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Lorsque le document est trop grand pour dtre reproduit en un seul cliche, il est film6 d partir de Tangle supdrieur gauche, de gauche d droite, et de haut en bas, en prenant le nombre d'images ndcessaire. Les diagrammes suivants illustrent la mdthode. / errata id to nt ie pelure, 9on d 1 2 3 32X t 3 ' * s 6 < .1 OK ^^ \ \ m ''&M- i'i-(SBiii > Y: ^ 1*, >«■! i -J fiii .'i ti ^1 ■ * y I GENERAL INSTRUCTIONS VOK lLlKI5a THB et(0r0l0gical #lji5erljatton$ AT THB SENIOR COUNTY GRAMMAR SCHOOLS IN ^^ UPPER CANADA. ^^^^^'''^^^''^ Authorised and required by the Orammar School Act, 16 Vict., c. 186, iStfc. JCVI. PSBFARED UNDER THE AUTHORITY OP THE CHIEF SUPERINTENDENT OP EDUCATION, BY THE DIRECTOR OP THE MAGNETICAL OBSERVATORY, TORONTO. '* :9lpprotit) i>9 CounctUf pHbl'tc Jn0tructt0n, llppd €anaH, Utft Jul9, 1861. HOUSE LIBRARY, & LIYOU COUEee. MONTRCM. » I ((l^ TORONTO: ^rintrtt for tfit Sfpsctmtnt of public Sitstruttfan foi Wiffit Sanata, BY LOVBLL & GIBSON. 1857. m J ''^ef^"'tH''"' -^'^ • 1 '4ii\ has -, * > ' -3 ( /; met '.r\.!' and •-=fS> ' vari ..;..?.-» dua ^ ^ Uni * ' ' . terr . ^■-.^. mac .t •' ** plai < ' T f 'f . -. and reqi -i-^ pars sboi ,.-r:->-,v exis ■ * ';.*■ will »5 Y-' and - It 'tmrr ■.^'i ; - ' i ■' ,.-''^.^;, -f ' ■ ,'i \f :'-jrm. -■• ■ ■-■' "■■' ■■■■■"■• ' ■? • edu( '.. ' ^:J. '■■i.'". -■■-," -" ' "■ „ '" /''^ enco y-.f-^'-j ■--^-■^_ ■- - ■■■■-■.,":.- ledg 1 *. i^k.-^ >;,.. . PREFATOEY REMARKS. JSs .;l ' 1 ''i-*\ . .- ". -.K f ifi^jj :sws- ■??"'i The prosecution of enquiries relative to atmospheric phenomena has occupied of late years much public attention. Provision for meteorological research in connection with exploring expeditions, and through numerous fixed observatories has been made by the various governments of Europe, and by the liberality of indivi- duals. These efforts have not been confined to Europe ; in the United States of America, a system co-extensive with those territories is in operation, by which the records of observations made at some hundreds of stations, and according to a uniform plan, are regularly transmitted to Washington. To elucidate the climatology of North America, however, and to trace its atmospheric phenomena to their origin, it is requisite that the vast, but (as regards its meteorology,) com- paratively unexplored regions forming the British dominions, should be occupied by stations for observation ; for till the existing meteorological system shall have been thus extended, it will be inadequate to cope with the problem of American storms, and other questions of great practical interest. It was from considerations such as the fo! going, and with a view of remedying the defect so far as relates j Upper Canada, that the Provincial Legislature passed the Act which provides that meteorological registers be kept at the senior County Gram- mar Schools. . The clause referred to is as follows : — " And whereas it is desirable at all seminaries and places of education, to direct attention to natural phenomena, and to encourage habits of observation ; and whereas a better know- ledge of the climate and meteorology of Canada, will be service- IV able to agricultural and other pursuits, and be of value to scientific inquirers: Be it therefore enacted, that it shall be part of the duty of tho master of every senior County Grammar School, to make the requisite observations for keeping, and to keep a meteorological journal, embracing such observations, and kept according to such form as shall from time to time be direct- ed by the Council of Public Instruction, and all such journals or abstracts of them, shall be presented annuall}' by the Chief Superintendent of Education, to the Governor General in his Annual Report." It is earnestly desired that the gentlemen whom this law con- cerns as well as others disposed to bestow their voluntary aid, will conscientiously labour to carry the provisions of this law into effect. In submitting to the restraint that these observations demand, they should be supported by the recollection that the work they are engaged in is a great one, and likely to issue in results not only of speculative interest, but of great practical benefit to societv. To ensure the uniformity in taking and recording observations that is essential to their utility, the following instructions have been drawn up. As they relate to little more than to matters of routine, observers desirous of additional information are referred to books which treat upon the subject, and which may be obtain- ed on application, at the Department of Public Instruction at Toronto. Particular attention is called to the synopsis at the end of Section III., Art 53. » [g. t. k.] value to ; shall be Grammar g, and to tions, and be direct- purnals or the Chief ral in his J law con- ntary aid, is law into iservations n that the ;o issue in ; practical )servations itions have matters of re referred be obtain- ruction at tpsis at the [q, t. k.] GENERAL INSTRUCTIONS FOR METEOROLOGICAL OBSERVATIOI^S. S E C T I N I. METEOROLOGICAL INSTRUMENTS. Art. 1. — The Barometer. The pressure exerted by the atmosphere on a unit of surface is numerically expressed by the height in inches of the column of mercury in a barometer, measured from the surface of the mercury in the cistern, the specific gravity of the mercury being that which it has when at a temperature 32^. In measuring this height, the lower extremity or zero point of the scale should be brought to coincide with the surface of the mercury in the cistern, by elevating or depressing the cistern by the screw beneath it, till the ivory zero point appears to meet its image reflected from the mercury (see Note a). The index should then be adjusted by turning the proper screw till the light is just excluded between the top of the mercurial column and the front and back lower edges of the index, when brought into apparent coincidence (Note b). The reading of the scale and vernier (Note c) will then indicate the observed height of the barometer, uncorrected for capillarity and index error. (1 a) In the barometers of Newman's construction the coincidence of the eero of the acale with the surface of the mercury in the cistern is effected by depressing or raising the whole scale itself, by a suitable screw. In those instruments whose scales and cisterns are both fixtures, the error in the position of the zero point must be allowed for by applying what is called the correction for capacity. (1 6) To assist the observation, a piece of white paper may be pasted on th« board, behind the top of the column. (1 e) The scale is graduated to inches, tenths, and half-tenths, i.e., to parts each •05 of an inch. The vernier is divided into five parts, each corresponding to 'OX of an inch, and these again into five parts, each corresponding to '002 of an inch. The scale reading is thus obtained. Case 1. If the prolongation of the zero line of th« Capillarity causes the mercury to stand lower in the tube than if capillarity did not exist; the correction for it is therefore additive. The index error is that arising from imperfect gradu- ation in the scale. A small table of the algebraical sum of the corrections for capillarity and index error should be suspended near the barometer, and the joint correction applied at the time of observation. The observed height of the barometric column must now be reduced to the temperature 32°, i.e., corrected for the expansion or contraction produced by changes of temperature on the mercury and scale. The temperature is ascertained by a ther- mometer attached to the barometer, and the proper correction from a table calculated for that purpose. Appendix Art. 54. In observing with the barometer, proceed as follows : 1. Lightly tap the tube, near the top of the column, to pre- vent adhesion of the mercury to the tube. 2. Read the thermometer. 3. Elevate or depress the cistern till the enclosed mercury just meets the ivory point. 4. Adjust the index. 5. Read the scale and vernier, and apply the joint correction for capillarity and index error. 6. Enter the result, together with the reading of the attached thermometer, in the proper columns of the reijister. The barometer should be placed in a room or passage subject to as little variation of temperature as possible, in a good light, but shaded from the sun. It should be fixed in a vertical posi- tion (Note d), and at such a height that the top of the scale vernier should coiocide with one of the lines of graduation of the scale, that line on the scale "will be the reading required. Case 2. If the zero line of the vernier, when produced, should not coincide with any line on the scale, that line on the Bcale which is next below the zero of the vernier must be read and taken as the approximate reading of the scale. That line on the vernier which most nearly forms a straight line with some line on the scale must then be read. The sum of the vernier reading and th'C approximate scale reading will be the complete scale reading. {Id) The verticality of the tube may be tested by turning it completely round, and noting whether the ivory point ^'us^ maintains coincidence with the siu-face of the mercury in tbe cistern during the whole revolution. This test should be repeated occasionally, and the verticality restored, if required, by the foot-screws. )e than erefore gradu- of the pended le time low be pansion on the a ther- ■rection 64. to pre- ury just rrection ittached subject d light, al posi- le scale that line le vernier, ne OD the cen as the ost nearly he sum of )lete scale ;ely round, surface of should be oot-8crew9. may be about on a leTcl with the eye of the observer. Its exa«t height above the ground, and if possible above the sea level, should be ascertained and recorded. Art. 2. — The Ordinary Thermometer. (See Note a.) The thermometer used for shewing the tempera- ture of the air should be entirely in the shade, and placed so as to be affected as little as possible by the heat of surrounding objects, but freely exposed to any existing currents of air. These conditions will be obtained if the instrument be fixed to a bracket on the north side of the house, from two to three feet from the wall, and with its bulb about three feet from the ground. It should be protected from above by an inclined roof, and on the north, east and west sides by lattice work, extending to about two feet below the bulb. The roof and lattice work should be painted white, to prevent the absorption of heat from external objects. It is desirable that the door by which the thermometer is approached should not communicate directly with the house, on account of the influence which heated air from the house would be likely to exert upon it. Should a position such as that just described be not attainable the following arrangement will serve : Select a window facing the north, in a room or passage, not heated, either on the ground floor, first floor, or staircase. At the distance of about ten inches from the window place a hori- zontal bracket for supporting the instrument. The thermometer should be protected from the weather as before described, the north side of the lattice work being about twenty inches from the window. The stem of the instrument should be perpendicular, and the middle of the scale about on a level with the observer's eye. In reading a thermometer it is essential that the eye be so placed that a straight line drawn from it to the top of the column of mercury may be perpendicular to the axis of the tube. With- out this precaution errors of observation may be committed even to the extent of one or two degrees. The observer should avoid (2 a) The reader is recommended to consult an article by Captain Lefroy, in the Canadian Journal, Sept. and Nov., 1852. 8 touching the thermometer, or breathing on it, or warming it by a too near approach of his person, and at night he should take care not to heat it with the reading lamp. If it be placed out- side a window the reading should be made without opening the window. The degrees must be read and the fractions estimated to tenths. Most thermometers, even good ones, if compared with an accurate standard, will be found to give a somewhat different reading from it, and the difference will not generally be the same throughout the scale. The difference is called the index error. It is marked + or — , according as the thermometer errs in excess or defect. A table giving the differences corres- ponding to different parts of the scale is called a table of index errors. The index correction is the index error with its sign changed. A table of index corrections should be kept at hand, and the corrections applied immediately after the observation (See Note b.) Art. 3. — Self- Registering Thermometers. These instruments are used for recording the maximum and minimum temperatures of the air that occur during my proposed interval of time, such, for instance, as the civi day. They should be placed in the same shed with the ord lary thermo- meter, but with their stems horizontal. (Appenc x Art. 57.) Art. 4. — The Maximum Thermon ter. When the mercury in this thermcneter for .s an unbroken column, which will be the case if its reading, ct "^cted for index error, agrees with a correct ordinary thermometer, the instru- ment is said to be set. If the temperature remains constant, or if it rises, the column will continue unbroken ; but if the tem- perature should fall, the mercury below the bend will retreat (2 b) In the original comparisons from which the table of index corrections is derived the differences are frequently marked with the signs that are proper to them as errors instead of as correctiont. As these original comparisons may be sometimes furnished to observers, they must be careful to make the distinction. All tables for correcting thermometers that arc furnished by the Director of the Magnetic Observatory are tables oi corrections. Tlie correction must be added to or subtracted from the observed reading of the thermometer, according as the correction is marked + or — . 9 into the bulb, leaving stationary the mercury above. The read- ing of the upper extremity of the column will then be the maximum temperature that has occurred during the interval commencing with the time of setting and ending with the time of reading. To set the instrument, hold it by the upper end, with the bulb downwards, and swing it with a moderate jerk till the continuity of thr column is restored. In doing this care must be taken to raise the temperature of the instrument as little as possible by the heat of the hand, as the temperature thus acquired will continue to be the reading of the instrument until it has been exceeded by the increasing tempevature of the air. Art. 5. — The Minimum Spirit Thermometer. When the column of spirit in the thermometer is unbroken, and the upper ends (or ends Farthest from the bulb) of the index and of the column of spirit coincide, the index is said to be set. Should the temperature descend, the column of spirit will con- tract, and draw the index with it. If the temperature should afterwards ascend the index will remain stationary while the spirit will expand beyond it. Hence while the maximum ther- mometer only shows the highest temperature that has occurred since the time that it was set, the minimum thermometer gives two indications. The uppe^ end of the column of spirits will, as in the case of an ordinary thermometer, shew the actual temperature at the time of observation, and the upper end of the index will give the lowest temperature that occurred since the index was set. T'> set the index, slightly raise the bulb till the index, aided if necessary by gentle tapping, slides to the top of the column (See Note a.) Art. 6. — In reading the self-registering thermometers the some precautions must be taken, as in the case of the ordinary ther- (6 a) If the column of spirit slioiild break, hold the instrument with the bulb downwards, and gently jerk the index down to the junction of the tube iiud the bulb; then hold the instrument nearly horizontal, but with the bulb slightly depressed, and jerk it in the direction of its length, and toward:^ the bulb, till the different portions of spirit become united. If the detached portions be much separated, the separation may be diminished by the careful application to the bulb of moderatelr warm water. It mometer, of placing the eye in a line drawn from the top of the column, and perpendicular to the axis. These instruments, like ordinary thermometers, are liable to be affected by index errors. These errors must be ascertained, so that the requisite corrections may be applied after each observation. Art. 7. — The Psychrometery or Wet-bulb Thermometer. The pressure of the atmosphere measured by the barometer, or the total pressure, is made up by the joint action of two pressures ; one, that of the atmospheric air, called the gaseous pressure; and another due to the presence of aqueous vapor, suspended in the air. The latter is called the elastic force of vapor, or simply the elasticity. The relative moisture of the air, or the humidity^ is the ratio of the actual mass of vapor contained in a given volume of air to the mass of vapor requisite to saturate that volume at the existing temperature. The values of the elasticity and humidity are deduced from the simultaneous readings of the ordinary dry-bulb thermometer and the wet-bulb thermometer, with the aid of hygrometrical tables, for an explanation of which see appendix, article 55. The latter instrument is an ordinary thermometer, with its bulb covered with thin muslin. The muslin is kept moist by means of a conducting thread of cotton wick (Note a), which connects it with a small vessel containing rain or distilled water, placed a little beneath it, and not too near the dry thermometer. The temperature indicated by the wet-bulb thermometer is called the temperature of evaporation ; it is always lower than that of the air, as shewn by the dry-bulb thermometer, owing to the heat lost by evaporation (Note b.) (7 a) The cotton wick, before use, should be washed in a solution of carbonate of soda, and it should be changed every two or three months. The muslin and the bulb ought to be occasionally washed, and the muslin renewed when defective. (7 b) Sometimes, in very foggy or damp weather, the wet-bulb has been found to read higher than the dry. This occurrence, however, is rare, and much doubt hangs over the explanation of it. Should it, however, happen at any station, and the observation seem in other respects reliable, it must be entered as a case of full saturation, attention being drawn to it in the returns by a special note. 11 If the temperature of the air be at or below 32®, the cistern and conducting thread become useless ; the bulbs must then be wetted by immersion (Notes c and d). A film of ice will then be formed, from which evaporation will proceed as before, and the thermometer will attain a stationary temperature lower than that of the air. The ice on the bulb, whenever its accumulation becomes excessive (Note e) should be melted off. It is advisable also to detach any drop of ice that may form beneath the bulb, as this might retain the temperature of the bulb near 32® and thu» overpower the effect of evaporation. In taking readings of the dry and wet- bulb thermometers, the dry should be first read, then the wet, and then the dry again, and if its reading should differ from its former one, the mean of the two should be set down for the adopted reading. The index correction of the wet-bulb thermometer should be applied after each observation. (7 c) This wetting is best effected by lifting up from beueath the bulb the vessel that contains the water. C? rf) Sonae authorities recommend that the observations should always be made by wetting the bulb, dispensing altogether with the cotton wick and reser- voir, and this probably is the surest way. Where this mode is adopted, some judgment is required in estimating the time that should be allowed to elapse, after wetting the bulb, before the observation is taken. Inordinary circumstances, 15 or 20 minutes will be sufficient, but when the air is much charged with moisture, and is calm, upwards of an hour may be necessary ; on the other hand, with a brisk wind and dry day, the thermometer may acquire its stationary temperature in two or three minutes, and great care is therefore required in determining whether the actual reading of the thermometer be that of evaporation. It is beet to watch the thermometer for half a minute after the observation has been taken ; if it show signs of falling the observation has been made too soon ; if of rising, too late, and the observation must be repeated. If the mercury remains stationary the reading may be accepted. (7 «) In the observation next following the formation of the film, care must be taken not to be deceived by a false minimum, which may be produced in conse- quence of the property which water possesses of falling several degrees below the freezing point without actually freezing. Thus on melting off the ice, the ther- mometer will first rise and then gradually sink, till it falls several degrees (it may be) below the freezing point The film Jhen freezes, and the thermometer rises to 32° ; it then begins to sink again, as evaporation proceeds, and ultimately attains its true temperature of evaporation. See remarks by Capt. Noble, R.A., Canadian- Journal, January, 1866. 12 Art. 8. — The Rain Gauge. Tlie rain gauge consists of a vessel of which the general form is that of an inverted cone, terminating in a small tube, which communicates with a receiver beneath. The upper orifice of the gauge is about 10 inches in diameter, and is guarded by a rim, sloping inwards, to prevent the rebound of the rain drops aa they fall on the interior conical surface. . The rain collected in the receiver is measured by a glass, graduated to cubic inches (Note a). If the volume of water expressed in cubic inches and tenths be divided by the area of the upper orifice, expressed in square inches and decimals, the quotient will give the depth that has fallen on the surface expressed in linear inches and decimals. To avoid the labor of performing this division, a table ha? been constructed, which is given in the appendix, art. 56. The rain gauge should be placed so that it may not be sheltered by trees or buildings, from rain descending obliquely. It should be enclosed in a box or cask, sunk to the level of the ground, with a lid having a circular aperture, just large enough to expose the orifice of the gauge (Note b). SECTION II. ON PHENOMENA OBSERVED WITHOUT THE AID OF INSTRUMENTS. Art. 9. — Wind. The direction of the wind is denoted by the point of the compass nearest to that from which the wind blows. In ordi- nary cases the direction may be expressed by the nearest of the eight principal points, but where great precision is required the nearest of the sixteen principal points must be employed. The names of the sixteen principal points, with the ordinary abbreviations are as follows, the eight principal points being printed in capitals : (8 a) If rain should be actually falling at the hour appointed for measuring it, the rain then in the receiver should be transferred to a jug, that the gauge and receiver may be restored to their places without loss of time. (8 b) To prevent the raiu that may fall on the lid or neighbouring ground from bounding into the gauge, a piece of old carpet or eome such eubstauce may be spread, i 18 NORTH. North-north-east. NOETH-EAST. East-north-east. N. N.N.E. . NE. E.N.E. EAST. East-south-east. SOUTH-EAST. South-south-east. E> E.S.E. S.lij. S.S.E. SOUTH. South-south-west. SOUTH-WEST. West-south-west. S. S.S.W. S.W. W.S.W. WEST. West north-west. NORTH-WEST. North-north-west. W. W.N.W. N.W. N.N.W. Art. 10. — The velocity of the wind must be estimated approximately, and expressed by numbers, according to the following scheme, in which it is to be remarked that the num- bers denote the order of magnitude of the velocities, but not their numerical values : 0. Calm or light air. 1. Very light breeze. 2. Moderate breeze. 3. Fresh breeze. 4. Strong breeze. 5. Moderate gale. 6. Fresh gale. 7. Strong gale. 8. Heavy gale, 9. Hurricane. 10. Very heavy hurricane. Art. 11. — Clouds. The nomenclature of the primary and secondary form of clouds is explained by two engravings, published by the Smith- sonian Institution, and of which a copy is bound up herewith. See Section III, Art. 29 Art. 12. — On Auroras, The classification of auroras to be employed (See Art. 13) is that adopted by the Smithsonian Institution, and which will be understood by the following remarks of Professor Olmsted, in the Smithsonian Contributions to Knowledge. The general directions in Art. 14, also used by the Smithsonian Institution, were principally adopted from those recommended by Captain Lefroy, when Director of the Toronto Observatory. The Aurora Borealis presents itself under six different forms : 1. Auroral Twilight. A light in the north, resembling the dawn of day, and of various degrees of intensity. 2. Arches. Arcs, or circles, or zones, formed at various altitudes, between N.E. and N.W., being sometimes the mere w 14 boundary of a segment, at other times a dense pillar of light, forming a grand columnar arch, which spans the heavens from east to west. It frequently moves from north to south, usually advancing but litiic fiirtlier than the zenith. 3. Streamers, Acuie cones or spindles, usually shooting up from an arch, or from a dark smoky cloud, which lies along the northern horizon, or rises a few degrees above it. 4. Corona. A circular zone around the pole of the dipping needle, formed of wreaths of auroral vapor, either of pure white or of various prismatic colors, with streamers radiating from the circumference. 5. Waves. Undulations which commonly flow upwards, to- wards the centre of the corona, along the line of the streamers, but sometimes course along the line of an arch, from east to west. 6. Auroral Clouds. A milky, vapory bank, in the north, the quantity and apparent depth of which afford a prognostic of the intensity of the approaching aurora. These clouds are some- times of a smoky hue, especially in front, while the margins are luminous. Art. 13. — We shall find it convenient to distribute the different forms of aurora into four distinct classes. Class I. This is characterised by the presence of at least three out of four of the most magnificent varieties of form, namely : arches, streamers, corona, and waves. The distinct formation of the corona is the most important characteristic of this class; yet, were the corona distinctly formed, without auroral arches or waves, or crimson vapor, it could not be con- sidered as an aurora of the first class. Class n. The combination of two or more of the leading characteristics of the first class, but wanting in others, would serve to mark the second. Thus the exhibition of arches and streamers, both of superior brilliancy, with a corona, while the waves and crimson columns were wanting, or of streamers with a corona, or of arches with a corona without streamers or columns (if such a case ever occurs), we should designate as an aurora of the second class. . u up the Glass III. The presence of only one of the more rare charac- teristics, either streamers or an arch, or irregular corruscations, but without the formation of a corona, and with but a moderate degree of intensity, would denote an aurora of the third class. Class IV. In this class we place the most ordinary form of the aurora, as a mere northern twilight, or a few streamers, with none of the characteristics that mark the grander exhibitions of the phenomenon. the least brm, ading should and the with rs or as an e Art. 14. — General Directions (Note a). 1. Make a regular practice of looking out for auroras every clear evening, from 8 to 10 o'clock or later. Record the result, whether there be an aurora or not. 2. Note the time of observation, and compare the watch used with a good clock, .is soon after as is convenient. 3. Make a return of the latitude and longitude of the station. 4. Note the class to which the auroral phenomenon belongs. 5. If it be an arch, note the time when the convex side reaches any remarkable stars, passes the zenith, disappears, &c. 6. If the arch be stationary for a time, mark its position among the stars on the map, so that its altitude may be deter- mined. 7. If it be a streamer or beam, mark its position on the map, and the time of its beginning and ending. 8. If motion be observed in the beams, note the direction, whether vertically or horizontally, to the east or west. 9. Note the time of the formation of a corona, and its position among the stars. 10. Note the time of the appearance of any black clouds in the north, near the aurora ; also if the sky be suddenly overcast with a mist at any time during the auroral display. 11. Give the /iirection and force of the wind at the time. 12. Note if any electrical effects are observed. 13. Note the effect upon a delicately suspended magnetic needle. (14 a) These directions may be considered as having reference principallj to the observations recorded in the extraordinary register. See Art. 41. 16 I ill Use of the Map (Note b). 1. To define the place and the extent of the aurora, the observer should familiarize himself with the relative position of the stars in the northern sky, by frequent inspection of the map, or a celestial globe. 2. Let the observer place the map before him, with the con- stellations in the positions in which they actually' appear at the time of the observation. This may be done by holding up a plumb-Une between the eye and the pole star, noticing the stars which it cuts ; then a light pencil drawn through these stars and the pole on the map will be the centre of the heavens, or place of the meridian at the moment. 3. Mark carefully the place among the stars of the arch of the aurora, and show its width by parallel curved lines. Make a note of the time. 4. Draw a light curved Hne, following, as nearly as can be judged, the outline of the arch drawn down to the horizon, on each side. 5. If the arch changes its position, mark its new place at intervals, noting the time of each observation. 6. Letter each position A, B, C, &c., and note the time and other particulars on the back or margin of the map, or in the register. 7. Beams or corruscations, or streamers of white or colored light, may be marked by lines at right angles to the above, with arrow heads pointing towards the place among the stars to which they tend, or where they would meet if prolonged. 8. To aid in the estimation of angular distances the spaces between certain conspicuous stars have been marked on the map, which will furnish a scale to assist the eye, when actual measurement may be impracticable. 9. The course of brilliant meteors, when they fall within the portion of the heavens included on the map, may be marked by a line, the length of which will show the path of the meteor ; the course should be indicated by an arrow, and the time recorded. (14 b) Copies of the map will be furnished to each station. 17 ira, the ition of I of the he con- r at the ng up a the stars stars and or place i arch of . Make s can be rizon, on place at ime and lor in the colored re, with to which le spaces d on the n actual ithin the larked by meteor ; the time Art. 15. — Atmospheric Optical Phenomena. Under this head are included many varieties of phenomena, such as peculiar or extraordinary coloring of the sky or clouds, excessive refraction or mirage^ diverging and converging beams, solar and lunar coronas, rainbows, haloes, parhelia and parse- lenes, and many others (Note a). SECTION III. METEOROLOGICAL REGISTERS. Art. 16. — The registers are four in number : (1.) The ordinary daily register book, (2.) The extraordinary register book. (3.) The book containing the monthly abstracts and yearly summary. (4.) The monthly, yearly, and occasional returns. AttT. 17. — The Ordinary Daily Register Book. This volume is for receiving the original entries of the ordinary observations at the time they are made, and is arranged for hold- ing the observationa of one complete year. It contains about 54 copies of a ruled form, marked (A,) about 14 copies of another form (B,) together with a few blank pages at the beginning and end of the volume. Art. 18. — Details. In the blank pages at the commencement should be written a table of contents and notices relative to each instrument. These notices should include — the name of the maker, the number or other mark, the date of its arrival at the station, the mode by which it was conveyed, the person from whom it was received,, the errors with which it is affected, the position in which it is placed, and mode of fixing it employed. If any change should be made in the position of an instrument, or any experiment made for testing its qualities, the date and occasion of such, change or experiment, with the several details, should be entered in the same part of the volume. (15 o) For details consult a paper by Professor Cherriraan, published in the Canadian Journal, August and September, 1852. B w Art. 19. — Form A. This form, which occupies one opening of two pages, is prepared to contain for one week the regular observations made at 7 a. m., 1 p. m., and 9 p. m. The several columns are to be filled up as follows : Art. 20. — In the column headed Barometer observed, enter the reading of the scale corrected for index correction and capillarity. In the column Temperature of Mercury, enter the reading of the therHiometcr attached to the barometer. From the table for correcting the observed height of the barometer for temperature, Appendix Art. 54, take out the requisite correction, and write it in small figures, with its proper sign, under the reading of the barometer observed. Apply the correction, and write the result in the column headed Barometer corrected to 32°. Art. 2l.'-Gaseous Pressure. The filling up of this column must be deferred till the completion of that for elasticity. Art. 22. — Temperature of the air observed. The column will contain the reading of the ordinary or dry-bulb thermome- ter. Beneath the actual reading write the index correction in small figures with its proper sign. Apply the correction, and write the result in the column headed Temperature of the air corrected. Art. 23. — The columns headed Observed and Corrected Wet' bulb Thermometer w'lW contain the actual reading of the wet-bulb thermometer, and that reading corrected for index error. Art. 24. — Difference of dry and wet-bulb. In this column is to be entered the excess of the corrected reading of the dry- bulb over the corrected reading of the wet-bulb. Art. 25. — In the columns for elasticity (e"), and humidity (!")» are to be written the elastic force of vapor, and the humidity obtained with the aid of the hygrometric tables, from the entries in the two preceding columns. (Appendix Art. 55.) Art. 26. — The elasticity (e") being known, the number to be entered in the column headed Gaseous Pressure will be found by subtracting the elasticity (e") from the total barometric pressure (b). in 19 pcning regular i, enter on and ading of of the out the s proper pply the irometer I column /• ; cohimn ermome- ection in lion, and f the air '.led Wet- wet-bulb * column the dry- tdi<2/(e")» lumidity \e entries )er to be )e found Lrometric Art. 27. — Direction of the wind. In this column enter that one of the eight principal points of the compass which is nearest to the point from which the wind was blowing at the hour of observation. Art. 28. — Velocity of the wind. The entry in this column must be made in conformity to the directions given in Section II., Art. 10. Art. 29. — Appearance of the aky^ fyc. This column is to contain a general description of liie state of the sky at the time of observation, including the class of clouds prevalent in different regions of the heavens. The names of the recognized forms of clouds, and the terma descriptive of their position may be expressed by the following abbreviations : for stratus. ** cumulus. IC st. cu. ci. •* cirrus. Nim. " Nimbus. ci-st. " cirro-stratus. cu-st. " cumulo-stratus, ci-cu." cirro-cumulus. o. for overcast. It. " light. " clear. cl. sp. Z. H. se. « space. " zenith. " horizon. V. ** distant objects distinct- scud, ly visible. Cloud symbols accompanied by a point of the compass, signify that the clouds referred to prevail in that quarter, and at an ele- vation varying from 30° to 60° above the horizon. The addition of Z. or H. denotes that the elevation is above 60° or under 30°. Z. or H. unaccompanied by any compass symbol, signifies that the clouds prevail close to the zenith, ot completely round the horizon. Finally, where two points of the compass are used, it must be understood that the clouds in question prevail from the point first expressed to the second quarter expressed, and reckoned in the direction of the motion of the hands of a watch. Example (1.) — Ci. Z.: cu. SW-NW. : st. H, would be read cirri prevalent in the zenith ; cumuli at an elevation between 30° and 60° in the western quarter, from south-west to north-west ; strati completely round the horizon. u 20 Example (2.) — 0. Dark Nim. save cl. sp. N. H., would be rend, sky overcast with dark nimbi, save some clear spaces in the north horizon. Art. 30. — Amount of cloudiness. In this column should be entered (to the nearest unit) the numerical value of the portion of the sky's surface that is clouded, the unit of surface being the tenth part of the whole hemisphere. (Not<* a.) Thus 10 will denote that the whole sky is covered with clouds. 6 " " half the sky is covered. 1 ** " one-tenth is covered. " •* the sky is quite clear of clouds. Art. 31. — Clouds in motion. In this column are to be entered the abbreviations or symbols for the class of clouds seen to be in motion. Their elevation may be expressed by the gene- ral terms, lofty, low, very lofty, and very low ; and their velocity by rapid, slow, very rapid, very slow, not perceptible. (Note a.) Art. 32. — Aurora, When the sky is clear, and no aurora is seen, this column should be entered with (o) ; if the existence of an aurora or its non-existence cannot be asserted in conse- quence of the presence of clouds, the entry should be (imp.) for impossible ; if finally an aurora is observed, the class, I. II. III. rV., to which it belongs, should be entered. (See Art. 13.) Art. 33. — General remarks. In this compartment a brief notice should be made of occasional phenomena occurring not only at the observation hours, but at any other hour of the day or night, such as thunder, lightning, hail, rain, snow, i<)g, dew, hoar-frost, sudden shifts of wind, atmospheric optical phenomena, together with any remarks that the observer may think useful, (30 a) The observer may be assisted in making this estimation by remembering that a portion of the surface of a sphere bounded by any circle is proportional to the versine of the angular distance of the circle from its pole. Thus, if the sky be clouded from the zenith downwards to a circle 30° above the horizon, or 60° from the zenith, since the versine of 60° is ^, half the sky will be clouded. (31 o) If there be more than one current as often happens, (especially preced- ing a storm,) the directions and character of each should be indicated separately in the compartment for remarks. 61 le ai fi P 21 lid be in the )u1d be lortion ing the clouds. to be ds seen le gene- velocity ^ote a.) urora is xistence I conse- np.) for II. in. 13.) a brief ring not the day >g» dew, nomena, : useful, nemberiog ortional to if the sky son, or 60° led. lly preced- geparately and for which he can find space (Note a). If any phenomenon mentioned in this compartment should be also described in the voluiTie of extra meteorological observations, the fact should be signified by the words, "see extra Met. Reg." (Note 6.) Art. 34. — Sums and Means. The columns of which the sums and means are to be taken are those headed, Barometer corrected to 32°, Gaseous Pressure^ Temperature of Air Corrected^ Wet-bulb Thermometer Corrected, Elasticity^ Humidity^ and Amount of Cloudiness. In calculating a mean, that is in dividing the sum of the individual terms by the number of tiicm, the division should be carried usually to one decimal place further than in the se])arate terms themselves. Thus the moans of the entries for the baro- meter and gaseous pressure should be entered to four decimal places ; the means of the temperature of the air and of the wet- bulb thermometer to two places, and the mean of the clouded sky to one place. The mean of the elasticity, however, is to be entered to the third place only, and the mean of the humidity to the nearest unit, saturation being expressed by 100. AiiT. 35. — Each page in Form B is designed to contain the observations of one month. Ttie self-registering thermometers are to be r^ad and again set each evening after the 9 p.m. observations, and their respec- tive readings entered as belonging to that day- (33 a) Amongst the many objects worthy of being noticed iu this compartment are periodical and occasional events, either meteorological, or dependent more or lees on meteorological conditions. Under the head of periodical events may be reckoned the last snow and frost in Bpj'ing, and the first frost and snow in autumn ; the beginiiiiig and end of the Indian summer; the opening and closing of harbors, rivers, and canals ; tlie first and last arrivals and departures of ships. Under the same cla?s may he placed — events in the vegetable kingdom, such as the leafing, flowering, maturity and fall of the leaf of certain plants, with the progress of agricultural operations; events in the animal kingdom, such as the movements of migratory animals. Under the head, occasional events, may be ranged, floods, droughts, and the pre- valence of different forms of disease. (33 6) If the requisite remarks, even in an abridged form, be too numerous to find room iu this compartment, the observer may enter them in the supplementary pages at the end of the volume, and notify that he has done so by referring to the page of the supplement. He should take cave also in the supplement to give the date to which the additional remarks belong. J m I i 22 In the columns maximum observed and minimum observed^ the actual readings of the instruments are to be entered. In the columns headed maximum corrected and minimum cor- rected, enter these readings corrected for index error. ( A.ppen- dix Art. 57.) Art. 36. — Rain began at and Rain ended at. Enter in these columns the hour and minute at which rain commenced and rain ceased to fall. If the rain should fall in frequent showers, the times at which the first shower began and the last ended should be entered, accompanied by the word " showers." Art. 37. — Total duration. This column will contain the aggregate duration of time that rain has been falling. The estimation of the duration will of course be only a rough approximation. Art. 38. — The quantity of rain that has fallen during the 24 hours is to be measured at 1 p m., and entered for the same day in the column headed cubic inches in guage. The volume may be expressed to the nearest tenth of a cubic inch. The corres- ponding depth obtained from the table (Appendix Art. 56) will be entered to the nearest thousandth of an inch in the following column. (Appendix Art. 57.) Art. 39. — Remarks similar to those recently made are appli- cable to the columns headed Snow began at. Snow ended aty and Total duration. The depth of snow must be estimated approximately and expressed in inches and tenths. (Appendix Art. 57.) Art. 40. — In ihe blank pages at the end of the volume may be written any supplementary remarks for which space could not be found in the compartment allotted for remarks in the daily register. All such entries should be accompanied by the day of the week and month to which they refer. EXTRA METEOROLOGICAL REGISTER. Art. 41. — In this book should be entered a detailed descrip- tion of any phenomenon whose occurrence was mentioned in the compartment Remarks of the ordinary daily register. It will contam also a record of readings of the barometer and other instruments, made at other times than the stated hours of bserved^ ed. In wn cor- A-ppen- in these find rain ers, ihe 1 should tain the The rough ; the 24 ime day ime may 3 corres- 56) will oUowing re appli- nded aty sstimated Lppcndix ;me may could not he daily le day of descrip- ed in the It will ind other hours of 23 observation, whenever such extra readings may he thought desirable. Art. 42. — As few observers will have leisure for making many extra observations, or for describing at any length the pheno- mena they witness, the following points are named as deserving special attention. The occasions when extra observations are most called for are during the occurrence of storms. By a storm is meant an exaggerated condition of any meteorological element, such as barometric pressure, temperature, wind, or an intense exhibition of an occasional phenomenon, as rain, snow, hail, &c. Thus we may speak of a thermic storm^ a barometric storm, a storm of wind, of rain, or of snow, a thunderstorm, and so forth. As regards the particular element which gives the distinctive name to the storm in question, the extra observations will be made with a view of discovering the following facts : The time and amount of maximum and minimum intensity, if temperature or barometric pressure be the elements concerned, together with the times when the changes, whether of increase or diminution, were most rapid. In a storm of wind notice the quarter from which the gale began, the point from which its violence was the greatest, and that from which its duration was longcjst, together with the hour and minute at which it began to blow from each of these quarters. Mention also the time of any sudden changes, and state in every case if the changes from one point to anorher were in the direction of the motion of the hands of a watch, or in the contrary direction. The times of greatest violence, and of sudden squalls and lulls, should be also recorded. In storms of rain or snow, notice the times of greatest intensity, as well as of sudden fall or sudden cessation. While the fluctuations of the element which gives the storm its name most need to be watched, attention must also be given to the simultaneous condition of other element?, as well as the times of their several changes. Thus, during a barometric storm, the state of the wind at the time of the maximum and minimum heijihts of the barometer, as well as the times at which the wind changes in direction and intensity, should be reconled. The thermometer should be also occasionally observed. These remarks are applicable to other storms, but it is to be noticed that as it is the wind that exercises most influence on the other elements, so it is the condition of the wind that deserves parti- cular watchfulness during every class of storm. This is true not only of surface winds, but of those that prevail in the upper strata of the atmosphere, and which are manifested by the moving clouds. In storms of wind the forms of clouds should be carefully noticed. Art. 43. — In the case of a thunder storm, the time when it began and ceased is to be mentioned, and the quarter whence it rose. The changes also of wind, with the form and motions of the clouds, and the time of occurrence (and if possible the quan- tity) of rain or hail should be noted. The state ot the barometer and thermometer ought also to be recorded from time to time during the progress of the storm. Art. 44. — Shooting Stars. These are most prevalent about the 10th and 11th of August, and between the 10th and 15th of November. The facts to be noticed relative to a shooting star, are the time and point relatively to the horizon in which it was first seen, the direction, length, and duration of its course, and its general appearance. If such precision cannot be attained, the total number seen by the observer, with the time and quarter of the heavens in which they seemed most' to abound* might be given. Art. 45. — The Monthly Abstract and Yearly Summary Book. This volume is to contain the abstracts of the observations of each of the twelve months formino; one vear, together with a comparative table or summary of the whole. The headings of the several columns will for the most part explain the proper mode of fillhig them up. It will be understood that the num- bers to be entered are corrected results, and that the uncorrected entries of the daily register are not to be inserted. The yearly summary contains the monthly means of each meteorological element, together with the hourly means for each month. It contains also the number of times in each month 25 aoticcd that certain phenomena occurred, together with the dates of ' other such periodical events as occur but once each year. i parti- rue not upper by the arefuUy vhen it lence it lions of le quan- rometer to time it about 15th of ing star, I it was rse, and attained, ime and abound) y Book. ations of r with a adings of e proper he num- corrected I of each s for each :h month Art. 46. — Periodical Returns. The periodical returns are copies of the monthly abstracts and yearly summary made upon loose forms, similar to those bound up in the abstract books. The return for January should be accompanied by a sheet of paper containing a copy of the notices relative to the instruments, as entered in the introduction to the daily register. Whenever any change is made and recorded in the same introduction, the flict should be notified in the return of the month wherein the change referred to took place. The mcmthly reports should be transmitted punctually to the Chief Superintendent of Education as required by law. Art. 47. — Occasional Returns. These are copies or abridged copies of the observations entered in the extraordinary register book. Those relating to violent storms of wind or rain should be forwarded as soon as possible after the time of the occurrence of the storm. Art. 48. — General Remarks. It is verv desirable that the entries of the observations should be corrected, and the hygrometric quantities taken out of the tables and entered immediately after the observation has been completed. It is recommended that each calculation be per- formed twice. To do this, It will be a good arrangement for the observer each mornino; to examine the enl'-ies and corrections of the preceding da}', and calculate the means. The same means should be examined later in the day and marked as " examined.'''* Art. 49. — All copies of records should be compared with their originals by two persons, one of whom should read the figures aloud. Art. 50. — It is of great importance that unifornnty of nota- tion be preserved ; observers, therefore, arc requested to attend to the foilowinnj rules : I. The sign minus ( — ) should be always placed on the left of the number to which it refers, and never in any other posi- / / tion ; thus, if the temperature be 10°. 5 below zero, it should be written — 10°. 5, and never 10°. 5 — or what is worse ^^ 2. Vulgar fractions are never to be u?ed, but decimal fractions only; thus, ten and a half degrees should be written 10°. 5, and not 10^°. Art. 51. — The observer, in making up his periodical or occa- sional returns, should be careful not to omit the filling up of the heading. The omission of his name, and of the latitude and longitude of his station, may cause confusion when two stations happen to be similarly named. Art. 52 — It is also particularly requested that, if an observa- tion should be accidentally omitted, no attempt be made to fill up the blank by conjecture ; neither should the observer permit himself to deviate in the slightest degree from entering strictly what he actually observes, however unlikely the observation may seem. The best chance of discovering the cause of an anomaly lies in the same being rigidly recorded, and a few blanks in the columns are of less importance than the detection therein of a conjectural emendation, which would vitiate the whole series by destroying its trustworthiness. Art, 63. — Synopsis of Daily Routine of Observation. Hours: 7 a.m. ; 1 p.m. ; 9 p.m. I. Barometer. 1. Gently tap the tube. (Sec. 1, Art. 1.) 2. Read the attached thermometer. 3. Adjust the cistern. 4. Adjust the index. 5. Read the scale and vernier. n. Read the dry-bulb thermometer. (Sec. I, Art. 2.) III. Read the wet-bulb thermomeier. (Sec. I, Art. 7.) IV. Repeat the reading of the dry-bulb. V. Note the direction and velocity of the wind (Sec. II, Art. 9, 10); the amotuit of cloudiness (Art. 11); the general appearance of the sky (Sec. Ill, Art. 27-31), including the class, distribution, and motion of the clouds, with the state of the weather generally. it should e -^ ^ IU».6. fractions • °.5, and or occa- up of the itude and stations 1 observa- ide to fill rer permit ig strictly bservation luse of an md a few detection vitiate the vation. \.rt. 1.) 2.) 7.) . 11, Art. 9, the general ), including ds, with the f 27 Additional. At 1 p.m. measure the rain (Sec. I, Art. 8 ; Sec. Ill, Arts. 36-38.) At 9 p.m. read the maximum and minimum thermometers^ and re-set them (Sec. I, Arts. 4, 6). APPENDIX. Remarks relative to the tables referred to in the preceding pages. Art. 54. — Table I. for reducing the observed reading of the Barometer to the temperature 32°. The corrections for temperatures from 0° to 100° is con- tained in Table I. Should the temperature of the mercury of the barometer fall below zero, the proper correction may be derived with sufficient accuracy from the upper row of numbers in the table, by adding .0025 for each negative degree of temperature. Art. 55. — The tables to be used for finding the elastic force of vapor and humidity, from the simultaneoiis reading of the dry and wet-bulb thermometers, are those prepared by Professor Coffin, from the formulae of Regnault. Professor Coffin has calculated the tables on the supposition that the height of the barometer is 29.725 inches ; now, as the reading of the baro- meter will often di^er greatly from this assumed standard, it will be generally necessary to apply to the elasticity a correction depending on the height of the barometer. Tables II and III have been calculated for the purpose of supplying this correction ; II when the temperature of the wet- bulb thermometer is above 32°, and III when that temperature is 32° and under. (53 a) The rearlinf^s of the instruments may, at the instant of observation, bft mtetl down in a pocket book, or slip of paper, but thsy should be transferred to the register book immediately after the completion of the observation. 28 iiili The correction is to be added to the elasticity (e") when the reading of the baroinoter is below the standard for which the hygrometrical tables are calculated (2.725 in the present case),, and to be subtracted from it when the reading, is above the same standard. The table of corrections will serve for any other hygrometric tables calculated from the same formula^ and in which another standard h' is used, by adding h' — 29.725 to the numbers in the second and third columns. Art. 56.— Tables IV, V, VI, VII and VIII give the depth corresponding to any number of cubic inches of rain received in a gauge with a circular mouth. The diameter of the guages, from unavoidable errors in work- manship, will frequently differ slightly from any assun>ed stan- dard ; on this account five different tables have been constructed, from which the observer must select that one to which his own I i 'Mil I (56 a) If the diameter of thtf gauge should materially differ from those foi* ■which the tables are ciilcuhited, the observer had better calculate a table for himself in the following manner : Area of a circle (diameter c?) = ir (^)» where »=>= 3.1415926. Hence depth corresponding to 1 cubic inch received in the gauge = ■nit ^2 d\2 4 but ^ = 1.273239 and d* = 102,01, if ed stan- istnicted, his own jrauge most nearly corresponds, within the limits 10.1 and 9.9 inches. The mode of using these tables will be at once under- stood from the following examples : Examples in the use of Table IV : Required, the depths to three decimal places, when the volumes of rain received in the gauge measured respectively (1) 5 cubic inches, (2) 0.8 cubic inches, (3) 7.3 cubic inches. Ans. (1) .062 inches, (2) .010 inches, (3) .091 inches. Example 4. Required, the depth to three decimal places, when the volume of rain was 45.4 cubic inches. .Depth for 10 cubic inches = .1248 4 <( a (( (( 40 cubic inches 5.4 cubic inches .4992 .0674 Depth for 45.4 cubic inches = .567 inches. Ans. bicb form the ; the decimal completed by libers in the o four places ces. such as that places. t refercuce. to his guage cor- *-wt I iwi .•*<■< tr II! f / '^ ^ ^ii i 80 TABLE I. Corrections to be applied to the readings of Barometers with Braaa SeaUa extending from the Cistern to the top of the Mercurial Cohimn, to i educe the observations to 82^. The correction is to be added for Temperatures 28o and under, and to be subtracted for Temperatures 29° and upwards. • INOHES. A i 28 28.6 29 29.5 80 80. » 81 0° + .072 + .073 + .074 + .076 + .077 + .078 + .080 0° 1 069 071 072 073 074 076 077 1 2 067 068 069 070 072 073 074 2 8 064 065 067 068 069 070 071 3 4 062 063 064 066 066 067 068 4 6 059 060 061 062 068 066 066 5 6 057 058 059 060 061 062 063 6 7 064 065 056 057 058 059 060 7 8 052 053 054 054 065 056 057 8 9 049 060 061 062 053 054 054 9 10 047 047 048 049 050 051 052 10 11 044 046 046 046 047 048 049 11 12 042 042 043 044 045 045 046 12 13 039 040 040 041 042 043 043 13 U 087 037 ' 038 088 039 040 040 14 15 034 035 035 036 036 037 038 16 16 032 032 033 033 034 034 035 16 m 029 030 030 031 031 032 032 17 18 026 027 027 028 028 029 029 18 19 024 024 025 025 026 026 027 19 20 021 022 022 023 023 023 024 20 21 019 019 020 020 020 021 021 21 22 016 017 017 017 018 018 018 22 23 014 014 014 015 016 015 016 28 24 Oil 012 012 012 012 012 013 24 26 009 009 009 009 009 010 010 25 26 006 006 007 007 007 007 007 26 27 004 004 004 004 004 004 004 27 28 001 001 001 001 001 001 001 28 29 — .001 — .001 — .001 — .001 —.001 —.001 —.001 29 80 004 004 004 004 004 004 004 30 81 006 (106 007 007 007 007 007 31 82 009 009 009 009 009 010 OlO 32 83 Oil 012 012 012 012 012 012 33 84 014 014 0)4 015 015 • 015 015 84 85 016 017 017 017 018 018 018 36 86 019 019 020 020 020 021 021 86 87 021 022 022 022 023 023 024 37 88 024 024 025 025 026 026 026 38 49 026 027 027 028 028 029 029 39 40 029 029 030 030 031 081 032 40 41 0:U 032 033 033 034 034 035 41 42 034 034 035 036 036 037 037 42 43 036 037 038 038 039 040 040 43 44 039 040 040 041 042 042 043 44 45 041 042 043 044 044 045 046 45 K'rv rasa Scales I, to 1 educe mperatiires upwards. ^**"* 9SSS h 3 1 H 80 0° 77 I 174 2 (71 S )68 4 \ 5 6 7 8 » 10 11 12 18 14 16 16 17 18 19 20 21 22 28 24 26 26 27 28 29 30 31 32 83 84 36 86 37 38 39 40 41 42 43 44 46 TABLE h— (Concluded.) • INCHES. fis s 28 28.6 29 29.6 30 80.6 81 1 •* 46 • -.044 - -.046 - -.045 - -.046 . -.047 . -.048 - -.049 46 47 046 047 048 049 050 051 051 47 48 049 060 051 062 062 053 054 48 49 051 062 053 054 056 056 067 49 60 064 056 066 057 058 059 060 60 61 056 057 058 059 060 061 062 61 52 059 060 061 062 063 064 065 62 63 061 063 064 065 066 067 068 63 64 064 065 066 067 068 070 071 54 66 066 068 069 070 071 072 078 55 56 069 070 071 073 074 076 076 56 57 071 073 074 075 076 078 079 57 58 074 075 077 078 079 081 082 58 59 076 078 079 080 082 083 085 59 60 079 080 082 083 086 1 086 087 60 61 081 083 084 086 087 089 090 61 62 084 085 087 088 090 091 093 62 68 086 088 089 091 093 094 096 63 64 089 090 092 094 095 097 098 64 65 091 093 095 096 098 100 101 65 66 094 096 097 099 101 102 104 66 67 096 098 100 102 103 106 107 67 68 099 101 102 104 106 108 109 68 69 101 103 106 107 109 110 112 69 70 104 106 108 109 111 113 115 70 71 106 108 110 112 114 116 118 71 72 109 111 118 115 117 119 120 72 78 111 118 115 117 119 121 123 78 U 114 116 118 120 122 124 126 74 75 116 118 120 122 125 127 129 76 76 119 121 123 125 127 129 131 76 77 121 123 126 128 180 132 134 77 78 124 126 128 130 133 135 137 78 79 126 128 131 1S3 135 137 140 79 80 129 131 133 136 138 140 143 80 81 131 134 136 138 141 143 145 81 82 134 136 138 141 143 146 148 82 83 136 139 141 143 146 148 161 88 84 139 141 144 146 149 151 154 84 85 141 144 146 149 151 154 156 86 86 144 146 149 151 154 156 159 86 87 146 149 151 154 157 159 162 87 88 149 151 154 157 159 162 165 88 89 151 154 156 159 162 165 167 89 90 153 156 159 162 164 167 170 90 91 156 159 162 165 167 170 173 91 92 158 161 164 167 170 172 175 92 93 161 164 167 170 172 175 178 98 94 163 166 169 172 175 177 180 94 96 166 169 172 175 178 180 183 95 96 168 171 i'/4 178 181 183 186 96 97 171 174 177 180 183 186 189 97 98 173 176 179 ■ 188 186 188 191 98 99 176 179 182 185 188 191 194 99 100 178 181 184 188 191 194 197 100 iiiii TABLE Corrections to be applid to e" for the Height of the Bar The Corrections are to be added or subtracted accord The Corrections are given BAROMETER. DIFFERENCE OF THE DRY AND Difference from Standard. Height Height 3 1.0 * 2.0 .002 3.0 .003 4.0 .004 5.0 .004 o 6.0 .005 o 7.0 .006 <> 8.0 .007 9.0 .008 10.0 .009 11.0 2.0 in. 31.725 in. 27.725 .001 .010 1.8 31.525 27.925 001 002 002 003 004 005 006 006 007 008 009 1.6 31.325 28.125 001 001 002 003 004 004 005 006 006 007 008 1.4 31.125 28.825 001 001 002 002 003 004 00-1 006 006 006 007 1.2 30.925 28.625 001 001 002 002 003 003 004 004 005 005 006 1.0 30.725 28.725 • • 001 001 002 002 003 00? 004 004 004 006 0.8 30.525 28.925 • • 001 001 001 002 002 002 003 093 004 004 0.6 30.325 29.125 • • 001 co; 001 001 002 002 002 002 003 003 0.4 30.125 29.325 001 001 001 001 1 001 001 002 002 oo:. 0.2 29.925 29.525 • • « • • • 001 001 001 001 001 001 I ! Hi: i"' Id I' II! ABLE ){ the Bar ted accord are given DRY AND .0 i08 107 (06 )06 )05 10.0 11.0 ,009 008 007 006 005 010 009 008 007 006 )04 004 005 J03 004 004 )02 003 003 W2 002 oo:. 001 001 001 33 II. ometer, the Thermometer being above 32® Fahrenheit, ing as the height is less or greater than 29.725 inches, in decimals of an inch. WET THERMOMETERS IN FAHRENHEIT'S SCALE. o 12.0 18.0 14.0 o 15.0 16.0 o 17.0 o ~ 18.0 19.0 o 20.0 21.0 o 22.0 23.0 24.0 o 26.0 o 26.0 .011 .012 .012 .013 .014 .015 .016 .017 .018 .019 .020 .020 .021 .022 .023 010 010 Oil 012 013 014 014 016 016 017 018 018 019 020 021 009 009 010 Oil Oil 012 013 014 014 015 016 016 017 018 018 007 008 009 009 010 Oil Oil 012 012 013 014 014 015 C16 016 006 007 007 008 009 009 010 010 Oil Oil 012 012 013 013 014 006 006 006 007 007 008 008 008 009 009 010 010 Oil Oil 012 004 006 006 006 006 006 006 007 007 007 008 008 009 009 009 003 003 004 004 004 005 006 006 005 006 006 006 006 007 007 002 002 002 003 003 003 003 003 004 004 004 004 004 004 006 001 001 001 001 001 001 002 002 002 002 002 002 002 002 002 kP^^^^ ^^^^^9^ ^>;^yf S 8 eo 8 01 — 8 8 © © at 00 8 8 «o CO 8 8 8 00 8 8 «o lO lO o © 8 ^ CO Ol 1— 8 § 00 00 o © 8 8 00 CO 8 8 8 8 00 © © © © to © © to 8 CO 04 © © o g (N 1— 8 8 <0 lO 8 8 8 8 CO »i 8 8 8 lO lO 8 8 CO 8 01 01 8 8 © © to 8 to CO CO 8 8 8 8 to CO CO e» 8 8 8 8 8 CO CO 8 8 CO 8 8 CI l-H 8 8 8 CO e» CO (N £_8 "n ST o» 01 ff« 8 8 o © © © Vi f^ W-* ft r-l (N 1-4 to to to IS o> t-« (N f-* f^ 1-4 (-4 O lO to 04 01 a* a> e« 9* to to ©4 ©1 CO t>« « .S CO CO 00 CO 03 00 ©) CO OO 00 CO 00 ^ rH ^ ^ 1-1 O c © o © © © lO ©« OS to ©1 at ©1 i 001 ; § I § I 1 i 001 G1 w^ s 8 ^H ^4 s o l-H ^ 8 8 i-< ^^ r> o o o 1-^ 8 1-^ 8 ^^ • 1 o • 1 © • '. I • • • • • • • • • • • • • lO la OS (?1 0* lO )0 (N ©1 W o> • o o> CO (M '«1< ©J • > o o Tablep for finding the depth to the Oiousandth part of an inch, corresponding to (n) cubic inches of rain received in a circular guage, the diameter of whose aperture =» d. The Tables are calculated for rf*=10.1 in., 10.06 in., 10 in., 9.96 in. and 9.9 itj., from the formula '•^p"'"^."-* rf» TABLE IV. Diameter of aperture = 10.1. is TENTHS or A OUBIO INCH. ■ 1 ii .0 .1 .2 .3 .4 .6 .6 .7 .8 .9 .0000 .0012 .0026 .0087 .0060 .0062 .0078 .0087 .0100 .0112 1 0126 0187 0160 0162 0176 0187 0200 0212 0226 0237 2 0260 0262 0276 0287 0300 0812 0826 0837 0849 0862 8 0374 0387 0899 0412 0424 0437 0449 0462 0474 0487 4 0499 0612 0624 0687 0649 0662 0674 0687 0699 0612 6 0624 0637 0649 0662 0674 0687 0699 0711 0724 0786 A 0749 0761 0774 0786 0799 0811 0824 0886 0849 0661 1 0874 0886 0899 0911 0924 0936 0949 0961 0974 0986 8 0999 1011 1024 1086 1048 1061 1078 1086 1098 nil 9 1128 1186 1148 1161 1178 1186 1198 1211 1223 1236 10 1248 1261 1278 1286 1298 1811 1828 1886 1348 1361 TABLE V. Diameter of aperture == 10.06. TENTHS or A CUBIC INCH. .0 .1 .2 .8 .4 .6 .6 •^ .8 .9 .0000 .0018 .0026 .0088 .0060 .0063 .0076 .0088 .0101 .0113 1 0126 0189 0161 0164 0176 0189 0202 0214 0227 0240 2 0262 0266 0277 0290 0303 0316 0828 0840 0868 0366 8 0378 0891 0408 0416 0429 0441 0464 0466 0479 0492 4 0504 0517 0529 0642 0566 0567 0680 0692 0606 0618 6 0630 0643 0666 0668 0681 0693 0706 0719 0731 0744 6 0756 0769 0782 0794 0807 0819 0832 0846 0867 0870 7 0882 0896 0908 0920 0983 0946 0968 0971 0983 0996 8 1088 1021 1084 1046 1069 1072 1084 1097 1109 1122 9 1136 1147 1160 1172 1186 1198 1210 1228 1236 1248 10 1261 1273 1286 1298 1811 1824 1836 1349 1361 1874 '♦ ..■ iill Imi I 36 TABLE VI. Diameter of Aperture 10. ^i TENTHS OF A COBIC INCH. n n .0 .1 .2 .8 .4 .6 .6 .7 .8 .9 .0000 .0018 .0025 .0038 .0061 .0064 .0076 .0089 .0102 .0116 1 0127 0140 0158 0166 0178 0191 0204 0216 0229 0242 2 026D 0267 0280 0298 0806 0318 0331 0344 0357 0869 8 0382 0896 0407 0420 0433 0446 0468 0471 0484 0497 4 0509 0522 0635 0547 0660 0673 9586 0598 0611 0624 5 0687 0649 0662 0675 0688 0700 0718 0726 0738 0751 6 0764 0777 0789 0802 9815 0828 0840 0858 0866 0879 1 0891 0904 0917 0929 0942 0956 0968 0980 0998 1006 8 1019 1081 1044 1067 1069 1082 1096 1108 1120 1138 9 1146 1159 1171 1184 1197 1210 1222 1235 1248 1260 10 1278 1286 1299 1811 1824 1337 1360 1362 1375 1388 TABLE VII. Diameter of Aperture 9.95. si TBMTHS OF A CUBIC INCH. 8g .0 .1 .2 .8 .4 .6 .6 .7 .8 .9 .0000 .0018 .0026 .0039 .0051 .0064 .0077 .0090 .0108 .0116 1 0129 0141 0154 0167 0180 0193 0206 0219 0282 0244 2 0257 0270 0288 0296 0809 0322 0884 0347 0360 0378 3 0386 0399 0412 0424 0487 0450 0463 0476 0489 0602 4 0514 0627 054O 0658 0566 0579 0592 0604 0617 0680 6 0643 0656 0669 0682 0694 0707 0720 0733 0746 0769 6 0772 0785 0797 0810 0828 0836 0849 0862 0875 0887 7 0900 0913 0926 0939 0962 0965 0977 0990 1003 lOld 8 1029 1042 1065 1067 1080 1093 1106 1119 1132 1146 9 1157 1170 1188 1196 1209 1222 1235 1248 1260 1273 10 1286 1299 1812 1825 1888 1350 1363 1376 1389 1402 tei bu to th or rei pa Sii tbi in as se: .8 .9 102 .0115 229 0242 351 0369 484 0497 611 0624 738 0751 866 0879 993 1006 120 1138 248 1260 375 1388 .8 .9 )10S .0116 )232 0244 )360 0378 )489 0502 )617 0630 )746 0769 3876 0887 1003 loie 1132 1145 1260 1273 1389 1402 37 TABLE VIII. Diameter of Aperture 9.9. a3 TKNTHS OF A CUBIC INCH. n n .0 .1 .2 .3 .4 .5 .6 .7 .8 .9 .0000 .0013 .0026 .0039 .0052 .0065 .0078 .0091 .0104 .0117 1 0130 0143 0156 ()169 0182 0195 0208 0221 0234 (i'J47 2 0960 0272 0286 0299 0812 0325 0338 0351 0364 (*;:77 3 0390 0403 0416 0429 0442 0455 0468 0481 0494 or, 07 4 0520 0583 0546 0559 0572 0585 0598 0611 1 0ti'.'4 (i«)H7 5 0650 0663 0676 0689 0702 0715 0728 0740 07rj3 OTf.rt 6 0779 0792 0805 0818 0831 0844 0857 0870 0883 iisyc. 7 0909 0922 0935 0948 0961 0974 0987 1000 1013 11)26 8 1039 1052 1065 1078 1091 1104 1117 1130 1143 ijr.6 9 1169 1182 1195 1208 1221 1234 1247 1260 1273 r.'86 10 1299 1312 1325 1838 1351 1864 1877 1390 1403 1-116 Art. 57. — Additional Notes. {Note to Art. 3.") To prevent the detached mercury of the maximum thermome- ter from sliding beyond the maximum point, which will Bometimes happen if the bulb end of the tube be raised too high, it will be safe to give a slight inclination to the tube, the bulb end being the lo^er. (Notes to Arts. 29, 31, 46, 46.J In the columns of the monthly abstracts headed " clouds," and " clouds in motion," it will be sufficient to enter a selection only from the entries of the corresponding columns of the daily register. {Note to Art. 82.) If the observer be doubtful whether an aurora was observed or not, this doubt may be expressed by a note of interrogation. (?) {Notes to Arts. 85, 36, 37, 38, 39.) If the self-registering thermometers be not read and re-set on Sunday night, the readings on Monday night should be accom- panied, in the column of remarks, by the entry " max'm of 48*- and rain'm of 48*-" Similarly the depth of rain measured on Monday at 1 p. m., must be entered as that of 48 hours, unless it be certain that it fell on one of the two days only. The Sunday entries for the columns headed " rain began at,"