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 6 
 
CENTENNIAL SUPPLEMENT 
 
 ALBUM OF CLARKE, REEVES & CO. 
 
 PHOTOGRAPHS. 
 
 NO. 
 
 I, sand 3. Bridge over Hudson River at Albany. 
 4 and 5. Girard Avenue Bridge, Philadelphia. 
 
 6. VVaterville, Maine. 
 
 7. Ticonic, " 
 
 8. Biddeford, 
 
 9. Miramaclii, New Brunswick. 
 
 10. Deep Gorge \'iaduct. 
 
 11. Brunswick, Maine. 
 
 
 - PLANS. 
 
 
 
 
 12. 
 
 .Albany Bridge, 
 
 70 
 
 feet 
 
 spans 
 
 '3- 
 
 tt (( 
 
 177 
 
 i i 
 
 it 
 
 14. 
 
 ti It 
 
 Pivot draw. 
 
 '5' 
 
 Havre ile Grace, 
 
 307 
 
 feet 
 
 span. 
 
 16. 
 
 Miramaclii, 
 
 200 
 
 i i 
 
 (( 
 
 'T- 
 
 Gii-ard Avenue, 
 
 200 
 
 t i 
 
 ti 
 
 IS. 
 
 Montreal and Ottawa, 
 
 200 
 
 tt 
 
 ti 
 
 H). 
 
 a ti 
 
 '.SO 
 
 It 
 
 (( 
 
 20. 
 
 New Orleans anil Mobile, 
 
 104 
 
 i i 
 
 ii 
 
 21. 
 
 Lewiston, Niagara, 
 
 600 
 
 i( 
 
 (( 
 
 22. 
 
 Kapailo Viaduit. 
 
 
 
 
 23- 
 
 'riianicsville. Canada, 
 
 •S5 
 
 it 
 
 tt 
 
 MODELS. 
 
 24. Pivot draw bridge. Locking apparatus. 
 
 25. Part of a 200 feet ^pan. 
 
 26. Model of a viaduct. 
 
 27. t 'oniiections of viaiUu t. 
 
 SPECIMENS OF IRON. 
 
 2.S Phienix coluunis. 
 
 2<). Die forged eye bars. 
 
 30. li.ir iron, bent and broken. 
 
 }i. Pieces cut out of PJKLMiix (oiuinn. 
 
 Wc >ubinit the above pliotogr.ipiis, plai\s, models 
 .md iron ^pc( iniens, as illustrating the American st\le 
 (if iron bridge building, and in p.irtii ul.ir that system 
 adopted at the Plneniwillc < i'.i 1 Bridge Works, which 
 u>es Piiienix columns for the compressive members, eye 
 
 bars, die forged by hydraulic pressure, for the tension 
 members, and rolled or riveted beams for those mem- 
 bers subject to transverse strains. These parts are 
 united by short castings, pins, screws and nuts, as is 
 plainly shown in the models. 
 
 The accuracy of workmanship is such, that when a 
 bridge is erected and loaded for the first time, and the 
 load then removed, it will return to the ( alculated 
 camber, which is usually taken at 1-1200 of the span. 
 
 Although we do not refuse to construct riveted lat- 
 tice bridges, yet for all spans over 100 feet, we prefer 
 the above described style of bridge, for the following 
 ! reasons : 
 
 1. It has greater strength with e(iual weight, or equal 
 
 I strength with less weight of iron. For the proof of 
 j this we refer to the table of bridges following. 
 
 2. It necessarily reipiires better quality of iron, and 
 b'-tter workmanship than the riveted lattice ; at no 
 greater, and in long spans, at much less cost. 'l"he 
 
 , method of manufacture itself guarantees a better quality 
 
 of iron, and from al! fitting being done by machine 
 
 ' tools, better workmanship. This accuracy is always 
 
 i tested before each span leaves the works, by putting 
 
 j one truss together there. As all engineers know, very 
 
 [ few riveted lattice bridges will come together without 
 
 "drifting" the holes, and there is always a deflection 
 
 after the staging is removed, from the dead weight of 
 
 the bridge itself. 
 
 3. Tiiere is less exposure of surface to wind and 
 weather, and hence greater durabilitv. It has some- 
 times been stated as an ohjec ticui to the PlKunix 
 column, that a brush cannot l)e introduced to paint the 
 inside after erection. This is true ; but it is also true 
 that the interior of these tubes can be [laiuted bv 
 the same process by which the tubes of the Saint Louis 
 bridge were painted at'ter erei tion, vi/ : by filling each 
 with licpiid paint, and letting it itni out into a vessel, and 
 using the residue over again. This was proved to take 
 more paint, but less labor than the usual mode of painting 
 by brush, it is only ne<ess.iry to leave the lower |)art 
 of these tubes open, so that any water that gets in can 
 
Pn(ENlXVILLE BRIDGE- WORKS. 
 
 run out, and the ])aint on the inside will last much 
 longer than the paint on the outside, which is exposed 
 to sun, rain and sudden changes of temperature. As a 
 proof of this, we refer to the specimen pieces (No. 31) 
 cut from Phcenix columns, and showing that the paint 
 has not deteriorated after twelve years. 
 
 4. The pieces being small, and the total weight less 
 than of riveted bridge.^, the cost of transportation is 
 much less. 
 
 5. The necessary time re([uired to erect a pin con- 
 nected briilge of 200 feet span, after the false works cr 
 staging are put in up to the level of bottom chord, does 
 not exceed two to three days. .-V riveted lattice of the 
 same span would take as many weeks. As our rivers 
 are subject to heavy freshets-, the risk of loss would 
 be much increased, .\fter the bridge is erected, the 
 ends of the screw bars of the lateral brace rods, floor 
 hangers and counter tie rods, can be cold riveted over 
 
 the heads of the nuts, and thus make the bridge as 
 immovable as if rivets, headed while hot, were used in 
 connecting the parts. 
 
 6. We believe that owing to the concentration of 
 material along the lines of strain, and hence the greater 
 massiveness of parts, that our bridges will resist the 
 shocks caused by collisions or derailment of trains, as 
 well as bridges with riveted connections. Experience 
 seems to confirm this view, as some of our bridges have 
 beer, exposed to severe shocks of this kind, and in no 
 instance have suffered any material injury. 
 
 To illustrate how much less iron is required to meet 
 the necessary loads and strains by the American system, 
 than by the riveted lattice system as practiced in Englai-.d 
 and on the continent of Europe, we give a table of the 
 weights of some of our bridges as constructed, together 
 with the loads they are designed to carry, and the 
 strains ujjon the iron. 
 
 
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PHLENIXVILLE BRIDGE- WORKS. 
 
 30 
 
 From the preceding table, it will be seen that while 
 the factor of safety of these bridges is ample, compared 
 with their loads (see Album, pp. 22 and 23,) the amount 
 of iron required is less than that required by bridges 
 with riveted connections, and that this economy of 
 material increases very rapidly with the length of span. 
 For short spans of less than 100 feet, economy of 
 weight is not desirable, and for this class of bridges, 
 we do not consider that riveted lattice girders are ob- 
 jectionable, as the difficulties of connecting together the 
 parts by riveting which increase with the length of 
 span, do not show themselves in these short spans. 
 
 The best bridges will always be built by those who, in 
 addition to the theoretical knowledge of construction 
 possessed by them in common with other engineers, have 
 also that e.xperience which practice can alone give. 
 
 It has been well said*' "that bridges do not fail from 
 mistakes in calculating the strain sheets, but from the 
 effects of vibration, buckling and rapid wear of import- 
 ant jjarts ; the use ot shapes that weaker, the materials ; 
 inetiualities in the material itself; and from similar 
 causes not stated in the books ; which assume cfifferent 
 as])ects under every change of proportion and dimen- 
 sions; and which can only be inferred by means of a 
 long familiarity with the behavior of similar structures 
 during various periods of service, and with the processes 
 by which materials and members an? made." 
 
 It is on this account that we call uarticular attention 
 to the great number of bridges that we have constructed 
 between 1869 and the present time. We examine these 
 bridges at intervals of not over two years, and their 
 behavior under traffic is reported to us. We know the 
 
 ■* Aililrcss of A. L. Hollev, hefore Institute of Miniiiij Kngineers, 
 at Washington, Februaiy 221I, 1S76. 
 
 condition of all the parts, and if anything re(iuires to be 
 done, we either do it ourselves, or call the attention of 
 the officers of the railway, or those in charge, so that 
 they may do it. 
 
 We are thus enabled to im])rove our designs froin 
 year to year, although we have found nothing radically 
 wrong which would impair the safety or durability of 
 our bridges. 
 
 The amount of bridges built by Clarke, Reeves & Co., 
 between 1869 and the present time, is as follows : 
 
 Number of s|)ans 46 2 
 
 " of lineal feet of single 
 
 track, 54,050 
 
 Number of tons of iron besides 
 roofs and other iron 
 work 22, 000 
 
 The above bridges have been constructed at Phcenix- 
 ville in accordance with our own designs. There have 
 been built at Plueni.wille for other engineers, on their 
 designs, during same time : 
 
 Number of spans, 285 
 
 " oflineal feet, 25.220 
 
 " of tons of iron, 0,000 
 
 And the total is, 
 
 Number of spans, 747 
 
 " oflineal feet, 79,270 
 
 " of tons of iron, 31,000 
 
 We call the attention of foreign engineers to the 
 Girard Avenue Bridge, as a specimen of our bridge 
 work, near at hantl and easily inspected. We extract 
 from " London E^ngineering," of November 19th, 1875, 
 the following description : 
 
 
GIRARD AVENUE BRIDGE. 
 
 GiRARD Avenue Bridge, of wliich we gave a two 
 page and other engravings in our last number, anil 
 whicj-i we further illustrate in our present issue, spans 
 the Schuylkill river in the city of Philadelphia, at the 
 main avenue of approach to Fairmount Park and the 
 Exhibition buildings, and isone of the great public works 
 that will interest visitors to the Centennial Exhibition. 
 
 It is remarkable as the first atlempt in the United 
 States to combine the American system of ])in-jointed, 
 openwork girders, distinguished for their lightness of 
 appearance, with a solid roadway of stone, i onstructed 
 in that massive and substantial manner which is custom- ! 
 ary in England and on the Continent. To this is i 
 added a higher degree of architectural ornament than is 
 common even here. j 
 
 Its dimensions and cost do not differ much froni our 
 recent first-class bridges over the Tiiames, as will be 
 seen from the following table ; I 
 
 I 
 
 Names. 
 
 _^ S(|uare 
 -S Feel of 
 > Surface. 
 
 Cost. :r|| 
 
 freshets, and of forming a pool of still water through 
 wiiich the concrete could be lowered without its current 
 being washed out. This dam was carried 20 feet above 
 low water, or above the level of the higiiest floods. .Ml 
 this work above the crib was temporary, and removetl 
 after the construction of the pier. The internal space 
 of the crib was then cleared by divers, using a centri- 
 fugal pump, wiiich sucked the rock clean. 
 
 rhis interior sjjace, 22 feet wide b} 137 feet long by 
 16 feet high, was then filled with beton made as follows : 
 Furnace slag was broken up by a Mlake crusher, so as to 
 pass 2 inch meshes, liy placing this' in a measured 
 barrel of water the proportion of voids to solids was 
 found to be exactly as i to 2. 
 
 A mortar was then made of one part of Pennsylvania 
 hydraulic cement from the Coplay Works, and one part 
 of clean sharp sand, the mixture staniling thus : 
 
 ,, . , p,, , f I iiart Coi)lay ( ement. 
 
 ^'"•^1^ ""^•^' ' -^ I I part sand. 
 
 Solid 
 
 I 4 parts crusiied fur- 
 
 £ , £ 
 
 London 9^4 53.'-' 47-3^4 542,150 11 o 
 
 Waterloo 13S041IJ 57.27° 579'9i5 1° o 
 
 Southwark !Soo42j_i 34,000 384,000 11 o 
 
 Westminster 116085 98,6co 393,oyo ; 4 o 
 
 lllackfriars 127276 96,672 320,000} 3 6 
 
 Girard 1000 100 100,000 267,500 ' 2 13 
 
 The height of the roadway above low water is 55 feet. 
 The girders rest on three piers and two abutments, and 
 form three centre s[)ans of 197 feet eacii and two side ; 
 si)ans of 137 feet each. The height of the lower chord \ 
 above low water is 23 feet. The bridge has a camber 
 of 18 inches in its total length. 
 
 Foiiiiiiations. — The foundations of each pier were con- 
 structed, as follows: The debris was removed from the 
 ro<:k bed of the river 30 feet below low water, by the com- 
 mon .Vmerican single-bucket steam dredging machine. 
 A double-walled bottomless caisson, 34 feet wide by 156 
 feet long, having the ends pointed, and formed of foot- 
 s(iuare timbers well bolted together in tiie usual Amcii- 
 can manner of forming 'criltwork,' was sunk upon the 
 bare rock, its bottom timbers having been carefully 
 scribed to fit the inecpialitiesof the surface. The spaces 
 between the double walls were then filled with loose 
 stone. The top of this cribwork came to witiiin 16 feet 
 of tiie surface of low water. The sides were then car- 
 ried up by means of upright timbers placed 6 feet apart, 
 and planked with 2 inch plank. This formed a coffer- 
 dam, not strong enough to be pumped out, but capable 
 of excluding the current of the river, even during 
 
 nace slag. 
 
 This beton was mixed by hand on platforms, until 
 each stone was tlu)roughly coated with mortar. It was 
 then lowered in a box so constructeil as to (piite protect 
 it against wash during descent, and easily discharge it 
 after touching bottom. It was laid in 12 inches deep 
 courses, carefully levelled by divers. This beton bore 
 by test 30S pounds ])er sipiare inch on cubes 3 inches 
 square, after 30 da)s' immersion. The extreme pres- 
 sure from bridge and maximum load is 45 jjounds per 
 square inch, or less than 3 tons per sipiare foot. .No 
 sign of settlement or cracking has shown itself in any 
 l)art of the structure. 
 
 The foundations of the abutments were made in a 
 similar manner, except that a cofferdam of 12 inches by 
 12 inches siieet piles took the place of the cribwork 
 caissons, anil the earth was removed by a clam-shell 
 dredge of the ])attern so successfully used by Mr. C. S. 
 Gzowski,at the International IJridge over Niagara river. 
 
 The masonry of the piers and abutments is rock-faced 
 ashlar of Maine granite laid in mortar of one p.irt 
 Coplay cement to two [)arts of sand. The courses are 
 from 20 inches to 30 inches high, stretchers friim 5 feet 
 to 7 feet long, with as much bed as rise. There is one 
 header to every two stretchers reaching into tlie pier 
 more than half its width. The courses bond on each 
 other not less than their de[)th. The backing to tiiis 
 face-work is of concrete, made as heretofore described. 
 The copings and parajiets are of finely cut granite, but 
 no other cutting has lieen done, exce|)t the necessary 
 drafts, the object being to preserve the massive effect of 
 rock-faced granite work. 
 
 3' 
 
4 
 
 PHCENIXVILLE BRIDGE- WORKS. 
 
 32 
 
 Supi'r<:tnicture.— X\\>ix<t are seven lines of trusses or ings of galvanized iron tubes with bron/e ornaments, 
 girders placed siile by side 16 feel apart, and united by and are supported by cast-iron standards at every 6 feet, 
 horizontal and vertical bracing. Every eighth standard is prolonged into a lamp post. 
 
 'I'iiese trusses are of the well-known Phicnixville pat- '\ There are eight refuge bays, each of which contains a 
 tern of quadrangular girder. The upper compressive | cluster of six lami)s, tlie supporting shaft rising through 
 members ukI the vertical posts are Phciinix flanged \ an octagonal seat, wliich forms its base. The outer 
 columns, united by cast-iron joint b.ixes. The lower balustrade and cornice is of cast iron with bronze open- 
 chords and diagonals are Fhienix weldless eye-bars, die : work panels, and treated in a highly ornamental manner, 
 forgeil by hydraulic pressure. Upon the tops of the | The bronze panels represent various birds and foli- 
 posts, 12 feet apart, are laid heavy 51 inch I'hfcnix i age, such as the [jhienix, swan, heron, owl, eagle, 
 rolled beams, and iqK>n these longitudinally 9 inch . tobacco, ivy, Virginia creeiier, ferns and hoi)s. These 
 beams placed 2 feet 8 inches apart. These are covered panels are of statuary bronze, cait under a pressure of 
 transversely witli rolled corrugated plates '4 inch thick, 60 lbs. per sipiare inch, which forces the metal into all 
 corruL;ated I '4.' inches high by 5 inches wide. 'I'hese the finest lines, and makes an extremely sharp casting ; 
 tbrm an unbroken iron platform upon which theasphalte so sharp, indeed, that a casting made by this process 
 concrete is placed. from an electrotype, has l)een used to print engravings 
 
 The dead load of the structure with a moving load of from. Tliere are between eight and nine hundred of 
 100 lbs, per square foot makes a total load of 30,000 these bronzesset in the balustrade, like pictures in a frame, 
 lbs. per lineal foot, carried by seven trusses. j^ jj. intended, at some future day, to place sidewalks 
 
 Tiie limit of strain is 10,000 lbs. per siiuare inch, re- i„si(lf the l)ri(lge, at the level of the lower chord, 
 duced to 6000 lbs. pe- square inch as the compressi-.e , Access to these will be gained through the arched open- 
 limit on posts. All poi:us of contact are either planed 1 i,-,g^ j,^ fj^y abutments, and this spot has been selected 
 or turned. The jiins are of cold rolled iron, and the ^^^ ,^ proper place for a drinking fountain. The bri !ge 
 limit of error between pin and hole is one sixty-fourth j^ painted salmon color, relieved by blue and gold ; the 
 of an inch. cornice and balustrade are green and gold. 
 
 The iron used in this bridge is double refined, 'pi^jg p-ridge, notwithstanding its thorough construc- 
 or of •' I'hienix best best " brand, capable of bearing ; ^jq,., .^,„i -^^^ large dimensions, was built in a remarkably 
 the regular test of that quality of iron as follows :, j.],ort sjjace of time as compare<l with works of similar 
 lllim.ite strength, 55,000 lbs. to 60,000 lbs. per scjuare ; magnitude. .Vs tlv. new bridge occupied the exact site 
 inch ; no permanent set under 27,000 lbs. to 30,000 lbs. ; „,■ ^1,^, ^,1,1 o,-,^.^ j[ ^^.^^ necessary, first, to build a temira- 
 ])er square inch ; average reduction of area at iioint of ^.ji.y ijrjdge 1050 feet long and 50 feet high above water, 
 fracture 25 percent. The eU ligation of a 12 in. bar divided into spa-s of 100 feet each, resting on wooden 
 
 is IS perient. ; and the cold bent of a I'j in. round 
 bar bet'ore cracking, iSo degrees, or hammered flat. 
 
 A'.'.r/.v'iM'. — 'l"he corrugated iron jilaies which cover 
 the bridge are themselves ( overed by 4 inch to 5 inch 
 of a>phah, making ,1 water-tight surfice. The ico feet 
 of width is divided into Cy'j feet of carriage way. and 
 two 1 6 '4 feet sidi.'w.ilks. The ro.ulway is pas'ed with 
 granite blocks in tiie usual manner, excejit that it is di- " l'""M""K 
 vided into seven ways by two lines of iron tr.u kways 
 next tile sidewalks for lior>e t ars, .md <\sit lines of car- 
 
 cribs filled with .itonj. This was ilone in six weeks. 
 
 '!'' '; construction of the permanent new bridge began 
 May n. 1873, and July 4, 1S74, it was formally opened 
 for public travel, and iias remained in use ever since. 
 
 Thi^> rajiiditv of construction is due. first, to the mode 
 
 adopted of laying the toundation under water, instead 
 
 )ing out that water; second, to the foreiliought 
 
 lisplaved in making the temporary works strong enough 
 
 to pass uninjured through a freshet which in< reased the 
 
 dejilh of water from 30 feel to 46 f>-'i-'l ^ third, to the 
 
 ria"e tr.imwavs, made of cut gr.mi'e blo( ks. 1 foot wide. . , . ,,,,,,,,,,,.,. 
 
 "•■^^' - ' '^ , . iie.uli.ir (oustruclion ot the girderM whuh (onlam o\ei 
 
 urli>lones are ol 1 , . 
 
 l.iid to a 5 feet guage. The gutters am 
 line 1 ul gnnitc. The sidewalks are < overed fi)r 10 teel 
 of their width, with bl.ick l.ehigh county slate tiles, 2 
 It. ^qu.uc, l.iid diagon illy. 
 
 ( >n ea' h side '■I'i ihe sl.ue tiles are spaces 2 feel wide, 
 whu h were orij^inally laid with em aiMi( lile>. .\flcr 
 one winter's frost tiiese tiles becune so mui h >li,mered 
 ih.ii ihev were removed. ,ind while m.irble tiles >ul)sii- 
 luted ni their |il.iie. The < urbitone, iS inches wide, 
 makes up the remainder of ilie ifi'^ feel. 
 
 i'he sidewalks .\re>cp,ir.iU'il from the ro.idway by r.iil- 
 
 3500 toiisol irmi 1, wliiiii were made at I'lueniwille from 
 ihe ore, eiiinelv by mac hinery, and without any hand 
 labor ; and. lastly, l<> the r,q>idity and fa( ility of erection 
 allowed by the pin-connected mode of construction. 
 
 The general cliniensious of this bridge were fixed by 
 .Mr. S.imuel I,. > aeilley, City Kngineer of I'hiiadelphia ; 
 while the design and c on^tniction are by .Messrs. I'larke, 
 Reeves iS: Co., of the IMicenixvilie liridge Works, whose 
 iron bridge^ and viaduc t> are known in all parts of the 
 world,