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Un des symboles suivants apparaltra sur la dernl*re image de cheque microfiche, selon Ie cas: Ie symbols — »• signifie "A SUIVRE", Ie symbols y signifie "FIN". Maps, plates, charts, etc., may be filmed at different reduction ratios. Those too large to be entirely included in one exposure are filmed beginning in the upper left hand corner, left to right and top to bottom, as many frames aa required. The following diagrams illustrate the method: Les cartes, planches, tableaux, etc., peuvent *tre film*s * des taux de r*duction diff*rents. Lorsque Ie document est trop grand pour *tre reproduit en un seul ciich*. 11 est film* * partir de Tangle sup*rieur gauche, de gauche * droite, et de haut en bas, en prenant Ie nombre d'imeges n*cessaire. Les diagrammee suivants illustrent la m*thode. 1 2 3 1 2 3 4 5 6 y^ ' "'^^'X REPORT i).V TIIK METEOROLOGY OF TORONTO: HY LIEUT.-COL. EDWARD SABINE, R.A., F.R.S. {l^rnm tho Repokt of thk Buitish Association for the Advancement oi^ SciENCu/or 1844.] LONDON: I'UIMI'.I) IIV HICIIAIU) AND JOHN V. lAVL')!!, HiiD I. ION coriiT, fleet HTRKKT. 181. 3. J [A communis The subjei tion of the at the ma< the first tw the Sectio Associatioi parts of th observatioi duction an conduct of communici such of th( sions to \vl members. of the resu 1842, hav( fully exan servations generally, observatio fullness nc of in this year, exce the period On the Meteorology of Toronto in Canada. By Lieut.-Colonel Edward Sabine^ R.A., F.R.S, [A communication made to the Mathematical and Physical Section at the York Meeting, and directed to be printed entire amongst the Reports.] The subject which I am about to bring before the Section consists of a por- tion of the results of the meteorological observations which have been made at the magnetical and meteorological observatory at Toronto in Canada, in the first two years of its establishment. It is well known to the members of the Section, that in conformity with the recommendation made by this Association, the British Government has formed establibhments in various parts of the globe, for the purpose of making magnetical and meteorological observations on a systematic plan, and has created a department for the re- duction and publication of the observations. As the officer entrusted with the conduct of these operations, I regard it as not less a duty than a pleasure, to communicate, from time to time, at the meetings of the British Association, such of the arrangements, or of the observations themselves, or of the conclu- sions to which they may have led, as I may suppose may be interesting to its members. I have accordingly selected for the present occasion some portion of the results which the meteorological observations at Toronto, in IS-tl and 1842, have yielded, when subjected to a full process of reduction, and care- fully examined. I have preferred the meteorological to the magnetical ob- servations, partly on account of the more popular character of the subject generally, and partly because the conclusions to which the meteorological observations have already conducted appear to possess a completeness and fullness not yet attained in magnetism. The observations, which will be treated of in this communication, were made at every second hour throughout the year, except on Sundays, Christmas day, and Good Friday. Subsequently to the period which will be now passed in review, they have been made hourly, REPORT — 1844. and the results of these may possibly be brought before the Section on a future occasion. For tiie purpose of rendering this communication more interesting and more useful, I have compared the meteorological results obtained at Toronto with those obtained by M. Kreil at the magnetical and meteorological obser- vatory at Prague in Bohemia*. It is frequently found that we gain more by such comparisons, — by the jjoints of resemblance and points of difference, and by the analogies and contrasts which they bring to our notice, — than we do by a simple din ct investigation. Prague like Toronto is situated at a considerable distance from the ocean (between 300 and lOO miles) in tlie interior of a great continent, the latitude and elevation moreover not being very dissimilar. The agreement which will be shown in the leading features of their meteorology manifests that these features belong to a locality so circumstanced, whether the continent be Europe or America ; whilst the minor dlH'erences point to clinuitological distinctions of a secondary oider, im]K)rtant indeed to discuss from their bearing on the health and occupations of mankind, as well as in more purely scientific respects, but into which time will scarcely permit me to enter on the present occasion beyond a mere notice of some of the facts. In all compjrisons between places situated in Europe and in North Ame- rica, tiiere is one leading difference in respect to temperature which we must expect to find, whieii is doubtless familiar to all the mendjers of the Section, viz. tiiat in Euro|)e we enjoy a climate of higher mean temperature in pro- portion to the latitud(' tlian is the case in America; in other words, that the isothermal lines descend into a lower latitude in America than they do in Europe. It would occupy far too much time to discuss, on the present occa- sion, the causes of this great climatological difference ; they have been largely discussed by many eminent plulosophers ; but it may be well, before we pro- ceed to further details, to notice briefly the amount of difference in this re- spect whieli is shown by the observations at Prague and Toronto. The following statement exhibits the particulars of the latitude, elevation above the sea, and mean temperature of the two stations ; as well as the cor- rection of the difference of their mean temperatures on account of difference of elevation : — Toronto, latitude 4-3° 39' Elevation 330 feet. Prague, „ 50 05 „ 582 „ Difference G 26 Difference 252 Prague should be colder on account of its elevation . ()°*8 Fahr. Mean te-mperature, Toronto 44°'4 1 t^.,,. , „ Prague . 48 •? t / ^'««r^"«^ ' ' ' '^ Difference of temperature eorrected 1 ,, _ , ,. I-,.' .' 1 ..• ) 1 ratrue wanner a 'i \ov difh'rence of (4evation J *^ Whence it apjjcars that Prague is 5°*1 warmer than Toronto, although its latitude is ()^2G' n\ore distant from the equator. TKMPKRATURK. We will now proceed to the distribution of the mean temperature into the several hours ol' the day, and into the several niontiis of the ycuir ; the first, forming the dinnml variation of the tt.'mpc ratnre, or that variation which has a (1(11/ for its i)eriod ; tin; sc cond, the anniml variation, or that variation which has (( i/('(ir for its ])erio(l. DiiiriKil \'((ritttioii. — The diurnal variation is the well-known consequence * Mng. uiiil Mm. llcohiuliC'M-cii ; Pnis. 1H3!)-1842. f Kreil, Jahrliucli fur IHia. i i I I of the ear| ascending early in tj each yeal being onj Each hoi servation^ the days perature amount (1 ral hoursl mined til by two hi d flHll. = I HI-- ^ ! Mean ON THE METEOROLOGY OF TORONTO IN CANADA. I I i of the earth's rotation on its axis. It is a single progression ; having but one ascending and one descending brancii, the turning points being a maximum early in the afternoon, and a minimum about sunrise. Each hourly mean in each year in the subjoined table is an average of about 31 1 observations, being one on each day, except Sundays, Good Friday and Christmas day. Each iiourly mean of the two years is therefore an average of about 622 ob- servation?:. The mean temperature of each year, or of all the hours on all the days of the year, rests on about 3732 observations ; and the mean tem- perature of the two years on about 7164' observations. The very small amount of tlie differences which the table exhibits in the results at the seve- ral hours in 1841 and 184'^, shows a probability that we have already deter- mined tlie diurnal march of the temperature, (as far as it can be obtained by two liourly observations,) with a very near approximation to the truth*. Mean Annual Temperature at every observation hour f) A . M I ^ A . M . 10a.m. Noon . 2 p . M . I r . M . () p . M . 8 p . M . I 1 p . M . d (-1811., = I ISlv!., .3!ro I rr i 39-8 ! ^■2•!) i&2 4«-8 ! o0-4 r,n-3 48' I 44-0 4yl j 507 508 4S-2 44-2 4'J-() 4'2-3 Mid. \i A.M. 4 A.M. Mfian. o i o I o o 38'8 107 410 3!)-5 t 40-2 3!)-6 44 "2 41'6 f° ! Mean. , 3U-40 42t).-. ^ 46-35 i 48-y5 I 50-5.i i 50-55 4815 44-10 12-15 I 1085 ; 3()-8? 39-20 44-4 Temperature at the several observation hours higher (-4-) or lower ( — ) than the Mean Annual Temperature. Toronto...,! —5-0 - l-r5, + I'raguc. ■47 • a-fi I + 1-1)5 I + 4-45|+ti-l;-) +()-15 +3-;5J-0-3 -1-25 I — 3-55 - 4-55|- 5-2 0-y 1 + 3-8 +5-2 + 5-1 i+ 3-; +0-8 - 1-1 !- 2-3 |- 3-4 - 4-4 Toronto proportionally colder ( — ) or warmer ( + ) than Prague at the several observation hours. - 0-3 + 0-85 + 1-05 + 0-6.-) + 0-y5 + 1-05 + 0-051 - Tl , - 0-15 - 1*25 - Mo _ 0-8 I I If ve take the difference between the mean temperature at Toronto derived from all the observations ( t4°'4), and the mean of all the temperatures ob- served at each of the observation hours, we have the mean diurnal march of tlie thermometer as shown in the table, or how much the temperature amount is above or below its mean at each hour of observation. In the line iiuinediately beneath the diurnal march of the tempc : t ire at Toronto, is placed the diurnal march at Prague, by which means the ,'. neral resemblance and the minor differences can be at once perceived by the eye. These latter are furtiier shown in tlie last line, which points out the hours win n the temperature is proportionally warmer at Toronto than at Prague, which hours have a + sign before them, and those when it is pro- jiortioually colder, which are characterized by the — sign. It will be at once obvious that the climate at Toronto is proportionally warmer during the liours of the day, and colder during those of the night, than at Prague. Toronto being in a lower latitude and therefore nearer the sun, the sun's in- fluence is proportionally greater during the hours of the day; but in the absence of th(> sun, the ])owerful causes which, in spite of the difference of latitude, depress the isothermal lines, show their unchecked influence in the proportionally lower temperature of the hours of the night. So strong inde(>d are those; cau;;es, that at no one hour of the twenty-four does the absolute temperature at Toronto rise to an equality with that of Prague. * Tho l)uil(ling of the observatnn' at Toronto having heen completed in September 1810, the oltservations now uikUt notice commence with October 1840. The year 1841 in this communication is tlierefore more strictly the year which commences October 1, 1840, and ends ScptemtuM- 150, 1841. in like luamicr 1842 coimiiences whh October 1, 1841, and ends with September 30, 1842. 6 REPORT — 1844. The nights being proportionally colder and the days wanner than at Prague, the mean daily range of the thermometer is greater, being 9°*9 at Prague and 11°'35 at Toronto. The mean temperature of the 24 hours occurs earlier in the forenoon and earlier in the afternoon at Toronto than at Prague. Annual Variation. — The next table exhibits the mean monthly temperatures in each month of 1841 and 1842, and their average. In a separate column is shown the amount by which the temperature in each month exceeds or falls short of the mean temperature of the year. This forms the annual variation of the temperature ; it is, as is well known, the consequence of the earth's annual motion in its orbit, which regulated the order and succession of the seasons, and occasions a progression of temperature from a minimum in the midwinter to a maximum in the midsummer. This also is a single progression, having but one ascending and one descending branch. The annual variation of the temperature at Prague is placed by the side of that at Toronto, by which means the eye is at once enabled to judge of the general agreement and the minor differences ; the latter are also shoM'n more distinctly in the final column. Toronto. Prague. Mean of 20 years. The several months above (+) or below ( — ) the annual mean. Toronto proportionally hotter (+) or colder (— ) than Prague. 1841. 1842. Mean. Toronto. Prague. January o 25-6 23-2 281 39-5 512 661 65 -4 64-5 61-3 447 357 24-8 o 27'8 28'0 362 436 498 56-6 64-8 657 55-8 41-9 35-3 29-8 267 25-6 321 416 505 61-3 65 1 651 58-5 43-3 35-5 27-3 o 26-9 30-8 38-6 48-8 580 646 68-1 667 60-2 501 38-8 330 -177 -18-8 -123 - 2-8 + 61 + 169 +207 +207 + 141 - 11 - 8-9 -171 -21°8 -17-9 -101 + 01 + 93 + 159 + 194 + 180 + 115 + 1-4 - 9 9 -157 o +4-1 -0-9 -2 2 -27 -3-2 + 10 + 13 +27 +26 -2-5 + 10 -1-4 February March April May June July August September October November December Mean 442 44-6 44-4 487 1 1 Difference between the hottest and coldest month. Prague 41°-2 Toronto 39°-5 In viewing the minor differences shown in the last column, we must not overlook, that our numbers are based on t'vo years only of observation, and that for an annual progression, a single year forms in fact but a single ex- periment. When we view the differences which some of the months present in the columns representing the observations in 1841 and 1842, we shall readily acknowledge tliat more than two years are required to give that approxima- tion to a mean annual progression which the present state of science requires. There are, however, some features of difference which present such obvious characters of system that we may have reason to expect that the observations of a greater number of years will but make them more assured. Thus the spring months are all proportionally colder, and the summer months hotter, at Toronto than at Prague. There is also one remarkable difference, viz. in January, which is proportionally a colder month by above 4° at Prague than at Toronto ; and from the magnitude of the amount, it wears the aspect of a permanent climatological difference. Now it is well known that in the month of Januarj ing with it America, occupy to( climate ; elaborate to impress from long severing s January, and cold coldest an than at T< It is a temperatu in spring perature i whilst at I have i three yea maximum three yeai 1842 at range is c ceeded bj Jauuary Februar; March.. April .. May .. June .. July .. August Septem Octobei Noveml Deceml Toron * The the series ON THE METEOROLOOY OF TORONTO IN CANADA. of January the wind from the east and north-east prevails in Europe, bring- ing with it our severest winter cold. This feature has not a parallel in North America, where the cold of winter is more equably distributed. It would occupy too much time to discuss the cause of this peculiarity in the European climate ; and I must content myself with referring generally to M. Dove's elaborate work on the distribution of temperature ; a work which cannot fail to impress the reader strongly with the value of the conclusions to be derived from long-continued series of observations subjected to a laborious and per- severing study. It is a curious result from this excess of cold in Europe in January, that notwithstanding the greater proportional warmth in summer and cold in spring at Toronto, the extreme difference, or that between the coldest and the warmest month of the year, is absolutely greater at Prague than at Toronto, being 41°"2 at Prague and 39°"5 at Toronto. It is a consequence of the minor differences already pointed out, that a temperature equal to that of the mean temperature of the year occurs later in spring and earlier in autumn at Toronto than at Prague ; and that the tem- perature is higher than the mean of the year during seven months at Prague, whilst at Toronto it is only so during five months. I have inserted in the next table the mean range of the thermometer during three years at Toronto and at Prague. It must be understood that the maximum of each month inserted in this table is the mean maximum during three years; viz. March 1840 to March 1843 at Toronto; July 1839 to July 1842 at Prague; and the same is to be understood of the minimum: the range is consequently a mean range during three years, and is of course ex- ceeded by the range in individual years. Range of the Temperature in different Months. Toronto (3 years). |! Prague (3 years). Max. Min. Range. ' Max. Mill. Range. Jauuary February +47-3 +427 +591 +72 3 +757 +82-3 +85-5 +81-8 +78-2 +656 +57-6 +42-6 + 1°8 - 10 + 7-0 +230 +29-5 +372 +451 +47-0 +320 +25-5 + 127 + 37 45°5 437 52-0 49-3 462 451 40-4 34-8 462 401 44-9 1 390 : 1 +46°8 +439 +54-8 +726 +83-5 +880 +920 + 84-0 +82-5 + 69-8 +59-5 +470 + 40 + 16 + 13-8 +29-1 +40-0 +47-0 +50-6 +48-4 +40-2 +31-4 +295 + 124 o 42-8 423 410 43-5 43-5 410 414 356 423 38-4 300 34-6 April June July August September October November December Mean range ... 439 1 Mean range ... 397 Toronto / "'K'^««*' J^n^ 29, 1841 +917 p,.,^„e / "ig'^^^*' ^"^y \^' '^^^ +97-8 Toronto 1 Lowest, Feb. 16, 1842 - 8-2* ^ "'S"^ Lowest, Dec. 15, 1840 - 7-0 Range ... 99-9 Kange ... 104-8 * The thermometer ranged much lower in January 1840, before the commencement of the series under notice, viz. — January 2nd — 175 January 15th — 8-5 3vd - 92 „ 16th - 150 „ -Ith -100 „ 17th - 19-2 lowest observation. REPORT— 1844. Here also the general character shown by the comparison of the two sta- tions is that of very close resemblance, while the minor differences also stand out prominently. The greater variation to which the temperature is subject at Toronto in INIarch and April is very obvious in the column of range; as is also the small amount of the variation in the month of November at Prague. Tlie mean monthly range deduced from the twelve months is 43°*9 at Toronto, and S9"*7 at Prague; a considerable amount of difference, and which marks the greater general vicissitude of the climate of Toronto : still it is deserving of notice that Prague is occasionally liable to fully as great, and (during these three years at least) even greater extremes of temperature than Toronto, as is shown by the memorandum at the foot of the table ; it is indeed curious to remark how very nearly the stations apj)roach each other in the extreme amount of their thermometrical range. July and August are the only months in which during three years the observations at Toronto never show a tem- perature of the air so low as the freezing point. At Prague there are five months, viz. fiom May to September inclusive, in which during tin; three years the temperature was never observed so low as .S2^. If we seek in the old continent a station most nearly isothermal with To- ronto, we must refer to a latitude considerably higher than Prague. The station in M. Mahlmann's list (Dove, llepertoriuni, b. 4, and Humboldt, Asie Centrale, torn. 3.), which most nearly resembles it in the mean temperature of the different seasons, as well as in that of the whole year, is Wexio in Sweden, in latitude 56° .53', and height above the sea 450 Parisian feet. Toronto is in 43" 39', and height above the sea 330 English feet. The mean temperatures are — Spring. Suiuiner. Autuiun. Winter, o Toronto 41 "4 Wexio 41 '5 Summer. Autumn. Winter. Ainiual. Coldest month.Wt-irmest month. 63'H 45-8 26-.5 44-4 25'6 6.5-1 63-8 44-8 27/8 44-5 27-0 f36-0 Aqueous Vapour. I proceed to consider the elastic force or tension of the aqueous vapour contained in the atmosphere, and the degree of humidity produced by it, together with the diurnal and annual variations of these phienomcna. The elastic force of the vapour is considered to be one of the constituents of the pressure upon the surface of the mercury in the cistern of the barome- ter, which, conjointly with the other and much larger constituent, viz. the pressure of the gaseous atmosphere, produces what in conmion parlance is called ihQ pressure of the atmosphere^ measured by the height of the mercurial column in the barometer. Although we have no instrument by which we can measure the gaseous pressure independently of that of the acjueous vapour, we possess in Daniell's hygrometer, and in the wet and dry thermometers, the means of ascertaining the aqueous pressure at any instant independently of the gaseous pressure; and therefore, by the combination of the barometer and of the wet and dry thermometers (or of the hygrometer before mentioned), we should be able to obtain separately the pressure o| The very nei I)res8ur([ also be ductingl servatioT This is once bi all the we obtl servatiJ Onil reprt'sJ the coif Thus fatigable rical Ob- s already ly obser- liinum of the niini- naximum ice of the 1 warmed 'ise, occa- The sea I its turn nd though ing cur- iate rapid very early march of na of this ice of the when duly ice with it. mates and continental which they pter in the y humidity ion. reater ( + ) less (-) an the an- ual mean. •127 — ■13« •113 •073 — •01 fi + •140 ■f •184 i- •227 ■f •113 •027 — •080 — •161 y is shown, )f the year, The drier lie most hu- lary. When 1 the air re- ON THE METEOROLOGY OF TORONTO IN CANADA. 11 ceives the addition to its vapour required to maintain an equal degree of humi- dity, and the air becomes in consequence drier. This is even the case in the neighbourhood of extensive lakes, as at Toronto. May is the driest and De- cember the most humid month in the year: and this is also stated to be the case in Europe. When we turn to the table in which the mean monthly tension of the vapour is shown, we see most distinct!} marked the connexion between the temperature and the vapour pressure, and the dependence of the one upon the other ; we see a simple progression, the turning points being the same as those of the temperature, and a march as harmonious as we are perhaps en- titled to expect from observations of only two years' continuance. I shall reserve what further I may have to say in regard to the range of the vapour-pressure in different months, until we have before us the other constituent of the barometric pressure, viz. the gaseous atmosphere, to which I now proceed. Atmospheric Pressure. I Toronto. fi A.M. 8 A.M. 10 A.M. Noon. 2p.m.|4p.m. 6p.m. 8p.m. 10 p.m. Mid. 2 A.M. 4 A.M. Mean. ■Mcun bar. n841. I'rt'ssure. . 1 1842. •624 •6:t7 •638 •6l6 •595 •591 ■898 ■609 ■613 •607 ■606 •610 612 •613 •6-28 •631 •612 •594 ■590 •595 •602 ■603 •896 •593 •898 ■604 29 inch. + Lfllean Dpihict pressure of the vapour. . . '618 •632 •634 •614 •594 -590 •596 •605 ■608 •601 ■600 ■602 •608 ■242 •260 •270 •282 ■285 ■280 ■269 •257 •260 •243 ■238 •234 •259 Press, of the ga-" seous atniosph. ■376 •372 •364 •332 •309 ■310 ■327 •348 •358 ■388 •362 •308 •349 '29 inches + . . i Pressure ut eaeh"1 j liour(treater( + ) , or less ( — ) than + •027 + •023 + ■015 -•017 -•040 -039 -■022 -•001 + •009 + ■009 + •018 + •019 the mean annual [ pressure _ 1 1 Diurnal Variation. — The first two lines of this table exhibit the mean monthly pressure on the mercurial column at Toronto at the several observa- tion hours of 1840 and IS^l, — the mean of the two years is shown in the third line. The close accord of the mean pressure at the same hours in each of the two years is a very satisfactory testimony of the confidence to which these barometrical results are entitled : the mean at each hour of each year repre- sents about 311 observations ; consequently in the two years the mean at each observation hour represents about ()22 ohservations, the mean of all the hours in tlio one year 373'2 observations, and in the two years 7464 observations. The diurnal march of the barometer may consequently be regarded as a very near approximation to the truth. The diurnal march of the vapour jiresaure is obtained by an equal number of observations, and may therefore also be viewed as a very near approximation to the facts of nature. By de- du(!ting the vapour pressure from the whole barometric pressure at each ob- servation hour, we should obtain the daily march of the gaseous atmosphere. This is shown in the fifth line of figures in the table ; and by taking the differ- oiieo between the last column, (?. e. between the mean gaseous pressure at all the observation hours in the two years,) and the pressure at each hour, we obtain the amount by which the jiressure is greater or less at each ob- servation hour than the mean general pressure at all the hours. On first casting our eyes (in the last line of the preceding table) on this rcjiri'seiitation of the diurnal variation of the gaseous atmosphere, freed from the complication which its combination with the vapour pressure produce* 12 REPORT — 1844. in the indications of the barometer, we cannot fail to be immediately struck with the very close correspondence of the diurnal march before our eyes with that of the temperature which we have already examined. The maximum of pressure is at 6 a.m.; the minimum at 2 p.m. The progressions take place in the opposite or inverse sense to each other, but they are remarkably har- monious, and leave no doubt of a mutual connexion, and of the dependence either of the one on the other, or of both on a common cause. An explanation of this connexion, which presents itself to the mind as soon as the facts are clearly perceived, may be thus stated : — As the temperature of the day increases, the earth becomes warmed and imparts heat to the air in contact with it, and causes it to ascend. The colunm of air over the place of observation thus warmed rises, and a portion of it difluses itself, in the higher regions of the atmosphere, over adjacent spaces where the temperature at the surface of the earth is less. Hence the statical pressure of the column is diminished. On the other hand, as the temperature falls, the column con- tracts, and receives in its turn a portion of air which passes over in the higher regions from spaces where a higher temperature prevails ; and thus the sta- tical pressure is augmented. This explanation is merely the extension to the particular case of the diurnal variation, of principles which have long been familiar to meteorolo- gists in accounting for various other atmospherical phaenomena, such for example as monsoons, and land and sea breezes. To make the parallel com- plete, it should be shown that, when the temperature rises, an influx of air takes place towards the lower part of the column, proportioned to the ascend- ing current, and tending to replace the air wliicli is thus removed. The obser- vations which will be cited in the sequel of this communication will show that such is precisely the fact at Toronto. The force of the wind, taken without reference to its direction, has also its diurnal variation, corresponding in all respects with the diurnal march of the temperature and of the gaseous pressure ; being a minimum at 6 a.m., and a maximum at 2 p.m. — increasing with the augmentation of the temperature, and decreasing with its diminu- tion. The air which thus flows in, becoming warmed, pursues in its turn the course of the ascending current. We have thus the double evidence of the ex- istence of this current, — 1st, in the diminution of pressure, showing the out- pouring at one extremity; and 2nd, in the increased force of the wind, showing the inpouring at the other extremity. As the temperature keeps continually rising, both the demand for and the supply of fresh inflowing air progressively increase. The diminution which the gaseous pressure continues to undergo as long as the temperature continues to rise, shows, as we might naturally ex- pect, that the supply is continually somewhat in arrear of the demand. The diminution of the gaseous pressure and increase in the force of the wind being consequent on the rise of the temperature, the turning points of the two former phaenomena might be expected to occur somewhat later than the instant of minimum temperature ; and this appears by the tables to be the case, but will probably be more clearly shown when the hourly observations shall come under review. Annual Variation, — Let us now proceed to the mean pressure of the gaseous atmosphere in each month of the year, and its consequent annual va- riation. These are shown in the following table : — January . February. March.... April .... May .... June .... July August . September October November December Mean .. In turn of the me perceive a find the pi and augm march of ' evidence v determine, are mere a disappear, (possibly ( yet unrecc I will ni which prc! year. It is atniosphor pressure, 1 of teniperi increase o I'H'Hcts of ( rcuiiiins v( no trace m The pri tlic annul * The vci sevcrnl year of othfM' flu proceed froi recogiiisablt portion of ronto may of very mar each year ii ON THE METEOROLOGY OF TORONTO IX CANADA. 13 Mean Monthly Pressure. con- 1 of the nual va- Toronto. Prague. Barometer. Vp.pour. 1 1 1 Gaseous pressure. Gaseous pressure in each month creater ( + ) or, less {-) tham the mean an- nual pressure. Gaseous pressure. Gaseous pressure in each month neater ( + ) or less (-) than the mean pressure. 1841. 1812. Mean. January February March April May June 29 664 29 508 •489 ' -548 •657 i -638 -621 ! -548 •645 ! -58!) •543 -585 •620 i -655 29-586 -518 •647 •584 -565 -564 •637; •70J; •634 ! •639 i •592 •625 i 1 132 •122 •146 •186 i -243 -399 -443 •486 •402 •232 •179 -137 29454 •396 •501 •398 •322 •165 •194 •219 •232 •407 •413 •488 +•105 + 047 + 152 + 049 -027 -184 -1.55 1 -130 ; -117 +•058 + 064 i + 139 1 29-213 29-227 29089 28973 28-923 28-898 28'861 28882 28912 29-045 29 047 29163 + 194 +•208 +•070 -046 -096 -121 -158 -137 -107 + 026 +•028 +•144 July August September ... October November ... December ... •698 •6)6 •636 •615 •652 •712 -662 -6i3 -568 •597 Mean '29612 29-604 1 1 29 608 j -259 29 349 1 ! 29-019 In turning our attention to the column which exhibits the excess or defect of the mean monthly pressure on the mean of all the months, we at once perceive another illustration of the principle which has been just stated. We find the pressure of the ga.<;e()us atmosphere diminished in the summer months and augmented in the winter months. The general dependence on the march of the temperature is manifest; and it must remain for the additional evidence which will be produced by the observations of subsequent years, to determine, whether the minor deviations from a perfectly harmonious march are mere accidental differences, which a wider observation basis will cau.se to disappear, or whether they may not point to some other periodical influence (possibly of the temperature also, but of a less direct nature) which is as yet unrecognized*. I will now ask the Section to turn its attention for a moment to the column which presents the mean height of the barometer in each month of the year. It is curious to observe how completely the annual march of the gaseous atmosphere is masked in the barometer by its combination with the vapour pressure, both being measured iu one by tlie mercurial column; the increase of temperature, which causes the giiscous pressure to diminish, occasions the increase of the vapour, and rire versa ; and so nearly are these two opposite effects of the one cau«e balanced at Toronto, that the height of the barometer renmins very nearly the same in every month of the year; or at least, shows no trace whatsoever of an annual period. The principle which has been tluis adduced for the purpose of explaining the annual and diurnal inaieh of the atiiiosph(!ric pressure should be ge- * Tlie very few mcteorolngicul registers, which have been maintninrd with proper rare for several ycurt together in Europe, are stated to aff'oid very di-cided iiidicutions of the existence of othrr fluct\iations besides the annual and diurnal variations, which apparently do not proceed from merely local causes, hut recur regularly at stated periods of the year, and are recognisable simultaneously over widely extended spaces, such for example as a considerable portion of an entire continent. How for the higli pressure of the month of March at To- ronto may be a phflenomcnon of this class it may perhaps take some years to decide. It is of V017 marked character, and is shown decidedly in both years. As 1 have already remarked, each year is but a single experiment in investigations of annual phscnomeua. / 14 REPORT — 1844. neral in its application. I have inserted in the table the gaseous pressure at Prague, as it is given by M. Kreil in his ' Jahrbuch' for 1843, from the observations of three years. The laarch of the vapour, as far as it has yet been determined at Prague, does not present a curve agreeing quite so satis- factorily with that of the temperature as we have been able to deduce at Toronto: whether this arises from disturbing influences in nature (such possibly as indirect influences of temperature), or whether it will disappear by longer-continued observation, cannot be yet anticipated. What is still uncertain, however, at Prague, is not of magnitude sufficient to obscure the dependence of the annual progression of the gaseoas pressure on that of the temperature. The measure of agreement in this respect at the two stations cannot be viewed otherwise than as highly interesting and satisfactory. Mean quantities derived from a greater number of years will in all proba- bility show even a closer accordance. We will now revert to the maximum, minimum and range of the vapour pressure in the several months of the year, for the purpose of showing that its variations are such, as to seem to claim a greater attention than they have hitherto received, at the hands of those who are engaged in investigating the non-periodic fluctuations of the atmosphere, by the comparison of observed barometrical heights. In the next table we have the maximum, minimum, and range of the vapour pressure at Toronto, taken from the mean of two years. By thus exhibiting the mean quantities only of the two years of observation, extremes are of course somewhat moderated ; but, on tlie other hand, there is the advantage that the numbers are probably a more faithful representation of what may be expected in ordinary course. Range of the Barometer. January .. February.., March April May June July August ... September October .. November December Mean .. Toronto. in. 1-335 1-221 1-275 1190 0-846 0-623 0-696 0656 0-754 0-934 0-945 1-527 1000 Prague. in. 1-364 1-156 1-158 0-864 0-881 0-873 0-593 0-647 0-755 0-828 1-036 1-222 0-950 Maximum, Minimum, and Range of the Tension of Vapour. Toronto — Mean of 2 years. Max. in. •221 •262 -350 •385 ■532 •709 •775 ■762 •727 •487 •375 •263 •486 Min. in. •050 -050 -045 •085 •105 •143 •202 •262 •158 •096 •0<)6 •048 Range. •171 •212 •285 •300 •427 -566 ■573 -498 -569 -391 -309 -215 •109 -377 Prague — Mean of 2 years. Max. in. -306 -238 -278 •406 -555 -659 ■662 -556 •567 •447 •414 •300 ■449 Min. in. •051 •052 •067 •149 -163 -222 -245 -257 -217 •124 •138 •058 Range. in. •255 •186 •211 •257 •392 •437 •417 •299 •350 •323 •276 •242 •145 i ^304 We here perceive that the mean monthly range of the tension of the vapour falls little short of four-tenths of an inch ; and that in the summer months of June, July, August, and September, wIkmi it i« greatest, it is very little less than the whole range of the banmieter in the same months. Win- ter is the .season for the great tiuctuations of the barometer ; sununor for those of the vapour pressure. If, as i.s believed by many modern meteorologists, the fluctuations of the vapour pressure aflTect the barometer to their whole extent, tlien the fluctuations of the gaseous atmosphere at Toronto approach much tieari those of thi by a rise ii the tension meter and In a chang of the gase which is pi force of th pressure ai instances ii Betw( >> » » If the prin consequei of their vs of which such com] the tensio When ca observati( never ma were caps The CO and Prag are the p continent The CO exhibits ( range of which til vicinity. It nia]^ vations i vpl of ea The h within a a year ei Max Mill Weh if we th the pres ON THE METEOROLOGY OF TORONTO IN CANADA. 15 d. h. Between May 30 16 „ June 11 „ June 30 2 „ July 2 () „ July 23 4 Auff. 18 2 d. h. June 5 4 under 6 June 15 10 ., 5 July 2 6 July 5 4 July 25 Hi Aug. 23 14 „ 3 „ 3 „ 3 » 6 much nearer to an equality in the two seasonsof summer and winter, than do those of the barometer. A north-west wind at Toronto is usually accompanied by a rise in the barometer and a fall in the temperature with a diminution in the tension of vapour ; and a south or south-east wind, by a fall in the baro- meter and a rise in the thermometer with an increased tension of vapour. In a change from one of these winds to the other, consequently, the alteration of the gaseous pressure would be greater than that of the barometric pressure, which is partially counteracted by the accompanying change in the elastic force of the vapour:, and as already noticed, the fluctuations in the vapour pressure are very considerable in summer. I have selected some remarkable instances in a single year, 1841, which are as follows: — Variations of Vapour Pressure in 1841. and June 5 4 under 6 days 0*594 0-503 0-610 0-465 0-500 0-496 If the principles are correct, of which we have here traced a portion of the consequences, barometrical observations generally must lose an essential part of their value when unaccompanied by hygrometrical observations, by means of which the pressures of the air and vapour may be separated. Whenever such complete observations are made, t. e. hygronietric as well as barometric, the tension of vapour should be computed on the spot and at the instant. When calculations of this nature are suffered to fall in arrear, unreduced observations accumulate, and danger is incurred that the calculations are never made, and that science will lose the advantage which the observations were capable of affording. The comparison of the barometric range in the different months at Toronto and Prague exhibits a very satisfactory accordance, and shows how similar are the phaenomena which present themselves in this respect over the two continents. The comparison of the range of the vapour pressure at Prague and Toronto exhibits only such diff'erenccs as may be reasonably ascribable to the greater range of the temperature at Toronto, and possibly to the greater facility with which the air can acquire viqiour at that station fioin the great lakes in its vicinity. It may l)e worthy of notice, tiiat llie highest and lowe-t barometric obser- vations in the two years at Toronto occurred within a very few days' inter- val of each other, being apparently parts of one great atmospheric wave. The highest and lowest baronicjlric observations at Prague also took place within a few days of each other, and at the same season, viz. midwinter, but a year earlier. The observations were as follows, viz. — Extreme Range of liaionieter iti 1840, 1841. Toronto. Piaguc. Dec. 22, 1811 . . . . 30-417 Doc. 27, 1840 . . Dec. 4, 1811 .... 28-672 Jan. 4, 1841 . . Max. Min. 30-260 28-654 Interval 18 days 1-715 Interval 9 days 1-606 We have undoubtedly made n considerable step in advance in meteorology, if we thus correctly substitute the consideration of the separate daily march of the pressures of the vapour and of the gaseous atmosphere, for the compara- 16 REPORT — 1844. \* tively profitless study of the complex efiect produced on the barometer by the operation of these two distinct agencies. The labour has been by no means small which has been bestowed in the endeavour to generalise the diurnal phaenomena of the barometer by the formation of empirical formulae ; it has been in many instances the labour of highly accomplished men: but we have the recent acknowledgment of a valued and distinguished member of our own body*, who has himself engaged in this inquiry, that it failed in conducting to a recognition of the causes of the phaenomena. On the other hand, the moment we apply ourselves to the contemplation of the separate phaenomena of the vapour and of the air, there appears to be revealed to us a simple and beautiful dependence of each upon the diurnal march of the temperature, producing effects which in their combination seem also to afford a full and perfect solution of the problem of the daily rise and fall of the barometric column. It would be unjust to the meteorologists of Germany if we were not grate- fully to acknowledge in how great a degree this advance in the science is to be ascribed to their writings, and especially to those of M. Dove. Their mete- orological researches have been pressed with an assiduity and devotion of labour which is beyond all praise. In the consideration which we (the mem- bers of the British Association) are likely soon to be called upon to exer- cise, whether any and what great combined endeavours are further desi- rable to be made for the advancement of meteorological science, we should be indeed inexcusable if we neglected to avail ourselves of the advice, and look with becoming respect to the opinions, of men, who have spent years of untiring labour, and brought great attainments to bear, on a branch of science which has been comparatively less cultivated by ourselves. Admitting M. Dove's views, we can easily perceive that an empirical for- mula, in which the diurnal oscillation of the barometer should be made to vary as a function of the latitude, could never universally represent the phaenomena. The difference between an insular or littoral station, where the vapour pressure attains its maximum at 9 in the forenoon, and an in- terior station in the same latitude where the maximum is at 2 or 3 in the afternoon, cannot both be represented with fidelity by a formula in which this difference is not taken into the account. At stations where the maxi- mum of vapour pressure takes place at 9 a.m., and the tension thencefor- ward descends until the afternoon, — (as at Trevandrum), — the range of the diurnal oscillation of the barometer will be greater, ceteris paribus, than when, as at Toronto, the vapour pressure progressively rises from sunrise to a maximum at 2 or 3 in the afternoon : the hours of maximum and mi- nimum will also be somewhat modified. The important problem of the equality or inequality of the mean press- ure of the gaseous atmosphere at the level of the sea at different points on the surface of the globe, has lately begun to occupy the attention of phy- sical philosophers in a degree which will probably tend, before many years, to its practical solution. In this labour the determinations of our co-operative observatories may perform an important part. Great care has been taken that the barometers of our colonial observatories shall speak precisely the same language as the standard barometer in the Royal Society's Apartments ; and steps are now taking to ensure a similar comparison of the barometers, which, in difterent parts of the United States, are now observed simultaneously with Toronto by our American coadjutors ; and which may hereafter, if that obser- vatory should be continued, form a very valuable extensive basis of induction for the movements of the atmosphere over that great continent. • Profetiur J. D. Forbti; Meteorological Report. ON THE METEOROLOGY OF TORONTO IN CANADA. 1? Prague and Toronto furnish the materials for an interesting comparison of their respective mean gaseous pressures. I have exhibited this com par son in the subjoined table. After the proper corrections have been applied for the reduction to an invariable scale of pressure, and of the pressure itself to a common elevation above the sea, the residual difference in the pressure is about four hundredths of an inch. This is within the amount of diifererce that might reasonably be expected in so indirect a comparison. The infer- ence therefore at present must be, that no unaccounted for difference of pressure exists, or at least next to none, at these two stations in Europe and America. Inches. Pressure of the dry atmosphere at Toronto .... 29*349 Pressure of the dry atmosphere at Prague .... 29*019 Difference 0-330 Reduction to an invariable scale of pressure. , . . 0*017 True difference of pressure 0*313 Difference of elevation equivalent to 0*273 Difference of pressure unaccounted for 0*04 M )dern researches have shown that the height of the barometer at dif- ferent points of the earth's surface is not only disturbed by self-adjusting causes which produce temporary displacements, but that there are causes in action which effect persistent differences in the mean height of the barometer in different localities, strictly at the level of the sea ; so that, to use the words of Bessel, the mean atmospheric pressure depends on the geographical co-ordinates of a station in latitude and longitude as well as in elevation. This remark of Bessel's is founded chiefly on Erman's observations* ; and Erman himself, who has considered the effect of the vapour pressure upon his barometrical heights, concludes that the pressures which the air would have exerted without the pre.sence of aqueous vapour, indicate also persistent dif- ferences of mean gaseous pressure depending on geographical position. The instance quoted by Professor Forbes from Captain Kingf, who found the mean height of the barometer 29*402 in observations repeated five times a day in five consecutive months of summer at Port Famine, is an example of an atmospheric valley, as it has been called, in the former sense, but not in the latter. When allowance is made for the probable vapour pressure, the gaseous pressure at Port Famine will be found greater than its ordinary amount at the Equator ; where indeed other observations have indicated a gaseous pressure lower than in the adjacent extra-tropical latitudes. Assumed eijuatorial barometer 29*95 Deduct vapour pressure (assumed dew point 74°) 0*83 Mean pressure of the gaseous atmosphere at the Equator 29*12 Barometer sit Port Famine in five summer n>onths 29*4G2 Deduct vapour pressure (assumed dew point 38°) '230 Pressure of the gaseous atmosphere at Port Famine .... 29*23 + * Erman, Met. Beob. bei ciner Seercise um die Erdc t Forbes, Reports of the Brit. Assoc, 1832. i This is of course only an approximate comparison ; to render it more exact, it would be 18 REPORT 1844. In these last remarks I have perhaps ventured further from the strict sub- ject of this communication than I should have been dis})osed to have done, had I not had in view to call the attention of the Section to what it is in the power of our own country to accomplish, with its widely extended dominions, in the solution of this great problem of the uniformity or otherwise of the mean pressure of the atmosphere, by the establishment of colonial observato- r'"s, conducted on a systematic plan, and continuing in operation only until certain specified and definite objects should be attained ; such, for example, as the mean values, and the periodical variations, of the several meteorological elements. The present communication is an evidence of the important re- sults which even a very brief duration of such observations may be sufficient to accomplish. When such establishments are proposed, with tlie sanction and support of the colonial autiiorities, and with the advantage of men of assured competency to conduct them, we may venture to promise the fullest co-operative aid (that may be compatible with circumstances) on the part of the British Association, which has placed foremost amongst its ol)jects "to give a stronger impulse, and a more si/sfema(ic direction to scientific inquiry." I have one more point to bring under your notice; a point highly inter- esting in itself, and completing the evidence of the harmony in the meteo- rological variations. It has been noticed that from the diminution of tlie gaseous pressure as the temperature of the day increases, evidencing an ascending current, we should be prepared to expect a corresponiling influx of air at the station, or a diurnal variation in the force of the wind (taken without reference to the direction from which it blows), wliicli should have its minimum at or near the coldest hour of the day, and its maximum at or near the warmest, and its pro- gression in harmony with the curve of temperature, having one ascending and one descending branch. Such is the fact. Tlie subjoined table exhibits the sum of the pressures, expressed in pounds avoirdupois, exerted on a square foot of surface at Toronto, at each of the observation hours in 1841, and the same in 1842. The wind is proverbially uncertain, and our means of measuring its pressure are more imperfect than we could desire ; but these numbers afford an ample evidence that there is a diurnal variation in the force of the wind, and furnish a curve which, when projected, is found in remarkable corre- spondence with the curve of the temperature. Tiiis fact, observed at Bir- mingham by Mr. Osier, has been already brought under the notice of the Association at a former meeting. The diurnal march of tin; gaseous atmo- sphere furnishes the additional link in the chain of evidence, by winch the connexion between the temiierature (producing an aseentiing current) and the force of the wind (flowing in to replace it) may receive its explanation ; placing before us in an intelligible form their mutual relations to each other, as cause and effect. 1841. 1842. I neccssai7 to regard the influence of the season of the year (summer) at wliieh the barometer was ohserveil at I'ort Famine ; as well as the correction due to the etVctt of the variation of gravity on the standard of measure. Iloth corrections would tcml to increase the mean pressure of the gasenus atniosiihcre at I'ort Famine in comjiarison with that at the E(|uator. The barometrical ohscrvalions made in the Ereb\is, in liie late Antarctic Exjiedition, fmiiish a beautiful illustration of the projtressive decrease in the height of the barometer from the tro])ics to the high latitudes, coincident with the diminiitidii of the eia^tic force of the va])our accompanying the decrease of temperature. I hope that Sir Janu's Koss will sliorti) publish these interesting observations, with the correspoudnig pressures of the gaseous atmospliere in the ditferent parallels. QN THE METEOROLOGY OP TORONTO IN CANADA. 19 itrict sub- ave done, t is in the ominions, ise of the ib.servato- |orily until example, |orologicaI Jrtant re- sufficient sanction If men of the fullest uc part of »j(^cts " to inquiry." hly inter- e nieteo- 'essure as rrent, we tation, or ce to the ■ near the^ d its pro- idingand ^libits the uare foot the same curing its ^rs afford he wind, e corre- I at liir- '■ of the IS atmo- liicii the and tlie mation ; li other, nrniiieter ■iatioii of lie iiioaii iMpiator. , funii^li Voiii tlie ft vapour publish phere in Sum of the pressures exerted by the force of the wind at Toronto on a sur- face of one foot square at the several observation hours in 1841, 1842. 6 a.m. 8a.m. 1 A.M. Noon. 2 p.m. 4p.M. P.M. 8p.M. 10 P.M. Mid. 2 A.M. 4a.m. lbs. 101 143 1841... 1842... lbs. 96 126 lbs. 164 156 lbs. 168 201 lbs. 186 238 lbs. 204 285 lbs. 1 lbs. 169 : 120 256 181 lbs. 109 123 lbs. 121 113 lbs. Ill 112 lbs. 103 128 Mean 111 160 184 212 244 212 1501116 117 112 116 122 Without ascribing anything like precision to the numbers in this table (which are however likely to be more correct in relative than in absolute value), they lead to the inference that the pressure of the wind, on the average of the whole year, is doubled, or nearly so, between the coldest and warmest hours of the day ; i. e. between 6 a.m. and 2 p.m. The confirmation, or otherwise, of this remarkable result by the observations of succeeding years cannot fail to be a point of much interest. It appears from the registry of Mr. Osier's anemometer, during four years at Birmingham, that at that sta- tion the increase in the pressure of the wind is considerably more than double between the hours of the minimum and maximum temperature. It will in- fluence many reasonings if it shall be found as a fact of pretty general oc- currence, that so large a portion of the daily wind is put in circulation to supply an ascending current*. Synopsis of the Diurnal Variations at Toronto. Obseri-ation hour. Temperature. Vapour pressure. Gaseoiu pressure. Force of wind. 2 A.M 39-8 39-2 Min. 39-4 42-6 46 3 48-9 50-5 1 X .'■•0-5/s 48-1 441 421 40-8 in. •238 -234 Min. •242 •260 •270 •281 •285 Max. ■279 •268 -257 •249 •243 in. 29-362 29368 29376 Max. 29-372 29-364 29 333 29-309 Min, 29 311 29-328 29-348 29-359 29-358 11)8. 116 122 111 Min. 160 184 212 244 Max. 212 150 116 117 112 4 A.M 6 A.M 8 A.M 10 A.M Noon 2 P.M 4 P.M 6 P.M 8 P.M lOp.M Midnight .... * To the agency of this current wc should probably ascribe the upward conveyance of the vapoMax. •626 •475 •606 •448 •468 •404 •364 •294 Min. •561 •331 •712 in, -140 -076 -054 -•078 +•008 + 107 + 179 +•095 -•038 -•058 -031 in. +•209 + 120 -031 + 160 -058 -038 -•102 -142 -•212 + 055 -175 +•206 Mean of the Year. 496 •326 29506 rvation hour »e estimation icular to the he square of oximately to e scales does )ressure8 are nd show the progression, ssure of the vation hours ressure, and The sign pressure. .( Toronto. in. + 013 + •019 + •027 + 023 + 015 -017 -040 -039 -022 -•001 +•009 + 009 - useous pre 8S- variation of ressure, a nd pressure o r Teater or les i mean annua 1 essure. in. •209 -120 •031 •160 •058 •038 •102 •142 •212 •055 175 206 1 ON THE METEOROLOGY OF TOKONTO IN CANADA. 2S It appears therefore that the annuul und diurnal variations derived from the observations at Greenwich present a mof^* satisfactory accordance with those at Toronto in those points which were brought ninst prominently be- fore the Association at York, and to which fhe attention of the Section was especially called, viz, — First, in regard to the diurnal variaii f : 1. The vapour tension and the force of fhe wind have each a minimum, and the gaseous pressure a maximum, at or near the coldest hour of the day. 2. The vapour tension and the force of the wind have each a maxinium, and the gaseous pressure a minimum, at or near the warmest hour of the day. 3. The diurnal march of each from the minimum to the maximum, and from the maximum to the minimum again, is continuous, like that of the tem- perature, without any interruption deserving of the name. -J-. At Greenwich as well as at Toronto the diurnal variations of the vapour tension and of the gaseous pressure, produce by their combination the double maxima and minima of the diurnal oscillation of the mercury in the baro- meter. Secondly, in respect to the annual variation : The annual march is somewhat less regular at Greenwich than at Toronto, being derived from the observations of a single year only ; but we have the same general features: a minimum of temperature and vapour- pressure, and a maximum of gaseous pressure in the midwinter ; and a maximum of tempe- rature and vapour pressure, and a minimum of gaseous pressure in the mid- summer. All the summer months are characterised by the + sign in the vapour, and by the — in the gaseous pressure ; and all the winter months by the — sign in the vapour, and the + sign in the gaseous pressure. I am unable at the present moment to pursue the comparison of the Green- wich and Toronto results in many other points in which I can perceive that the interest would prove an ample repayment for the time so employed. But I may hope to enjoy some future occasion of resuming the subject under more favourable circumstances in respect to leisure than I can at present command. PRINTED BY RICHARD AND JOHN E. TAYLOR, BED LION COOT, FLEBT STREET. 1 1: r^ he 7 fie /' / . he Ten he Fat W Mtdfi^ - .4 y - Meait Aqitevu-i Vufwiji' - Mfiin TeniperaUivt — —- — Jfeim Force it' Wind •^ ■% — Mrtui daxtcii^ I't-n'sure 5= ? w Mu(4i* (11., Ill/, I, ,A' I " 11/ , ,' ,1, iJiurn (I I Va rid 1 icn rf ' 7'he I'emptvatuve Tlif Fcrce of the Wirui Midnt •iAM -f 8 iV Mum Aqimti.s' \iifn ur Mt fui 7'niipf /•tt/uj't Minn Cn .1 i ii.s /'/'(SSUrt — ....^ MuOl' v. 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