difficulty". Congress, however, did not look upon this appeal favorably. Some of the members doubted the constitutional power of Congress to loan money in this way; others objected to it on account of the precedent it would establish, while others urged that the encouragement and assistance could be asked for with more propriety from the state government. Mr. Boudinot gave an account of the manufactory, and said : " I have seen the glass made in it, which is superior to any ever produced in America." He contended that Congress had a right by the Constitution to loan the money, and cited several instances in point. He enlarged on the merits of the petitioner "in embarking such large property to prosecute a business of so general utility", and pointed out the consequences which would result from a "failure of this application, which would be greatly injurious to the petitioner and to the public ". The report, however, was negatived, and the question between bounties and protection was virtually decided by this debate. In 1794 Mr. Amelung presented a petition for an increase of duties, and in this he was joined by others, among them Thomas Whalley and his associates, of Boston, Massachusetts. Mr. Amelung's works appears to have been originally built on Tuscarora creek, four miles above Fredericktown, and were known as the Etna glass works. Window-glass and wine bottles were made, and it is probable that some of the workmen from this factory were among those that crossed the mountain to New Geneva and aided Albert Gallatiu to establish their manufacture ou the Monongahela. The works of Amelung were moved to Baltimore "in 1788, and located on the south side of the basin", and an account of Baltimore, published some years since, declares " they still continue". InLossiug's Home of Washington (pages 204-205) is an extract from a letter of a gentleman of Cincinnati describing the presentation to Washington by Mr. Amelung of two flint goblets bearing the general's coat-of-arms. Amelung's ventures did not succeed, and it is possible that he crossed the mountains to Pittsburgh with some of his glass- workers, (a) In 1790, according to Howard, a factory known as the " Baltimore glass works" was established on Federal Hill. Colonel Scharf, in his Chronicles of Baltimore, page 236, makes the date 1799. This was the window-glass works at present operated by Baker Brothers & Co., and still known by the same name. This firm also have flint and green glass houses. Concerning the latter, they write me that it was originally established in 1790, though the present works date only from 1852 ; the fliijt works date from 1873. a Cnming-'s Journal, page 66, speaks of a Mr. Amelnng, a glass-worker, at Pittsburgh. 96 MANUFACTURE OF GLASS. The census of 1810 gives statements of three glass works in this state, two in Frederick county, at which 40,000 square feet of window-glass and 7,000 bottles were made, and one in Baltimore county, at which 500,000 square feet of window-glass were produced. The census of 1820 reports a glass works in Alleghany county, at which both window-glass and hollow ware were made, and gives the date of the establishment of the works as 1817. The value of the products is given as $30,000, thirty men and eight children and youths being employed. The same census gives statistics of a window- glass works in Baltimore county that had been in operation twenty years, and was producing 3,400 boxes annually, valued at from $8 to $10 a box. At the tariff convention held in New York in October, 1831, two flint-glass furnaces, with twelve pots, were reported in operation in Baltimore ; also one cylinder window-glass factory in Baltimore and one in Cumberland ; but no details are given of the same. The works other than the above at present in existence in Maryland are of comparatively recent date, and are all situated in Baltimore, with the exception of a glassware factory building at Cumberland. GLASS-MAKING IN NEW JEESEY. (a) The first glass factory in New Jersey was located about 2J miles from Allowaystown, Salem county, and was built some time from 1760 to 1765 by a German named Wistar, who brought a company of workmen with him from Germany. He carried on the works a few years, and failed about the outbreak of the revolutionary war, and upon his failure, in 1775, the workmen went to what is now known as Glassborough, Gloucester county. Two objects led to the selection of this place as a site for works : it was so far inland that the operations were not interfered with by the armies, and it was a yellow-pine country, which wood was better for melting glass than the oak of Allowaystown. Mr. Bodine is of the opinion that "the principal kind of glass made was hollow ware or bottles; but from some recollections of an old man that descended from and knew some of the old Glassborough settlers and heard them talk when he was a boy, I think part of them, if not all, could make both bottles and window-glass, such as was used in those days". The blowers at these works also made the pots, cut the glass into lights, and packed the same. In the scheme of division of labor in more modern works each of these operations is a separate branch of work. At this works the bottles were made without molds, and crown-glass was made. Mr. Bodine says : I knew some blowers, when I was a small boy, that were then old men, and could make both bottles and window-glass. I have been unable to fix a time when window-glass commenced to be made in cylinder form. I find that about 1812 or 1813 a crown-glass (window- lights) factory was started up the Delaware river, 10 miles from Belvidere, at a place called Columbia, in what was then Sussex county, . now being Warren county. This factory run until 1833, when it ceased operations. I personally know of cylinder window-glass being made in 1827 or 1828 at Millville. About the time of starting the Columbia works a factory was started at a place called Clemonton, now in Camden county, where bottles were made part of the time and window-glass the balance. My informant worked at Clemonton in 1814 as an apprentice, learning to blow. About the years 1814 and 1815 there were factories started at Port Elizabeth, Cumberland county, and at Malaga, Gloucester county. Both of these were run as window- glass factories, and in 1816 to 1819 Tuckahoe and Hammonton were started and manufactured principally window-glass. The next works was Millville, started in about 1822. For some years after this no new works were started, until 1827, when between that date and 1832 Waterford, Jackson, old Brooklyn, and Winston were built. These last-mentioned places were in what was Gloucester, now Camden county. The next location was Squankum, now Williamstown, built in 1835, making bottles; then Estilville, Bridgeton, and Temperanceville (now part of Glassborough), built in 1836 and 1837; then Jersey City flint-glass works, built in 1840 or 1845. Somewhere about this date there was a flint-glass works built at Kaigu's Point, now part of Camden. Then Greenbank, 1840 to 1845; New Columbia, 1845 to 1848 ; Jausboro', 1848 ; Balsto, about 1850 ; Crowleytown, 1850 to 1851 ; Clayton and New Brooklyn, about 1851 to 1852; Medford, Milford, and Lebanon, 1855 ; Bulltown, 1858; Quinton, 1858 to 1860; Salem, 1863; Westville, 1868; Eiverside and Herman City, about 1870. There was a glass works started at Elizabethport some twenty -five years ago and run for a short time ; also, one started in Camden about 1868, and run for a short time. This makes in all thirty-seven locations in New Jersey. Of these the following have gone out of existence entirply: Allowaystown, Columbia, Clementon, Tuckahoe, Hammonton, Jackson, Old Brooklyn, Estilville, Greenbank, New Columbia, Balsto, Crowleytown, Kaign's Point, Milltown, Bulltown, Lebanon, Westville, Jersey City, and Elizabethport nineteen in all; two run two years, one three years, two five years, two ten years, four fifteen years, four twenty years, two thirty years, one thirty-five years, one forty-five years, while Waterford, Medford, Camden, New Brooklyn, Eiverside, Herman City, and Port Elizabeth, seven in all, have not run for several years. The balance of the locations, eleven in all, have forty -five furnaces, of which thirty-nine furnaces have run the past year, to wit : twelve window-glass, twenty-one green hollow ware, and six lime or white glass. Four of the green hollow ware and the six lime or white glass furnaces are situated at Millville, and are run by one firm, Messrs. Whitall, Tatum & Co. a For most of the data contained in the very interesting account of glass-making in New Jersey I am indebted to Hon. John T Bodine, of Williamstown, New Jersey, whose personal recollections extend back fifty -three years. 1134 MANUFACTURE OF GLASS. 97 About four miles below Millville are located the largest beds of glass-house sand in the state, sand beiug dug for the Millville and the Philadelphia, New York, and Boston factories. The pits have been opened for more than fifty years. There are also large sand-beds near Williainstown that supply twelve factories a thousand tons each per year. There is sand in very many other localities in south Jersey, but there is none better than the Maurice river, Millville, or Williamstown sand. Up to 1855 care was taken to locate glass works upon or near to large tracts of woodlanu. About the year 1856 the factories in New Jersey commenced to use anthracite coal, and since that time the pots have been enlarged at various times until they are more than three times the size they were when wood was used for melting. Mr. Bodine says : The use of coal has made locations of glass factories at places other than upon water navigation in New Jersey very expensive, even with railroaas. The cost of freight in getting coal and materials to and manufactured products from the marketable points of Philadelphia and New York is about 9 to 10 per cent, of the gross receipts of manufactured goods, while the only offset thereto is about 2 per cent, in the cost of sand and wood for annealing the ware. Many of the New Jersey works have been located where wood could be used. If the locations were abandoned, aiid the works removed to the large consuming points, the whole plant, so far as the building is concerned, would be lost. I find twenty-six of the factories among the forty-five contained in the eleven locations upon water navigation, and but for the advantage of water transportation we should not have as many glass factories as we now have. GLASS-MAKING IN OHIO. The information regarding glass-making in this state is exceedingly meager. It does not appear among the manufactures of the state at the census of 1810. In 1811 John Mellish, in his Travels, suggests that a well- organized manufactory of glass bottles would succeed, intimating that no such works existed. An account of Cincinnati, of date of June, 1815, states that a manufactory of green and window-glass and hollow ware was about to go into operation, to be followed the ensuing summer by another for white flint. Palmer's Travels in 1817 speaks of two glass houses in operation. The census of 1820 enumerates " glass, window, and hollow ware, chemical and philosophical apparatus ", as among the manufactures of Hamilton county, the value of the product being $19,000, and the statement is made that the works are languishing, owing to the supply overrunning the demand. Glass, both cut, flint, and window, was also reported as made at this census in Muskingum county, (a) At the tariff convention held in New York in 1831 a window-glass works is reported at Zauesville aud another at Moscow, while at the censnts of 1840 none are reported. In 1850 Ohio is credited with six works ; in 18(50 with four, and in 1870 with nine, three of which are reported as plate, probably window-glass, and six as glassware. Of the history of these several establishments I have no details. GLASS-MAKING IN MISSOURI. (6) As early as 1842 efforts were made to establish the manufacture of glass at Saint Louis. In that year a company of gentlemen, with Mr. James B. Eads, who has since become known in connection with the magnificent Saint Louis bridge and the jetties at the mouth of the Mississippi river, established the works now known as the Saint Louis glass works. This works at first made flint-glass tumblers, etc., and it is stated that Mr. Eads, finding it impossible to get the proper workmen, himself made the pots used in this factory. Five years of toil and vexation was the only result, and he and his associates, finding success impossible, were forced to suspend payment and abandoned further effort. To the credit of Colonel Eads, it should be stated that in after years he paid up every dollar of indebtedness incurred. Thus the first glass-making venture west of the Mississippi river passed into history as a failure. The factory was changed to a green-bottle works by Mr. Eads' successors, and then in 1854 back to a flint works. In 1855-'56 a green-bottle house was added, and in 1861 Bayot & Cummingstook the works, since which it has been a flint house, now manufacturing only flint bottles. The second works, those of the Missouri Glass Company, began operations in 1851, making window-glass, but ceased after running two years, remaining idle until 1856, when they were purchased and changed to flint- glass; but after sinking considerable sums in fruitless efforts the parties owning them sold out and abandoned the field. These works, then, like the Saint Louis glass works, became the property of various persons, who at different times encountered unvarying failures, until at last, in 1865, operations were wholly abandoned and the building taken for the manufacture of agricultural machinery. The other Saint Louis glass works have all been established since 1870. GLASS-MAKING IN OTHER STATES. As to the history of glass in other states but little has been learned. Glass has been made in Vermont, but there is none made at present. Two glass-houses are reported in that state at the census of 1840, one in Addison and one in Chittenden county, but none are reported in 1850, 1860, or 1870, nor at the present census. In Ehode Island no/glass, as far as I have been able to learn, was ever made, and the same is true of Maine and Delaware. In the southern states, with the exception of Virginia, Kentucky, and possibly Tennessee, I can find no record of glass- making. . a I have seen a statement that this Zanesville works was the first in Ohio, but I have been unable to verify it. 6 For the facts in this sketch I am indebted chiefly to an article in the Saint Louis Trade Review and to Mr. J. K. Cummings, of Saint Louis. 1135 98 MANUFACTUEE OF GLASS. It has already been stated that the glass-blowers that Albert Gallatin induced to aid him in starting the Few Geneva works were on their way to establish a glass house near Louisville, Kentucky; but it seems to have been many years before any other glass-makers sought this state to practice their art. Cramer's Navigator for 1814 states that a glass house had lately been built at Louisville, but neither the census of 1820 nor that of 1880 gives any evidence of the existence of this factory. At that of 1840 one glass-cutting establishment is reported in Kentucky, but no glass works. In 1850 no glass works is reported, though the Covington flint-glass works was established in 1848. In 1860 statistics of one glassware establishment are given in Jefferson county, in which Louisville is situated, but no facts are given regarding Kenton county, in which Covington is located, though the Covington glass works inform me that their flint-house was established in 1848, and their green-glass house in 1860. In 1870 three works are reported. The statement is frequently made that the first glass works west of Cincinnati was built at Alton, Illinois, and in the returns received from the Alton factory the date of establishment of this works is given as 1867. No glass is reported as made in this state in any of the censuses until that of 1870. A similar statement can be made of Indiana. Michigan has no place in the several censuses as a manufacturer of glass. No glass is reported as made in Wisconsin at any census, though an establishment was started shortly after the close of the census year 1880. Mississippi was building a works during the census year. Glass-making was established in California in 1863. or at least a works was in operation, but of the details of its history I have no record. / HISTOEY OF THE MANUFACTURE OF PLATE-GLASS IN THE UNITED STATES, (a) It is probable that the first attempt to manufacture in this country what is now known as plate-glass was made at Cheshire, Massachusetts, though some rough cast plate may have been made earlier at some of the window- glass works. The extensive deposits at this place of exceedingly good sand, which was at one time supposed to be the only sand in the country from which good glass could be made, no doubt had much to do with this early attempt to make plate-glass and determined the location of the works. In 1850 a window-glass factory was erected at Cheshire, which was run for two years on blown glass. In 1852- ; 53 this. was changed to a rough cast-plate factory. A large amount of money was expended in fitting up the works and putting in the necessary machinery and tools, but it was operated only for about six months, when the tables, tools, fixtures, etc., were removed to Brooklyn, New York, and a factory was there fitted up and operated through 1854 and 1855. Very little glass of a merchantable quality was made, and in 1856 the works were abandoned, (6) one of the chief causes of the failure, no doubt, being the small scale on which the works were projected and operated and the inexperience of the promoters. The manufacture of plate-glass requires large capital and experience, and it was not until these were brought together that the plate-glass industry was firmly established in this country and the product could compete with the foreign. The second effort was made at Lenox Furnace, Massachusetts. In 1853 a glass works was erected at this place at a cost of $30,000 for making window-glass by the Lenox iron works, a corporation owned by William A. Phelps, Oliver Peck, and James Collins, who ran the works for about two years on window-glass at a loss. In the fall of 1855 the window-glass business was abandoned. This property was leased with contract to sell to James N-. Richmond, who organized a company called the National Plate Glass Company, and was converted into a plate-glass factory. The company spent a large amount of money in reorganizing the establishment and experimenting, having bought the tables and tools of the Brooklyn company. In 1856, after a heavy loss, the company failed, and in 1857 the property came back to the original owners, who started up the works and continued to run them with success till the spring of 1865. In 1862 the factory buildings, with a large amount of glass, were destroyed by fire. There was no insurance, and the loss was over $25,000. In 1865 a company was organized, called the Lenox Plate Glass Company, consisting of the old parties with Messrs. Theodore and James Eoosevelt, of New York city. Up to this time only rough plate was made, but it was the intention of this company to commence polishing as soon as suitable machinery could be obtained. It is worthy of notice that, although for a number of years plate-glass had been produced in England and in France, there had been scarcely any improvemeuts in the machinery used. Some few years previous to this parties in the western part of the state of New York had invented and patented a machine for grinding and polishing marble slabs, and this was found to work admirably in polishing glass ; but through the influence of Mr. John II. Plattc, then agent for the British Plate Glass Company of England, the owners of the patent were induced to put up one of these machines for the company, on condition that if the working was satisfactory they were to buy t^ie patent. The machine worked with satisfaction, doing its work in much less time than the old system. Mr. Serviii states that the company paid about $50,000 for the patent. The principle of this machine is now generally used, though with improvements, in a The statements of fact contained in this history are derived chiefly from letters from Mr. A. T. Servin, of Lenox, Massachusetts, Mr. E. Ford, of Jeffersonville, Indiana, and Mr. E. A. Hitchcock, of Saint Louis, and from Mr. W. C. De Pauw's testimony before the tariff commission. b This is Mr. Servin's statement. Mr. Ford, however, states that the first attempt was made at Williamsburg, New York, in 1850, on a small scale, for the manufacture of rough plate-glass only, but was abandoned. The next effort, he states, was by the same party at Green Point, New York, but this was also a failure. This, Mr. Ford states, was the parent of the Lenox works. 1136 MANUFACTURE OF GLASS. 99 polishing plate. About this time the Lenox Plate Glass Company was organized. The inventor having patented another machine in 1866 and 1867, this company bought the patents and put up some costly machinery, which was not completed till 1868 and 1869. About this time, and for two or three years previous, a company in Philadelphia held patents for making cryolite, a mineral from Greenland, into a material called cryolite or hot-cast porcelain, resembling white marble when worked, but having all the qualities of glass. This material was worked in the same way as glass. Through statements of great profits in this manufacture the Lenox company were induced to allow a new company to be formed January 1, 1870, called the Lenox Glass Company, which took all the property of the old company and gave the Philadelphia company $200,000 for their patents, also purchasing a large amount of cryolite from them. This new company expended a large amount in preparing for the cryolite manufacture, but after six or eight months working it was found to be a perfect failure, resulting in a total loss to the company of the cryolite and patents purchased, and in 1871 the company failed. The furnace has since been run on rough plate for a part of the time. In 1879 a large proportion of the glass property was sold at about one- thirtieth of its cost, and a new company has been formed, called the Lenox glass works. The next works built in the United States were at New Albany, Indiana, and it was here that polished plate- glass was first successfully and continuously manufactured. In the year 1869 Mr. J. B. Ford conceived the idea of erecting works for manufacturing polished plate-glass, and with this in view he visited Lenox, gathered what information he could on the subject from the workmen there who had been employed abroad, and returned to New Albany with a determination to make polished plate. He immediately entered into negotiations with manufacturers of plate glass machinery in Europe, and purchased one each of the best machines for grinding, smoothing, and polishing, and while wailing for their arrival, in company with his associates, built a works for rough plate. About the time the machinery arrived the works was burned, but a new one was built on a more extended scale. This new plant was measurably successful, but had to undergo the reverses that seems the fate of all plate-glass houses in this country. In 1872 Mr. Ford withdrew, since which time it has been run by Mr. W. C. De Pauw, who stated before the tariff' commission that until 1879 the works made no money, though the quality of the glass for some time had equaled the imported. In the same year that he withdrew Mr. Ford organized and built another works at Louisville. These he managed until 1875, when he left, there and organized a works at Jeffersonville, Indiana, the city having offered him some ground valued at $20,000. These works have been largely increased, make excellent plate, and were, with New Albany and Crystal City, Missouri, the works that made polished plate in the census year. Shortly after the organization of the New Albany plate-glass works Mr. E. B. Ward, of Detroit, and others, induced by the very extensive deposit of sand of an excellent quality at Crystal City, Missouri, organized the American Plate Glass Company, with a capital stock of $250,000, and began in 1872 the erection of works at the point named, this sum being increased in January, 1874, to $500,000. In 1875 the manufacture of plate-glass was begun, though with appliances much inferior to those now in use, and a considerable quantity of glass of good quality was produced. The usual difficulties, however, which attend new industries, by reason of lack of the requisite experience, were encountered. The production was irregular and uncertain as to quality, and in 1876 the work was suspended for several mouths, with a view to its resumption under more favorable conditions. In October, 1876, the enterprise was reorganized by the formation of a new corporation (the present Crystal Plate Glass Company), composed of most of the stockholders in the old company, in which additional capital was invested, and which acquired the entire premises, plant, and a large stock of materials on hand. Mr. E. A. Hitchcock, of Saint Louis, president of the old company, continued in charge ,s president. During the winter of 1876-'77 preparations were made for resuming work under such conditions as to profit by the experience already gained. 'Convinced by thorough examination of its superior advantages, a Siemens furnace was erected. These works have since been largely increased, and are producing plate-glass the equal of any made in the world. An extensive works for the manufacture of plate-glass is also being built at Hite's station, on the West Pennsylvania railroad, near Pittsburgh, by Mr. Ford, who built the works near Louisville, (a) Kegarding the manufacture of plate-glass in this country, Mr. W. C. De Panw, in his paper before the tariff commission, made some statements which he summarizes as follows : First. That all money put into plate-glass works in America prior to 1879 had been a total loss. Second. That some of the shrewdest, most energetic, and successful business men in Boston, New York, Philadelphia, Detroit, Chicago. Saint Louis, and Louisville had in the aggregate invested millions in plate-glass enterprises and lost the whole of it. Third. That no plate-glass had been made in America without loss to the maker prior to 1879. Fourth. That I, instead of having made a large fortune in a few years, as represented, have actually lost more than half a million dollars over and above all (very small) profit made since 1878. Fifth. That after a long, earnest struggle, I have succeeded in making good glazing glass at a small profit. Sixth. That Americans are paying about half as much for plate-glass to-day as they paid prior to the time plate-glass was made in tho United States at my works. IMPORTS OF GLASS INTO THE UNITED STATES. In order to show the amount of glass received into this country, I append a table giving the imports of glass into this country in the years 1876 to 1880, showing quantities and values so far as they are given iu the reports of the bureau of statistics, and also the value of each unit of quantity. a It is now (April, 1883) iu successful operation. 72 It M 1137 100 MANUFACTURE OF GLASS. TABLE SHOWING IMPORTS OF GLASS INTO THE 187(1. 18J7. Articles. Quantities. Value. Value per unit of quantity. Quantities. Value. Value per unit of quantity. $4 803 091 25 1 Bottles: 25, 306 44 2 125 84 Containing liquors . number.. 3, 740, 473. 74 3 313 957 73 3 Or jars filled with articles not otherwise provided for 6 970 00 1 748 00 Q Glassware : Porcelain, Bohemian cut, engraved, painted, colored, printed, stained, 567 269 17 496 705 62 7 silvered or gilded, not including plate-glass silvered, or looking- glasa plates. 60 833 97 54 319 15 Plate-glass, cast, polished, not silvered : 15 500 00 2 82 00 182 17 365 00 2 835 oo 163 8 117 75 3 615 00 101 949 00 67 008 00 657 ii Above 24 by 30 inches, and not above 24 by 60 do.... 442, 705. 50 1 024 318 33 340, 998 00 943 958 00 0.770 922 458,704.00 1 017 317 55 326, 150 00 0.711 857 Plate-glass, cast, polished, silvered, or looking-glass plate : 250 895 50 52 791 00 210 812 671 33 223 407 00 275 755 919 00 838 5D7 00 319 964 00 382 81 439 00 268 74 00 327 1(5 168 753 19 117 096 00 694 10 556 00 55 456 00 541 17 Above 24 by 60 inches - do. - 65 778 75 76 467 00 1 162 12 149 25 17 064 00 1 405 i ^ Plate-glass, rough, fluted, or rolled (excess of 1 pound per square foot in proportion) : 2 265 00 120 00 053 4 077 00 395 00 097 10 2 668 00 75 00 028 2 787 00 96 00 034 20 23 838 00 1 800 00 076 20 832.00 1 616 00 078 '1 870 783 50 33 741 00 039 258 708 00 13 261 00 051 >0 Window-glass, cylinder, crown, or common, unpolished: 6 330 449 00 215 619 88 0.034 4 677 14 00 154 815 00 033 in *M Above 10 by 15 inches, and not above 16 by 24 do... Above 16 by 24 inches and not above 24 by 30 do 7, 542, 537. 50 8 085 927 00 304, 205 46 376 706 34 0.040 047 5, 662, 851. 00 7 220 534 80 202, 878 00 288 382 47 0.036 0.040 ', Above 24 by 30 inches do 6 879 206. 00 425 486 00 0.062 7 378 928 00 381 517 00 0.052 "'1 "Window -glass, cylinder, aud crown, polished : 539 00 117 00 217 5 438 00 1 144 00 0.210 -'7 ?8 Above 10 by 15 inches, and not above 16 by 24 do Above 16 by 24 inches and not above 24 by 30 . do 1,244.00 72, 084. 75 477 00 8 391 00 0.383 0.116 6, 208. 00 15 662.00 1,704 00 5,288 00 0. 274 0.338 ") Above 24 by 30 inches and not above 24 by 60 . do 2, 316. 00 1, 221 00 0.527 2, 404. 00 1, 078 00 0.448 W "1 624 877 99 497 528 14 1138 MANUFACTURE OF GLASS. UNITED STATES IN THE YEARS 1876 TO 1880. 101 1SJ8. | 1879. 1SSO. Value Value Value Quantities. Value. per unit of Quantities. Value. per unit of Quantities. Value. per unit of quantity. quantity. quantity. $3 331 857 25 $3 281 420 09 $5 133,272 42 . . .. 2S 710 40 I 20,676 00 43,760 56 1 3 200 087 00 3 360 793 00 4, 276 410 (0 V 56,412 00 1 199 459 00 <) 7 271 00 11 049 00 7,391 00 4 428 00 1 607 00 2,668 00 i 458 44" 93 591 541 38 722,637 41 a . 29 965 00 41 Q5g go 38,381 36 7 10, 252. 00 1,858 00 0.181 14, 338. OH 2, 711 00 0.189 108,732.00 16,200 00 0.149 8 12, 601. 16 4. 413 00 0.350 27, 317. 80 8, 724 00 0.319 46, 185. 80 14, 721 00 9.319 9 58, 340. 50 33, 106 00 0.567 90, 434. 91 32,888 00 0.364 157, 804. 92 50,326 00 0.319 10 392, 594. 16 286, 537 00 0.729 562, 071. 08 240,480 00 0.428 719, 373. 06 285, 419 00 0.397 11 756, 779. 29 658, 560 00 0.870 869, 635. 12 421,401 00 0.485 874, 521. 64 390,741 00 0.447 12 121, 213. 00 18, 607 75 0.154 128, 904. 75 23,992 00 0.186 230, TiW. 42 50,823 00 0.220 13 619, 379. 50 133,430 00 0.215 697,652.50 165, 437 00 0.237 1, 000, 340. 42 269, 421 00 0.269 14 912,375.50 277, 113 00 0.304 1, 081, 357. 00 342, 750 00 0.317 1, 648, 187. 31 557,998 00 0.339 15 85, 545. 00 41, 865 00 0.489 102, 961. 00 45,460 00 0.442 153, 637. 00 75, 218 00 0.490 16 1,284.50 1, 251 00 0.974 1, 034. 66 1, 245 81 L204 6,020.66 4,274 73 0.710 17 80.00 5 00 0.063 18 2,441.00 163 00 0.067 405.00 29 00 0.072 10, 785. 00 196 00 0.018 19 3,585.00 153 00 0.043 7, 202. 00 365 00 0.051 X 957. 00 89 00 0.045 20 78, 588. 00 5,432 00 0.069 173, 384. 00 7.693 00 0.044 757. 90S. 00 25, 426 00 0.034 21 4, 330, 949. 00 124,033 91 0.029 3, 582, 364. 00 90,356 62 0.025 12, 041, 215. 00 308,978 11 0.026 22 5, 903, 795. 00 176, 184 84 0.030 5, 045, 243. 00 140, 367 05 0.028 11, 077, 758. 00 333,063 23 0.030 23 6, 576, 448. 00 226, 396 85 0.034 5, 836, 463. 00 184, 885 64 0.032 10, 693, 808. 25 351, 463 90 0.033 24 6, 242, 560. 50 274, 624 61 0.044 6, 225, 791. 83 237, 232 87 0.038 10, 137, 070. 00 412, 472 44 0.041 25 3,563.00 828 00 0.232 1, 675. 00 325 00 0.194 11, 900. 66 2,110 00 0.177 2A 8,724.00 2,601 00 0.298 15,460.50 3,256 00 0.211 28, 575. 58 4,153 00 0.156 27 10, 779. 00 4, 185 00 0.388 21, 031. 00 6,023 00 0.286 36, 938. 75 10, 605 00 0.287 28 1, 661. 00 690 00 0.415 4,039.00 1,690 00 0.418 12, 651. 66 4,229 00 0.334 29 30 538 896 96 680, 8C3 82 851,047 68 11 1139 INDEX TO OLA.SS Advantages of Siemens' gas furnaces - Aggry beads made in Phoenicia Agricola's time, furnaces in .- Air blast, cooling heated molds by Air bubbles in glass Air, effect of, on pots Albany, account of glass-making at ' Alexandria, Virginia, manufacture of glass at Alicaiit, Spanish soda of Alkalies and other materials used in glass-making Alkalies, the chief, used in glass-making Alkaline rocks in Germany, Friederich Siemens quoted on use of. Alkaline rocks in Germany, Julins Fahdt quoted on use of . . Alkaline rocks, use of, for bottle-glass Allegheny county, manufacture of glass in, in the census year Alumina in glass Amelung, John Frederick, petition of, for aid in glass-making Amelung, presentation of flint goblets by, to "Washington ... American fire-clay used American glass, quality of (note) American invention, pressed glass an American pot-clay, analyses of - American sand, Bontemps quoted on American sand, character of American sand, deposits of ' - American sand, mode of occurrence of. ....... ...... American sand, Mr. Henry Chance quoted on American sand, Thomas Webb & Son quoted on American stained glass (note) Ammonia process for making soda Amount of production of Roman glass Analyses of bottle-glass Analyses of English sand Analyses of flint-glass Analyses of foreign glass sands Analyses of French pot-clay Analyses of French sand Analyses of German pot-clay Analyses of glass sands of the United States Analyses of lead gluss Analyses of lime glass Analyses of plate-glass Analyses of sand not always indicative of quality Analyses of Scotch pot-clay Analyses of Stourbridge pot-clay Analyses of window-glass Analysis of American pot-clay Analysis of window-glass found at Pompeii Ancient Egyptian glass furnaces, remains of, found by Napo- leon I Ancient factories, location of, at months of rivers Ancient factories, sand used in Page. 36 60 34 49 44 43 93,94 78 31 30-34 30 28 28 28 88 34 95 95 18 69 58 40 26 28 28 25 26 26 69 31 62 23 26,27 23 29 40 27 40 30 23 23 23 25 40 40 23 40 56 CO 25 26 Pg. 59-64 30 59 30 58 56 31 56 51 46 4 4 4 45 56 19 18 25-34 52 20 22 61 59 75 44 44 44 44 l 75 75 75 70 74 Austria-Hungary, proportion of batch in glass houses of ..... 44 Austria-Hungary's specialty in glass-making ................ Austria-Hungary, statistics of glass manufacture in ......... 75 Austria-Hungary, working in glass houses of ............... 44 Austrian glass houses, sources of supply of sand for ---- ..... 28 Austrian glass pots, size of ................................. 41 Austrian sand, sources of supply of ......................... Austria, quartz still used in ................................ 28 Anstro-Hungarian glass houses, use of Siemens' tank furnaces in ....................................................... 44 Average daily earnings, fallacy of usual statements regarding B. Baccarat works, establishment of ........................... Bake-well, Mr. Thomas, and the manufacture of glass at Pitts- burgh ................................................... Balls, method of manufacture of, by pressing ............... Baltimore glass works, establishment of .................... Barbarians, influence of, upon glass-making ................ 1141 Ancient glass .............................................. Ancient glass a soda glass ........... . .......... . ........... Ancient glass, coloring matter of ........................... Ancient glass houses, sources of supply of soda for .......... Ancient pressed glass ....... . .............................. Ancients, extent of use of window-glass by the ............. Ancient soda impure. .................. . ........... . ....... Ancient window-glass, method of manufacture of.. ...... Annealing flint-glass ....................................... Annealing ovens for plate-glass, description of .............. Annealing vens in glassware factories, number of ...... . Annealing ovens in green-glass factories, number of ......... Annealing ovens in plate-glass factories, number of ......... Annealing plate -glass ...................................... Annual settlement of wages ................... - ............ Antiquity of window-glass, Winckelman's views on ..... .... Approximate composition of glass .......................... Arsenic used, amount of .................................... Arsenic, use of, in glass-making ............................ Artglass .................................................. Artificial glass, definition of (note) ......................... Art, uses of glass ........................................... Assyrian glass, character of ................. . .............. Aurelian, ordinance of, regarding tribute on glass ---- - ..... Austria, glass-spinning in ............................. ----- Austria-Hungary, cooling in glass houses of ................ Austria-Hungary, dimension of pots in glass houses of ...... Austria-Hungary, duration of heating in glass houses of ..... Austria-Hungary, duration of melting in glass houses of ---- Austria-Hungary, manufacture of glass flowers in ........... Austria-Hungary, manufacture of glass wearing fabrics in. .. Austria-Hungary, manufacture of plate-glass in. . ........... Austria-Hungary, number of plate-glass factories in ......... Austria-Hungary, present condition of manufacture of glass 66 86 48 95 65 104 INDEX TO GLASS. Barec of Bretagne Barilla, Spanish Barrels and casks used Basalt, decomposed, use of, for manufacturing (note) Bastie glass, method of manufacture of Batch, constituents of the Batch, definition of Batch, preliminary heating of Batch, proportion of, in glass houses of Austria-Hungary Battery jars, method of manufacture of, hy pressing Beads, manufacture of, in Virginia Beer-bottles, number made Beets and grapes, potash made from Belgian bottle-glass, constituents of Belgian glass, exportation of Belgian glass, quality of Belgian glass, statistics of manufacture of Belgian sand, sources of supply of Belgian window-glass Belgian window-glass, export of Belgian window-glass, importation of, into the United States. Belgium, production of plate-glass in Belgium's specialty in glass-making Bellaire, Ohio, glass-making at _ Beni-Hassan, figures on tombs at Beni-Hassan, glass-making figured on tombs at Benrath's definition of glass (note) Benzine, use of Blast-furnace slag, a glass (n ) Blast-farnaee slag, relative composition of, and glass Blast-furnaces, slag-glass from Blast, use of, in cooling Blister in glass, cause of Blowing and pressing united to produce same form of glass.. Blowing flint ware, description of process Blowing glass Blowing in molds, description of method Blown plate, definition of Blown plate, how made Blown window-glass, early manufacture of Blown window-glass, Theophilus' account of Bodiue, John T., on early glass-making in New Jersey Bohemian glass Bohemian glass, character of Bohemian glass, definition of Bohemian glass houses, time of melting in Bohemian glass pots, size of Bohemian glass, quality of Bohemian lime flint-glass, constituents of ., Boilers in glassware factories, number of Boilers in green-glass factories, number of Boilers in plate-glass factories, number of Boilers in window-glass factories, number of Bontemps quoted on American sand Boston, manufacture of crown-glass at Bottle-glass (note) Bottle-glass, analyses of Bottle-glass, Belgian, constituents of Bottle-glass, English, constituents of Bottle-glass, flint and, manufactured in Europe Bottle-glass, French, constituents of Bottle-glass, the term hollow-ware applied to Bottle-glass, materials used for, proportion of Bottle-glass, Pittsburgh, constituents of . Bottle-glass pots, size of Bottle-gJass, use of alkaline rocks for .. Bottles, manufacture of, in France Bottles, manufacture of, in window-glass houses Bottles, pressing Bridgeport, Ohio, glass-making at British exports of glass 114-J Page. 31 31 18 20 53 41 41 43 44 48 78 11 32 43 73 73 74 27 69 69 69 70 69 79 57 59 19 . 4 20 54 54 44 45 45 51 50 51 20 51 57 57 96 67 68 21 44 41 70,74 42 4 5 4 4 26 89 20 23 43 43 72 43 21 43 43 41 28 73 84 48 79 72 Pag.. British imports of glass 72 British islands, modern manufacture of glass in 68 Bubbles in glass 44 Building glass works, statistics of 3,13,14 Bulk, difference in, of melted and unmelted charge 43 Burgin furnaces, number of 4 Byzantine glass 62 Byzantine glass, character of 62 Byzantine glass, extent of its manufacture 62 C. Calcar arch 43 California, history of glass-making in 98 California, statistics of all works in, by counties 15 Capital invested in glass manufacture 3 Carbonate glass, color of 31 Carbon, use of, in glass 34 Carthaginian glass 01 Carts in glass factories, number of 4,5 Casks and barrels used 18 Castellani on Venetian glass manufacture 76 Casting and pressing, related processes 45 Casting plate-glass 45 Casting tables, description of 45 Casting tables in plate-glass factories, number of 4 Cast plate, composition of 19 Cathedral plate, establishments producing 3 Cause of the decline of the manufacture of glass in Rome.. .. 62 Causes of failure of early attempts to establish glass manu- facture 81 Cave 35 Censuses, previous, comparison with -2 Censuses, previous, omissions in 2 Chance, Mr. Henry, quoted on American sand 26 Chance's mixing machine 43 Character of ancient window-glass 56 Character of Egyptian glass 60 Character of French sand 27 Character of lead glass 21,33 Character of modern Spanish glass 07 Character of Phoenician glass 61 Character of Roman glass 62 Character of sulphate glass , 31 Chargers, mechanical 43 Charging 43 Cheapness of glass at Rome 62 Chemical glass 19 Chemical lime flint-glass, constituents of 42 Chemical classification of glass, difficulty of 19 Chemists' ware not included in report 1 Chief alkalies used in glass-making 30 Chief constituents of glass 19 Chief glass-making countries of Europe 69 Children in glass factories i 5 China, glass-making in 64 Christianity, influence of, on the manufacture of glass 63 Churches, use of window-glass in early 56 Church, influence of the, on glass-making 65 Classification, chemical, of glass, difficulty of 19 Classification, commercial, of glass, difficulty of 20 Classification, composition and properties of glass 19-23 Classification of glass 1,20 Classification of glass according to method of manufacture (note) 20 Classification of glass, Toinlinson's (note) 20 Classification of glass, Ure's (note) 20 Classification of Gobeleterie 21 Clay-grinding mills in glass factories, number of 4 Clear white lime flint-glass, constituents of 42 Clinton, De Witt, on glass-making in New York 94 Coal first used as a fuel in United States at Pittsburgh 83 INDEX TO GLASS. 105 Coal, mineral, first use of Coal, substitution of, for wood in glass-melting Coal used, amount of Coal, use of, in glass-making in 1810 Coke used, amount of Colbert and glass-making in France -- Cold stoking Colored glass, classification of, chemically Colored glass, definition of '. Colored glass pots, size of Coloring matter of ancient glass Color of carbonate glass Color of glass, effect of use of manganese on Color of sand not always indicative of quality Color of slag-glass Color of sulphate glass Commercial classification of glass, difficulty of Common flint, definition of Comparison with previous censuses Composition, approximate, of glass Composition, classification, and properties of glass Composition of cast plate Composition of enamel Composition of Egyptian glass Composition of glass, difficult to obtain Composition of green bottle-glass Composition of green glass Composition of lead flint Composition of lead glass Composition of lime flint .' Composition of window-glass Composition, variability of Condition of glass-making in 1608 Conductivity of glass . Connecticut, first glass house in Connecticut, history of glass-making in Connecticut, monopoly of glass-making in, granted Connecticut, statistics of all works, by counties Connecticut, statistics of glass-making in, at various dates. . Consolidated statistics of production, etc., of glassware Consolidated statistics of production, etc., of green glass Consolidated statistics of production, etc., of plate-glass Consolidated statistics of production, etc., of window-glass. Consolidated statistics of the materials used in the manufac- ture of glass Constituents of Belgian bottle-glass. Constituents of Bohemian lime flint-glass Constituents of chemical lime flint-glass Constituents of clear white liine flint-glass Constituents of English bottle-glass Constituents of English lead flint-glass Constituents of English plate-glass Constituents of English window-glass Constituents of French bottle-glass Constituents of French lead flint-glass Constituents of French lime flint-glass Constituents of French plate-glass Constituents of French window-glass Constituents of lead flint-glass Constituents of lime flint-glass Constituents of lime- white flint-glass Constituents of Pittsburgh bottle-glass Constituents of Pittsburgh lead flint-glass Constituents of Pittsburgh lime flint-glass Constituents of Pittsburgh window-glass Constituents of plate-glass Constituents of the batch Constituents of window-glass Constitutionality of loa.us of money to encourage manufac- tures discussed in Congress Construction of furnaces for different kinds of glass Page. 36 57 18 87 18 66 44 20 20 41 59 31 25 25 55 31 20 21 2 19 19,23 19 21 60 41 19 21 19 21 19 19 19 78 21 94 94,95 95 15 95 12 12 12' 12 18 43 42 42 42 43 42 42 42 43 42 42 42 42 42 42 42 43 42 42 42 42 41 42 95 35 Cooling in glass houses of Austria-Hungary ................. Cooling molds by air blast ................................. Cooling, time of . .......................................... Cooling, use of Wast in .................................... Cooper's mixer ............................................ Cost of making glass, items of .............................. Cost of Siemens'tempered glass ............................ Council of Ten, action of, on glass-making ................. Counties making glass, relative production of .............. Covered pots, time of melting in ........................... Covered pots, use of, in glass-making ...................... Craig & O'Hara asked to manufacture glass for public build- ings at Washington ...................................... Craig & O'Hara, glass manufacturers in Pittsburgh ......... Craig & O'Hara's glass works .............................. Cristaux same as lead flint ........................ . ........ Crown-glass, definition of .................................. Crown-glass making in New York in 1846 ................... Crown glass, manufacture of, at Boston .................... Crown-glass, method of manufacture../ .................... Crown-glass, time of melting, in English houses ............ Crown optical glass ........................................ Crushing strength of glass Crystal glass, definition of Gullet, proportion of ....................................... Curvette, use of, in plate-glass works Cutting flint-glass Cylinder glass, definition of Page. 44 49 44 44 43 x 54 65 11 44 57 84 83 82-84 21 20 94 89 20 44 21 21, 22 21 43 45 51 20 Dampness, effect of, on soda window-glass ............... ... 30 Decadence of Venetian glass-making ....................... 65 Decanters, early manufacture of, in Pittsburgh .............. 86 De Cesnola's discoveries of glass ............................ 61 Decline of the English glass industry ....................... 72 Decolorizer, manganese not a permanent ........ . ........... 33 Decolorizer, use of manganese as a .......................... 24 Definition of glass, Benrath's (note) ........................ 19 Definition of glass, Fownes' (note) .......................... 19 Definition of glass, Lardner*s (note) ......................... 19 Definition of glass, lire's (note) ............................. 19 Den ny & Beelen's glass house at Pittsburgh ................ 83, 84 Destruction of first glass house in Virginia .............. 78 Devitrification in its relation to manipulation of glass ...... 22 Difference in bulk of melted and nnmelted charge .......... 43 Difficulties attending the early manufacture of glass at Pitts- burgh ................................................... 84-86 Difficulties attending the early man nfacture of glass in Mary- land .................................................... 95 Difficulties attending the manufacture of glass in Virginia. . . 78 Difficulties attending the manufacture of plate-glass in the United States ............................................ 98 Difficulty of comparison with previous censuses ............ 2 Dimension of pots in glass houses of Austria-Hungary ...... 44 Direct-firing furnaces, number of. ................... . ...... 4 Directory of glass works .................. ............ .... ix Discovery of glass ......................................... 59 Discovery of soda-ash ..................................... 31 District of Columbia, statistics of works in ................ 15 Division of labor at early glass works ... ................... 34 Double glass, definition of ................................. 20 Double process, glass-making a ............................ 19 Draft animals used in glass works, number and kind of ..... 5 Drays in glass factories, number of ----- ................... 4,5 Drinking-glasses, Saxon ................................... 63 Druids' beads .............................................. 64 Drying of pots ............................................ 41 Duties on imports of glass, early action of Congress in levy- iug ..................................................... 9f Ductility of glass ......................................... 22 Dyottville glass works ..................................... 81 . ~i 1143 106 INDEX TO GLASS. E. Page. Earliest date assigned to the manufacture of Egyptian glass. 59 Early action of Congress levying duties on imports of glass . . 95 Early attempts at the use of salt-cake 31 Early attempts to establish glass manufacture 81 Early attempts to make plate-glass ia the United States .... 98 Early French glass works 63 Early furnaces 34 Early glass furnaces, description of 90 Early glass-making in the British islands 64 Early glass-making near Philadelphia 80 Early glass, variety of 34 Early glass works, division of labor at 34 Early glass works in Gaul 63 Early glass works in Spain 63 Early manufacture of decanters in Pittsburgh 86 Early manufacture of glass i n Pittsburgh 84 Early manufacture of mirrors in Germany 63 Early manufacture of window-glass in Germany 63 Early specimens of German glass 67 Early times in France, use of window-glass in 56 Early use of flint in glass-making 26 Early use of quartz in glass-making 26 Early Venetian glass-making 65 Early window-glass works in England 56 Earnings, average daily, elements necessary to ascertain 6 Economy of Siemens' tank furnace 38 Effect of air on pots 43 Effect of lead in the manufacture of glass 33 Effect of lime on glass 32 Effect of pressing in cheapening glass 58 Egypt, glass-making in, after the Christian era 59 Egypt, glass-making materials in 60 Egyptian furnaces, early .34 Egyptian glass 59 Egyptian glass, character and composition of 60 Egyptian glass, earliest date assigned to the manufacture of. . 59 Egyptian glass furnaces, ancient, remains of, found by Napo- leon 1 60 Egyptian glass-making, process of 60 Egyptian glass, varieties of 60 Egyptian soda, where procured 30 Egypt, natron lakes of 30 Egypt, state of the art in ancient 59 Eichbaum, P. W., glass-worker 81-83 Employe's, number of 6 Enamel, composition of 21 England, early window-glass works in '. 56 England, number of plate-glass factories in 70 England's specialties in glass-making 69 English art glass 1 69 English bottle-glass, constituents of 43 English fire-clay used, amount of 18 English flint-glass 69 English glass houses, sources of supply of sand for 27 English glass houses, time of fining in 44 English glass houses, time of melting in 44 English glass industry, decline of 72 English houses, time of melting flint-glass in 44 English lead flint-glass, constituents of 42 English plate-glass, constituents of 42 English sand, analyses of 26, 27 English sand, sources of supply of 26 English window-glass, constituents of 42 Engraving flint-glass 51 Essex-street glass works 89 Establishments in which glass was made in the census year. 3 Etching flint-glass 51 Etching, invention of 67 Etruscan glass 61 Europe, chief glass-making countries of 69 Europe, number of plate-glass factories in 70 1144 Paga Europe, present condition of glass-making in 69-77 Europe, production of plate-glass in 71 Excellence of Phoenician glass 60 Exportation of Belgian glass 73,74 Export, first United States, of glass 77 Export of Belgian window-glass 69 Exports of glass, British 73 F. Factories, plant of 4 Fahdt, Julius, quoted on use of alkaline rocks in Germany.. 28 Failure of early attempts to establish glass manufacture, . causes of gl Falls of the Schnylkill, glass works at the 81 Faults in glass 44,45 Fining ; 43,44 Fining, duration 'of, in glass houses of Austria-Hungary 44 Fining, effect of too long continued 43 Fining, heat of 43 Fining, time of, in English houses 44 Fining, time of, in lime glass houses 44 Fining, time of, in the glass houses of the United States 44 Fire-clay, American, used, amount of 18 Fire-clay, English, used, amount of 18 Fire-clay, German, used, amount of 18 Fire polishing 49 First export of glass from the United States 77 First glass house in New York 93 First glass house in Pittsburgh 83 First glass house in the United States 77 First glass made in the United States 77 First glass works in Connecticut 94 First glass works in Massachusetts 89 First glass works in Missouri 97 First glass works in New Hampshire 91 First glass works in New Jersey 96 First glass works in Pennsylvania 79 First glass works in Philadelphia, Pennsylvania 80 First glass works west of the Allegheny mountains 82 First mention of glass in Rome 62 First pressed glass 58 First pressed tumbler 58 First Roman glass works 62 Flashed glass, definition of 20 Flattening-ovens in window-glass factories, number of 4 Flattening window-glass, description of process of 50 Flint still used in Germany 27 Flint- and bottle-glass manufacture in Europe 72 Flint, common, definition of 21 Flint, early use of, in glass-making 26 Flint, German, definition of 21 Flint-glass, analyses of 23 Flint-glass, annealing 51 Flint-glass, Bohemian lime, constituents of 42 Flint-glass, chemical lime, constituents of 42 Flint-glass, clear white lime, constituents of 42 Flint-glass, cutting 51 Flint-glass, definition of 20 Flint-glass, English lead, constituents of 42 Flint-glass, engraving 51 Flint-glass, etching , 51 Flint-glass, first attempt at the manufacture of, west of the Allegheny mountains 85 Flint-glass, French lead, constituents of 42 Flint-glass, French lime, constituents of 42 Flint-glass houses, time of melting in 44 Flint-glass, lead, constituents of 42 Flint-glass, lead, proportion of materials used in the manu- facture of 42 Flint-glass, lime, proportion of materials used in the manu- facture of . . 42 INDEX TO GLASS. 107 Page. Flint-glass, lime, constituents of - 42 Flint-glass, lime-white, constituents of 42 Flint-glass making, early in Massachusetts, account of 89,90 Flint-glass, manufacture of, in Philadelphia, Pennsylvania.. 82 Flint-glass, permanent establishment of the manufacture of, at Pittsburgh 86 Flint-glass, Pittsburgh lead, constituents of 42 Flint-glass, Pittsburgh lime, constituents of 42 Flint-glass pots, size of 41 Flint-glass, tools used in the manufacture of 51 Flint, use of, in manufacture of glass 24 Flowers, glass, manufacture of, in Austria-Hungary 75 Foreign glass sands, analyses of 29 Form of furnaces, object aimed at in the 35 Fowne's definition of glass (note) 19 Franco, Colbert and glass-making in 66 France, glass of 63 France, manufacture of bottles in 73 France, manufacture of lead flint-glass in 66 France, manufacture of mirrors in 73 France, manufacture of plate-glass in 73 France, modern glass-making in 66 France, number of plate-glass factories in 70 France, plate-glass making in 66,73 France, quartz still used in France's specialties in glass making France, use of window-glass in early times in French bottle-glass, constituents of French glass houses, time of melting in French glassware, taste displayed in the manufacture of French glass works, early French lead flint-glass, constituents of French lime flint-glass, constituents of French plate-glass, character of French plate-glass, constituents of French pot-clay, analyses of French sand, analyses of French sand, character of French sands, mode of occurrence of 27 69 56 43 44 73 63 42 42 69 42 40 27 27 25 French' stained glass 69 French white glass, character of 69 French window-glass, constituents of 42 Frequency of payment 8 Fritting 43 Fritting furnaces 34 Fruit jars, number made 11 Fuel, coal first used as a, in United States at Pittsburgh 83 Fuel, economy of, in Siemens' gas furnace 36 Fuel used in early glass houses 36 Fuel used in Germany 74 Fuel used in glass-making 4 Furnaces 34-41 Furnaces, building, 1, 3, 13, 14 Furnaces, construction of, for different kinds of glass 35 Furnaces, description of early glass 90 Furnaces, early 34 Furnaces idle during census year 1, 2, 3, 13, 14 Furnaces, number of Furnaces, size of Furnaces used in Germany Fusion, effect of too long continued Fusion, heat of Fusion, time of o. Gallatin's glass works Gal latin's return ou the manufacture of glass in the United States (.ias bubbles iu glass Gas furnaces Gas furnaces at Wheeling 3 36 74 43 43 43 82 87 44 36 79 Gas furnaces, number of Gas furnaces, time of melting in Gaul, early glass works in v German fire-clay used, amount of German flint, definition of Geman glass, early specimens of German glass houses, location of - German glass pots, size of German glass- workers in the United States, early German pot-clay, analyses of ... ^ German sand, sources of supply of German silvered plate, importation of, into the United States. Germany, early manufacture of mirrors in Germany, early manufacture of window-glass in Germany, flint, still used in Germany, furnaces used in Germany, influence of, on French glass-making Germany, influence of Rome on glass manufacture in Germany, manufacture of mirrors in Germany, number of plate-glass factories in Germany, present condition of manufacture of glass in Germany, production of mirrors in Germany, quartz still used in Germany, statistics of manufacture of glass in Germany's specialty in glass-making Gill furnace, description of Gill furnaces, number of Glass, a fused mixture of two or more silicates Glass and metallurgical slags Glass-bead manufacture in Venice Glass-blowing, early, description of Glass-blowing figured on tombs at Beni-Hassan Glass, chemical Glass, chief constituents of Glass, classification of Glass, definition of, Benrath's (note) Glass, definition of, Fownes' (note) : Glass, definition of, Lardner's (note) Glass, definition of, Ure's (note) Glass, difficulty of chemical definition of Glass found at Poitiers Glass-gall Glass-gall, or sandiver Glass, how used commercially - Glass in France Glass, in the dark ages Glass, its composition, classification, and properties Glass-makers, special privileges given to Glass-making a double process Glass-making at Bellaire.Ohio Glass-making at Jamestown, Virginia - Glass-making at Keene, New Hampshire Glass-making at Martin's Ferry, Ohio Glass-making at Newcastle-on-Tyne Glass-making at Pembroke, New Hampshire - Glass-making at Wheeling, West Virginia, history of Glass-making figured on tombs at Beni-Hassan Glass-making, history of some processes of Glass-making iu Bridgeport, Ohio Glass-making in California, history of . Glass-making in China Glass-making in Connecticut, history of Glass-making iu Egypt, after the Christian era Glass-making in Germany Glass-making in Illinois, history of Glass-making in India Glass-making in Ireland Glass-making in Kentucky, history of Glass-making in Maryland, history of , Glass-making in Maryland in 1810 Glass-making in Maryland in 1820 1145 Page. 4 44 63 18 21 67 74 41 91 40 27 70 63 63 27 74 66 63 74 70 74 70 27 74 70 37 4 19 59 70 57 57 19 19 1,20 19 19 19 19 19 63 30 43 19 63 66 19-23 63 19 79 77 92 79 64 92 78 59 56,58 79 98 64 94,95 59 63 98 64 64 98 . 95,96 96 96 108 INDEX TO GLASS. Page. Glass-making in Mai yland in 1831 96 Glass-making in Massachusetts, history of 88-91 Glass-making ia Massachusetts in 1818 90 Glass-making in Massachusetts in 1823 90 Glass-making in Missouri, history of 97 Glass-making in New Hampshire, history of 91-93 Glass-making in New Hampshire in 1820 92 Glass-making in New Jersey, history of 96 Glass-making in New York, history of 93, 94 Glass-making in New York in 1820 94 Glass-making in New York in 1831 94 Glass-making in Normandy 63 Glass-making in Ohio, history of , 97 Glass-making in Ohio in 1820 97 Glass-makiug in Ohio in 1831 97 Glass-making in Ohio in 1840 97 Glass-making in Ohio in 1850 97 Glass-making in Ohio in 1860 97 Glass- making in Ohio in 1870 97 Glass-making in Pennsylvania, history of 79-88 Glass-making in Persia 64 Glass-making in Rome after the Christian era 62 Glass-making in Scotland 64 Glass-making in Spain 63 Glass-making in Virginia, history of 77-79 Glass-making in Virginia in 1831 78 Glass-making in Vermont, history of 97 Glass-making in Western Massachusetts, history of 90 Glass-making in West Virginia in 1840 Glass-making materials in Egypt Glass-making, profit in, no attempt to show Glass manufacture in France, present state of Glass manufacture in Germany Glass-melting, substitution of coal for wood in Glass-pressing, application of compressed air to Glass-pressing, application of steam to. Glass-pressing, London Pottery Gazette on the invention of .. . Glass-pressing, Pellatt an the invention of Glass- refining in Austria Glass sand in New Jersey Glass-spinning in Austria Glassware, capital invested in Glassware, consolidated statistics of production, etc Glassware factories, definition of Glassware, French, taste displayed in the manufacture of . . . Glassware, number of pieces made not reported on Glassware, product of, value of Glassware, relative productive rank of the states in Glassware works, furnaces in, number of Glassware works, pots in, number of. 78 60 ix. 73 67 57 49 49 58 58 44 97 75 3 12 1 73 10 9 9 3 3 Glass working, methods of 45-55 92 82 82 82 82 82 4 4 21 32 72 72 56 61 61 11 19 3 21 12 Glass works in New Hampshire in 1820 Glass works in Pennsylvania in 1810 Glass works in Pennsylvania in 1820 Glass works in Pennsylvania in 1831 Glass works in Pennsylvania in 1840 Glass works in western Pennsylvania, early history of Glory-holes in glassware factories, number of Glory-holes in green-glass factories, number of Gobeletei-ie, classification of Grapes, beets and, potash made from Great Britain, localities of the manufacture of glass in Great Britain, statistics of the manufacture of glass in Great Britain, window-glass used in, in the Roman period .. Greek glass Greek glass, earliest reference to Green and black bottles, number of Green bottle-glass, composition of Green glass, capital invested in Green glass, composition of Green glass, consolidated statistics of production, etc 1146 Green glass, definition of Green-glass factories, definition of Green-glass houses, time of melting in Green glass, production of Green glass, relative productive rank of the states in Green-glass works, furnaces in, number of Green-glass works, pots in, number of Grinding- and engraving-machines in glass factories, number of Grinding plate-glass, description of machinery for Grinding plate-glass, description of process Grinding sand used Ground glass, definition of Guinaud's method of making optical glass Page. 21 1 44 11 9 3 3 4,5 46 46 18 21 46 24 18 44 4:.! 35 43 28 II. Hardened glass Hardened glass, definition of Hardness of glass, on what it depends Hay and straw used, amount of Heating in glass houses of Austria-Hungary, duration of Heating of batch, preliminary - Heat of furnaces (note) Heiss-schiiren, heat of Herzogenrath (German) sand Hewes, Robert, attempts to establish glass-making in New Hampshire 91 History of glass-making in California 98 History of glass-making in Connecticut 94,95 History of glass-making in Illinois 96 History of glass-making in Kentucky 98 History of glass-making in Maryland 95, 9(1 History of glass-making in Massachusetts 88-91 History of glass-making in Missouri 97 History of glass-making in New Hampshire 91-93 History of glass-making in New Jersey 96, 97 History of glass-making in New York 93, 94 History of glass-making in Ohio 97 History of glass-making in Pennsylvania 79-88 History of glass-making in Russia .'. 68,69 History of glass-making in the United States 77-99 History of glass-making in Virginia 77, 78 History of glass-making in West Virginia 78, 79 History of manufacture of plate- glass in France I . . 56 History of some processes of glass-making 56-58 History of the invention of pressed glass 58 Hohenbocka (German ) sand 28 Hohlglas, definition of 21 Holland, glass-making in 70 Holland, present condition of glass-making in 77 Holland, statistics of glass-making in 77 Hollow-ware, the term, applied to bottle-glass 21 Horse-power in glass factories, number of 4,5 Horses in glass factories, number of 4,5 Hot stoking, heat of 43 I. Idle and building glass works, statistics of 2,3, 13, 14 Idle furnaces Illinois, history of glass-making in 98 Illinois sand 29 Illinois, statistics of all works in, by counties 15 Importation of Belgian window-glass into the United States. 63 Importation of German silvered plate into the United States. 70 Imports, British, of glass 72 Imports of glass, early action of Congress in levying duties on. 95 Imports of glass into the United States 99-101 Imports of soda Improvements in the pressing process Impurities in sand and their removal . India, glass-making in . 31 47 24 64 Indiana, manufacture of plate-glass in 99 INDEX TO GLASS. 109 Indiana, statistics of all works in, by counties Influence of barbarians upon glass-making Inlluence of Christianity on the manufacture of glass Influence of Germany on French glass-making Influence of Rome on glass manufacture in Germany Influence of the church on glass-making Influence of the Renaissance on glass-making Influence of the Roman conquest in extending glass manu facture 1 Influence of Venice on modern glass-making Influence of Venice on the manufacture of English glass Influence of weather on composii ion of glass Influence of weather on melting glass Influences that determine the glass mixture Insolubility of glass -- Insulators, method of manufacture of, by pressing Intervals of payment - Introduction of glass-making into Rome Iowa, statistics of all works in, by counties Ireland, glass-making in Iridescent glass, definition of - Iron in glass Iron in sand, effect of, on glass Italian glass manufacture, statistics of Italy, present condition of manufacture of glass in .1. Jamestown, Virginia, glass-making at . Jarves, Mr., on Venetian glass-making. Johnson's Rambler quoted Jo'nt molds Pge. 16 66 63 66 63 65 65 63 64 68 41 41 41 22 48 8 62 16 64 21 33 24 76 76 77 65 22 47 K. Kalt-schiiren .............................................. 44 Keeue, New Hampshire, glass-making at .................... 92 Kensington, Pennsylvania, glass works at .................. 80 Kentucky, history of glass-making in ...................... 98 Kentucky, statistics of all works in, by comities ............ 16 Lablanc's discovery of soda-ash ............................ 31 Labor, division of, at early furnaces ........................ 34 Lamp chimneys, number made ............ . ................ 11 Lamps, number made ...................................... 11 Lamps, pressing ........................................... 48 Lancaster, Pennsylvania, Baron SteigeV's glass works at ..... 80 Lancaster, Pennsylvania, glass-making at .................. 80 Lardner's definition of glass (note) .......................... 19 Largest plates of glass made ............................... 46, 73 Lead, effect of, in the manufacture of glass ................. 33 Lead, effect of proportion of, on time of melting ............ 44 Lead flint-glass, composition of ............................ 19 Lead flint-glass, constituents of .................. .......... 42 Lead flint-glass, English, constituents of ................... 42 Lead flint-glass, French, constituents of .................... 42 Lead flint-glass, manufacture of, in France ................. 66 Lead Hint-glass, Pittsburgh, constituents of ................ 42 Lead flint-glass, proportion of materials used in the manu- facture of ............................................... 42 Lead glass, analyses of ..................................... 23 Lead glass, characteristics of ............................... 21 Lead glass, character of .................................... 33 Lead glass, composition of ................................. 21 Lead glass, early manufacture of ........................... 57 Lead glass, how distinguished from lime glass .............. 21 Lead glass, invention of .................................... 57 Lead glass, where made .................................... 33 Lead, use of, as a glass-making material a modern discovery. 33 Leer, description of ........................................ 51 Legislature, action of early Massachusetts, encouraging glass- making ................................................. 89 Letter of transmittal . . is Pag* Lever-press for making pressed glass, description of 47 Life of pots 41 Lime an important glass-making material 32 Lime, effect of, on glass 32 Lime flint-glass, Bohemian, constituents of 42 Lime flint-glass, clear white, constituents of 42 Lime flint-glass, chemical, constituents of , 42 Lime flint-glass, composition of - 19 Lime flint-glass, constituents of 42 Lime flint-glass, French, constituents of 42 Lime flint-glass, Pittsburgh, constituents of 42 Lime flint-glass, proportion of materials used in the manu- facture of 42 Lime glass, analyses of 23 Lime glass as a rule a cheap glass 32 Lime glass, definition of 21 Lime-glass houses, time of fining in 44 Lime-glass houses, time of melting in 44 Lime present in nearly all glasses 32 Lime, sources of supply of .. 33 Limestone used, amount of 18 Lime used, amount of - 18 Lime, use of, a modern discovery 32 Lime- white flint-glass, constituents of 42 Litharge or red lead used, amount of 18 Litharge, use of - 33 Loans of money to encourage manufactures, constitutionality of, discussed in Congress 9 Localities in which glass was produced 11 Localities of the manufacture of glass in Great Britain 72 Location of ancient factories at mouths of rivers 25 Location of German glass houses 74 Location of plate-glass factories in Europe 70 Location of window-glass factories in Europe 71 London Pottery Gazette on the invention of glass pressing 58 Looking-glass manufacture in Austria, thin sheet glass for .. 44 Loss in melting 44 Loss of plate-glass in grinding, smoothing, and polishing 46 Lottery for raising funds to establish glass-making in New Hampshire 92 Low countries, modern manufacture of glass in 68 Lowell, Massachusetts, early glass works in 90 Lumber used, amount of 18 M. Machinery for grinding plate-glass, description of 46 Machines used in glass works, kind and number of 5 Making soda, Sol vay process for 31 Making soda, the ammonia process for 31 Manganese, effect of use of, on color of glass 25 Manganese used, amount of 18 Manganese, use of 33 Manganese, use of, as a decolorizer 24 Manipulation of glass, devitrification in its relation to 22 Manufacture of beads in Virginia 78 Manufacture of bottles in .window-glass houses 84 Manufacture of bottles west of the Allegheny mountains ... 85 Manufacture of glass in Allegheny county iu the census year. 88 Manufacture of glass in Germany, statistics of 74 Manufacture of glass, use of salt in the 32 Manufacture of salt-cake in the United States 32 Manufacture of soda-ash in the United States - 3:J " Market-money," payment of 8 Martin's Ferry, Ohio, glass-making at TO Marver, use of 51 Maryland, history of glass-making in 95, 9(> Maryland sand 29 Maryland, statistics of all works in, by counties Itj Massachusetts, account of early flint-glass making iu . . 90 Massachusetts, early plate-glass manufacture in WtJ Massachusetts, first glass works iu 89 in; 110 INDEX TO GLASS. Page. Massachusetts, history of glass-making in ................... 88-91 Massachusetts legislature, action of early, encouraging glaSS- QQ making ................................................. Massachusetts, state bounty in, for glass-making ............ 89 Massachusetts, statistics of all works in, by counties ........ 16 Materials, alkalies and other, used in glass-making .......... 30-34 Materials, mixing of ....................................... 41-45 Materials, mixing the, influence of, on the character of the lass Materials, proportion of, used in the manufacture of glass ---- 42, 43 Materials, proportion of, variable .......................... 41-45 Materials used in manufacture of glass, consolidated statis- tics of ................................................... 18 Materials used in manufacture of glassware, value of ....... Mechanical chargers ........... . ........................... 43 Mechanical mixers, use of .................................. 43 Melting .................... ............................... 43 Melting, duration of, in glass houses of Austria-Hungary ---- 44 Melting, effect of proportion of lead on time of ............. 44 Melting, effect of proportion of sand on time of ............. 44 Melting, effect of too long continued ....................... 43 Melting glass .............................................. 41-45 Melting, loss in ............................................ 44 Melting-pots, size of, for manufacture of plate-glass . ........ 45 Melting, time of, depends on furnace, materials, and size of pots ..................................................... 43 Melting, time of, in Bohemian glass houses ................. 44 Melting, time of, in covered pots ............................ 44 Melting, time of, in English glass houses .................... 44 Melting, time of, in French glass houses .................... 44 Melting, time of, in gas furnaces ........ . ................... 44 Melting, time of, in the glass houses of the United States ---- 44 Metallurgical slags, glass and .............................. 59 Metallurgy, influence of, on early glass-making ............. 59 Method of manufacture, classification of glass according to (note) ................................................... 20 Method of manufacture of ancient window-glass ........... 56 Method of washing sand to remove impurities (note) ........ 24 Methods of glass-working ...................... - ........... 45-55 Methods of payment ....................................... 8 Michigan, statistics of all works in, by counties .... ......... 16 Milton vase ................................................ 52 Mineral coal, first use of ..................... . ............. 36 Mirrors, early m auufacture of, in Germany ................. 63 Mirrors, manufacture of, in France ......................... 73 Mirrors, manufacture of, in Germany ....................... 74 Mirrors, production of, in Germany ................ . ........ 70 Mirrors, tin amalgam for, a German invention .............. 63 Mississippi, statistics of all works in, by counties ........... 16 Missouri, history o r glass-making in ........................ 97 Missouri, manufaci ire of plate-glass in ..................... 99 Missouri sand .............................................. 29 Missouri, statistics of all works in, by counties ............. 16 Mixer, Cooper's ............................................ 43 Mixers, mechanical, use of ................................. 43 Mixing-machine, Chance's ...................... ; ........... 43 Mixing materials .......................................... 41-45 Mixing sand used, amount of ............................... 18 Mixing the materials, influence of, on the character of the glass .................................................... 43 Mixture of two or more silicates, glass, a fused .............. 19 Mode of occurrence of French sand ........................ 25 Modern furnaces, description of ............................ 35 Modern glass .............................................. 64-69 Modern glass-making dates from Venice ................... Molded glass, Roman ..................................... Molding articles with lateral designs .................. ____ Molding curved hollow articles . .................. . ......... Mold marks on pressed ware .............................. Molds, blowing in. description of method of ............... Molds, cooling, l>y air blast ..... ......................... . 1148 64 57 47 48 47 51. 49 Molds, early use of Molds for making pressed glass, description of Monkey-ovens in window-glass factories, number of Monopoly of glass-making in Connecticut granted Moore, Governor, on glass-making in New York Mouths of rivers, location of ancient factories at Mules in glass factories, number of 4,5 Murano, establishment of glass manufacture at 65 Page. 57 47 4 94 93 25 IV. Nails used 18 Natron lakes of Egypt 30 Natural glass, definition of (note) 20 Ne wcastle-on-Tyne, glass-making at 64 New England sand 29 New Hampshire, description of early method of glass-making in 90,91 New Hampshire, history of glass-making in .,.. 91-93 New Hampshire, statistics of all works in, by counties 16 Now Jersey, glass sand in 97 New Jersey, history of glass-making in 96, 97 New Jersey, John T. Bodine on early glass-making in 96 New Jersey sand 29 New Jersey, statistics of all works in, by counties 17 New Jersey, statistics of glass-making in, at various dates .. 96 New York, crown-glass making in, iu 1846 94 New York, De Witt Clinton on glass-making in 94 New York, glass-making in, early in the 19th century 94 New York, Governor Moore on glass-making in 93 New York, history of glass-making in 93, 94 New York , statistics of all works in, by counties 17 Nicholson furnace, description of 37 Nicholson furnaces, number of 4 Nitrate of soda used, amount of 18 Nitrate of soda, use of 32 Normandy, glass-making in 63 Norton, Captain, sent to Virginia to make glass 78 Norway, glass-making in 70 Norway, present condition of manufacture of glass in 77 o. Object aimed at in the form of furnaces 35 Obsidian (note) 20 Ohio,history of glass-making in 97 Ohio, stati sties of all works in, by counties 17 Omissions in previous censuses 2 Optical glass 21 Optical glass, character of 4ti Optical glass, Guinaud's method of making 46 Ordinance of Aurelian regarding tribute on glass 59 Ovens used in glass works, kind and number of 5 P. Painted glass a German invention Painted glass, classification of, chemically Painted glass, definition of Painted glass, statistics of, not included in report Palmer, Mr. Charles, on the production of plate-glass in England, France, and Belgium Patent plate, definition of Patent plate, how made Payment, frequency of Payment in kind Payment, methods of Payment, peculiarities of Pearl-ash used, amount of Pelt's hair (note) Pellatt on the invention of glass pressing Pembroke, New Hampshire, glass-making at Pennsylvania, glass works in, in 1810 Pennsylvania, history of glass-making in Pennsylvania, statistics of all works in, by counties 63 20 20 1 70, 71 20 51 18 20 58 92 82 79-88 17 INDEX TO GLASS. Ill Page. Permanent establishment of the manufacture of flint-glass at Pittsburgh 86 Persia, glass-making in 64 Petition of John Frederick Amelung for aid in glass-making. 95 Petroleum, use of 4 Philadelphia, early glass-making near 80 Philadelphia, manufacture of flint-glass in 80 Phoenicia, Aggry beads made in t>0 Phoenician glass 25,60 Phoenician glass, character of 61 Phoenician sand /--. 25 Pittsburgh bottle-glass, constituents of 43 Pittsburgh, history of glass manufactures in. 85-87 Pittsburgh glass houses, sources of supply of sand for 29 Pittsburgh lead flint-glass, constituents of 42 Pittsburgh lime flint-glass, constituents of 42 Pittsburgh, statistics of the manufacture of glass in, for a series of years 87,88 Pittsburgh window-glass, constituents of 42 Plant of factories 4 Plate-glass, analyses of 23 Plate-glass, annealing 45 Plate-glass, annealing-ovens for, description of 46 Plate-glass, casting 45 Plate-glass, capital invested in 3 Plate-glass, chemically, classification of 20 Plate-glass, consolidated statistics of production, etc 11 Plate-glass, coustiluents of 42 Plate-glass, descript ion of machinery for grinding 46 Plate-glass, difficulties in the way of the manufacture of, in the United States 98 Plate-glass, early attempts to make, in the United States ... 98 Plate-glass, English, constituents of 42 Plate-glass factories, definition of 1 Plate-glass factories in Europe 70 Plate-glass, French, character of 69 Plate-glass, French, constituents of 42 Plate-glass, grinding, description of process of 46 Plate-glass, history of manufacture of, in France 56 Plate-glass in the United States, history of the manufacture of 98 Plate-glass, kind of, produced at the different establishments 3 Plate-glass, largest plates made 46, 73 Plate-glass, loss of, in grinding, smoothing, and polishing 46 Plate-glass making in France 1 66 Plate-glass manufacture, early, in Massachusetts 98 Plate-glass manufacture in Belgium, establishment of 57 Plate-glass manufacture in England, establishment of 57 Plate-glass, manufacture of, in Austria-Hungary 75 Plate-glass, manufacture of, in France 73 Plate-glass, manufacture of, in Indiana 99 Plate-glass, manufacture of, in Missouri 99 Plate-glass, Mr. Charles Palmer on the production of, in England, France, and Belgium , 70, 71 Plate-glass, polishing 46 Plate-glass pots, size of 41 Plate-glass, prices of, in Europe 71 Plate-glass, process of manufacture of 45 Plate-glass, statistics of production of 10 Plate-glass, production of, in Belgium 70 Plate-glass, production of, in England 70 Plate-glass, production of, in Europe 70,71 Plate-glass, production of, in France 70 Plate-glass, production of, value of 10 Plate-glass, product of, value of 9 Plate-glass, proportion of materials used in manufacture of. . 42 Plate-glass, relative productive rank of the states in 9 Plate-glass, results of the attempt to manufacture, in the United States 99 Plate-glass, rolling 45 Plate-glass, size of, made at Saint-Gobain 73 Plate-glass, size of melting-pots for manufacture of 41, 45 Plate-glass, smoothing 46 Plate-glass, Thevart's invention of Plate-glass, thickness of Plate-glass, time of melting, in English houses Plate-glass works, furnaces in, number of Plate-glass works, pots in, number of Pliny's story of the discovery of glass Poitiers, glass found at Poitiers, variety of glass found in tombs at Polished plate, definition of Polished plate, establishments producing Polished plate-glass, value per square foot of Polishing-machines in plate-glass factories, number of Polishing plate-glass Pompeii, window-glass discovered at Pontil, use of Portland vase, the Portugal, glass-making in Portugal, present condition of glass-making in Potash, early history of use of Potash, early sources of supply of Potash, use of, recent '.... Pot-clay, American, analyses of Pot-clay, analyses of. Pot-clay, different localities in which produced Pot-clay, preparation of, for making pots Pot-metal Pots Pots, covered, use of, in glass-making Pots, difficulty of setting Pots, drying of Potsherds, use of Pots, how made Pots, life of Pots, number of Pots, shape of Pots, size of Pots, size of, effect of, on time of melting Pots, soundness of, how tested Pots used, number of Power used in glass works Preliminary heating of batch Preliminary report, March 30, 1880 Prepared quartz, sand and, relative cost of, in Vienna Presentation of flint goblets to Washington by Mr. Amelung. Present condition of glass-making in Austria-Hungary Present condition of glass-making in Europe Present condition of glass-making in Germany '. Present condition of glass-making in Holland Present condition of glass-making in Italy Present condition of glass-making in Norway Present condition of glass-making in Portugal Present condition of glass-making in Russia Present condition of glass-making in Spain Present condition of glass-making in Sweden Pressed glass an American invention Pressed glass, ancient, how made Pressed glass, description of process of manufacture Pressed glass, history of the invention of Pressed glass, lever-press for making, description of Pressed glass, molds for making, description of Pressed glass, the first Pressed tumbler, the first Presses in glassware factories, number of Pressing, blowing and, united to produce same form of glass. Pressing bottles Pressing, casting and, relative processes Pressing curved hollow articles Pressing, effect of, in cheapening glass .' Pressing goblets Pressing lamps Pressing, method of manufacture of balls by Pressing, method of manufacture of battery jars by 1149 Page. 56 46 44 3 3 59 63 63 20 3 10 4 46 56 51 52 70 77 32 32 32 40 40 39 40 8b 34,41 57 40,41 40 40 40 41 3 41 41-44 44 41 18 5 43 ix 28 95 74,75 69-77 74 77 76 77 77 76 77 76 58 58 47 58 47 47 58 58 4 45 48 45 48 58 48 48 46 4S 112 INDEX TO GLASS. Page. Pressing, method of manufacture ol insulators by 48 Pressing process, improvements in 47 Pressing taper articles - 48 Prices of plate-glass in Europe 71 Prince Rupert's drops 21,53 Privileges, special, given to glass-makers 63 Prize offered for glass-making 81 Process for making soda, the ammonia 31 Process for making soda, the Solvay 31 Process of manufacture of plate-glass. . ; 45 Productive rank of the states, relative 9 Product of glass, value of 9 Profit in glass-making, no attempt to show ix Properties, composition, and classification of glass 19-23 Properties of glass 21, 22 Proportion of batch in glass houses of Austria-Hungary 44 Proportion of materials used in the manufacture of glass . 41-43 Proportion of silica in glass 24 Quality of American glass (note) 69 Qaality of Belgian glass 74 Quality of Bohemian glass 70, 74 Quality of German glass 74 Qnartz, early use of, in glass-making 26 Quartz still used 27,28 Qnartz, use of, in manufacture of glass 24 K. Rambler, Johnson's, quoted . . 22 Range of -wages 6,7 Raw glass, production of, in Austria 44 Reaumur's porcelain 22 Red lead or litharge used, amount of 18 Red lead, use of 33 Refining glass in Austria 44 Refining, heat of 43 Refining, time of 43 Remains of ancient Egyptian glass furnaces found by Napo- leon 1 60 Renaissance, influence of t,he, on. glass-making 65 Report, preliminary, March 30, 1880 < is Report, this, scope of 1 Revenue scheme, Townsend's, effect of, on glass-making 80 Revival of Venetian glass-making 65 Reworked glass not included in report 1 Richmond, Virginia, manufacture of glass at 78 River or sea sand 25 Rochette of Syria 31 Rolled cathedral plate, definition of 20 Rolled plate 46 Rolled plate, definition of 20 Rolling plate-glass 45 Roman conquest, influence of the, in extending glass manu- facture 63 Roman glass, amount of production of 62 Roman glass, specimens of, found in many countries 62 Roman molded glass 57 Romans, use of window-glass by the 56 Rough plate 46 Rough plate, definition of 20 Rough plate, establishments producing 3 Russia, history of glass-making in 68,69 Russian glass manufacture, statistics of 76 Russia, number of plate-glass factories in 70 8. Saint-Gobain Company 73 Salt-cake, early attempts at the use of Salt-cake first used in the United States Salt-cake, manufacture of, in the United States. Salt-cake used, amount of Salt used, amount of 1150 31 31 32 18 18 Salt, use of, in the manufacture ef glass Salviati and Venetian glass-making Sand . . Sand, American, Bontemps quoted on Sand, American, character of Sand, American, mode of occurrence of Sand, American, Mr. Henry Chance quoted on Sand, American, Thomas Webb & Son quoted on Sand, analysis of, not always indicative of quality Sand and prepared quartz, relative cost of, in Vienna Sand, Austrian, sources of supply of Sand, Belgian, sources of supply of Sand, color of, not always indicative of quality Sand, deposits of American Sand, effect of proportion of, on time of melting Sand, English, analyses of Sand, English, sources of supply of Sand for English glass houses, sources of supply of Sand for Pittsburgh glass houses, sources of supply of Sand for Swedish glass houses, sources of supply of Sand for Wheeling glass houses, sources of supply of Sand, French, analyses of Sand, French, character of Sand, French, mode of occurrence of Sand, German, sources of supply of Sand, grinding, used, amount of Sand, Herzogeurath (German) Sand, Hoheubocka (German) Sand, Illinois Sand, impurities in, and their removal Sandiver, or glass-gall Sand, Maryland Sand, Missouri Sand, mixing, used, amount of Sand, mode of occurrence of Sand, New England Sand, New Jersey Sand of the river Bel us Sand of United States, superiority of the Sand, Phcenician Sand, river or sea Sand, glass, analyses of foreign Sand, glass, analyses of United States Sand, sources of supply of, for Austrian glass houses Sand, Swedish, sources of supply of Sand, tests of Sand used in ancient factories Saxon drinking glasses Scope of report Scotch pot-clay, analyses of Scotland, glass-making in Scott's glass house at Pittsburgh Sea or river sand Sea- plants, soda from ashes of Second attempt at glass-making in the United States Seed in glass, cause of Setting of pots Seybert's Statistical Annals of the United States quoted (note) . . Shape of pots Sheet glass, definition of Sheet glass, thin, for looking-glass manufacture in Austria. _ Si6ge shops worked in glassware factories, number of Siemens, Friederich, quoted on use of alkaline rocks in Ger- many * Siemens' furnaces, number of Siemens' furnace, use of, in the United States Siemens' gas furnaces Siemens' tank furnace Siemens' tank furnace for window-glass, illustration of Siemens' tank furnaces, use of, in Austro-Hungarian glass houses Siemens' tempered glass Page. 3? 65 24-30 26 28 25 26 26 25 28 28 27 25 28 14 20,27 26 27 29 28 29 27 27 25 27 18 28 28 29 24 30, 43 29 29 18 25 29 29 59 26 25 25 29 30 28 28 25 26 63 1 40 64 83 25 31 78 45 41 2 41 20 44 4, 35 28 4 37 36 37,38 39 44 54 INDEX TO GLASS. Page. Sieaens' tempered glass, process of manufacture of Silica in glass, proportion of Siliceous rocks, use of in manufacture of glass 24 Size of Austrian glass pots 41 Size of Bohemian glass pots 41,44 Size of bottle-glass pots 41 Size of colored-glass pots 41 Size of English pots 41,44 Size of flint-glass pots 41 Size of French pots ."- 41,44 Size of furnaces 36 Size of German glass pots. 41 Size of melting-pots for manufacture of plate-glass 45 Size of plate-glass made at Saint-Gobain works 73 Size of plate- glass pots 41 Size of pots, effect of, on time of melting 44 Size of pots in different countries 41 Slag, blast-furnace, a glass (note) 20 Slag glass, color of 55 Slag glass frem blast furnaces 54 Slag glass, manufacture of 55 Smoothing-macliines in plate-glass factories, number of 4 Smoothing plate-glass 46 Soda, ancient, impure - 31 Soda-ash, Lablanc's discovery of 31 Soda-ash, manufacture of, in the United States 32 Soda-ash used, amount of - 18 Soda, Egyptian, where procured 30 Soda from ashes of sea-plants 31 Soda glass, ancient glass a 30 Soda, imports of 31 Soda, nitrate of, use of..-. 32 Soda, production of 31 Soda, sources of supply of, for ancient glass houses 30 Soda, Spanish, of Alicant 31 Soda window-glass, efl'ect of dampness on 30 Soluble glass, definition of .! 21 Soluble glass, uses of 21 Solvay process for making soda 31 Soundness of pots, how tested 41 Sources of supply of Austrian sand 28 Sources of supply of Belgian sand 27 Sources of supply of English sand 26 Sources of supply of German sand 27 Sources of supply of lime 33 Sources of supply of potash, early 32 Sources of supply of sand for Austrian glass houses 28 Sources of supply of sand for English glass houses 27 Sources of supply of sand for Pittsburgh glass houses 29 Sources of supply of sand for Swedish glass houses 28 Sources of supply of sand for Wheeling glass houses 29 Sources of supply of soda 31 Sources of supply of soda for ancient glass houses 30 Sources of supply of Swedish sand 28 Spain, early glass works in 63 Spain, glass-making in 70 Spain, modern glass manufacture in 66,67 Spain, present condition of glass-making in 77 Spain, statistics of glass factories in 77 Spanish barilla 31 Spanish glass, character of modern 67 Spanish soda of Alicant 31 Special privileges given to glass-makers 63 Specialties, England's, in glass-making 69 Specialties, France's, in glass-making 69 Specialty, Austria-Hungary's, in glass-making 70 Specialty, Belgium's, in glass-making 69 Specialty, Germany's, in glass-making 70 Specific gravity of glass 21 Specimens of Roman glass found in many countries 62 Spun glass, definition of 21 Stained glass, definition of 1 20 Page. Stained glass, French 09- Stained glass, statistics of, not included in report 1 State bounty in Massachusetts for glass-making 89 State of the art in ancient Egypt 59 States, relative productive rank of the 9 Statistics for 1870 2 Statistics for 1880, summary of 1 Statistics of all the glass works of the United States, consoli- dated, by states 15 Statistics of all the glass works of the United States, by states and counties 15, 16, 17 Statistics of glass factories in Spain 77 Statistics of glass-making in Austria-Hungary 75 Statistics of glass-making in Belgium 74 Statistics of glass-making in Connecticut at various dates. . . 95 Statistics of glass-making in Great Britain 72 Statistics of glass-making in Holland 77 Statistics of glass-making in Italy 76 Statistics of glass-making in New Jersey at various dates % Statistics of glass-making in Norway 77 Statistics of glass-making in Pittsburgh for a series of years. 87, 88 Statistics of glass-making in Russia 76 Statistics of glass-making in Sweden 76 Statistics of glass-making in Venice 76 Statistics of idle and building glass works ..2, 3, 13, 14 Steam-engines in glass factories, number of 4,5 Steigel's, Baron, glass works, at Lancaster 80 Stirring of the materials, how accomplished 43 Store-pay 8,9 Stonrbridge pot-clay, analyses of 40 Strass 21 Strass, nse of, in imitations of precious stones 46 Straw and hay used, amount of 18 ! Strength, crushing, of glass 21,22 Strength, tensile, of glass 21,22 i Striae in glass, cause of 45 Strings in glass, cause of 45 Sulphate glass 31 Summary of statistics for 1880 1 Superiority of the sand of the United States 26 Sweden, glass-making in 70 Sweden, present condition of manufacture of glass in 76 Sweden, statistics of glass manufacture in 76 Swedish glass houses, sources of supply of sand for 28 Swedish sand, sources of supply of 28 Syria, rochette of. 31 T. Tank furnace for window-glass, illustration of Siemens' 39 Tank furnaces, general description of. 39 Tank furnace, Siemens' 37, 38 Tank furnaces, number of 4 Tears in glass, cause of 45 Tear-sown bottles 61 Teaser, duties of 43 Tempered glass 52 Tempered glass, defects of 53 Tempered glass, definition of 21 Tempered glass, Siemens, cost of 54 Tempered glass, Siemens, tests of 54 Tempered glass, Siemens, uses of 54 Temple, New Hampshire, glass-making in 91 Tensile strength of glass 21,22 Tension of glass 21 Tests of sand 25 Theophilus' account of blown window-glass 57 Thevart's invention of plate-glass 56 Thickness of plate glass 46 Thin pots, nse of, in France 44 Thin sheet glass for looking-glass manufacture in Austria 44 Threads in glass, cause of 45 Time occupied in melting 43 1151 114 INDEX TO GLASS. Page- Time of cooling 44 Time of fining in English houses 44 Time of fining in lime-glasshouses 44 Time of fining in the glass houses of the United States 44 Time of melting crown-glass in English houses 44 Time of molting depends on furnace,'materials, and sizeof pots. 43 Time of melting, effect of proportion of lead on 44 Time of melting, effect of proportion of sand on 44 Time of melting, effect of size of pots on 44 Tin amalgam for mirrors a German invention 63 Tomlinsou's classification of glass (note) 20 Tools used in the manufacture of flint-glass Toughened glass Toughened glass, definition of Townsend's revenue scheme, effect of, on glass-making Transmittal, letter of --- Transparent glass, earliest specimen of 61 Tribute on glass, ordinance of Aurelian regarding 59 Truck payment Tumblers, number made Tumbler, the first, pressed 58 V. United States, first glass house in the 77 United States, glass sands of the, analyses of the 30 United States, history of glass-making in 77-79 United States, history of the manufacture of plate-glass in the. 98, 99 United States, imports of glass into the 99-101 United States, results of attempts to manufacture plate-glass in the 99 United States, salt-cake first used in the 31 United States, second attempt at glass-making in the 78 United States, superiority of sand of 26 United States, time of fining in the glass houses of 44 United States, time of melting in the glass houses of 44 Ure's definition of glass (note) 19 Ure's classification of glass (note) 20 Use of flint in manufacture of glass 24 Use of glass in ancient Rome 62 Use of quartz in manufacture of glass 24 Use of window-glass by the ancients, extent of 56 Uses of soluble glass 21 Uses of water glass 21 V. Varec of Bretagne 31 Variability of composition 19 Varieties of Egyptian glass 60 Variety of early glass 34 Variety of glass found in tombs at Poitiers 63 Variety of Roman glass 62 Vases de verre, manufacture of, in France 66 Vehicles used in glass works 5 Venetian glass 70 .Venetian glass-making, early ,. 65 Venetian glass-making, revival of . 65 Venetian glass manufacture 76 Venice, glass-bead manufacture in 70 Venice, influence of, on modern glass-making 64 Venice, influence of, on the manufacture of English glass 68 Venice, modern glass-making dates from 64 Vermont, history of glass-making in 97 Virginia, Captain Norton sent to, to make glass^ -v. 78 Virginia, history of glass-making in 77, 78 Virginia, manufacture of beads in 78 w. Wages, annual settlement of Wages paid 6 Wages, range of 6,7 Wagons in glass factories, number of 4,5 Washing sand, method of, to remove impurities (note) 24 Washington, presentation of flint goblets to, by Mr. Amelung 95 Water glass (note) 20 Water glass, definition of 21 1152 Page. Water glass, uses of 21 Watson, Elkanah, on glass-making in Albany 93 Waves in glass 45 Wearing fabrics, glass, manufacture of, in Austria-Hungary . 75 Weather, influence of, on composition of glass 41 Weather, influence of, on melting glass 41 Webb, Thomas, & Sou, quoted on American sand .* 26 Wellsburg, West Virginia, manufacture of glass at 78 West Virginia, history of glass-making in 78, 79 Wheeling, gas furnaces at 79 Wheeling glass houses, sources of supply of sand for 29 Wheeling, West Virginia, history of glass-making at 78,79 White glass, French, character of 69 Winckelman's views on the antiquity of window-glass 5G Window-glass, analyses of 23 Window-glass, ancient, character of 56 Window-glass, average value per box of 10 Window-glass, Belgian 69 Window-glass, Belgian, importation of, into the United States 69 Window-glass blowing 50 Window-glass, bjown, early manufacture of 57 Window-glass, blown, Theophilus' account of 57 Window-glass, capital invested in 3 Wiudo w-glass, classification of, chemical 20 Window-glass, composition of 19 Window-glass, consolidated statistics of, production, etc 12 Window-glass, constituents of 42 Window-glass cylinders, how opened 50 Window-glass, decoration of, in France 73 Window-glass, defects of 50 Window-glass discovered at Pompeii 56 Window-glass, English, constituents of 42 Window-glass, extent of use of, by the ancients 56 Window-glass factories, definition of. 1 Window-glass found at Pompeii, analysis of 56 Window-glass, French, constituents of., 42 Window-glass in Germany, early manufacture of 63 Window-glass known to the ancients 56 Window-glass, largest size of, made 51 Window-glass manufacture in Europe 71 Window-glass, method of manufacture of 50 Window-glass, method of manufacture of ancient 56 Window-glass, number of boxes made 10 Window-glass, Pittsburgh, constituents of 42 Window-glass, price of, in 1797 ' 83 Window-glass, product of, value of - 9, 10 Window-glass, proportion of materials used in the manufac- ture of 42 Window-glass, relative productive rank of the states in 9 Window-glass, Siemens' tank furnaces for, illustration of... 39 Window-glass, size of 20, 51 Window-glass, time of melting in English houses 44 Window-glass used in Great Britain in the Roman period ... 56 Window-glass, early use of 56 Window-glass works, early, in England 56 Window-glass works, furnaces in, number of 3 Window-glass works in the United States in 1787 83 Window-glass works, pots in, number of 3 Women, number of, in glass factories 6 Women, work of, in glass factories 6 Wood ashes, potash made from 32 Wood furnaces, number of 4 Wood used, amount of 18 Work.of children in glass factories 5 Work of women in glass factories 5 Work of youths in glass factories 5 Works building in census year, statistics of 3,13,14 Works i die in census year, statistics of 2,13, 14 V. 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