Show the air W we e bra breathe te I 1 I 1 I 1 I 1 a 1 11 BT r J jamea r T W XA I 1 1 I I 1 the earth we is by adint alt atmosphere mo sphere or of air flie lie libit of known to be pt pi leest forty five mile it presses upon tile earth with a weight equal at vie the level of the soa sea to about fifteen pound pou on every squire inch 0 of j surf ce As we ascend high moun laina thi weight becomes less and auda as we go down into deep mildew it glie becomes comes greater i we breathe tins this air and I 1 w ve could not live a a silwe moment it floats q around the earth lit in alm si perpetual motion and 6 cording to the swiftness chit n noves mores oves it produces gentle bree breezes swift winds or tenable elble tornadoes I 1 I 1 though very familiar to us and alid ro I 1 girded with erttle it tle curi sity the ar air is yet very wonderful both in and lit in its uses I 1 I 1 though apparently pure and elementary it jucis is by no mearis means either a simple or pure substance it is a mixture inix of several seve rul different kinds of 0 matter each or of which perform a beauli beautiful ful and wise part jn in relation rela ioa tiou to animal and aad veritable vegetable life four substances at least are to be necessary to its composition two of these oxygen aud nd nitrogen form its entire bulk the two others ra t caa r la bouic acid and i watery matory vapor being onla 0 illy in minute quantities 1 1 OXYGEN ia a kind of air or gas which like the atmosphere itself is without color or smell A caudle burus burns in at with willi inucci greaf tir brillh Anci pud rapidity tty tt niu air 1 animals also breathe in ili it t with an increase so of plea pleasure sare but it their circulation them intha state of fever and finally kills them by excess excels of excitement faey live too tog rapidly it in pure oxygen gas aud burn barn away awa IQ in 1 it like fleri aig candle this gas I 1 can not be sedi in bv byrbe the eye or delisl belated ted byyny ot the other OARS its presence ofay baybo be readily perceived however Jio wever by the brilliancy with which a lighted caudle will burn when immersed iu in it I 1 I 1 if also 40 a ki kind PA of air which chic h like oxygen is void of color taste aud and swell emell tut but 0 abir trials beada tol to breathe introduce id dyllo jt 4 t oxygen is oue one amal art nitrogen nil ni rogen is one thirty sixth part lighter thau than common air CARBONIC ACID is a kind of air which tike like oxygen zlem aud atod nitrogen is void of color but unlike them possesses odor and a perceptibly sour taste burning bodie pape and animals avimalk amse to b reathe breathe when introduced into 1 it it is one halt half heaver than common air and cap therefore be poured through the air froia one vessel to another elfke water it Js is the of ef this gas which gives their sparkling briskness lp 40 fermented liquors to soda water and to tite the waters lof some wine ral springs I 1 1 I 1 I I 1 v WATERY is tile the ate steam arn ori orvator or vapor visible gr or invisible which ascends from frama 9 surface of water when exposed to the air lichen water 4 4 p upon the ground in ia dry weather it soon aisa disappears p ris rising ingli in invisible vapors and floating buoyantly among the other constituents cono titu edw of the phere i these jour f our substances a the lair air everywhere aad always contains con taina tain 4 they aro all necessary to tle the daily wants of animal nod and vagle vegetable taMe life biml the two gaces oxygen and nitrogen ni troge forn form so ito large a proportion of the whole wh ahat besase we t to 0 say of dry air that it consists lof arid and oxygen only in the proportion of four gallons of lite former to one of the OW latter morla cormay corm dy however air when deprived or of vapor and it contains con consists Apts fit one ban dred gallons of seventy nine of nitrogen mixed yath with twenty ono one of ot oxygen the carbonic acid exists iiii in proportion al ai ordinary ordia ary elevations awra 4 r 80 only 41 y about two gallons gallope of this gas in erys five thousand beair bof air it iacre increases ses bo however wever a we A ascend sa that at the heights of eight or ten thousand feet tue it of carbonic d r ill i even RPM W X il t y ia q quai u W tit ij 4 wm a yet its ts p h 1 I S ess essential gilt t 1 vegetables life pa flip laari being heavier than air i appears appear 9 gilr that the of this his gas gag should i cree crease as 48 11 wa baw the itile r I 1 natural tendency would aam seem tote tolie talner wi 0 toward the baftir eartha ana ii here to fona deadly atran neither mor pla f live but jmj anda as 4 bd aerial cm i rents which tend to mix and ble blend fid together L different gases of which tile the air consists all gaso ga i by a law of nature tend to diffuse theine elv vt each other ot herand and 11 0 o intermix more ol 01 speedily eveia even where me he utmost stillness pm oili f and no wind agitates them hence a aps lingi like hydrogen does notrice no not trise rise wholly to tile the regions of ti fedr there to float on n tho iho liei rier gases nor doss does a heavy gas like carbonic acid va eil sink k down so as 6 td rest aly beneath I 1 lighter gases I 1 a in obedience to tin this s law car carbonic boule acid 14 u 0 places slowly ria 46 a 4 os lowly sinks and I 1 nearly uniform purity is maintained iu in te air V breathe its presence cresence I 1 in ll 11 the a atmosphere alte 4 be shown ayze formation ti conof of a whit film odai of bonatz bonate of bf litile on the surface of limewater Hinc wat whit it is exposed to the air the watery vapor varies in quantity with 44 climate and temperature of the place jt I is iiii in cold reasons and climates gehe generally rally than h such as are hot it set lorn loni forma more nhsn a OIK I 1 sixtieth or less lead than one two hundredth of UK 16 bulk of the air its presence may be disco discovery in ili the hottest days by pouring iee ica celd water into ink a tumbler when the vapor odthe of the vir air will rapidly condense on the outer surface of tho vessel III i tile the form of dewdrops dew drops r r i from every breath of air which tap aap R draws into its lungs it extracts a quantity odai agen the oxygen thus thua obtained is a martof part of ole tina I 1 natural food atthe of the animal which it can abt obtain fro ii 11 no other natural matoral source id new supplied of 0 which are necessary to it eaf every 71 tin oxygen dx agen of the atmosphere theotore tore is w to the very existence of life in the orden of ani nals r tile the candle hurns burns also al and id all I 1 i laj W ies kin kildun dUn in the air only because it conta contains lits gen gell this gis is a kind ot of necebia nece iia flaming and fas burning bodies bodied so that were icat from tha earth p atral apher neither I 1 j AM ky I 1 W heated heat uld be rn combustible substances the proportion alsoc iii ia oxygen exist the air is adjusted to 4 the ie e xi sting things did the atmosphere consist of van 0 x only alie liveson live animals an i trials would I 1 bo 0 0 of f i mas hinesl I 1 ii dg duration ration and bodies bodies oven once sot ct oil on fire are would AvAM li 01 so arf fast 4 as to beconi be iceo yoni ifo co cocrel iio 81 ox oxygen agen is therefore mikeil aiu vi I 1 A la large r ge ipri W or of marogi n chiq thi g a s b a rm I 1 ese I 1 it ens it and I 1 prolongs its action I 1 on tj tie boyst bys t wa water ter diluted dalaw 1 wine or spirits its aw ay ass i too fier fiery Y influence anoa hafl animal frame e 10 every empry green leaf that wp waves yes 0 on n field if or 11 I 1 suck carb ilc a aau the ae air it t is is as to mhd 36 0 jab I 1 epla plant as oxygen is is to the alio I 1 life of lip anjain 01 it alj I 1 e move carbonic acid from awn tb the I 1 ai a and ana all asli 1 I 1 growth would wound cep J t us t t therefore ve be jy I 1 I 1 cesary constituent of I 1 the A atmosphere loop I 1 cerp R earth but carbonic a acid is poisonous olious 1 doai 0 AD it is jor or this aliis reason that hat the piro r portion orti onor al con contained bailie 1 d in ili the tur air ia ix so ao vr very I 1 small in 1 diw I 1 proportion much gr A I 1 MA lan it is is 1110 annne thay are now constituted could idl arm r ditl I 1 out injury iy ay ry to 9 fri belr lie walt gt oil the other oilier hand that jat ga A k lib aible le to obtain i 1 di rapi rapier of carbonic acid brorn a gaseous so little tiey ar aro digap to batig hangout han goit gt leany waving leaves into th W xe e jio 40 q of f these leava i are re s i 0 o pos or OF TO onUis abich axe are ei it i separating and drinking in ili ca bonic 1 h the millions of leavea which a single gingle I 1 t rap out and the constant of of tile the I 1 pioci 6 in in which they ahey are quo suspended enable i abe baut to draw an all al abundant laudant supply I 1 fora for all from i an all atmosphere oliero already adjusted to t diun ip ion of living auli animals nals this olista of r tile the leavec of plants is ona one 0 of 1 the ahe 0 nat 1 I 1 cies 14 by flip proportion gitig n or of I 1 it t the lip elwe jower r regions of f the atmosphere sphere is L A 1 teas ws t alian apu it vt Ls ill ii tile the higher Y regions egions I 1 0 S o also asaf abea watery vapor of ahda the aam atm 1 no less necessary f to the w 1 1 ok U the living plant polls r er to of mearly I 1 three fo fourths V r 0 wils nom from tile auri aco a of cs I 1 water I 1 Is s coyn lato the ilie airan air lita th alie fp of ui TI visible 41 16 vay II 11 were thi the I 1 air ibs absolutely 0 u pl y pry byj I 1 I 1 it would I 1 if ca ai I 1 water to eve evaporate fr from om avs ware korep I 1 tha it it could be supplied to them by 4 4 roos thus abe they would speedily liebo lecome go alm and tile hie whole I 1 plant wati would ld id dr droop wim 1 die I 1 I 1 I 1 as arg tile ig ancin fix m like manner ii 1 I 1 iier for tile the most part of wat water pT al il anan all oie red an and d fifty four ds wei glit r 11 t ill Is I 1 ho hundred pored and six sixteen teet pounds of water yater Q thirty eight pounds Q of f dry dri matter r m skin and from his lungs av water is co 11 11 1 evaporating weyo were ili the air around u lid joni r dry his skin inu wo would I 1 b become c p P parched arabe eda and I 1 ITAI 41 a X tand and would oppress cpr e as his fe feverish eri li fras P air which mau man tire thes f from 11 u PAS with moisture were re L at 1 bieh I J 0 I 1 I 1 e daj I 1 I 1 free from w walterj t k vor 1 ie he wwi cwi ap b breattie bre atlie the out the auids d s which fill up his t tji id would could dry u up into 0 awl a withered t li gred and anda ali 11 my ay tt it ii 19 because the I 1 khnom al sh nom aud and 10 i winds i C of if the desert depert i ato to tills a sj aja erpf ness nep th eliat at they tre re so fatal io tot abos bose 62 1 I 01 the aria waste thus the moisture mij I 1 sphere contains is essential to jo OR I 1 terance of 61 the present condition botlik lm I 1 and na VW vegetable t a ill e life ie I 1 1 S simple as the air appears its i I 1 a us 8 a 11 whole is somewhat c jojn TIVA T its several 8 substances involves 0 0 s tan par particulars ticul ars aad ad t he 46 ar yan m 1 L I 1 I 1 IV alieh ii the constant presence I 1 J e orl its eo essa ay I 1 pi sti tuenis I 1 is ase mcgie cured lofb at h 1 anlund aai qu 5 I 1 P wry yet yat we cannot fail jorri 0 I 1 fl ath a physical beauty and 11 I 1 wisp copt golip 0 ii 0 ahem ih em ay mbeni 0 benI astr of 0 li life I 1 iet |