,,! ,,int]national ,,sci5tific ,,s]ies4 ,,volume ,,vii4 ,,! ,,int]national ,,sci5tific ,,s]ies4 ,works already ,publi%$4 ,i4 ,,=ms ,,( ,,wat]1 ,,9 ,,cl\ds1 ,,ra91 ,,riv]s1 ,,ice1 ,,& ,,glaci]s4 ,by ,pr(4 ,,john ,,tyndall1 ,,ll4 ,d41 ,f4 ,r4 ,s4 #a vol4 ,clo?4 ,price1 #a4ej4 ,,ii4 ,,physics ,,& ,,politics2 ,,or1 ,,?\ghts ,,on ,,! ,,application ,,( ,,! ,,pr9ciples ,,( 8,,natural ,,selection0 ,,& 8,,inh]itance0 ,,to ,,political ,,society4 ,by ,,walt] ,,bagehot1 ,esq41 au?or ( 8,! ,engli% ,con/itution40 #a vol4 ,clo?4 ,price1 #a4ej4 ,,iii4 ,,foods4 ,by ,,edw>d ,,smi?1 ,m4 ,d41 ,,ll4 ,b41 ,f4 ,r4 ,s4 #a vol4 ,clo?4 ,price1 #a4ge4 ,,iv4 ,,m9d ,,& ,,body3 ,,! ,,!ories ,,( ,,_! ,,relations4 ,by ,,alex4 ,,ba91 ,,ll4 ,d41 ,pr(essor ( ,logic 9 ! ,univ]sity ( ,ab]de51 #a vol41 #abmo4 ,clo?4 ,price1 #a4ej4 ,v4 ,,! ,,/udy ,,( ,,sociology4 ,by ,,h]b]t ,,sp5c]4 ,price1 #a4ej4 ,,vi4 ,,! ,,new ,,*emi/ry4 ,by ,pr(4 ,,josiah ,p4 ,,cooke1 ,jr41 ( ,h>v>d ,univ]sity4 #a vol41 #abmo4 ,clo?4 ,price1 #b4jj4 ,,vii4 ,,! ,,cons]vation ,,( ,,en]gy4 ,by ,pr(4 ,,balf\r ,,/ew>t1 ,,ll4 ,d41 ,f4 ,r4 ,s4 #a vol41 #abmo4 ,clo?4 ,price1 #a4ej4 ,,viii4 ,,animal ,,locomotion2 ,,or1 ,,walk+1 ,,swimm+1 ,,& ,,fly+1 ,,) ,a ,,diss]tation ,,on ,a,,ronautics4 ,by ,j4 ,,bell ,,pettigrew1 ,m4 ,d41 ,f4 ,r4 ,s4 ,e41 ,f4 ,r4 ,c4 ,p4 ,e4 #a vol41 #abmo4 ,fully illu/rat$4 ,price1 #a4ge4 ,,ix4 ,,responsibility ,,9 ,,m5tal ,,disease4 ,by ,,h5ry ,,maudsley1 ,m4 ,d4 #a vol41 #abmo4 ,clo?4 ,price1 #a4ej4 ,x4 ,,! ,,sci5ce ,,( ,,law4 ,by ,pr(4 ,,%eldon ,,amos4 #a vol41 #abmo4 ,clo?4 ,price1 #a4ge4 ,,xi4 ,,animal ,,me*anism4 ,a ,,treatise ,,on ,,t]re/rial ,,& ,a,,rial ,,locomotion4 ,by ,e4 ,j4 ,,m>ey4 ,) #aag ,illu/rations4 ,price1 #a4ge4 ,,xii4 ,,! ,,hi/ory ,,( ,,! ,,conflict ,,betwe5 ,,religion ,,& ,,sci5ce4 ,by ,,john ,,wm4 ,,drap]1 ,m4 ,d41 ,,ll4 ,d41 au?or ( 8,! ,intellectual ,developm5t ( ,europe40 ,price1 #a4ge4 ,,xiii4 ,,! ,,doctr9e ,,( ,,desc5t1 ,,& ,,d>w9ism4 ,by ,pr(4 ,,osc> ,,s*midt1 ,/rasburg ,univ]sity4 ,price1 #a4ej4 ,,xiv4 ,,! ,,*emi/ry ,,( ,,light ,,& ,,photography4 ,,9 ,,its ,,application ,,to ,,art1 ,,sci5ce1 ,,& ,,indu/ry4 ,by ,dr4 ,,h]mann ,,vogel4 #ajj ,illu/rations4 ,price1 #b4jj4 ,,xv4 ,,fungi2 ,,_! ,,nature1 ,,influ5ce1 ,,& ,,uses4 ,by ,m4 ,c4 ,,cooke1 ,m4 ,a41 ,,ll4 ,d4 ,edit$ by ,rev4 ,m4 ,j4 ,,b]keley1 ,m4 ,a41 ,f4 ,l4 ,s4 ,) #aji ,illu/rations4 ,price1 #a4ej4 ,,xvi4 ,,! ,,life ,,& ,,gr[? ,,( ,,language4 ,by ,pr(4 ,w4 ,d4 ,,:itney1 ( ,yale ,college4 ,price1 #a4ej4 ,,xvii4 ,,! ,,nature ,,( ,,light1 ,,) ,a ,,g5]al ,,acc\nt ,,( ,,physical ,,optics4 ,by ,dr4 ,,eug5e ,,lommel1 ,pr(essor ( ,physics 9 ! ,univ]sity ( ,erlang54 ,) #ahh ,illu/rations & a ,plate ( ,spectra 9 ,*romo-li?ography4 7,9 press47 ,,! ,,int]national ,,sci5tific ,,s]ies4 ,,! ,,cons]vation ,,( ,,en]gy4 ,,by ,,balf\r ,,/ew>t1 ,,ll4 ,d41 ,f4,r4,s41 ,,pr(essor ,,( ,,natural ,,philosophy ,,at ,,! ,,ow5s ,,college1 ,,man*e/]4 ,,) ,,an ,,app5dix1 ,,treat+ ,,( ,,! ,,vital ,,& ,,m5tal ,,applications ,,( ,,! ,,doctr9e ,,new ,,york3 ,d4 ,,appleton ,,& ,,company1 #edi #eea ,,broadway4 #ahge4 ,,ent]$1 accord+ to ,act ( ,congress1 9 ! ye> #ahgd1 by ,d4 ,,appleton ,,company1 ,9 ! ,(fice ( ! ,libr>ian ( ,congress1 at ,wa%+ton4 ,,note ,,to ,,! ,,am]ican ,,edition4 ,! great prom95ce :i* ! mod]n doctr9e ( ! ,cons]vation ( ,en]gy or ,correlation ( ,=ces has lately assum$ 9 ! _w ( ?\ght1 has made a simple & popul> explanation ( ! subject v desirable4 ,! pres5t "w ( ,dr4 ,balf\r ,/ew>t1 contribut$ to ! ,int]national ,sci5tific ,s]ies1 fully meets ?is requirem5t1 z x is probably ! cle>e/ & mo/ elem5t>y /atem5t ( ! "q t has yet be5 attempt$4 ,simple 9 language1 copi\s & famili> 9 illu/ration1 & rem>kably lucid 9 ! pres5tation ( facts & pr9ciples1 8 little treatise =ms j ! introduction to ! great problem ( ! int]action ( natural =ces t is requir$ by g5]al read]s4 ,b ,pr(essor ,/ew>t hav+ conf9$ himself ma9ly to ! physical aspects ( ! subject1 x 0 desirable t 8 views %\ld be supplem5t$ by a /atem5t ( ! op]ation ( ! pr9ciple 9 ! sph]es ( life & m9d4 ,an ,app5dix has1 accord+ly1 be5 add$ to ! ,am]ican edition ( ,dr4 ,/ew>t's "w1 9 :i* ^! applications ( ! law are consid]$4 ,pr(essor ,joseph ,le ,conte publi%$ a v able essay f\rte5 ye>s ago on ! ,correlation ( ! ,physical & ,vital ,=ces1 :i* 0 ext5sively repr9t$ abroad1 & plac$ ! "n ( ! au?or among ! lead+ int]pret]s ( ! subject4 ,8 mode ( pres5t+ x 0 reg>d$ z peculi>ly happy1 & 0 widely adopt$ by o!r writ]s4 ,aft] fur!r inve/igations & m mature reflection1 he has rec5tly re/at$ 8 views1 & has k9dly furni%$ ! revis$ essay = ins]tion 9 ?is volume4 ,pr(essor ,a4 ,ba91 ! celebrat$ ,psy*ologi/ ( ,ab]de51 :o has done s mu* to advance ! /udy ( m9d 9 its physiological relations1 prep>$ an int]e/+ lecture n long ago on ! 8,correlation ( ! ,n]v\s & ,m5tal ,=ces10 :i* 0 read ) mu* int]e/ at ! "t ( its publication1 & is n[ repr9t$ z a suitable exposition ( t bran* ( ! subject4 ,^! two essays1 by c>ry+ out ! pr9ciple 9 ! field ( vital & m5tal ph5om5a1 w s]ve to give complet5ess & mu* great] value to ! pres5t volume4 ,,new ,,york1 ,decemb]1 #ahgc4 ,,preface4 ,we may reg>d ! ,univ]se 9 ! light ( a va/ physical ma*9e1 & our k ( x may be conv5i5tly divid$ into two bran*es4 ,! "o ( ^! embraces :at we "k reg>d+ ! /ructure ( ! ma*9e itself1 & ! o!r :at we "k reg>d+ its me?od ( work+4 ,x has appe>$ to ! au?or t1 9 a treatise l ?is1 ^! two bran*es ( k ought z mu* z possible to be /udi$ toge!r1 & he has !re=e endeavor$ to adopt ?is c\rse 9 ! foll[+ pages4 ,he has reg>d$ a univ]se compos$ ( atoms ) "s sort ( m$ium betwe5 !m z ! ma*9e1 & ! laws ( en]gy z ! laws ( work+ ( ?is ma*9e4 ,! fir/ *apt] embraces :at we "k reg>d+ atoms1 & gives also a def9ition ( ,en]gy4 ,! v>i\s =ces & en]gies ( ,nature are !reaft] enum]at$1 & ! law ( ,cons]vation is /at$4 ,!n foll[ ! v>i\s transmutations ( ,en]gy1 accord+ to a li/1 = :i* ! au?or is indebt$ to ,pr(4 ,tait4 ,! fif? *apt] gives a %ort hi/orical sket* ( ! subject1 end+ ) ! law ( ,dissipation2 :ile ! six? & la/ *apt] gives "s acc\nt ( ! position ( liv+ be+s 9 ?is univ]se ( ,en]gy4 ,b4 ,s4 ,! ,ow5s ,college1 ,man*e/]1 ,augu/1 #ahgc4 ,,cont5ts4 ,,note ,,to ,,! ,,am]ican ,,edition1 v ,,preface1 vii ,,*apt] ,i4--,,:at ,,is ,,en]gy8 #a ,,ii4--,,me*anical ,,en]gy ,,& ,,its ,,*ange ,,into ,,heat1 #bc ,,iii4--,,! ,,=ces ,,& ,,en]gies ,,( ,,nature3 ,,! ,,law ,,( ,,cons]vation1 #dh ,,iv4--,,transmutations ,,( ,,en]gy1 #hg ,v4--,,hi/orical ,,sket*3 ,,! ,,dissipation ,,( ,,en]gy1 #aca ,,vi4--,,! ,,position ,,( ,,life1 #aed ,,app5dix ,i4--,,correlation ,,( ,,vital ,,) ,,*emical ,,& ,,physical ,,=ces4 ,by ,,joseph ,,le ,,conte1 ,pr(essor ( ,geology & ,natural ,hi/ory 9 ! ,univ]sity ( ,cali=nia1 #aga ,,ii4--,,correlation ,,( ,,n]v\s ,,& ,,m5tal ,,=ces4 ,by ,,alex&] ,,ba91 ,pr(essor ( ,logic & ,m5tal ,philosophy 9 ! ,univ]sity ( ,ab]de51 #bje ,,! ,,cons]vation ,,( ,,en]gy4 ,,*apt] ,i4 ,,:at ,,is ,,en]gy8 ,our ,ignorance ( ,individuals4 #a4 ,v (t5 we "k little or no?+ ( individuals1 :ile we yet possess a def9ite k ( ! laws :i* regulate communities4 ,! ,regi/r>-,g5]al1 = example1 w tell u t ! dea?-rate 9 ,london v>ies ) ! temp]ature 9 su* a mann] t a v l[ temp]ature is inv>iably accompani$ by a v high dea?-rate4 ,b if we ask him to select "s "o individual1 & expla9 to u 9 :at mann] 8 dea? 0 caus$ by ! l[ temp]ature1 he w1 mo/ probably1 be unable to d s4 ,aga91 we may be q sure t aft] a bad h>ve/ !re w be a l>ge importation ( :eat into ! c\ntry1 :ile1 at ! same "t1 we are q ignorant ( ! individual j\rneys ( ! v>i\s p>ticles ( fl\r t g to make up a loaf ( bread4 ,or yet aga91 we "k t !re is a con/ant c>riage ( air f ! poles to ! equator1 z %[n by ! trade w9ds1 & yet no man is able to individualize a p>ticle ( ?is air1 & describe its v>i\s motions4 #b4 ,nor is our k ( individuals great] 9 ! doma9s ( physical sci5ce4 ,we "k no?+1 or next to no?+1 ( ! ultimate /ructure & prop]ties ( matt]1 :e!r organic or inorganic4 ,no d\bt !re are c]ta9 cases :]e a l>ge numb] ( p>ticles are l9k$ toge!r1 s z to act z "o individual1 & !n we c pr$ict its action--z1 = in/ance1 9 ! sol> sy/em1 :]e ! physical a/ronom] is able to =etell ) great exactness ! positions ( ! v>i\s planets1 or ( ! moon4 ,& s1 9 human affairs1 we f9d a l>ge numb] ( individuals act+ toge!r z "o nation1 & ! sagaci\s /atesman tak+ v mu* ! place ( ! sagaci\s a/ronom]1 ) reg>d to ! action & reaction ( v>i\s nations ^u "o ano!r4 ,b if we ask ! a/ronom] or ! /atesman to select an individual p>ticle & an individual human be+1 & pr$ict ! motions ( ea*1 we %all f9d t bo? w be completely at fault4 #c4 ,nor h we f> to look = ! cause ( _! ignorance4 ,a cont9u\s & re/less1 nay1 a v complicat$1 activity is ! ord] ( nature ?r\gh\t all h] individuals1 :e!r ^! be liv+ be+s or inanimate p>ticles ( matt]4 ,exi/5ce is1 9 tru?1 "o cont9u$ fight1 & a great battle is always & ev]y:]e rag+1 al?\gh ! field 9 :i* x is f\ght is (t5 completely %r\d$ f our view4 #d4 ,nev]!less1 al?\gh we _c trace ! motions ( individuals1 we may sometimes tell ! result ( ! fight1 & ev5 pr$ict h[ ! day w g1 z well z specify ! causes t contribute to br+ ab\t ! issue4 ,) great fre$om ( action & mu* complication ( motion 9 ! individual1 !re are yet comp>atively simple laws regulat+ ! jo9t result atta9able by ! community4 ,b1 be=e proce$+ to ^!1 x may n be out ( place to take a v brief survey ( ! organic & inorganic worlds1 9 ord] t our read]s1 z well z ourselves1 may realize our common ignorance ( ! ultimate /ructure & prop]ties ( matt]4 #e4 ,let u beg9 by ref]r+ to ! causes :i* br+ ab\t disease4 ,x is only v rec5tly t we h begun to suspect a l>ge numb] ( our diseases to be caus$ by organic g]ms4 ,n[1 assum+ t we are "r 9 ?is1 x mu/ nev]!less be confess$ t our ignorance ab\t ^! g]ms is mo/ complete4 ,x is p]haps d\btful :e!r we ev] saw "o ( ^! organisms1#a :ile x is c]ta9 t we are 9 pr(\nd ignorance ( _! prop]ties & habits4 ,we are told by "s writ]s#b t ! v air we brea! is absolutely teem+ ) g]ms1 & t we are surr\nd$ on all sides by an innum]able array ( m9ute organic be+s4 ,x has also be5 conjectur$ t !y are at incessant w>f>e among !mselves1 & t we =m ! spoil ( ! /rong] p>ty4 ,be ?is z x may1 we are at any rate intimately b\nd up )1 &1 s to speak1 at ! m]cy (1 a _w ( creatures1 ( :i* we "k z little z ( ! inhabitants ( ! planet ,m>s4 #f4 ,yet1 ev5 "h1 ) pr(\nd ignorance ( ! individual1 we are n altoge!r unacqua9t$ ) "s ( ! habits ( ^! p[]ful pr$atory communities4 ,?us we "k t *ol]a is em95tly a l[ level disease1 & t dur+ its ravages we ought to pay p>ticul> att5tion to ! wat] we dr9k4 ,?is is a g5]al law ( *ol]a1 :i* is ( ! m importance to u because we _c /udy ! habits ( ! individual organisms t cause ! disease4 ,c\ld we b see ^!1 & exp]im5t ^u !m1 we %\ld soon acquire a mu* m ext5sive k ( _! habits1 & p]haps f9d out ! means ( extirpat+ ! disease1 & ( prev5t+ its recurr5ce4 ,aga91 we "k 7?anks to ,j5n]7 t vacc9ation w prev5t ! ravages ( small-pox1 b 9 ?is in/ance we are no bett] (f ?an a b& ( captives :o h f\nd out 9 :at mann] to mutilate !mselves1 s z to r5d] !m un9t]e/+ to _! victori\s foe4 #g4 ,b if our k ( ! nature & habits ( organiz$ molecules be s small1 our k ( ! ultimate molecules ( inorganic matt] is1 if possible1 /ill small]4 ,x is only v rec5tly t ! lead+ m5 ( sci5ce h come to consid] _! v exi/5ce z a settl$ po9t4 ,9 ord] to realize :at is meant by an inorganic molecule1 let u take "s s& & gr9d x into small] & small] p>ticles1 & ^! aga9 into /ill small]4 ,9 po9t ( fact we %all nev] rea* ! sup]lative degree ( smallness by ?is op]ation--yet 9 our imag9ation we may suppose ! sub-division to be c>ri$ on cont9u\sly1 always mak+ ! p>ticles small] & small]4 ,9 ?is case we %\ld1 at la/1 come to an ultimate molecule ( s& or oxide ( silicon1 or1 9 o!r words1 we %\ld arrive at ! smalle/ entity reta9+ all ! prop]ties ( s&1 s t 7 x possible to divide ! molecule fur!r ! only result w\ld be to sep>ate x into its *emical con/itu5ts1 consi/+ ( silicon on ! "o side & oxyg5 on ! o!r4 ,we h1 9 tru?1 mu* reason to believe t s&1 or any o!r sub/ance1 is incapable ( inf9ite sub-division1 & t all we c d 9 gr9d+ d[n a solid lump ( any?+ is to r$uce x into lumps simil> to ! orig9al1 b only less 9 size1 ea* ( ^! small lumps conta9+ probably a great numb] ( individual molecules4 #h4 ,n[1 a drop ( wat] no less ?an a gra9 ( s& is built up ( a v great numb] ( molecules1 atta*$ to "o ano!r by ! =ce ( cohesion--a =ce :i* is mu* /rong] 9 ! s& ?an 9 ! wat]1 b :i* nev]!less exi/s 9 bo?4 ,&1 moreov]1 ,sir ,william ,?omson1 ! di/+ui%$ physici/1 has rec5tly arriv$ at ! foll[+ conclusion ) reg>d to ! size ( ! molecules ( wat]4 ,he imag9es a s+le drop ( wat] to be magnifi$ until x becomes z l>ge z ! e>?1 hav+ a diamet] ( #hjjj miles1 & all ! molecules to be magnifi$ 9 ! same proportion2 & he !n concludes t a s+le molecule w appe>1 "u ^! circum/ances1 z some:at l>g] ?an a %ot1 & some:at small] ?an a cricket ball4 #i4 ,:atev] be ! value ( ?is conclusion1 x enables u to realize ! exce$+ly small size ( ! individual molecules ( matt]1 & r5d]s x q c]ta9 t we %all nev]1 by means ( ! mo/ p[]ful microscope1 succe$ 9 mak+ visible ^! ultimate molecules4 ,= our k ( ! sizes1 %apes1 & prop]ties ( su* bodies1 we mu/ always1 !re=e1 be indebt$ to indirect evid5ce ( a v complicat$ nature4 ,x ?us appe>s t we "k little or no?+ ab\t ! %ape or size ( molecules1 or ab\t ! =ces :i* actuate !m2 &1 moreov]1 ! v l>ge/ masses ( ! univ]se %>e ) ! v smalle/ ?is prop]ty ( be+ beyond ! direct scrut9y ( ! human s5ses--! "o set because !y are s f> away1 & ! o!r because !y are s small4 #aj4 ,aga91 ^! molecules are n at re/1 b1 on ! contr>y1 !y display an int5se & ceaseless en]gy 9 _! motions4 ,!re is1 inde$1 an un9t]rupt$ w>f>e go+ on--a con/ant cla%+ toge!r ( ^! m9ute bodies1 :i* are cont9ually maim$1 & yet always recov] !mselves1 until1 p]haps1 "s bl[ is /ruck suffici5tly p[]ful to dissev] ! two or m simple atoms t g to =m a comp\nd molecule4 ,a new /ate ( ?+s !nce=w>d is ! result4 ,b a simple elem5t>y atom is truly an immortal be+1 & enjoys ! privilege ( rema9+ unalt]$ & ess5tially unaffect$ amid ! mo/ p[]ful bl[s t c be dealt aga9/ x--x is probably 9 a /ate ( ceaseless activity & *ange ( =m1 b x is nev]!less always ! same4 #aa4 ,n[1 a little reflection w conv9ce u t we h 9 ?is ceaseless activity ano!r b>ri] to an intimate acqua9tance ) molecules & atoms1 = ev5 if we c\ld see !m !y w\ld n rema9 at re/ suffici5tly long to enable u to scrut9ize !m4 ,no d\bt !re are devices by means ( :i* we c r5d] visible1 = in/ance1 ! patt]n ( a quickly revolv+ col\r$ disc1 = we may illum9ate x by a fla% ( electricity1 & ! disc may be suppos$ to be /ation>y dur+ ! extremely %ort "t ( ! fla%4 ,b we _c say ! same ab\t molecules & atoms1 =1 c\ld we see an atom1 & c\ld we illum9ate x by a fla% ( electricity1 ! atom w\ld mo/ probably h vibrat$ _m times dur+ ! exce$+ly small "t ( ! fla%4 ,9 f9e1 ! limits plac$ ^u our s5ses1 ) respect to space & "t1 equally preclude ! possibility ( our ev] becom+ directly acqua9t$ ) ^! exce$+ly m9ute bodies1 :i* are nev]!less ! raw mat]ials ( :i* ! :ole univ]se is built4 ,action & ,reaction1 ,equal & ,opposite4 #ab4 ,b :ile an imp5etrable veil is drawn ov] ! individual 9 ?is w>f>e ( cla%+ atoms1 yet we are n left 9 pr(\nd ignorance ( ! laws :i* det]m9e ! ultimate result ( all ^! motions1 tak5 toge!r z a :ole4 ,9 a ,vessel ( ,goldfi%4 ,let u suppose1 = in/ance1 t we h a glass globe conta9+ num]\s goldfi% /&+ on ! table1 & delicately pois$ on :eels1 s t ! slighte/ pu%1 ! "o way or ! o!r1 w\ld make x move4 ,^! goldfi% are 9 active & irregul> motion1 & he w\ld be a v bold man :o %\ld v5ture to pr$ict ! movem5ts ( an individual fi%4 ,b ( "o ?+ we may be q c]ta93 we may re/ assur$ t1 not)/&+ all ! irregul> motions ( its liv+ inhabitants1 ! globe conta9+ ! goldfi% w rema9 at re/ ^u its :eels4 ,ev5 if ! table 7 a lake ( ice1 & ! :eels 7 extremely delicate1 we %\ld f9d t ! globe w\ld rema9 at re/4 ,inde$1 we %\ld be exce$+ly surpris$ if we f\nd ! globe go+ away ( its own accord f ! "o side ( ! table to ! o!r1 or f ! "o side ( a %eet ( ice to ! o!r1 9 consequ5ce ( ! int]nal motions ( its inhabitants4 ,:atev] be ! motions ( ^! individual units1 yet we feel sure t ! globe _c move itself z a :ole4 ,9 su* a sy/em1 !re=e1 &1 inde$1 9 e sy/em left to itself1 !re may be /rong int]nal =ces act+ betwe5 ! v>i\s p>ts1 b ^! actions & reactions are equal & opposite1 s t :ile ! small p>ts1 :e!r visible or invisible1 are 9 viol5t commotion among !mselves1 yet ! sy/em z a :ole w rema9 at re/4 ,9 a ,rifle4 #ac4 ,n[ x is q a legitimate /ep to pass f ?is in/ance ( ! goldfi% to t ( a rifle t has j be5 fir$4 ,9 ! =m] case1 we imag9$ ! globe1 toge!r ) its fi%es1 to =m "o sy/em2 & 9 ! latt]1 we mu/ look ^u ! rifle1 ) its p[d] & ball1 z =m+ "o sy/em also4 ,let u suppose t ! explosion takes place ?r\gh ! application ( a sp>k4 ,al?\gh ?is sp>k is an ext]nal ag5t1 yet if we reflect a little we %all see t its only (fice 9 ?is case is to summon up ! int]nal =ces already exi/+ 9 ! load$ rifle1 & br+ !m into vigor\s action1 & t 9 virtue ( ^! int]nal =ces ! explosion takes place4 ,! mo/ prom95t result ( ?is explosion is ! out-ru% ( ! rifle ball ) a velocity t may1 p]haps1 c>ry x = ! be/ "p ( a mile be=e x comes to re/2 & "h x w\ld seem to u1 at fir/ sight1 t ! law ( equal action & reaction is c]ta9ly brok51 = ^! int]nal =ces pres5t 9 ! rifle h at lea/ propell$ "p ( ! sy/em1 namely1 ! rifle ball1 ) a mo/ enorm\s velocity 9 "o direction4 #ad4 ,b a little fur!r reflection w br+ to light ano!r ph5om5on besides ! out-ru% ( ! ball4 ,x is well kn[n to all sportsm5 t :5 a f[l+-piece is dis*>g$1 !re is a kick or recoil ( ! piece itself aga9/ ! %\ld] ( ! sportsman1 :i* he w\ld r get rid (1 b :i* we mo/ gladly welcome z ! solution ( our difficulty4 ,9 pla9 t]ms1 :ile ! ball is project$ =w>ds1 ! rifle /ock 7if free to move7 is at ! same mom5t project$ backw>ds4 ,to fix our ideas1 let u suppose t ! rifle /ock weighs #ajj ounces1 & ! ball "o ounce1 & t ! ball is project$ =w>ds ) ! velocity ( #ajjj feet p] second2 !n x is ass]t$1 by ! law ( action & reaction1 t ! rifle /ock is at ! same "t project$ backw>ds ) ! velocity ( #aj feet p] second1 s t ! mass ( ! /ock1 multipli$ by its velocity ( recoil1 %all precisely equal ! mass ( ! ball1 multipli$ by its velocity ( projection4 ,! "o product =ms a measure ( ! action 9 ! "o direction1 & ! o!r ( ! reaction 9 ! opposite direction1 & ?us we see t 9 ! case ( a rifle1 z well z 9 t ( ! globe ( fi%1 action & reaction are equal & opposite4 ,9 a ,fall+ ,/one4 #ae4 ,we may ev5 ext5d ! law to cases 9 :i* we d n p]ceive ! recoil or reaction at all4 ,?us1 if ,i drop a /one f ! top ( a precipice to ! e>?1 ! motion seems all to be 9 "o direction1 :ile at ! same "t x is 9 tru? ! result ( a mutual attraction betwe5 ! e>? & ! /one4 ,does n ! e>? move also8 ,we _c see x move1 b we are entitl$ to ass]t t x does 9 reality move upw>ds to meet ! /one1 al?\gh q to an imp]ceptible ext5t1 & t ! law ( action & reaction holds "h z truly z 9 a rifle1 ! only diff]5ce be+ t 9 ! "o case ! two objects are ru%+ toge!r1 :ile 9 ! o!r !y are ru%+ ap>t4 ,inasmu*1 h[ev]1 z ! mass ( ! e>? is v great comp>$ ) t ( ! /one1 x foll[s t its velocity mu/ be extremely small1 9 ord] t ! mass ( ! e>?1 multipli$ into its velocity upw>ds1 %all equal ! mass ( ! /one1 multipli$ into its velocity d[nw>ds4 #af4 ,we h ?us1 9 spite ( our ignorance ( ! ultimate atoms & molecules ( matt]1 arriv$ at a g5]al law :i* regulates ! action ( int]nal =ces4 ,we see t ^! =ces are always mutually ex]t$1 & t if ,a attracts or repels ,b1 ,b 9 its turn attracts or repels ,a4 ,we h "h1 9 fact1 a v good in/ance ( t k9d ( g5]alization1 :i* we may arrive at1 ev5 9 spite ( our ignorance ( individuals4 ,b hav+ n[ arriv$ at ?is law ( action & reaction1 d we "k all t x is desirable to "k8 h we got a complete und]/&+ ( :at takes place 9 all su* cases--= in/ance1 9 t ( ! rifle :i* is j dis*>g$8 ,let u consid] ?is po9t a little fur!r4 ,! ,rifle fur!r consid]$4 #ag4 ,we def9e quantity ( motion to mean ! product ( ! mass by ! velocity2 & s9ce ! velocity ( recoil ( ! rifle /ock1 multipli$ by ! mass ( ! /ock1 is equal to ! velocity ( projection ( ! rifle ball1 multipli$ by ! mass ( ! ball1 we conceive ourselves entitl$ to say t ! quantity ( motion1 or mom5tum1 g5]at$ is equal 9 bo? directions1 s t ! law ( action & reaction holds "h also4 ,nev]!less1 x _c b occur to u t1 9 "s s5se1 ! motion ( ! rifle ball is a v diff]5t ?+ f t ( ! /ock1 = x is "o ?+ to all[ ! /ock to recoil aga9/ y\r %\ld] & dis*>ge ! ball into ! air1 & a v diff]5t ?+ to dis*>ge ! ball aga9/ y\r %\ld] & all[ ! /ock to fly into ! air4 ,& if any man %\ld ass]t ! absolute equality betwe5 ! bl[ ( ! rifle /ock & t ( ! rifle ball1 y might reque/ him to put 8 ass]tion to ?is practical te/1 ) ! absolute c]ta9ty t he w\ld decl9e4 ,equality betwe5 ! two6--,impossible6 ,:y1 if ?is 7 ! case1 a company ( soldi]s engag$ 9 w> w\ld suff] mu* m ?an ! enemy aga9/ :om !y fir$1 = ! soldi]s w\ld c]ta9ly feel ea* recoil1 :ile ! enemy w\ld suff] f only a small proportion ( ! bullets4 ,! ,rifle ,ball possesses ,en]gy4 #ah4 ,n[1 :at is ! mean+ ( ?is great diff]5ce betwe5 ! two8 ,we h a vivid p]ception ( a mighty diff]5ce1 & x only rema9s = u to clo! our nak$ impressions 9 a prop]ly fitt+ sci5tific g>b4 ,! some?+ :i* ! rifle ball possesses 9 contradi/9ction to ! rifle /ock is cle>ly ! p[] ( ov]com+ resi/ance4 ,x c p5etrate ?r\gh oak wood or ?r\gh wat]1 or 7alas6 t x %\ld be s (t5 tri$7 ?r\gh ! human body1 & ?is p[] ( p5etration is ! di/+ui%+ *>act]i/ic ( a sub/ance mov+ ) v great velocity4 #ai4 ,let u def9e by ! t]m en]gy ?is p[] :i* ! rifle ball possesses ( ov]com+ ob/acles or ( do+ "w4 ,( c\rse we use ! ^w "w )\t ref]5ce to ! moral "* ( ! ?+ done1 & conceive ourselves entitl$ to sum up1 ) p]fect propriety & innoc5ce1 ! am\nt ( "w done 9 drill+ a hole ?r\gh a deal bo>d or ?r\gh a man4 #bj4 ,a body su* z a rifle ball1 mov+ ) v great velocity1 has1 !re=e1 en]gy1 & x requires v little consid]ation to p]ceive t ?is en]gy w be proportional to its weight or mass1 = a ball ( two ounces mov+ ) ! velocity ( #ajjj feet p] second w be ! same z two balls ( "o ounce mov+ ) ?is velocity1 b ! en]gy ( two simil>ly mov+ ounce balls w manife/ly be d\ble t ( "o1 s t ! en]gy is proportional to ! weight1 if we imag9e t1 mean:ile1 ! velocity rema9s ! same4 #ba4 ,b1 on ! o!r h&1 ! en]gy is n simply proportional to ! velocity1 =1 if x 71 ! en]gy ( ! rifle /ock & ( ! rifle ball w\ld be ! same1 inasmu* z ! rifle /ock w\ld ga9 z mu* by its sup]ior mass z x w\ld lose by its inf]ior velocity4 ,!re=e1 ! en]gy ( a mov+ body increases ) ! velocity m quickly ?an a simple proportion1 s t if ! velocity be d\bl$1 ! en]gy is m ?an d\bl$4 ,n[1 9 :at mann] does ! en]gy increase ) ! velocity8 ,t is ! "q we h n[ to answ]1 &1 9 do+ s1 we mu/ appeal to ! famili> facts ( ev]yday obs]vation & exp]i5ce4 #bb4 ,9 ! fir/ place1 x is well kn[n to artill]ym51 t if a ball h a d\ble velocity1 its p5etrat+ p[] or en]gy is increas$ ne>ly f\rfold1 s t x w pi]ce ?r\gh f\r1 or ne>ly f\r1 times z _m deal bo>ds z ! ball ) only a s+le velocity--9 o!r words1 !y w tell u 9 ma!matical language1 t ! en]gy v>ies z ! squ>e ( ! velocity4 ,def9ition ( ,"w4 #bc4 ,& n[1 be=e proce$+ fur!r1 x w be necess>y to tell our read]s h[ to measure "w 9 a /rictly sci5tific mann]4 ,we h def9$ en]gy to be ! p[] ( do+ "w1 & al?\gh e "o has a g5]al notion ( :at is meant by "w1 t notion may n be suffici5tly precise = ! purpose ( ?is volume4 ,h[1 !n1 are we to measure "w8 ,=tunately1 we h n f> to g = a practical means ( do+ ?is4 ,inde$1 !re is a =ce at h& :i* enables u to accompli% ?is measurem5t ) ! greate/ precision1 & ?is =ce is gravity4 ,n[1 ! fir/ op]ation 9 any k9d ( num]ical e/imate is to fix ^u our unit or /&>d4 ,?us we say a rod is s _m in*es long1 or a road s _m miles long4 ,"h an in* & a mile are *os5 z our /&>ds4 ,9 l mann]1 we speak ( s _m seconds1 or m9utes1 or h\rs1 or days1 or ye>s1 *oos+ t /&>d ( "t or duration :i* is mo/ conv5i5t = our purpose4 ,s 9 l mann] we mu/ *oose our unit ( "w1 b 9 ord] to d s we mu/ fir/ ( all *oose our units ( weight & ( l5g?1 & = ^! we w take ! kilogramme & ! metre1 ^! be+ ! units ( ! metrical sy/em4 ,! kilogramme corresponds to ab\t #ae1dcbce ,engli% gra9s1 be+ r m ?an two p\nds avoirdupois1 & ! metre to ab\t #cicga ,engli% in*es4 ,n[1 if we raise a kilogramme weight "o metre 9 v]tical height1 we are consci\s ( putt+ =? an ef=t to d s1 & ( be+ resi/$ 9 ! act by ! =ce ( gravity4 ,9 o!r words1 we sp5d en]gy & d "w 9 ! process ( rais+ ?is weight4 ,let u agree to consid] ! en]gy sp5t1 or ! "w done1 9 ?is op]ation z "o unit ( "w1 & let u call x ! kilogrammetre4 #bd4 ,9 ! next place1 x is v obvi\s t if we raise ! kilogramme two metres 9 height1 we d two units ( "w--if ?ree metres1 ?ree units1 & s on4 ,& aga91 x is equally obvi\s t if we raise a weight ( two kilogrammes "o metre high1 we likewise d two units ( "w1 :ile if we raise x two metres high1 we d f\r units1 & s on4 ,f ^! examples we are entitl$ to d]ive ! foll[+ rule3--,multiply ! weight rais$ 79 kilogrammes7 by ! v]tical height 79 metres7 ?r\gh :i* x is rais$1 & ! result w be ! "w done 79 kilogrammetres74 ,relation betwe5 ,velocity & ,en]gy4 #be4 ,hav+ ?us laid a num]ical f\ndation = our sup]/ructure1 let u next proce$ to inve/igate ! relation betwe5 velocity & en]gy4 ,b fir/ let u say a few words ab\t velocity4 ,?is is "o ( ! few cases 9 :i* ev]yday exp]i5ce w aid1 r ?an h9d]1 u 9 our sci5tific conception4 ,inde$1 we h con/antly be=e u ! example ( bodies mov+ ) v>iable velocities4 ,?us a railway tra9 is approa*+ a /ation & is j beg9n+ to slack5 its pace4 ,:5 we beg9 to obs]ve1 x is mov+ at ! rate ( =ty miles an h\r4 ,a m9ute aft]w>ds x is mov+ at ! rate ( tw5ty miles only1 & a m9ute aft] t x is at re/4 ,= no two consecutive mom5ts has ?is tra9 cont9u$ to move at ! same rate1 & yet we may say1 ) p]fect propriety1 t at su* a mom5t ! tra9 0 mov+1 say1 at ! rate ( ?irty miles an h\r4 ,we mean1 ( c\rse1 t _h x cont9u$ to move = an h\r ) ! spe$ :i* x _h :5 we made ! obs]vation1 x w\ld h gone ov] ?irty miles4 ,we "k t1 z a matt] ( fact1 x did n move = two seconds at t rate1 b ?is is ( no consequ5ce1 & h>dly at all int]f]es ) our m5tal grasp ( ! problem1 s accu/om$ are we all to cases ( v>iable velocity4 #bf4 ,let u n[ imag9e a kilogramme weight to be %ot v]tically upw>ds1 ) a c]ta9 initial velocity--let u say1 ) ! velocity ( #ih metres 9 "o second4 ,gravity w1 ( c\rse1 act aga9/ ! weight1 & cont9ually dim9i% its upw>d spe$1 j z 9 ! railway tra9 ! break 0 con/antly r$uc+ ! velocity4 ,b yet x is v easy to see :at is meant by an initial velocity ( #ih metres p] second2 x means t if gravity did n int]f]e1 & if ! air did n resi/1 &1 9 f9e1 if no ext]nal influ5ce ( any k9d 7 all[$ to act ^u ! asc5d+ mass1 x w\ld be f\nd to move ov] #ih metres 9 "o second4 ,n[1 x is well kn[n to ^? :o h /udi$ ! laws ( motion1 t a body1 %ot upw>ds ) ! velocity ( #ih metres 9 "o second1 w be br\ght to re/ :5 x has ris5 #di metres 9 height4 ,if1 !re=e1 x be a kilogramme1 its upw>d velocity w h enabl$ x to raise itself #di metres 9 height aga9/ ! =ce ( gravity1 or1 9 o!r words1 x w h done #di units ( "w2 & we may imag9e x1 :5 at ! top ( its asc5t1 & j ab\t to turn1 caught 9 ! h& & lodg$ on ! top ( a h\se1 in/ead ( be+ all[$ to fall aga9 to ! gr\nd4 ,we are1 !re=e1 entitl$ to say t a kilogramme1 %ot upw>ds ) ! velocity ( #ih metres p] second1 has en]gy equal to #di1 inasmu* z x c raise itself #di metres 9 height4 #bg4 ,let u next suppose t ! velocity ) :i* ! kilogramme is %ot upw>ds is t ( #aif metres p] second4 ,x is kn[n to all :o h /udi$ dynamics t ! kilogramme w n[ m\nt n only twice1 b f\r times z high z x did 9 ! la/ in/ance--9 o!r words1 x w n[ m\nt #aif metres 9 height4 ,evid5tly1 !n1 9 accordance ) our pr9ciples ( measurem5t1 ! kilogramme has n[ f\r times z mu* en]gy z x _h 9 ! la/ in/ance1 because x c raise itself f\r times z high1 & !re=e d f\r times z mu* "w1 & ?us we see t ! en]gy is increas$ f\r times by d\bl+ ! velocity4 ,_h ! initial velocity be5 ?ree times t ( ! fir/ in/ance1 or #bid metres p] second1 x might 9 l mann] be %[n t ! height atta9$ w\ld h be5 #dda metres1 s t by tripl+ ! velocity ! en]gy is increas$ n9e times4 #bh4 ,we ?us see t :e!r we measure ! en]gy ( a mov+ body by ! ?ickness ( ! planks ?r\gh :i* x c pi]ce its way1 or by ! height to :i* x c raise itself aga9/ gravity1 ! result arriv$ at is ! same4 ,we f9d ! en]gy to be proportional to ! squ>e ( ! velocity1 & we may =mul>ize our conclusion z foll[s3-- ,let v ! initial velocity express$ 9 metres p] second1 !n ! en]gy 9 kilogrammetres v_/#aif4 ,( c\rse1 if ! body %ot upw>ds weighs two kilogrammes1 !n ev]y?+ is d\bl$1 if ?ree kilogrammes1 tripl$1 & s on2 s t f9ally1 if we d5ote by m ! mass ( ! body 9 kilogrammes1 we %all h ! en]gy 9 kilogrammetres mv_/#aif4 ,to te/ ! tru? ( ?is =mula1 we h only to apply x to ! cases describ$ 9 ,arts4 #bf & #bg4 #bi4 ,we may fur!r illu/rate x by "o or two examples4 ,= in/ance1 let x be requir$ to f9d ! en]gy conta9$ 9 a mass ( five kilogrammes1 %ot upw>ds ) ! velocity ( #bj metres p] second4 ,"h we h m #e & v #bj1 h5ce-- ,en]gy #e7bj7_/7aif7 #bjjj_/7aif7 #ajbjd ne>ly4 ,aga91 let x be requir$ to f9d ! height to :i* ! mass ( ! la/ "q w asc5d be=e x /ops4 ,we "k t its en]gy is #ajbjd1 & t its mass is #e4 ,divid+ #ajbjd by #e1 we obta9 #bjdjh z ! height to :i* ?is mass ( five kilogrammes mu/ asc5d 9 ord] to d "w equal to #ajbjd kilogrammetres4 #cj4 ,9 :at we h said we h tak5 no acc\nt ei!r ( ! resi/ance or ( ! buoyancy ( ! atmosph]e2 9 fact1 we h suppos$ ! exp]im5ts to be made 9 vacuo1 or1 if n 9 vacuo1 made by means ( a heavy mass1 l lead1 :i* w be v little influ5c$ ei!r by ! resi/ance or buoyancy ( ! air4 ,we mu/ n1 h[ev]1 =get t if a %eet ( pap]1 or a fea!r1 be %ot upw>ds ) ! velocities m5tion$ 9 our text1 !y w c]ta9ly n rise 9 ! air to ne>ly ! height record$1 b w be mu* soon] br\ght to a /op by ! v great resi/ance :i* !y enc\nt] f ! air1 on acc\nt ( _! great surface1 comb9$ ) _! small mass4 ,on ! o!r h&1 if ! sub/ance we make use ( be a l>ge light bag fill$ ) hydrog51 x w f9d its way upw>ds )\t any ef=t on our "p1 & we %all c]ta9ly be do+ no "w by c>ry+ x "o or m metres 9 height--x w1 9 reality1 help to pull u up1 in/ead ( requir+ help f u to cause x to asc5d4 ,9 f9e1 :at we h said is meant to ref] to ! =ce ( gravity alone1 )\t tak+ into acc\nt a resi/+ m$ium su* z ! atmosph]e1 ! exi/5ce ( :i* ne$ n be consid]$ 9 our pres5t calculations4 #ca4 ,x %\ld likewise be rememb]$1 t :ile ! en]gy ( a mov+ body dep5ds ^u its velocity1 x is indep5d5t ( ! direction 9 :i* ! body is mov+4 ,we h suppos$ ! body to be %ot upw>ds ) a giv5 velocity1 b x might be %ot horizontally ) ! same velocity1 :5 x w\ld h precisely ! same en]gy z be=e4 ,a cannon ball1 if fir$ v]tically upw>ds1 may ei!r be made to sp5d its en]gy 9 rais+ itself1 or 9 pi]c+ ?r\gh a s]ies ( deal bo>ds4 ,n[1 if ! same ball be fir$ horizontally ) ! same velocity x w pi]ce ?r\gh ! same numb] ( deal bo>ds4 ,9 f9e1 direction ( motion is ( no consequ5ce1 & ! only reason :y we h *os5 v]tical motion is t1 9 ?is case1 !re is always ! =ce ( gravity /eadily & con/antly oppos+ ! motion ( ! body1 & enabl+ u to obta9 an accurate measure ( ! "w :i* x does by pi]c+ its way upw>ds aga9/ ?is =ce4 #cb4 ,b gravity is n ! only =ce1 & we might measure ! en]gy ( a mov+ body by ! ext5t to :i* x w\ld b5d a p[]ful spr+ or resi/ ! attraction ( a p[]ful magnet1 or1 9 f9e1 we might make use ( ! =ce :i* be/ suits our purpose4 ,if ?is =ce be a con/ant "o1 we mu/ measure ! en]gy ( ! mov+ body by ! space :i* x is able to trav]se aga9/ ! action ( ! =ce--j z1 9 ! case ( gravity1 we measur$ ! en]gy ( ! body by ! space ?r\gh :i* x 0 able to raise itself aga9/ its own weight4 #cc4 ,we mu/1 ( c\rse1 be> 9 m9d t if ?is =ce be m p[]ful ?an gravity1 a body mov$ a %ort di/ance aga9/ x w repres5t ! exp5diture ( z mu* en]gy z if x 7 mov$ a great] di/ance aga9/ gravity4 ,9 f9e1 we mu/ take acc\nt bo? ( ! /r5g? ( ! =ce & ( ! di/ance mov$ ov] by ! body aga9/ x be=e we c e/imate 9 an accurate matt] ! "w :i* has be5 done4 ,,footnotes3 #a ,x is said t !re are "o or two in/ances :]e ! microscope has enl>g$ !m into visibility4 #b ,see ,dr4 ,angus ,smi? on ,air & ,ra94 ,,*apt] ,,ii4 ,,me*anical ,,en]gy ,,& ,,its ,,*ange ,,into ,,heat4 ,en]gy ( ,position4 ,a ,/one high up4 #cd4 ,9 ! la/ *apt] x 0 %[n :at is meant by en]gy1 & h[ x dep5ds ^u ! velocity ( a mov+ body2 & n[ let u /ate t ?is same en]gy or p[] ( do+ "w may nev]!less be possess$ by a body absolutely at re/4 ,x w be rememb]$ 7,art4 #bf7 t 9 "o case :]e a kilogramme 0 %ot v]tically upw>ds1 we suppos$ x to be caught at ! summit ( its flight & lodg$ on ! top ( a h\se4 ,"h1 !n1 x re/s )\t motion1 b yet n )\t ! p[] ( do+ "w1 & h5ce n )\t en]gy4 ,= we "k v well t if we let x fall x w /rike ! gr\nd ) z mu* velocity1 &1 !re=e1 ) z mu* en]gy1 z x _h :5 x 0 orig9ally project$ upw>ds4 ,or we may1 if we *oose1 make use ( its en]gy to assi/ u 9 driv+ 9 a pile1 or utilize x 9 a multitude ( ways4 ,9 its l(ty position x is1 !re=e1 n )\t en]gy1 b ?is is ( a quiet nature1 & n due 9 ! lea/ to motion4 ,to :at1 !n1 is x due8 ,we reply--to ! position :i* ! kilogramme occupies at ! top ( ! h\se4 ,= j z a body 9 motion is a v diff]5t ?+ 7z reg>ds en]gy7 f a body at re/1 s is a body at ! top ( a h\se a v diff]5t ?+ f a body at ! bottom4 ,to illu/rate ?is1 we may suppose t two m5 ( equal activity & /r5g? are fight+ toge!r1 ea* hav+ 8 pile ( /ones ) :i* he is ab\t to belab\r 8 adv]s>y4 ,"o man1 h[ev]1 has secur$ = himself & 8 pile an elevat$ position on ! top ( a h\se1 :ile 8 enemy has to rema9 cont5t ) a position at ! bottom4 ,n[1 "u ^! circum/ances1 y c at once tell :i* ( ! two w ga9 ! day--evid5tly ! man on ! top ( ! h\se1 & yet n on acc\nt ( 8 own sup]ior en]gy1 b r on acc\nt ( ! en]gy :i* he d]ives f ! elevat$ position ( 8 pile ( /ones4 ,we ?us see t !re is a k9d ( en]gy d]iv$ f position1 z well z a k9d d]iv$ f velocity1 & we %all1 9 future1 call ! =m] en]gy ( position1 & ! latt] en]gy ( motion4 ,a ,head ( ,wat]4 #ce4 ,9 ord] to v>y our illu/ration1 let u suppose !re are two mills1 "o ) a l>ge pond ( wat] ne> x & at a high level1 :ile ! o!r has also a pond1 b at a l[] level ?an itself4 ,we ne$ h>dly ask :i* ( ! two is likely to "w--cle>ly ! "o ) ! pond at a l[ level c d]ive f x no advantage :atev]1 :ile ! o!r may use ! high level pond1 or head ( wat]1 z ?is is sometimes call$1 to drive its :eel1 & d its "w4 ,!re is1 ?us1 a great deal ( "w to be got out ( wat] high up--real sub/antial "w1 su* z gr9d+ corn or ?ra%+ x1 or turn+ wood or saw+ x4 ,on ! o!r h&1 !re is no "w at all to be got f a pond ( wat] t is l[ d[n4 ,a ,cross-b[ b5t4 ,a ,wat* w\nd up4 #cf4 ,9 bo? ( ! illu/rations n[ giv51 we h us$ ! =ce ( gravity z t =ce aga9/ :i* we are to d "w1 & 9 virtue ( :i* a /one high up1 or a head ( wat]1 is 9 a position ( advantage1 & has ! p[] ( do+ "w z x falls to a l[] level4 ,b !re are o!r =ces besides gravity1 &1 ) respect to ^!1 bodies may be 9 a position ( advantage & be able to d "w j z truly z ! /one1 or ! head ( wat]1 9 ! case be=e m5tion$4 ,let u take1 = in/ance1 ! =ce ( ela/icity1 & consid] :at happ5s 9 a cross-b[4 ,:5 ?is is b5t1 ! bolt is evid5tly 9 a position ( advantage ) reg>d to ! ela/ic =ce ( ! b[2 & :5 x is dis*>g$1 ?is en]gy ( position ( ! bolt is conv]t$ into en]gy ( motion1 j z1 :5 a /one on ! top ( a h\se is all[$ to fall1 its en]gy ( position is conv]t$ into t ( actual motion4 ,9 l mann] a wat* w\nd up is 9 a position ( advantage ) respect to ! ela/ic =ce ( ! ma9spr+1 & z ! :eels ( ! wat* move ?is is gradually conv]t$ into en]gy ( motion4 ,advantage ( ,position4 #cg4 ,x is1 9 fact1 ! fate ( all k9ds ( en]gy ( position to be ultimately conv]t$ into en]gy ( motion4 ,! =m] may be comp>$ to money 9 a bank1 or capital1 ! latt] to money :i* we are 9 ! act ( sp5d+2 & j z1 :5 we h money 9 a bank1 we c draw x out :5ev] we want x1 s1 9 ! case ( en]gy ( position1 we c make use ( x :5ev] we please4 ,to see ?is m cle>ly1 let u comp>e toge!r a wat]mill driv5 by a head ( wat]1 & a w9dmill driv5 by ! w9d4 ,9 ! "o case we may turn on ! wat] :5ev] x is mo/ conv5i5t = u1 b 9 ! o!r we mu/ wait until ! w9d happ5s to bl[4 ,! =m] has all ! indep5d5ce ( a ri* man2 ! latt]1 all ! obsequi\sness ( a poor "o4 ,if we pursue ! analogy a /ep fur!r1 we %all see t ! great capitali/1 or ! man :o has acquir$ a l(ty position1 is respect$ because he has ! disposal ( a great quantity ( en]gy2 & t :e!r he be a nobleman or a sov]eign1 or a g5]al 9 comm&1 he is p[]ful only f hav+ some?+ :i* enables him to make use ( ! s]vices ( o!rs4 ,:5 ! man ( weal? pays a lab\r+ man to "w = him1 he is 9 tru? conv]t+ s mu* ( 8 en]gy ( position into actual en]gy1 j z a mill] lets out a portion ( 8 head ( wat] 9 ord] to d "s "w by its means4 ,transmutations ( ,visible ,en]gy4--,a ,kilogramme %ot upw>ds4 #ch4 ,we h ?us endeav\r$ to %[ t !re is an en]gy ( repose z well z a liv+ en]gy1 an en]gy ( position z well z ( motion2 & n[ let u trace ! *anges :i* take place 9 ! en]gy ( a weight1 %ot v]tically upw>ds1 z x cont9ues to rise4 ,x />ts ) a c]ta9 am\nt ( en]gy ( motion1 b z x asc5ds1 ?is is by degrees *ang$ into t ( position1 until1 :5 x gets to ! top ( its flight1 its en]gy is entirely due to position4 ,to take an example1 let u suppose t a kilogramme is project$ v]tically upw>ds ) ! velocity ( #aif metres 9 "o second4 ,accord+ to ! =mula ( ,art4 #bh1 x conta9s #aif units ( en]gy due to its actual velocity4 ,if we exam9e x at ! end ( "o second1 we %all f9d t x has ris5 #adg metres 9 height1 & has n[ ! velocity ( #ih4 ,?is velocity we "k 7,art4 #bf7 d5otes an am\nt ( actual en]gy equal to #di1 :ile ! height rea*$ corresponds to an en]gy ( position equal to #adg4 ,! kilogramme has1 !re=e1 at ?is mom5t a total en]gy ( #aif1 ( :i* #adg units are due to position1 & #di to actual motion4 ,if we next exam9e x at ! end ( ano!r second1 we %all f9d t x has j be5 br\ght to re/1 s t its en]gy ( motion is nil2 nev]!less1 x has succe$$ 9 rais+ itself #aif metres 9 height1 s t its en]gy ( position is #aif4 ,!re is1 !re=e1 no disappe>ance ( en]gy dur+ ! rise ( ! kilogramme1 b m]ely a gradual *ange f "o k9d to ano!r4 ,x />ts ) actual en]gy1 & ?is is gradually *ang$ into t ( position2 b if1 at any /age ( its asc5t1 we add toge!r ! actual en]gy ( ! kilogramme1 & t due to its position1 we %all f9d t _! sum always rema9s ! same4 #ci4 ,precisely ! rev]se takes place :5 ! kilogramme beg9s its desc5t4 ,x />ts on its d[nw>d j\rney ) no en]gy ( motion :atev]1 b ) a c]ta9 am\nt ( en]gy ( position2 z x falls1 its en]gy ( position becomes less1 & its actual en]gy great]1 ! sum ( ! two rema9+ con/ant ?r\gh\t1 until1 :5 x is ab\t to /rike ! gr\nd1 its en]gy ( position has be5 entirely *ang$ into t ( actual motion1 & x n[ approa*es ! gr\nd ) ! velocity1 &1 !re=e1 ) ! en]gy1 :i* x _h :5 x 0 orig9ally project$ upw>ds4 ,! ,incl9$ ,plane4 #dj4 ,we h ?us trac$ ! transmutations1 z reg>ds en]gy1 ( a kilogramme %ot v]tically upw>ds1 & all[$ to fall aga9 to ! e>?1 & we may n[ v>y our hypo!sis by mak+ ! kilogramme rise v]tically1 b desc5d by means ( a smoo? incl9$ plane )\t friction--imag9e 9 fact1 ! kilogramme to be %ap$ l a ball or roll]1 & ! plane to be p]fectly smoo?4 ,n[1 x is well kn[n to all /ud5ts ( dynamics1 t 9 su* a case ! velocity :i* ! kilogramme has :5 x has rea*$ ! bottom ( ! plane w be equal to t :i* x w\ld h _h if x _h be5 dropp$ d[n v]tically ?r\gh ! same height1 & ?us1 by introduc+ a smoo? incl9$ plane ( ?is k9d1 y nei!r ga9 nor lose any?+ z reg>ds en]gy4 ,9 ! fir/ place1 y d n ga91 = ?9k :at w\ld happ5 if ! kilogramme1 :5 x rea*$ ! bottom ( ! incl9$ plane1 %\ld h a great] velocity ?an y gave x orig9ally1 :5 y %ot x up4 ,x w\ld evid5tly be a pr(itable ?+ to %oot up ! kilogramme v]tically1 & br+ x d[n by means ( ! plane1 = y w\ld get back m en]gy ?an y orig9ally sp5t ^u x1 & 9 e s5se y w\ld be a ga9]4 ,y might1 9 fact1 by means ( appropriate app>atus1 conv]t ! arrangem5t into a p]petual motion ma*9e1 & g on accumulat+ en]gy )\t limit--b ?is is n possible4 ,on ! o!r h&1 ! incl9$ plane1 unless x be r\gh & angul>1 w n rob y ( any ( ! en]gy ( ! kilogramme1 b w re/ore to y ! full am\nt1 :5 once ! bottom has be5 rea*$4 ,nor does x matt] :at be ! l5g? or %ape ( ! plane1 or :e!r x be /raight1 or curv$1 or spiral1 = 9 all cases1 if x only be smoo? & ( ! same v]tical height1 y w get ! same am\nt ( en]gy by caus+ ! kilogramme to fall f ! top to ! bottom4 #da4 ,b :ile ! en]gy rema9s ! same1 ! "t ( desc5t w v>y accord+ to ! l5g? & %ape ( ! plane1 = evid5tly ! kilogramme w take a long] "t to desc5d a v slop+ plane ?an a v /eep "o4 ,9 fact1 ! slop+ plane w take long] to g5]ate ! requisite velocity ?an ! /eep "o1 b bo? w h produc$ ! same result z reg>ds en]gy1 :5 once ! kilogramme has arriv$ at ! bottom4 ,functions ( a ,ma*9e4 #db4 ,our read]s are n[ beg9n+ to p]ceive t en]gy _c be creat$1 & t by no means c we coax or coz5 ,dame ,nature into giv+ u back m ?an we are entitl$ to get4 ,to impress ?is fundam5tal pr9ciple /ill m /rongly ^u our m9ds1 let u consid] 9 detail "o or two me*anical contrivances1 & see :at !y am\nt to z reg>ds en]gy4 ,illu/ration3 ,fig4 #a4 ,let u beg9 ) ! second sy/em ( pulleys4 ,"h we h a p[] ,p atta*$ to ! "o end ( a ?read1 :i* passes ov] all ! pulleys1 & is ultimately atta*$1 by its o!r extremity1 to a hook 9 ! upp] or fix$ block4 ,! weight ,w is1 on ! o!r h&1 atta*$ to ! l[] or moveable block1 & rises ) x4 ,let u suppose t ! pulleys are )\t weight & ! cords )\t friction1 & t ,w is support$ by six cords1 z 9 ! figure4 ,n[1 :5 !re is equilibrium 9 ?is ma*9e1 x is well kn[n t ,w w be equal to six times ,p2 t is to say1 a p[] ( "o kilogramme w1 9 su* a ma*9e1 balance or support a weight ( six kilogrammes4 ,if ,p be increas$ a s+le gra9 m1 x w ov]balance ,w1 & ,p w desc5d1 :ile ,w w beg9 to rise4 ,9 su* a case1 aft] ,p has desc5d$1 say six metres1 its weight be+1 say1 "o kilogramme1 x has lo/ a quantity ( en]gy ( position equal to six units1 s9ce x is at a l[] level by six metres ?an x 0 be=e4 ,we h1 9 fact1 exp5d$ ^u our ma*9e six units ( en]gy4 ,n[1 :at return h we receiv$ = ?is exp5diture8 ,our return is cle>ly ! rise ( ,w1 & me*anicians w tell u t 9 ?is case ,w w h ris5 "o metre4 ,b ! weight ( ,w is six kilogrammes1 & ?is hav+ be5 rais$ "o metre repres5ts an en]gy ( position equal to six4 ,we h ?us sp5t ^u our ma*9e1 9 ! fall ( ,p1 an am\nt ( en]gy equal to six units1 & obta9$ 9 ! rise ( ,w an equival5t am\nt equal to six units also4 ,we h1 9 tru?1 nei!r ga9$ nor lo/ en]gy1 b simply *ang$ x into a =m m conv5i5t = our use4 ,illu/ration3 ,fig4 #b4 #dc4 ,to impress ?is tru? /ill m /rongly1 let u take q a diff]5t ma*9e1 su* z ! hydro/atic press4 ,its mode ( action w be p]ceiv$ f ,fig4 #b4 ,"h we h two cyl9d]s1 a wide & a n>r[ "o1 :i* are connect$ toge!r at ! bottom by means ( a /rong tube4 ,ea* ( ^! cyl9d]s is provid$ ) a wat]-tight pi/on1 ! space b5ea? be+ fill$ ) wat]4 ,x is !re=e manife/1 s9ce ! two cyl9d]s are connect$ toge!r1 & s9ce wat] is incompressible1 t :5 we pu% d[n ! "o pi/on ! o!r w be pu%$ up4 ,let u suppose t ! area ( ! small pi/on is "o squ>e c5timetre1#c & t ( ! l>ge pi/on "o hundr$ squ>e c5timetres1 & let u apply a weight ( t5 kilogrammes to ! small] pi/on4 ,n[1 x is kn[n1 f ! laws ( hydro/atics1 t e squ>e c5timetre ( ! l>g] pi/on w be press$ upw>ds ) ! =ce ( t5 kilogrammes1 s t ! pi/on w altoge!r m\nt ) ! =ce ( #ajjj kilogrammes--t is to say1 x w raise a weight ( ?is am\nt z x asc5ds4 ,"h1 !n1 we h a ma*9e 9 virtue ( :i* a pressure ( t5 kilogrammes on ! small pi/on enables ! l>ge pi/on to rise ) ! =ce ( #ajjj kilogrammes4 ,b x is v easy to see t1 :ile ! small pi/on falls "o metre1 ! l>ge "o w only rise "o c5timetre4 ,= ! quantity ( wat] "u ! pi/ons be+ always ! same1 if ?is be pu%$ d[n "o metre 9 ! n>r[ cyl9d]1 x w only rise "o c5timetre 9 ! wide "o4 ,let u n[ consid] :at we ga9 by ?is ma*9e4 ,! p[] ( t5 kilogrammes appli$ to ! small] pi/on is made to fall ?r\gh "o metre1 & ?is repres5ts ! am\nt ( en]gy :i* we h exp5d$ ^u our ma*9e1 :ile1 z a return1 we obta9 #ajjj kilogrammes rais$ ?r\gh "o s+le c5timetre4 ,"h1 !n1 z 9 ! case ( ! pulleys1 ! return ( en]gy is precisely ! same z ! exp5diture1 &1 provid$ we ignore friction1 we nei!r ga9 nor lose any?+ by ! ma*9e4 ,all t we d is to transmute ! en]gy into a m conv5i5t =m--:at we ga9 9 p[] we lose 9 space2 b we are will+ to sacrifice space or quickness ( motion 9 ord] to obta9 ! trem5d\s pressure or =ce :i* we get by means ( ! hydro/atic press4 ,pr9ciple ( ,virtual ,velocities4 #dd4 ,^! illu/rations w h prep>$ our read]s to p]ceive ! true function ( a ma*9e4 ,?is 0 fir/ cle>ly def9$ by ,galileo1 :o saw t 9 any ma*9e1 no matt] ( :at k9d1 if we raise a l>ge weight by means ( a small "o1 x w be f\nd t ! small weight1 multipli$ into ! space ?r\gh :i* x is l[]$1 w exactly equal ! l>ge weight1 multipli$ into t ?r\gh :i* x is rais$4 ,?is pr9ciple1 kn[n z t ( virtual velocities1 enables u to p]ceive at once our true position4 ,we see t ! _w ( me*anism is n a manufactory1 9 :i* en]gy is creat$1 b r a m>t1 into :i* we may br+ en]gy ( "o k9d & *ange or b>t] x = an equival5t ( ano!r k9d1 t suits u bett]--b if we come ) no?+ 9 our h&1 ) no?+ we %all mo/ assur$ly return4 ,a ma*9e1 9 tru?1 does n create1 b only transmutes1 & ?is pr9ciple w enable u to tell1 )\t fur!r k ( me*anics1 :at are ! conditions ( equilibrium ( any arrangem5t4 ,= in/ance1 let x be requir$ to f9d ^? ( a lev]1 ( :i* ! "o arm is ?ree times z long z ! o!r4 ,"h x is evid5t t if we ov]balance ! lev] by a s+le gra91 s z to cause ! long arm ) its p[] to fall d[n :ile ! %ort "o ) its weight rises up1 !n ! long arm w fall ?ree in*es = e in* ?r\gh :i* ! %ort arm rises2 & h5ce1 to make up = ?is1 a s+le kilogramme on ! long arm w balance ?ree kilogrammes on ! %ort "o1 or ! p[] w be to ! weight z "o is to ?ree4 ,illu/ration3 ,fig4 #c4 #de4 ,or1 aga91 let u take ! incl9$ plane z repres5t$ 9 ,fig4 #c4 ,"h we h a smoo? plane & a weight held ^u x by means ( a p[] ,p1 z 9 ! figure4 ,n[1 if we ov]balance ,p by a s+le gra91 we %all br+ ! weight ,w f ! bottom to ! top ( ! plane4 ,b :5 ?is has tak5 place1 x is evid5t t ,p has fall5 ?r\gh a v]tical di/ance equal to ! l5g? ( ! plane1 :ile on ! o!r h& ,w has only ris5 ?r\gh a v]tical di/ance equal to ! height4 ,h5ce1 9 ord] t ! pr9ciple ( virtual velocities %all hold1 we mu/ h ,p multipli$ into its fall equal to ,w multipli$ into its rise1 t is to say1 ,p ,l5g? ( plane ,w ,height ( plane1 or ,p_/,w 7,height47_/7,l5g?47 ,:at ,friction does4 #df4 ,! two examples n[ giv5 are q suffici5t to enable our read]s to see ! true function ( a ma*9e1 & !y are n[ d\btless dispos$ to ackn[l$ge t no ma*9e w give back m en]gy ?an is sp5t ^u x4 ,x is n1 h[ev]1 equally cle> t x w n give back less2 inde$1 x is a well-kn[n fact t x con/antly does s4 ,= we h suppos$ our ma*9e to be )\t friction--b no ma*9e is )\t friction--& ! consequ5ce is t ! available out-come ( ! ma*9e is m or less dim9i%$ by ?is drawback4 ,n[1 unless we are able to see cle>ly :at "p friction really plays1 we _c prove ! cons]vation ( en]gy4 ,we see cle>ly en\gh t en]gy _c be creat$1 b we are n equally sure t x _c be de/roy$2 inde$1 we may say we h app>5t gr\nds = believ+ t x is de/roy$--t is our pres5t position4 ,n[1 if ! !ory ( ! cons]vation ( en]gy be true--t is to say1 if en]gy is 9 any s5se inde/ructible--friction w prove itself to be1 n ! de/roy] ( en]gy1 b m]ely ! conv]t] ( x into "s less app>5t & p]haps less useful =m4 #dg4 ,we mu/1 !re=e1 prep>e ourselves to /udy :at friction really does1 & also to recognize en]gy 9 a =m remote f t possess$ by a body 9 visible motion1 or by a head ( wat]4 ,to friction we may add p]cussion1 z a process by :i* en]gy is app>5tly de/roy$2 & z we h 7,art4 #ci7 consid]$ ! case ( a kilogramme %ot v]tically upw>ds1 demon/rat+ t x w ultimately rea* ! gr\nd ) an en]gy equal to t ) :i* x 0 %ot upw>ds1 we may pursue ! exp]im5t "o /ep fur!r1 & ask :at becomes ( its en]gy aft] x has /ruck ! gr\nd & come to re/8 ,we may v>y ! "q by ask+ :at becomes ( ! en]gy ( ! smi?'s bl[ aft] 8 hamm] has /ruck ! anvil1 or :at ( ! en]gy ( ! cannon ball aft] x has /ruck ! t>get1 or :at ( t ( ! railway tra9 aft] x has be5 /opp$ by friction at ! break-:eel8 ,all ^! are cases 9 :i* p]cussion or friction appe>s at fir/ sight to h de/roy$ visible en]gy2 b be=e pron\nc+ ^u ?is seem+ de/ruction1 x cle>ly behoves u to ask if any?+ else makes its appe>ance at ! mom5t :5 ! visible en]gy is app>5tly de/roy$4 ,=1 aft] all1 en]gy may be l ! ,ea/]n magicians1 ( :om we read t !y _h ! p[] ( *ang+ !mselves into a v>iety ( =ms1 b 7 nev]!less v c>eful n to disappe> altoge!r4 ,:5 ,motion is de/roy$1 ,heat appe>s4 #dh4 ,n[1 9 reply to ! "q we h put1 x may be confid5tly ass]t$ t :5ev] visible en]gy is app>5tly de/roy$ by p]cussion or friction1 some?+ else makes its appe>ance1 & t some?+ is heat4 ,?us1 a piece ( lead plac$ ^u an anvil may be greatly heat$ by successive bl[s ( a blacksmi?'s hamm]4 ,! collision ( fl9t & /eel w produce heat1 & a rapidly-mov+ cannon ball1 :5 /rik+ aga9/ an iron t>get1 may ev5 be heat$ to r$ness4 ,aga91 ) reg>d to friction1 we "k t on a d>k night sp>ks are se5 to issue f ! break-:eel :i* is /opp+ a railway tra91 & we "k1 also1 t ! axles ( railway c>riages get al>m+ly hot1 if !y are n well suppli$ ) grease4 ,f9ally1 ! s*oolboy w tell u t he is 9 ! habit ( rubb+ a brass button ^u ! desk1 & apply+ x to ! back ( 8 neighb\r's h&1 & t :5 8 own h& has be5 treat$ 9 ?is way1 he has f\nd ! button unmi/akeably hot4 ,heat a species ( ,motion4 #di4 ,= a long "t ?is appe>ance ( heat by friction or p]cussion 0 reg>d$ z inexplicable1 because x 0 believ$ t heat 0 a k9d ( matt]1 & x 0 difficult to und]/& :]e all ?is heat came f4 ,! p>tisans ( ! mat]ial hypo!sis1 no d\bt1 v5tur$ to sugge/ t 9 su* processes heat might be drawn f ! neighb\r+ bodies1 s t ! ,caloric 7:i* 0 ! "n giv5 to ! imag9>y sub/ance ( heat7 0 squeez$ or rubb$ out ( !m1 accord+ z ! process 0 p]cussion or friction4 ,b ?is 0 reg>d$ by _m z no explanation1 ev5 be=e ,sir ,humphry ,davy1 ab\t ! end ( la/ c5tury1 cle>ly %[$ x to be unt5able4 #ej4 ,davy's exp]im5ts consi/$ 9 rubb+ toge!r two pieces ( ice until x 0 f\nd t bo? 7 ne>ly melt$1 & he v>i$ ! conditions ( 8 exp]im5ts 9 su* a mann] z to %[ t ! heat produc$ 9 ?is case c\ld n be ab/ract$ f ! neighb\r+ bodies4 #ea4 ,let u pause to consid] ! alt]natives to :i* we are driv5 by ?is exp]im5t4 ,if we /ill *oose to reg>d heat z a sub/ance1 s9ce ?is has n be5 tak5 f ! surr\nd+ bodies1 x mu/ necess>ily h be5 creat$ 9 ! process ( friction4 ,b if we *oose to reg>d heat z a species ( motion1 we h a simpl] alt]native1 =1 inasmu* z ! en]gy ( visible motion has disappe>$ 9 ! process ( friction1 we may suppose t x has be5 trans=m$ into a species ( molecul> motion1 :i* we call heat2 & ?is 0 ! conclusion to :i* ,davy came4 #eb4 ,ab\t ! same "t ano!r philosoph] 0 occupi$ ) a simil> exp]im5t4 ,c\nt ,rum=d 0 sup]9t5d+ ! bor+ ( cannon at ! ars5al at ,muni*1 & 0 =cibly /ruck ) ! v great am\nt ( heat caus$ by ?is process4 ,! s\rce ( ?is heat appe>$ to him to be absolutely inexhau/ible1 &1 be+ unwill+ to reg>d x z ! creation ( a species ( matt]1 he 0 l$ l ,davy to attribute x to motion4 #ec4 ,assum+1 !re=e1 t heat is a species ( motion1 ! next po9t is to endeav\r to compreh5d :at k9d ( motion x is1 & 9 :at respects x is diff]5t f ord9>y visible motion4 ,to d ?is1 let u imag9e a railway c>riage1 full ( pass5g]s1 to be :irl+ along at a great spe$1 its occupants quietly at ease1 because1 al?\gh !y are 9 rapid motion1 !y are all mov+ at ! same rate & 9 ! same direction4 ,n[1 suppose t ! tra9 meets ) a sudd5 *eck2--a disa/] is ! consequ5ce1 & ! quiet placidity ( ! occupants ( ! c>riage is in/antly at an end4 ,ev5 if we suppose t ! c>riage is n brok5 up & its occupants kill$1 yet !y are all 9 a viol5t /ate ( excitem5t2 ^? front+ ! eng9e are driv5 ) =ce aga9/ _! opposite neighb\rs1 & are1 no d\bt1 z =cibly repell$1 ea* "o tak+ c>e ( himself 9 ! g5]al scramble4 ,n[1 we h only to sub/itute p>ticles = p]sons1 9 ord] to obta9 an idea ( :at takes place :5 p]cussion is conv]t$ into heat4 ,we h1 or suppose we h1 9 ?is act ! same viol5t collision ( atoms1 ! same ?ru/+ =w>d ( ,a ^u ,b1 & ! same viol5ce 9 pu%+ back on ! "p ( ,b--! same /ruggle1 confusion1 & excitem5t--! only diff]5ce be+ t p>ticles are heat$ in/ead ( human be+s1 or _! temp]s4 #ed4 ,we are b\nd to ackn[l$ge t ! pro( :i* we h n[ giv5 is n a direct "o2 inde$1 we h1 9 our fir/ *apt]1 expla9$ ! impossibility ( our ev] see+ ^! individual p>ticles1 or wat*+ _! movem5ts2 & h5ce our pro( ( ! ass]tion t heat consi/s 9 su* movem5ts _c possibly be direct4 ,we _c see t x does s consi/1 b yet we may feel sure1 z reasonable be+s1 t we are "r 9 our conjecture4 ,9 ! argum5t n[ giv51 we h only two alt]natives to />t )--ei!r heat mu/ consi/ ( a motion ( p>ticles1 or1 :5 p]cussion or friction is conv]t$ into heat1 a peculi> sub/ance call$ caloric mu/ be creat$1 = if heat be n a species ( motion x mu/ necess>ily be a species ( matt]4 ,n[1 we h pref]r$ to consid] heat z a species ( motion to ! alt]native ( suppos+ ! creation ( a peculi> k9d ( matt]4 #ee4 ,nev]!less1 x is desirable to h some?+ to say to an oppon5t :o1 r ?an ackn[l$ge heat to be a species ( motion1 w all[ ! creation ( matt]4 ,to su* an "o we w\ld say t innum]able exp]im5ts r5d] x c]ta9 t a hot body is n s5sibly heavi] ?an a cold "o1 s t if heat be a species ( matt] x is "o t is n subject to ! law ( gravity4 ,if we burn iron wire 9 oxyg5 gas1 we are entitl$ to say t ! iron comb9es ) ! oxyg51 because we "k t ! product is heavi] ?an ! orig9al iron by ! v am\nt :i* ! gas has lo/ 9 weight4 ,b !re is no su* pro( t dur+ combu/ion ! iron has comb9$ ) a sub/ance call$ caloric1 & ! abs5ce ( any su* pro( is en\gh to entitle u to consid] heat to be a species ( motion1 r ?an a species ( matt]4 ,heat a ,backw>d & ,=w>d ,motion4 #ef4 ,we %all n[ suppose t our read]s h ass5t$ to our proposition t heat is a species ( motion4 ,x is almo/ unnecess>y to add t x mu/ be a species ( backw>d & =w>d motion2 = no?+ is m cle> ?an t a heat$ sub/ance is n 9 motion z a :ole1 & w n1 if put ^u a table1 pu% its way f ! "o end to ! o!r4 ,ma!maticians express ?is peculi>ity by say+ t1 al?\gh !re is viol5t int]nal motion among ! p>ticles1 yet ! c5tre ( gravity ( ! sub/ance rema9s at re/2 & s9ce1 = mo/ purposes1 we may suppose a body to act z if conc5trat$ at its c5tre ( gravity1 we may say t ! body is at re/4 #eg4 ,let u "h1 be=e proce$+ fur!r1 borr[ an illu/ration f t bran* ( physics :i* treats ( s\nd4 ,suppose1 = in/ance1 t a man is accurately balanc$ 9 a scale-pan1 & t "s wat] ent]s 8 e>2 ( c\rse he w become heavi] 9 consequ5ce1 & if ! balance be suffici5tly delicate1 x w exhibit ! diff]5ce4 ,b suppose a s\nd or a noise ent]s 8 e>1 he may say ) tru? t some?+ has ent]$1 b yet t some?+ is n matt]1 nor w he become "o :it heavi] 9 consequ5ce ( its entrance1 & he w rema9 balanc$ z be=e4 ,n[1 a man into ^: e> s\nd has ent]$ may be comp>$ to a sub/ance into :i* heat has ent]$2 we may !re=e suppose a heat$ body to be simil> 9 _m respects to a s\nd+ body1 & j z ! p>ticles ( a s\nd+ body move backw>ds & =w>ds1 s we may suppose t ! p>ticles ( a heat$ body d ! same4 ,we %all take ano!r opportunity 7,art4 #afb7 to enl>ge ^u ?is lik5ess2 b1 mean:ile1 we %all suppose t our read]s p]ceive ! analogy4 ,me*anical ,equival5t ( ,heat4 #eh4 ,we h ?us come to ! conclusion t :5 any heavy body1 say a kilogramme weight1 /rikes ! gr\nd1 ! visible en]gy ( ! kilogramme is *ang$ into heat2 & n[1 hav+ e/abli%$ ! fact ( a relation%ip betwe5 ^! two =ms ( en]gy1 our next po9t is to asc]ta9 accord+ to :at law ! heat+ effect dep5ds ^u ! height ( fall4 ,let u1 = in/ance1 suppose t a kilogramme ( wat] is all[$ to drop f ! height ( #hdh metres1 & t we h ! means ( conf9+ to its own p>ticles & reta9+ !re ! heat+ effect produc$4 ,n[1 we may suppose t its desc5t is accompli%$ 9 two /ages2 t1 fir/ ( all1 x falls ^u a plat=m f ! height ( #dbd metres1 & gets heat$ 9 consequ5ce1 & t !n ! heat$ mass is all[$ to fall o!r #dbd metres4 ,x is cle> t ! wat] w n[ be d\bly heat$2 or1 9 o!r words1 ! heat+ effect 9 su* a case w be proportional to ! height ?r\gh :i* ! body falls--t is to say1 x w be proportional to ! actual en]gy :i* ! body possesses be=e ! bl[ has *ang$ ?is into heat4 ,9 fact1 j z ! actual en]gy repres5t$ by a fall f a height is proportional to ! height1 s is ! heat+ effect1 or molecul> en]gy1 into :i* ! actual en]gy is *ang$ proportional to ! height also4 ,hav+ e/abli%$ ?is po9t1 we n[ wi% to "k ?r\gh h[ _m metres a kilogramme ( wat] mu/ fall 9 ord] to be heat$ "o degree c5tigrade4 #ei4 ,= a precise det]m9ation ( ?is important po9t1 we are indebt$ to ,dr4 ,j\le1 ( ,man*e/]1 :o has1 p]haps1 done m ?an any "o else to put ! sci5ce ( en]gy ^u a sure f\ndation4 ,dr4 ,j\le made num]\s exp]im5ts1 ) ! view ( arriv+ at ! exact relation betwe5 me*anical en]gy & heat2 t is to say1 ( det]m9+ ! me*anical equival5t ( heat4 ,9 "s ( ! mo/ important ( ^! he took advantage ( ! friction ( fluids4 ,illu/ration3 ,fig4 #d4 #fj4 ,^! exp]im5ts 7 conduct$ 9 ! foll[+ mann]4 ,a c]ta9 fix$ weight 0 atta*$ to a pulley1 z 9 ! figure4 ,! weight _h1 ( c\rse1 a t5d5cy to desc5d1 & h5ce to turn ! pulley r\nd4 ,! pulley _h its axle support$ ^u friction :eels1 at f & f1 by means ( :i* ! friction caus$ by ! movem5t ( ! pulley 0 v mu* r$uc$4 ,a /r+1 pass+ ov] ! circumf]5ce ( ! pulley1 0 wrapp$ r\nd r1 s t1 z ! weight desc5d$1 ! pulley mov$ r\nd1 & ! /r+ ( ! pulley caus$ r to rotate v rapidly4 ,n[1 ! motion ( ! axis r 0 conduct$ )9 ! cov]$ box ,b1 :]e !re 0 atta*$ to r a sy/em ( paddles1 ( :i* a sket* is giv5 9 figure2 & !re=e1 z r mov$1 ^! paddles mov$ also4 ,!re 71 altoge!r1 eight sets ( ^! paddles revolv+ betwe5 f\r /ation>y vanes4 ,if1 !re=e1 ! box 7 full ( liquid1 ! paddles & ! vanes toge!r w\ld *urn x ab\t1 = ^! /ation>y vanes w\ld prev5t ! liquid be+ c>ri$ along by ! paddles 9 ! direction ( rotation4 ,n[1 9 ?is exp]im5t1 ! weight 0 made to desc5d ?r\gh a c]ta9 fix$ di/ance1 :i* 0 accurately measur$4 ,z x desc5d$1 ! paddles 7 set 9 motion1 & ! en]gy ( ! desc5d+ weight 0 ?us made to *urn1 & h5ce to heat "s wat] conta9$ 9 ! box ,b4 ,:5 ! weight _h desc5d$ a c]ta9 di/ance1 by undo+ a small peg p1 x c\ld be w\nd up aga9 )\t mov+ ! paddles 9 ,b1 & ?us ! heat+ effect ( sev]al falls ( ! weight c\ld be accumulat$ until ?is became s great z to be capable ( be+ accurately measur$ by a !rmomet]4 ,x ought to be m5tion$ t great c>e 0 tak5 9 ^! exp]im5ts1 n only to r$uce ! friction ( ! axles ( ! pulley z mu* z possible1 b also to e/imate & correct = ?is friction z accurately z possible2 9 fact1 e precaution 0 tak5 to make ! exp]im5t successful4 #fa4 ,o!r exp]im5ts 7 made by ,j\le1 9 "s ( :i* a disc 0 made to rotate aga9/ ano!r disc ( ca/-iron press$ aga9/ x1 ! :ole arrangem5t be+ imm]s$ 9 a ca/-iron vessel fill$ ) m]cury4 ,f all ^! exp]im5ts1 ,dr4 ,j\le conclud$ t ! quantity ( heat produc$ by friction1 if we c pres]ve & accurately measure x1 w always be f\nd proportional to ! quantity ( "w exp5d$4 ,he express$ ?is proportion by /at+ ! numb] ( units ( "w 9 kilogrammetres necess>y to raise by #a ,c4 ! temp]ature ( "o kilogramme ( wat]4 ,?is 0 #dbd1 z det]m9$ by 8 la/ & mo/ complete exp]im5ts2 & h5ce we may conclude t if a kilogramme ( wat] be all[$ to fall ?r\gh #dbd metres1 & if its motion be !n sudd5ly /opp$1 suffici5t heat w be g5]at$ to raise ! temp]ature ( ! wat] ?r\gh #a ,c41 & s on1 9 ! same proportion4 #fb4 ,n[1 if we take ! kilogrammetre z our unit ( "w1 & ! heat necess>y to raise a kilogramme ( wat] #a ,c4 z our unit ( heat1 ?is proportion may be express$ by say+ t "o heat unit is equal to #dbd units ( "w4 ,?is numb] is frequ5tly spok5 ( z ! me*anical equival5t ( heat2 & 9 sci5tific treatises x is d5ot$ by ,j41 ! initial ( ,dr4 ,j\le's "n4 #fc4 ,we h n[ /at$ ! exact relation%ip t subsi/s betwe5 me*anical en]gy & heat1 & be=e proce$+ fur!r ) pro(s ( ! great law ( cons]vation1 we %all endeav\r to make our read]s acqua9t$ ) o!r v>ieties ( en]gy1 on ! gr\nd t x is necess>y to p5etrate ! v>i\s disguises t our magician assumes be=e we c pret5d to expla9 ! pr9ciples t actuate him 9 8 trans=mations4 ,,footnotes3 #c ,t is to say1 a squ>e ! side ( :i* is "o c5timetre1 or ! hundr$? "p ( a metre4 ,,*apt] ,,iii4 ,,! ,,=ces ,,& ,,en]gies ,,( ,,nature3 ,,! ,,law ,,( ,,cons]vation4 #fd4 ,9 ! la/ *apt] we introduc$ our read]s to two v>ieties ( en]gy1 "o ( !m visible1 & ! o!r invisible or molecul>2 & x w n[ be our duty to se>* ?r\gh ! :ole field ( physical sci5ce = o!r v>ieties4 ,"h x is well to be> 9 m9d t all en]gy consi/s ( two k9ds1 t ( position & t ( actual motion1 & also t ?is di/9ction holds = invisible molecul> en]gy j z truly z x does = t :i* is visible4 ,n[1 en]gy ( position implies a body 9 a position ( advantage ) respect to "s =ce1 & h5ce we may ) propriety beg9 our se>* by inve/igat+ ! v>i\s =ces ( nature4 ,gravitation4 #fe4 ,! mo/ g5]al1 & p]haps ! mo/ important1 ( ^! =ces is gravitation1 & ! law ( action ( ?is =ce may be enunciat$ z foll[s3--,e p>ticle ( ! univ]se attracts e o!r p>ticle ) a =ce dep5d+ jo9tly ^u ! mass ( ! attract+ & ( ! attract$ p>ticle1 & v>y+ inv]sely z ! squ>e ( di/ance betwe5 ! two4 ,a little explanation w make ?is pla94 ,suppose a p>ticle or sy/em ( p>ticles ( :i* ! mass is unity to be plac$ at a di/ance equal to unity f ano!r p>ticle or sy/em ( p>ticles ( :i* ! mass is also unity--! two w attract ea* o!r4 ,let u agree to consid] ! mutual attraction betwe5 !m equal to unity also4 ,suppose1 n[1 t we h on ! "o side two su* sy/ems ) a mass repres5t$ by #b1 & on ! o!r side ! same sy/em z be=e1 ) a mass repres5t$ by unity1 ! di/ance1 mean:ile1 rema9+ unalt]$4 ,x is cle> ! d\ble sy/em w n[ attract ! s+le sy/em ) a tw(old =ce4 ,let u next suppose ! mass ( bo? sy/ems to be d\bl$1 ! di/ance always rema9+ ! same4 ,x is cle> t we %all n[ h a f\rfold =ce1 ea* unit ( ! "o sy/em attract+ ea* unit ( ! o!r4 ,9 l mann]1 if ! mass ( ! "o sy/em is #b1 & t ( ! o!r #c1 ! =ce w be #f4 ,we may1 = in/ance1 call ! compon5ts ( ! "o sy/em ,a#a1 ,a1 & ^? ( ! o!r ,a#c1 ,a#d1 ,a#e1 & we %all h ,a#a pull$ t[>ds ,a#c1 ,a#d1 & ,a#e1 ) a ?reefold =ce1 & ,a pull$ t[>ds ,a#c1 ,a#d1 & ,a#e1 ) a ?reefold =ce1 mak+ altoge!r a =ce equal to #f4 ,9 ! next place1 let ! masses rema9 unalt]$1 b let ! di/ance betwe5 !m be d\bl$1 !n ! =ce w be r$uc$ f\rfold4 ,let ! di/ance be tripl$1 !n ! =ce w be r$uc$ n9efold1 & s on4 #ff4 ,gravitation may be describ$ z a v weak =ce1 capable ( act+ at a di/ance1 or at lea/ ( appe>+ to d s4 ,x takes ! mass ( ! :ole e>? to produce ! =ce ) :i* we are s famili> at its surface1 & ! pres5ce ( a l>ge mass ( rock or m\nta9 does n produce any appreciable diff]5ce 9 ! weight ( any sub/ance4 ,x is ! gravitation ( ! e>?1 less5$ ( c\rse by di/ance1 :i* acts ^u ! moon #bdj1jjj miles away1 & ! gravitation ( ! sun influ5ces 9 l mann] ! e>? & ! v>i\s o!r planets ( our sy/em4 ,ela/ic ,=ces4 #fg4 ,ela/ic =ces1 al?\gh 9 _! mode ( action v diff]5t f gravity1 are yet due to visible arrangem5ts ( matt]2 ?us1 :5 a cross-b[ is b5t1 !re is a visible *ange produc$ 9 ! b[1 :i*1 z a :ole1 resi/s ?is b5d+1 & t5ds to resume its previ\s position4 ,x !re=e requires en]gy to b5d a b[1 j z truly & visibly z x does to raise a weight above ! e>?1 & ela/icity is1 !re=e1 z truly a species ( =ce z gravity is4 ,we %all n "h attempt to discuss ! v>i\s ways 9 :i* ?is =ce may act1 or 9 :i* a solid ela/ic sub/ance w resi/ all attempts to de=m x2 b 9 all cases x is cle>ly manife/ t "w mu/ be sp5t ^u ! body1 & ! =ce ( ela/icity mu/ be enc\nt]$ & ov]come ?r\gh\t a c]ta9 space be=e any s5sible de=mation c take place4 ,=ce ( ,cohesion4 #fh4 ,let u n[ leave ! =ces :i* animate l>ge masses ( matt]1 & proce$ to discuss ^? :i* subsi/ betwe5 ! small] p>ticles ( :i* ^! l>ge masses are compos$4 ,& "h we mu/ say "o ^w m ab\t molecules & atoms1 & ! di/9ction we feel ourselves entitl$ to draw betwe5 ^! v small bodies1 ev5 al?\gh we %all nev] be able to see ei!r ! "o or ! o!r4 ,9 our fir/ *apt] 7,art4 #g7 we suppos$ ! cont9ual sub-division ( a gra9 ( s& until we _h arriv$ at ! smalle/ entity reta9+ all ! prop]ties ( s&--?is we call$ a molecule1 & no?+ small] ?an ?is is entitl$ to be call$ s&4 ,if we cont9ue ?is sub-division fur!r1 ! molecule ( s& sep>ates itself into its *emical con/itu5ts1 consi/+ ( silicon on ! "o side1 & oxyg5 on ! o!r4 ,?us we arrive at la/ at ! smalle/ body :i* c call itself silicon1 & ! smalle/ :i* c call itself oxyg51 & we h no reason to suppose t ei!r ( ^! is capable ( sub-division into some?+ else1 s9ce we reg>d oxyg5 & silicon z elem5t>y or simple bodies4 ,n[1 ^! con/itu5ts ( ! silicon molecule are call$ atoms1 s t we say ! s& molecule is divisible into atoms ( silicon & ( oxyg54 ,fur!rmore1 we h /rong reason = suppos+ t su* molecules & atoms really exi/1 b into ! argum5ts = _! exi/5ce we _c n[ ent]--x is "o ( ^? ?+s t we mu/ ask our read]s to take = grant$4 #fi4 ,let u n[ take two molecules ( s&4 ,^!1 :5 ne> toge!r1 h a v /rong attraction = ea* o!r4 ,x is1 9 tru?1 ?is attraction :i* r5d]s x difficult to break up a cry/all9e p>ticle ( s& or rock cry/al4 ,b x is only ex]t$ :5 ! molecules are ne> en\gh toge!r to =m a homog5e\s cry/all9e /ructure1 = let ! di/ance betwe5 !m be some:at increas$1 & we f9d t all attraction entirely vani%es4 ,?us !re is little or no attraction betwe5 diff]5t p>ticles ( s&1 ev5 al?\gh !y are v closely pack$ toge!r4 ,9 l mann]1 ! integrity ( a piece ( glass is due to ! attraction betwe5 its molecules2 b let ^! be sep>at$ by a flaw1 & x w soon be f\nd t ?is v small increase ( di/ance greatly dim9i%es ! attraction betwe5 ! p>ticles1 & t ! /ructure w n[ fall to pieces f ! slighte/ cause4 ,n[1 ^! examples are suffici5t to %[ t molecul> attraction or cohesion1 z ?is is call$1 is a =ce :i* acts v p[]fully ?r\gh a c]ta9 small di/ance1 b :i* vani%es altoge!r :5 ?is di/ance becomes p]ceptible4 ,cohesion is /ronge/ 9 solids1 :ile 9 liquids x is mu* dim9i%$1 & 9 gases x may be said to vani% altoge!r4 ,! molecules ( gases are1 9 tru?1 s f> away f "o ano!r1 z to h little or no mutual attraction1 a fact prov$ by ,dr4 ,j\le1 ^: "n 0 m5tion$ 9 ! la/ *apt]4 ,=ce ( ,*emical ,aff9ity4 #gj4 ,let u n[ consid] ! mutual =ces betwe5 atoms4 ,^! may be *>act]iz$ z ev5 /rong] ?an ! =ces betwe5 molecules1 b z disappe>+ /ill m rapidly :5 ! di/ance is increas$4 ,let u1 = in/ance1 take c>bon & oxyg5--two sub/ances :i* are ready to comb9e toge!r to =m c>bonic acid1 :5ev] !y h a suitable opportunity4 ,9 ?is case1 ea* atom ( c>bon w unite ) two ( oxyg51 & ! result w be some?+ q diff]5t f ei!r4 ,yet "u ord9>y circum/ances c>bon1 or its repres5tative1 coal1 w rema9 un*ang$ 9 ! pres5ce ( oxyg51 or ( atmosph]ic air conta9+ oxyg54 ,!re w be no t5d5cy to comb9e toge!r1 because al?\gh ! p>ticles ( ! oxyg5 w\ld appe> to be 9 imm$iate contact ) ^? ( ! c>bon1 yet ! ne>ness is n suffici5t to p]mit ( *emical aff9ity act+ ) advantage4 ,:51 h[ev]1 ! ne>ness becomes suffici5t1 !n *emical aff9ity beg9s to op]ate4 ,we h1 9 fact1 ! famili> act ( combu/ion1 &1 z its consequ5ce1 ! *emical union ( ! c>bon or coal ) ! oxyg5 ( ! air1 c>bonic acid be+ ! result4 ,"h1 !n1 we h a v p[]ful =ce act+ only at a v small di/ance1 :i* we "n *emical aff9ity1 inasmu* z x repres5ts ! attraction ex]t$ betwe5 atoms ( diff]5t bodies 9 contradi/9ction to cohesion1 :i* d5otes ! attraction betwe5 molecules ( ! same body4 #ga4 ,if we reg>d gravitation z ! repres5tative ( =ces t act or appe> to act1 at a di/ance1 we may reg>d cohesion & *emical aff9ity z ! repres5tatives ( ^? =ces :i*1 al?\gh v p[]ful1 only act or appe> to act ?r\gh a v small int]val ( di/ance4 ,a little reflection w %[ u h[ inconv5i5t x w\ld be if gravitation dim9i%$ v rapidly ) ! di/ance2 = !n ev5 suppos+ t ! bond :i* reta9s u to ! e>? 7 to hold good1 t :i* reta9s ! moon to ! e>? might vani% entirely1 z well z t :i* reta9s ! e>? to ! sun1 & ! consequ5ces w\ld be f> f pleasant4 ,reflection w also %[ u h[ inconv5i5t x w\ld be if *emical aff9ity exi/$ at all di/ances2 if coal1 = in/ance1 7 to comb9e ) oxyg5 )\t ! application ( heat1 x w\ld greatly alt] ! value ( ?is fuel to mank9d1 & w\ld mat]ially *eck ! progress ( human indu/ry4 ,rem>ks on ,molecul> & ,atomic ,=ces4 #gb4 ,n[1 x is important to rememb] t we mu/ treat cohesion & *emical aff9ity exactly 9 ! same way z gravity has be5 treat$2 & j z we h en]gy ( position ) respect to gravity1 s may we h z truly a species ( en]gy ( position ) respect to cohesion & *emical aff9ity4 ,let u beg9 ) cohesion4 #gc4 ,we h hi!rto reg>d$ heat z a peculi> motion ( ! molecules ( matt]1 )\t any ref]5ce to ! =ce :i* actuates ^! molecules4 ,b x is a well-kn[n fact t bodies 9 g5]al exp& :5 heat$1 s t1 9 virtue ( ?is expansion1 ! molecules ( a body are driv5 viol5tly ap>t aga9/ ! =ce ( cohesion4 ,"w has 9 tru? be5 done aga9/ ?is =ce1 j z truly z1 :5 a kilogramme is rais$ f ! e>?1 "w is done aga9/ ! =ce ( gravity4 ,:5 a sub/ance is heat$1 we may1 !re=e1 suppose t ! heat has a tw(old (fice to p]=m1 "p ( x go+ to increase ! actual motions ( ! molecules1 & "p ( x to sep>ate ^! molecules f "o ano!r aga9/ ! =ce ( cohesion4 ,?us1 if ,i sw+ r\nd horizontally a weight 7atta*$ to my h& by an ela/ic ?read ( india-rubb]71 my en]gy w be sp5t 9 two ways--fir/ ( all1 x w be sp5t 9 communicat+ a velocity to ! weight2 &1 secondly1 9 /ret*+ ! india-rubb] /r+1 by means ( ! c5trifugal t5d5cy ( ! weight4 ,"w w be done aga9/ ! ela/ic =ce ( ! /r+1 z well z sp5t 9 increas+ ! motion ( ! weight4 ,n[1 some?+ ( ?is k9d may be tak+ place :5 a body is heat$1 = we may v well suppose heat to consi/ ( a v]tical or circul> motion1 ! t5d5cy ( :i* w\ld be to drive ! p>ticles asund] aga9/ ! =ce ( cohesion4 ,"p1 !re=e1 ( ! en]gy ( heat w be sp5t 9 augm5t+ ! motion1 & "p 9 driv+ asund] ! p>ticles4 ,we may1 h[ev]1 suppose t1 9 ord9>y cases1 ! great proportion ( ! en]gy ( heat goes t[>ds increas+ ! molecul> motion1 r ?an 9 do+ "w aga9/ ! =ce ( cohesion4 #gd ,9 c]ta9 cases1 h[ev]1 x is probable t ! great] "p ( ! heat appli$ is sp5t 9 do+ "w aga9/ molecul> =ces1 in/ead ( increas+ ! motions ( molecules4 ,?us1 :5 a solid melts1 or :5 a liquid is r5d]$ gase\s1 a consid]able am\nt ( heat is sp5t 9 ! process1 :i* does n become s5sible1 t is to say1 does n affect ! !rmomet]4 ,?us1 9 ord] to melt a kilogramme ( ice1 heat is requir$ suffici5t to raise a kilogramme ( wat] ?r\gh #hj ,c41 & yet1 :5 melt$1 ! wat] is no w>m] ?an ! ice4 ,we express ?is fact by say+ t ! lat5t heat ( wat] is #hj4 ,aga91 if a kilogramme ( wat] at #ajj be conv]t$ entirely into /eam1 z mu* heat is requir$ z w\ld raise ! wat] ?r\gh #ecg ,c41 or #ecg kilogrammes ( wat] ?r\gh "o degree2 b yet ! /eam is no hott] ?an ! wat]1 & we express ?is fact by say+ t ! lat5t heat ( /eam is #ecg4 ,n[1 9 bo? ( ^! in/ances x is at lea/ extremely probable t a l>ge portion ( ! heat is sp5t 9 do+ "w aga9/ ! =ce ( cohesion2 &1 m especially1 :5 a fluid is conv]t$ into a gas1 we "k t ! molecules are 9 t process sep>at$ s f> f "o ano!r z to lose entirely any trace ( mutual =ce4 ,we may1 !re=e1 conclude t al?\gh 9 mo/ cases ! great] portion ( ! heat appli$ to a body is sp5t 9 increas+ its molecul> motion1 & only a small "p 9 do+ "w aga9/ cohesion1 yet :5 a solid melts1 or a liquid vaporizes1 a l>ge portion ( ! heat requir$ is n improbably sp5t 9 do+ "w aga9/ molecul> =ces4 ,b ! en]gy1 ?\gh sp5t1 is n lo/1 = :5 ! liquid aga9 freezes1 or :5 ! vap\r aga9 cond5ses1 ?is en]gy is once m trans=m$ into ! %ape ( s5sible heat1 j z :5 a /one is dropp$ f ! top ( a h\se1 its en]gy ( position is trans=m$ once m into actual en]gy4 #ge4 ,a s+le in/ance w suffice to give our read]s a notion ( ! /r5g? ( molecul> =ces4 ,if a b> ( wr\ght iron1 ^: temp]ature is #aj ,c4 above t ( ! surr\nd+ m$ium1 be tightly secur$ at its extremities1 x w draw ^! toge!r ) a =ce ( at lea/ "o ton = ea* squ>e in* ( section4 ,9 "s cases :]e a build+ has %[n signs ( bulg+ outw>ds1 iron b>s h be5 plac$ across x1 & secur$ :ile 9 a heat$ /ate to ! walls4 ,on cool+1 ! iron contract$ ) great =ce1 & ! walls 7 !reby pull$ toge!r4 #gf4 ,we are next br\ght to consid] atomic =ces1 or ^? :i* lead to *emical union1 & n[ let u see h[ ^! are influ5c$ by heat4 ,we h se5 t heat causes a sep>ation betwe5 ! molecules ( a body1 t is to say1 x increases ! di/ance betwe5 two contigu\s molecules1 b we mu/ n suppose t1 mean:ile1 ! molecules !mselves are left unalt]$4 ,! t5d5cy ( heat to cause sep>ation is n conf9$ to increas+ ! di/ance betwe5 molecules1 b acts also1 no d\bt1 9 increas+ ! di/ance betwe5 p>ts ( ! same molecule3 9 fact1 ! en]gy ( heat is sp5t 9 pull+ ! con/itu5t atoms asund] aga9/ ! =ce ( *emical aff9ity1 z well z 9 pull+ ! molecules asund] aga9/ ! =ce ( cohesion1 s t1 at a v high temp]ature1 x is probable t mo/ *emical comp\nds w\ld be decompos$1 & _m are s1 ev5 at a v mod]ate heat4 ,?us ! attraction betwe5 oxyg5 & silv] is s slight t at a comp>atively l[ temp]ature ! oxide ( silv] is decompos$4 ,9 l mann]1 lime/one1 or c>bonate ( lime1 is decompos$ :5 subject$ to ! heat ( a lime-kiln1 c>bonic acid be+ giv5 (f1 :ile quick-lime rema9s beh9d4 ,n[1 9 sep>at+ het]og5e\s atoms aga9/ ! p[]ful =ce ( *emical aff9ity1 "w is done z truly z x is 9 sep>at+ molecules f "o ano!r aga9/ ! =ce ( cohesion1 or 9 sep>at+ a /one f ! e>? aga9/ ! =ce ( gravity4 #gg4 ,heat1 z we h se51 is v frequ5tly influ5tial 9 p]=m+ ?is sep>ation1 & its en]gy is sp5t 9 s do+2 b o!r en]getic ag5ts produce *emical decomposition z well z heat4 ,= in/ance1 c]ta9 rays ( ! sun decompose c>bonic acid into c>bon & oxyg5 9 ! leaves ( plants1 & _! en]gy is sp5t 9 ! process2 t is to say1 x is sp5t 9 pull+ asund] two su* p[]fully attract+ sub/ances aga9/ ! aff9ity !y h = "o ano!r4 ,&1 aga91 ! electric curr5t is able to decompose c]ta9 sub/ances1 & ( c\rse its en]gy is sp5t 9 ! process4 ,!re=e1 :5ev] two p[]fully attract+ atoms are sep>at$1 en]gy is sp5t 9 caus+ ?is sep>ation z truly z 9 sep>at+ a /one f ! e>?1 & :5 once ! sep>ation has be5 accompli%$ we h a species ( en]gy ( position j z truly z we h 9 a head ( wat]1 or 9 a /one at ! top ( a h\se4 #gh4 ,x is ?is *emical sep>ation t is meant :5 we speak ( coal z a s\rce ( en]gy4 ,coal1 or c>bon1 has a great attraction = oxyg51 & :5ev] heat is appli$ ! two bodies unite toge!r4 ,n[ oxyg51 z x exi/s 9 ! atmosph]e1 is ! common inh]itance ( all1 & if1 9 addition to ?is1 "s ( u possess coal 9 our cell>s1 or 9 pits1 we h ?us secur$ a /ore ( en]gy ( position :i* we c draw ^u ) m facility ?an if x 7 a head ( wat]1 =1 al?\gh we c draw ^u ! en]gy ( a head ( wat] :5ev] we *oose1 yet we _c c>ry x ab\t ) u f place to place z we c ) coal4 ,we ?us p]ceive t x is n ! coal1 by itself1 t =ms ! s\rce ( en]gy1 b ?is is due to ! fact t we h coal1 or c>bon1 9 "o place1 & oxyg5 9 ano!r1 :ile we h also ! means ( caus+ !m to unite ) ea* o!r :5ev] we wi%4 ,if !re 7 no oxyg5 9 ! air1 coal by itself w\ld be ( no value4 ,electricity3 its ,prop]ties4 #gi4 ,our read]s h n[ be5 told ab\t ! =ce ( cohesion t exi/s betwe5 molecules ( ! same body1 & also ab\t t ( *emical aff9ity exi/+ betwe5 atoms ( diff]5t bodies4 ,n[1 het]og5eity is an ess5tial elem5t ( ?is latt] =ce--!re mu/ be a diff]5ce ( "s k9d be=e x c exhibit itself--& "u ^! circum/ances its exhibitions are frequ5tly *>act]iz$ by v extraord9>y & int]e/+ ph5om5a4 ,we allude to t peculi> exhibition aris+ out ( ! =ces ( het]og5e\s bodies :i* we call electricity1 &1 be=e proce$+ fur!r1 x may n be out ( place to give a %ort sket* ( ! mode ( action ( ?is v my/]i\s1 b mo/ int]e/+1 ag5t4 #hj4 ,! sci5ce ( electricity is ( v anci5t orig92 b its beg9n+ 0 v small4 ,= a c\ple ( ?\s& ye>s x made little or no progress1 & !n1 dur+ ! c\rse ( little m ?an a c5tury1 develop$ into ! giant :i* x n[ is4 ,! anci5t ,greeks 7 aw>e t amb]1 :5 rubb$ ) silk1 _h ! prop]ty ( attract+ light bodies2 & ,dr4 ,gilb]t1 ab\t ?ree hundr$ ye>s ago1 %[$ t _m o!r ?+s1 su* z sulphur1 seal+-wax1 & glass1 h ! same prop]ty z amb]4 ,9 ! progress ( ! sci5ce x came to be kn[n t c]ta9 sub/ances are able to c>ry away ! peculi> influ5ce produc$1 :ile o!rs are unable to d s2 ! =m] are call$ conductors1 & ! latt] non-conductors1 or insulators1 ( electricity4 ,to make ! di/9ction app>5t1 let u take a metal rod1 hav+ a glass /em atta*$ to x1 & rub ! glass /em ) a piece ( silk1 c>e be+ tak5 t bo? silk & glass are w>m & dry4 ,we %all f9d t ! glass has n[ acquir$ ! prop]ty ( attract+ little bits ( pap]1 or eld] pi?2 b only :]e x has be5 rubb$1 = ! peculi> influ5ce acquir$ by ! glass has n be5 able to spread itself ov] ! surface4 ,if1 h[ev]1 we take hold ( ! glass /em1 & rub ! metal rod1 we may1 p]haps1 produce ! same prop]ty 9 ! metal1 b x w spread ov] ! :ole1 n conf9+ itself to ! "p rubb$4 ,?us we p]ceive t metal is a conductor1 :ile glass is an insulator1 or non-conductor1 ( electricity4 ,illu/ration3 ,fig4 #e4 #ha4 ,we w\ld next obs]ve t ?is influ5ce is ( two k9ds4 ,to prove ?is1 let u p]=m ! foll[+ exp]im5t4 ,let u susp5d a small pi? ball by a v sl5d] silk ?read1 z 9 ,fig4 #e4 ,next1 let u rub a /ick ( w>m1 dry glass ) a piece ( w>m silk1 & ) ?is excit$ /ick t\* ! pi? ball4 ,! pi? ball1 aft] be+ t\*$1 w be repell$ by ! excit$ glass4 ,let u next excite1 9 a simil> mann]1 a /ick ( dry seal+-wax ) a piece ( w>m1 dry flannel1 & on approa*+ ?is /ick to ! pi? ball x w attract x1 al?\gh ! ball1 9 its pres5t /ate1 is repell$ by ! excit$ glass4 ,?us a pi? ball1 t\*$ by excit$ glass1 is repell$ by excit$ glass1 b attract$ by excit$ seal+-wax4 ,9 l mann]1 x might be %[n t a pi? ball1 t\*$ by excit$ seal+-wax1 w be aft]w>ds repell$ by excit$ seal+-wax1 b attract$ by excit$ glass4 ,n[1 :at ! excit$ glass did to ! pi? ball1 0 to communicate to x "p ( its own influ5ce1 aft] :i* ! ball 0 repell$ by ! glass2 or1 9 o!r words1 bodies *>g$ ) simil> electricities repel "o ano!r4 ,aga91 s9ce ! pi? ball1 :5 *>g$ ) ! electricity f glass1 0 attract$ to ! electrifi$ seal+-wax1 we conclude t bodies *>g$ ) unlike electricities attract "o ano!r4 ,! electricity f glass is sometimes call$ vitre\s1 & t f seal+-wax res9\s1 electricity1 b m frequ5tly ! =m] is kn[n z positive1 & ! latt] z negative1 electricity--x be+ und]/ood t ^! words d n imply ! possession ( a positive nature by ! "o influ5ce1 or ( a negative nature by ! o!r1 b are m]ely t]ms employ$ to express ! app>5t antagonism :i* exi/s betwe5 ! two k9ds ( electricity4 #hb4 ,! next po9t wor?y ( notice is t :5ev] "o electricity is produc$1 j z mu* is produc$ ( an opposite description4 ,?us1 9 ! case ( glass excit$ by silk1 we h positive electricity develop$ ^u ! glass1 :ile we h also negative electricity develop$ ^u ! silk to precisely ! same ext5t4 ,&1 aga91 :5 seal+-wax is rubb$ ) flannel1 we h negative electricity develop$ ^u ! seal+-wax1 & j z mu* positive ^u ! flannel4 #hc4 ,^! facts h giv5 rise to a !ory ( electricity1 or at lea/ to a me?od ( reg>d+ x1 :i*1 if n absolutely correct1 seems yet to unite toge!r ! v>i\s ph5om5a4 ,accord+ to ?is hypo!sis1 a neutral1 unexcit$ body is suppos$ to conta9 a /ore ( ! two electricities comb9$ toge!r1 s t :5ev] su* a body is excit$1 a sep>ation is produc$ betwe5 ! two4 ,! ph5om5a :i* we h describ$ are1 !re=e1 due to ?is electrical sep>ation1 & inasmu* z ! two electricities h a great aff9ity = "o ano!r1 x requires ! exp5diture ( en]gy to produce ?is sep>ation1 j z truly z x does to sep>ate a /one f ! e>?4 #hd4 ,n[1 x is wor?y ( note t electrical sep>ation is only produc$ :5 het]og5e\s bodies are rubb$ toge!r4 ,?us1 if flannel be rubb$ ^u glass1 we h electricity2 b if flannel be rubb$ ^u glass cov]$ ) flannel1 we h none4 ,9 l mann]1 if silk be rubb$ ^u seal+-wax cov]$ ) silk1 or1 9 f9e1 if two portions ( ! same sub/ance be rubb$ toge!r1 we h no electricity4 ,on ! o!r h&1 a v slight diff]5ce ( texture is sometimes suffici5t to produce electrical sep>ation4 ,?us1 if two pieces ( ! same silk ribbon be rubb$ toge!r l5g?wise1 we h no electricity2 b if !y be rubb$ across ea* o!r1 ! "o is positively1 & ! o!r negatively1 electrifi$4 ,9 fact1 ?is elem5t ( het]og5eity is an all important "o 9 electrical developm5t1 & ?is leads u to conjecture t electrical attraction may probably be reg>d$ z peculi>ly alli$ to t =ce :i* we call *emical aff9ity4 ,at any rate1 electricity & *emical aff9ity are only manife/$ betwe5 bodies t are1 9 "s respects1 dissimil>4 #he4 ,! foll[+ is a li/ ( bodies arrang$ accord+ to ! electricity :i* !y develop :5 rubb$ toge!r1 ea* sub/ance be+ positively electrifi$ :5 rubb$ ) any sub/ance b5ea? x 9 ! li/4 #a4 ,cat's sk94 #b4 ,flannel4 #c4 ,ivory4 #d4 ,glass4 #e4 ,silk4 #f4 ,wood4 #g4 ,%ellac4 #h4 ,res94 #i4 ,metals4 #aj4 ,sulphur4 #aa4 ,ca\t*\c4 #ab4 ,gutta-p]*a4 #ac4 ,gun-cotton4 ,?us1 if res9 be rubb$ ) cat's sk91 or ) flannel1 ! cat's sk9 or flannel w be positively1 & ! res9 negatively1 electrifi$2 :ile if glass be rubb$ ) silk1 ! glass w be positively1 & ! silk negatively1 electrifi$1 & s on4 #hf4 ,x is n our purpose "h to describe at l5g? ! electrical ma*9e1 b we may /ate t x consi/s ( two p>ts1 "o = g5]at+ electricity by means ( ! friction ( a rubb] aga9/ glass1 & ano!r consi/+ ( a sy/em ( brass tubes1 ( consid]able surface1 support$ on glass /ems1 = collect+ & reta9+ ! electricity s produc$4 ,?is latt] "p ( ! ma*9e is call$ its prime conductor4 ,electric ,induction4 ,illu/ration3 ,fig4 #f4 #hg4 ,let u n[ suppose t we h set 9 action a ma*9e ( ?is k9d1 & accumulat$ a consid]able quantity ( positive electricity 9 its prime conductor at ,a4 ,let u next take two vessels1 ,b & ,c1 made ( brass1 support$ on glass /ems4 ,^! two vessels are suppos$ to be 9 contact1 b at ! same "t to be capable ( be+ sep>at$ f "o ano!r at _! middle po9t1 :]e ! l9e is drawn 9 ,fig4 #f4 ,n[ let u cause ,b & ,c to approa* ,a toge!r4 ,at fir/1 ,b & ,c are n electrifi$1 t is to say1 _! two electricities are n sep>at$ f ea* o!r1 b are mix$ toge!r2 b m>k :at w happ5 z !y are pu%$ t[>ds ,a4 ,! positive electricity ( ,a w decompose ! two electricities ( ,b & ,c1 attract+ ! negative t[>ds itself1 & repell+ ! positive z f> away z possible4 ,! disposition ( electricities w1 !re=e1 be z 9 ! figure4 ,if we n[ pull ,c away f ,b1 we h obta9$ a quantity ( positive electricity on ,c1 by help ( ! orig9al electricity :i* 0 9 ,a2 9 fact1 we h made use ( ! orig9al /ock or electrical capital 9 ,a1 9 ord] to obta9 positive electricity 9 ,c1 )\t1 h[ev]1 dim9i%+ ! am\nt ( our orig9al /ock4 ,n[1 ?is di/ant action or help1 r5d]$ by ! orig9al electricity 9 sep>at+ t ( ,b & ,c1 is call$ electric induction4 #hh4 ,! exp]im5t may1 h[ev]1 be p]=m$ 9 a some:at diff]5t mann]--we may all[ ,b & ,c to rema9 toge!r1 & gradually pu% !m ne>] to ,a4 ,z ,b & ,c approa* ,a1 ! sep>ation ( _! electricities w become great] & great]1 until1 :5 ,a & ,b are only divid$ by a small ?ickness ( air1 ! two opposite electricities !n accumulat$ w h suffici5t /r5g? to ru% toge!r ?r\gh ! air1 & unite ) ea* o!r by means ( a sp>k4 #hi4 ,! pr9ciple ( induction may be us$ ) advantage1 :5 x is wi%$ to accumulate a l>ge quantity ( electricity4 ,illu/ration3 ,fig4 #g4 ,9 ?is case1 an in/rum5t call$ a ,leyd5 j> is v frequ5tly employ$4 ,x consi/s ( a glass j>1 coat$ inside & outside ) t9 foil1 z 9 ,fig4 #g4 ,a brass rod1 hav+ a knob at ! end ( x1 is connect$ metallically ) ! inside coat+1 & is kept 9 its place by be+ pass$ ?r\gh a cork1 :i* cov]s ! m\? ( ! j>4 ,we h ?us two metallic coat+s :i* are n electrically connect$ ) "o ano!r4 ,n[1 9 ord] to *>ge a j> ( ?is k9d1 let ! outside coat+ be connect$ by a *a9 ) ! e>?1 :ile at ! same "t positive electricity f ! prime conductor ( an electrical ma*9e is communicat$ to ! inside knob4 ,! positive electricity w accumulate on ! inside coat+ ) :i* ! knob is connect$4 ,x w !n decompose ! two electricities ( ! outside coat+1 driv+ ! positive electricity to ! e>?1 & !re dissipat+ x1 b attract+ ! negative to itself4 ,!re w ?us be positive electricity on ! inside1 & negative on ! outside coat+4 ,^! two electricities may be comp>$ to two ho/ile armies wat*+ ea* o!r1 & v anxi\s to get toge!r1 :ile1 h[ev]1 !y are sep>at$ f "o ano!r by means ( an insurm\ntable ob/acle4 ,!y w ?us rema9 fac+ ea* o!r1 & at _! po/s1 :ile ea* side is1 mean:ile1 be+ recruit$ by ! same op]ation z be=e4 ,we may by ?is means accumulate a va/ quantity ( opposite electricities on ! two coat+s ( su* a j>1 & !y w rema9 !re = a long "t1 especially if ! surr\nd+ atmosph]e & ! glass surface ( ! j> be q dry4 ,:51 h[ev]1 electric connection ( any k9d is made betwe5 ! two coat+s1 ! electricities ru% toge!r & unite ) "o ano!r 9 ! %ape ( a sp>k1 :ile if ! human body be ! in/rum5t ( connect+ !m a sev]e %ock w be felt4 #ij4 ,x w\ld ?us appe> t1 :5 two bodies *>g$ ) opposite electricities are br\ght ne> ea* o!r1 ! two electricities ru% toge!r1 =m+ a curr5t1 & ! ultimate result is a sp>k4 ,n[1 ?is sp>k implies heat1 & is1 9 tru?1 no?+ else ?an small p>ticles ( int5sely heat$ matt] ( "s k9d4 ,we h "h1 !re=e1 fir/ ( all1 ! conv]sion ( electrical sep>ation into a curr5t ( electricity1 &1 secondly1 ! conv]sion ( ?is curr5t into heat4 ,9 ?is case1 h[ev]1 ! curr5t la/s only a v small "t2 ! dis*>ge1 z x is call$1 ( a ,leyd5 j> be+ probably accompli%$ 9 ? ( a second4 ,! ,electric ,curr5t4 #ia4 ,9 o!r cases we h electrical curr5ts :i*1 al?\gh n s p[]ful z t produc$ by dis*>g+ a ,leyd5 j>1 yet la/ long]1 & are1 9 fact1 cont9u\s in/ead ( mom5t>y4 ,we may see a simil> diff]5ce 9 ! case ( visible en]gy4 ,?us we might1 by means ( gunp[d]1 s5d up 9 a mom5t an enorm\s mass ( wat]2 or we might1 by means ( a f\nta91 s5d up ! same mass 9 ! c\rse ( "t1 & 9 a v mu* quiet] mann]4 ,we h ! same sort ( diff]5ce 9 electrical dis*>ges1 & hav+ spok5 ( ! ru%+ toge!r ( two opposite electricities by means ( an explosion & a sp>k1 let u n[ speak ( ! em95tly quiet & effective voltaic curr5t1 9 :i* we h a cont9u\s com+ toge!r ( ! same two ag5ts4 ,illu/ration3 ,fig4 #h4 #ib4 ,x is n our object "h to give a complete description1 ei!r hi/orical or sci5tific1 ( ! voltaic batt]y1 b r to give su* an acc\nt z w enable our read]s to und]/& :at ! arrangem5t is1 & :at sort ( effect x produces2 & ) ?is object we %all at once proce$ to describe ! batt]y ( ,grove1 :i* is p]haps ! mo/ efficaci\s ( all ! v>i\s arrangem5ts = ! purpose ( produc+ an electric curr5t4 ,9 ?is batt]y we h a numb] ( cells connect$ toge!r1 z 9 ,fig4 #h1 :i* %[s a batt]y ( ?ree cells4 ,ea* cell consi/s ( two vessels1 an out] & an inn] "o2 ! out] vessel be+ made ( glass or ord9>y /one w>e1 :ile ! inn] "o is made ( unglaz$ porcela91 & is !re=e por\s4 ,! out] vessel is fill$ ) dilute sulphuric acid1 & a plate ( amalgamat$ z9c--t is to say1 ( metallic z9c hav+ its out] surface bright5$ ) m]cury1--is imm]s$ 9 ?is acid4 ,aga91 9 ! inn] or por\s vessel we h /rong nitric acid1 9 :i* a plate ( plat9um foil is imm]s$1 ?is be+ at ! same "t electrically connect$ ) ! z9c plate ( ! next out] vessel1 by means ( a clamp1 z 9 ! figure4 ,bo? metals mu/ be clean :]e !y are press$ toge!r1 t is to say1 ! true metallic surfaces ( bo? mu/ be 9 contact4 ,f9ally1 a wire is metallically connect$ ) ! plat9um ( ! left-h& cell1 & a simil> wire ) ! z9c ( ! "r-h& cell1 & ^! connect+ wires ought1 except at _! extremities1 to be cov]$ ov] ) gutta-p]*a or ?read4 ,! loose extremities ( ^! wires are call$ ! poles ( ! batt]y4 #ic4 ,let u n[ suppose t we h a batt]y conta9+ a good _m cells ( ?is description1 & let ! :ole arrangem5t be insulat$1 by be+ set ^u glass supports1 or o!rwise sep>at$ f ! e>?4 ,if n[ we te/1 by appropriate me?ods1 ! extremity ( ! wire connect$ ) ! left-h& plat9um plate1 x w be f\nd to be *>g$ ) positive electricity1 :ile ! extremity ( ! o!r wire w be f\nd *>g$ ) negative electricity4 #id4 ,9 ! next place1 if we connect ^! poles ( ! batt]y ) "o ano!r1 ! two electricities w ru% toge!r & unite1 or1 9 o!r words1 !re w be an electric curr5t2 b x w n be a mom5t>y b a cont9u\s "o1 & = "s "t1 provid$ ^! poles are kept toge!r1 a curr5t ( electricity w pass ?r\gh ! wires1 & inde$ ?r\gh ! :ole arrangem5t1 includ+ ! cells4 ,! direction ( ! curr5t w be su* t positive electricity may be suppos$ to pass f ! z9c to ! plat9um1 ?r\gh ! liquid2 & back aga9 ?r\gh ! wire1 f ! plat9um at ! left h&1 to ! z9c at ! "r2 9 fact1 to g 9 ! direction indicat$ by ! arr[-head4 #ie4 ,?us we h two ?+s4 ,9 ! fir/ place1 be=e ! two t]m9als1 or poles1 h be5 br\ght toge!r1 we h !m *>g$ ) opposite electricities2 &1 secondly1 :5 once !y h be5 br\ght toge!r1 we h ! production ( a cont9u\s curr5t ( electricity4 ,n[1 ?is curr5t is an en]getic ag5t1 9 pro( ( :i* we %all proce$ to consid] ! v>i\s prop]ties :i* x has1--! v>i\s ?+s :i* x c d4 ,its ,magnetic ,effects4 #if4 ,9 ! fir/ place1 x c deflect ! magnetic ne$le4 ,= in/ance1 let a compass ne$le be swung freely1 & let a curr5t ( electricity circulate along a wire plac$ ne> ?is ne$le1 & 9 ! direction ( its l5g?1 !n ! direction 9 :i* ! ne$le po9ts w be imm$iately alt]$4 ,?is direction w n[ dep5d ^u t ( ! curr5t1 convey$ by ! wire1 & ! ne$le w endeav\r to place itself at "r angles to ?is wire4 ,9 ord] to rememb] ! connection betwe5 ! direction ( ! curr5t & t ( ! magnet1 imag9e y\r body to =m "p ( ! positive curr5t1 :i* may be suppos$ to ent] 9 at y\r head1 & g out at y\r feet2 also imag9e t y\r face is turn$ t[>ds ! magnet4 ,9 ?is case1 ! pole ( ! magnet1 :i* po9ts to ! nor?1 w always be deflect$ by ! curr5t t[>ds y\r "r h&4 ,! /r5g? ( a curr5t may be measur$ by ! am\nt ( ! deflection x produces ^u a magnetic ne$le1 & ! in/rum5t by :i* ?is measurem5t is made is call$ a galvanomet]4 #ig4 ,9 ! next place1 ! curr5t is able1 n m]ely to deflect a magnet1 b also to r5d] s(t iron magnetic4 ,let u take1 = in/ance1 ! wire connect$ ) ! "o pole ( ! batt]y1 & cov] x ) ?read1 9 ord] to insulate x1 & let u wrap ?is wire r\nd a cyl9d] ( s(t iron1 z 9 ,fig4 #i4 ,if we n[ make a communication betwe5 ! o!r extremity ( ! wire1 & ! o!r pole ( ! batt]y1 s z to make ! curr5t pass1 x w be f\nd t our cyl9d] ( s(t iron has become a p[]ful magnet1 & t if an iron keep] be atta*$ to x z 9 ! figure1 ! keep] w be able to su/a9 a v great weight4 ,illu/ration3 ,fig4 #i4 ,its ,heat+ ,effect4 #ih4 ,! electric curr5t has likewise ! prop]ty ( heat+ a wire ?r\gh :i* x passes4 ,to prove ?is1 let u connect ! two poles ( a batt]y by means ( a f9e plat9um wire1 :5 x w be f\nd t ! wire w1 9 a few seconds1 become heat$ to r$ness4 ,9 po9t ( fact1 ! curr5t w heat a ?ick wire1 b n s mu* z a ?9 "o1 = we may suppose x to ru% ) great viol5ce ?r\gh ! limit$ section ( ! ?9 wire1 produc+ 9 its passage great heat4 ,its ,*emical ,effect4 #ii4 ,besides its magnetic & heat+ effects1 ! curr5t has also ! p[] ( decompos+ comp\nd sub/ances1 "u c]ta9 conditions4 ,suppose1 = in/ance1 t ! poles ( a batt]y1 in/ead ( be+ br\ght toge!r1 are plung$ into a vessel ( wat]1 decomposition w at once beg91 & small bubbles ( oxyg5 w rise f ! positive pole1 :ile small bubbles ( hydrog5 w make _! appe>ance at ! negative4 ,if ! two gases are collect$ toge!r 9 a vessel1 !y may be explod$1 & if collect$ sep>ately1 x may be prov$ by ! ord9>y te/s1 t ! "o is oxyg5 & ! o!r hydrog54 ,attraction & ,repulsion ( ,curr5ts4 #ajj4 ,we h n[ describ$ v %ortly ! magnetic1 ! heat+1 & ! *emical effects ( curr5ts2 x rema9s = u to describe ! effects ( curr5ts ^u "o ano!r4 ,9 ! fir/ place1 suppose t we h two wires :i* are p>allel to "o ano!r1 & c>ry curr5ts go+ 9 ! same direction2 & let u fur!r suppose t ^! wires are capable ( mov+1 !n x is f\nd t !y w attract "o ano!r4 ,if1 h[ev]1 ! wires1 al?\gh p>allel1 convey curr5ts go+ 9 opposite directions1 !y w !n repel "o ano!r4 ,a good way ( %[+ ?is exp]im5tally is to cause two circul> curr5ts to float on wat]4 ,if ^! curr5ts bo? g ei!r 9 ! same direction z ! h&s ( a wat*1 or 9 ! opposite direction1 !n ! two w attract "o ano!r2 b if ! "o goes 9 ! "o direction1 & ! o!r 9 ! o!r1 !y w !n repel "o ano!r4 ,attraction & ,repulsion ( ,magnets4 #aja4 ,ampre1 :o discov]$ ?is prop]ty ( curr5ts1 has likewise %[n u t 9 v _m respects a magnet may be lik5$ to a collection ( circul> curr5ts all p>allel to "o ano!r1 _! direction be+ su* t1 if y look t[>ds ! nor? pole ( a freely susp5d$ cyl9drical magnet fac+ x1 ! positive curr5t w desc5d on ! ea/ or left-h& side1 & asc5d on ! we/ or "r-h& side4 ,if we adopt ?is me?od ( view+ magnets1 we c easily acc\nt = ! attraction betwe5 ! unlike & ! repulsion betwe5 ! l poles ( a magnet1 = :5 unlike poles are plac$ ne> ea* o!r1 ! circul> curr5ts :i* face ea* o!r are !n all go+ 9 ! same direction1 & ! two w1 !re=e1 attract "o ano!r1 b if l poles are plac$ 9 ?is position1 ! curr5ts t face ea* o!r are go+ 9 opposite directions1 & ! poles w1 !re=e1 repel "o ano!r4 ,illu/ration3 ,fig4 #aj4 ,induction ( ,curr5ts4 #ajb4 ,be=e clos+ ?is %ort sket* ( electrical ph5om5a1 we mu/ allude to ! inductive effect ( curr5ts ^u ea* o!r4 ,let u suppose 7,fig4 #aj7 t we h two circul> coils ( wire1 cov]$ ) ?read1 & plac$ ne> ea* o!r4 ,let bo? ! extremities ( ! "r-h& coil be connect$ ) ! poles ( a batt]y1 s z to make a curr5t ( electricity circulate r\nd ! coil4 ,on ! o!r h&1 let ! left-h& coil be connect$ ) a galvanomet]1 ?us enabl+ u to detect ! smalle/ curr5t ( electricity :i* may pass ?r\gh ?is coil4 ,n[1 x is f\nd t :5 we fir/ connect ! "r-h& coil1 s z to pass ! batt]y curr5t ?r\gh x1 a mom5t>y curr5t w pass ?r\gh ! left-h& coil1 & w deflect ! ne$le ( ! galvanomet]1 b ?is curr5t w g 9 an opposite direction to t :i* circulates r\nd ! "r-h& coil4 #ajc4 ,aga91 z long z ! curr5t cont9ues to fl[ ?r\gh ! "r-h& coil !re w be no curr5t ?r\gh ! o!r1 b at ! mom5t ( break+ ! contact betwe5 ! "r-h& coil & ! batt]y !re w aga9 be a mom5t>y curr5t 9 ! left-h& coil1 b ?is "t 9 ! same direction z t ( ! "r-h& coil1 in/ead ( be+1 z be=e1 9 ! opposite direction4 ,9 o!r words1 :5 contact is made 9 ! "r-h& coil1 !re is a mom5t>y curr5t 9 ! left-h& coil1 b 9 an opposite direction to t 9 ! "r1 :ile1 :5 contact is brok5 9 ! "r-h& coil1 !re is a mom5t>y curr5t 9 ! left-h& coil 9 ! same direction z t 9 ! "r4 #ajd4 ,9 ord] to exemplify ?is induction ( curr5ts1 x is n ev5 necess>y to make & break ! curr5t 9 ! "r-h& coil1 = we may keep x con/antly go+ & arrange s z to make ! "r-h& coil 7always reta9+ its connection ) ! batt]y7 alt]nately approa* & rec$e f ! o!r2 :5 x approa*es ! o!r1 ! effect produc$ w be ! same z :5 ! contact 0 made 9 ! above exp]im5t--t is to say1 we %all h an induc$ curr5t 9 an opposite direction to t ( ! prim>y1 :ile1 :5 x rec$es f ! o!r1 we %all h a curr5t 9 ! same direction z t ( ! prim>y4 #aje4 ,?us we see t :e!r we keep bo? coils /ation>y1 & sudd5ly produce a curr5t 9 ! "r-h& coil1 or :e!r1 keep+ ?is curr5t con/antly go+1 we sudd5ly br+ x ne> ! o!r coil1 ! inductive effect w be precisely ! same1 = 9 bo? cases ! left-h& coil is sudd5ly br\ght into ! pres5ce ( a curr5t4 ,& aga91 x is ! same1 :e!r we sudd5ly break ! "r-h& curr5t1 or sudd5ly remove x f ! left-h& coil1 = 9 bo? cases ?is coil is virtually remov$ f ! pres5ce ( a curr5t4 ,li/ ( ,en]gies4 #ajf4 ,we are n[ 9 a position to enum]ate ! v>i\s k9ds ( en]gy :i* occur 9 nature2 b1 be=e do+ s1 we mu/ w>n our read]s t ?is enum]ation has no?+ absolute or complete ab\t x1 repres5t+1 z x does1 n s mu* ! pres5t /ate ( our k z ( our want ( k1 or r pr(\nd ignorance1 ( ! ultimate con/itution ( matt]4 ,x is1 9 tru?1 only a conv5i5t classification1 & no?+ m4 #ajg4 ,to beg91 !n1 ) visible en]gy4 ,we h fir/ ( all-- ,en]gy ( ,visible ,motion4 7,a47 ,visible en]gy ( actual motion--9 ! planets1 9 meteors1 9 ! cannon ball1 9 ! /orm1 9 ! runn+ /ream1 & 9 o!r in/ances ( bodies 9 actual visible motion1 too num]\s to be m5tion$4 ,visible ,en]gy ( ,position4 7,b47 ,we h also visible en]gy ( position--9 a /one on ! top ( a cliff1 9 a head ( wat]1 9 a ra9 cl\d1 9 a cross-b[ b5t1 9 a clock or wat* w\nd up1 & 9 v>i\s o!r in/ances4 #ajh4 ,!n we h1 besides1 sev]al cases 9 :i* !re is an alt]nation betwe5 7,a7 & 7,b74 ,a p5dulum1 = in/ance1 :5 at its l[e/ po9t1 has only ! en]gy 7,a71 or t ( actual motion1 9 virtue ( :i* x asc5ds a c]ta9 di/ance aga9/ ! =ce ( gravity4 ,:51 h[ev]1 x has complet$ its asc5t1 its en]gy is !n ( ! v>iety 7,b71 be+ due to position1 & n to actual motion2 & s on x cont9ues to oscillate1 alt]nately *ang+ ! nature ( its en]gy f 7,a7 to 7,b71 & f 7,b7 back aga9 to 7,a74 #aji4 ,a vibrat+ body is ano!r in/ance ( ?is alt]nation4 ,ea* p>ticle ( su* a body may be comp>$ to an exce$+ly small p5dulum oscillat+ backw>ds & =w>ds1 only v mu* quick] ?an an ord9>y p5dulum2 & j z ! ord9>y p5dulum 9 pass+ its po9t ( re/ has its en]gy all ( "o k9d1 :ile 9 pass+ its upp] po9t x has x all ( ano!r1 s :5 a vibrat+ p>ticle is pass+ its po9t ( re/1 its en]gy is all ( ! v>iety 7,a71 & :5 x has rea*$ its extreme displacem5t1 x is all ( ! v>iety 7,b74 ,heat ,motion4 #aaj4 7,c47 ,com+ n[ to molecul> or invisible en]gy1 we h1 9 ! fir/ place1 t motion ( ! molecules ( bodies :i* we t]m heat4 ,a bett] t]m w\ld be absorb$ heat1 to di/+ui% x f radiant heat1 :i* is a v diff]5t ?+4 ,t peculi> motion :i* is imp>t$ by heat :5 absorb$ into a body is1 !re=e1 "o v>iety ( molecul> en]gy4 ,molecul> ,sep>ation4 7,d47 ,analog\s to ?is is t effect ( heat :i* repres5ts position r ?an actual motion4 ,= "p ( ! en]gy ( absorb$ heat is sp5t 9 pull+ asund] ! molecules ( ! body "u ! attractive =ce :i* b9ds !m toge!r 7,art4 #gc71 & ?us a /ore ( en]gy ( position is laid up1 :i* disappe>s aga9 aft] ! body is cool$4 ,atomic or ,*emical ,sep>ation4 #aaa4 7,e47 ,! two previ\s v>ieties ( en]gy may be view$ z associat$ ) molecules r ?an ) atoms1 & ) ! =ce ( cohesion r ?an ) t ( *emical aff9ity4 ,proce$+ n[ to atomic =ce1 we h a species ( en]gy ( position due to ! sep>ation ( diff]5t atoms "u ! /rong *emical attraction !y h = "o ano!r4 ,?us1 :5 we possess coal or c>bon & also oxyg5 9 a /ate ( sep>ation f "o ano!r1 we are 9 possession ( a s\rce ( en]gy :i* may be call$ t ( *emical sep>ation4 ,electrical ,sep>ation4 #aab 7,f47 ,! attraction :i* het]og5e\s atoms possess = "o ano!r1 sometimes1 h[ev]1 gives rise to a species ( en]gy :i* manife/s itself 9 a v peculi> =m1 & appe>s z electrical sep>ation1 :i* is ?us ano!r =m ( en]gy ( position4 ,electricity 9 ,motion4 #aac 7,g47 ,b we h ano!r species ( en]gy connect$ ) electricity1 = we h t due to electricity 9 motion1 or 9 o!r words1 an electric curr5t :i* probably repres5ts "s =m ( actual motion4 ,radiant ,en]gy4 #aad 7,h47 ,x is well kn[n t !re is no ord9>y matt]1 or at lea/ h>dly any1 betwe5 ! sun & ! e>?1 & yet we h a k9d ( en]gy :i* we may call radiant en]gy1 :i* proce$s to u f ! sun1 & proce$s also ) a def9ite1 ?\gh v great velocity1 tak+ ab\t eight m9utes to p]=m its j\rney4 ,n[1 ?is radiant en]gy is kn[n to consi/ ( ! vibrations ( an ela/ic m$ium p]vad+ all space1 :i* is call$ e!r1 or ! e!real m$ium4 ,inasmu*1 !re=e1 z x consi/s ( vibrations1 x p>takes ( ! "* ( p5dulum motion1 t is to say1 ! en]gy ( any e!real p>ticle is alt]nately t ( position & t ( actual motion4 ,law ( ,cons]vation4 #aae4 ,hav+ ?us endeav\r$1 provisionally at lea/1 to catalogue our v>i\s en]gies1 we are 9 a position to /ate m def9itely :at is meant by ! cons]vation ( en]gy4 ,= ?is purpose1 let u take ! univ]se z a :ole1 or1 if ?is be too l>ge1 let u conceive1 if possible1 a small portion ( x to be isolat$ f ! re/1 z f> z =ce or en]gy is conc]n$1 =m+ a sort ( microcosm1 to :i* we may conv5i5tly direct our att5tion4 ,?is portion1 !n1 nei!r p>ts ) any ( its en]gy to ! univ]se beyond1 nor receives any f x4 ,su* an isolation is1 ( c\rse1 unnatural & impossible1 b x is conceivable1 & w1 at lea/1 t5d to conc5trate our ?\ghts4 ,n[1 :e!r we reg>d ! great univ]se1 or ?is small microcosm1 ! pr9ciple ( ! cons]vation ( en]gy ass]ts t ! sum ( all ! v>i\s en]gies is a con/ant quantity1 t is to say1 adopt+ ! language ( ,algebra-- 7,a7 7,b7 7,c7 7,d7 7,e7 7,f7 7,g7 7,h7 a con/ant quantity4 #aaf4 ,?is does n mean1 ( c\rse1 t 7,a7 is con/ant 9 itself1 or any o!r ( ! left-h& memb]s ( ?is equation1 =1 9 tru?1 !y are always *ang+ ab\t into ea* o!r--n[1 "s visible en]gy be+ *ang$ into heat or electricity2 &1 anon1 "s heat or electricity be+ *ang$ back aga9 into visible en]gy--b x only means t ! sum ( all ! en]gies tak5 toge!r is con/ant4 ,we h1 9 fact1 9 ! left h&1 eight v>iable quantities1 & we only ass]t t _! sum is con/ant1 n by any means t !y are con/ant !mselves4 #aag4 ,n[1 :at evid5ce h we = ?is ass]tion8 ,x may be repli$ t we h ! /ronge/ possible evid5ce :i* ! nature ( ! case admits (4 ,! ass]tion is1 9 tru?1 a peculi> "o--peculi> 9 its magnitude1 9 its univ]sality1 9 ! subtle nature ( ! ag5ts ) :i* x deals4 ,if true1 its tru? c]ta9ly _c be prov$ aft] ! mann] 9 :i* we prove a proposition 9 ,euclid4 ,nor does x ev5 admit ( a pro( s rigid z t ( ! some:at analog\s pr9ciple ( ! cons]vation ( matt]1 = 9 *emi/ry we may conf9e ! products ( our *emical comb9ation s completely z to prove1 beyond a d\bt1 t no heavy matt] passes out ( exi/5ce t--:5 coal1 = in/ance1 burns 9 oxyg5 gas--:at we h is m]ely a *ange ( condition4 ,b we _c s easily prove t no en]gy is de/roy$ 9 ?is comb9ation1 & t ! only result is a *ange f ! en]gy ( *emical sep>ation into t ( absorb$ heat1 = dur+ ! process x is impossible to isolate ! en]gy--d :at we may1 "s ( x w escape into ! room 9 :i* we p]=m ! exp]im5t2 "s ( x w1 no d\bt1 escape ?r\gh ! w9d[1 :ile a little w leave ! e>? altoge!r1 & g out into space4 ,all t we c d 9 su* a case is to e/imate1 z completely z possible1 h[ mu* en]gy has gone away1 s9ce we _c possibly prev5t its go+4 ,b ?is is an op]ation involv+ great acqua9tance ) ! laws ( en]gy1 & v great exactness ( obs]vation3 9 f9e1 our read]s w at once p]ceive t x is mu* m difficult to prove ! tru? ( ! cons]vation ( en]gy ?an t ( ! cons]vation ( matt]4 #aah4 ,b if x be difficult to prove our pr9ciple 9 ! mo/ rigor\s mann]1 we are yet able to give ! /ronge/ possible indirect evid5ce ( its tru?4 ,our read]s are no d\bt famili> ) a me?od :i* ,euclid frequ5tly adopts 9 prov+ 8 propositions4 ,/>t+ ) ! supposition t !y are n true1 & reason+ ^u ?is hypo!sis1 he comes to an absurd conclusion--h5ce he concludes t !y are true4 ,n[1 we may adopt a me?od some:at simil> ) reg>d to our pr9ciple1 only in/ead ( suppos+ x untrue1 let u suppose x true4 ,x may !n be %[n t1 if x be true1 "u c]ta9 te/ conditions we ought to obta9 c]ta9 results--= in/ance1 if we increase ! pressure1 we ought to l[] ! freez+ po9t ( wat]4 ,well1 we make ! exp]im5t1 & f9d t1 9 po9t ( fact1 ! freez+ po9t ( wat] is l[]$ by increas+ ! pressure1 & we h ?us d]iv$ an argum5t 9 fav\r ( ! cons]vation ( en]gy4 #aai4 ,or aga91 if ! laws ( en]gy are true1 x may be %[n t1 :5ev] a sub/ance contracts :5 heat$1 x w become cold] in/ead ( hott] by compression4 ,n[1 we "k t ice-cold wat]1 or wat] j a little above its freez+ po9t1 contracts in/ead ( exp&+ up to #d ,c42 & ,sir ,william ,?omson has f\nd1 by exp]im5t1 t wat] at ?is temp]ature is cool$ in/ead ( heat$ by sudd5 compression4 ,india-rubb] is ano!r in/ance ( ?is relation betwe5 ^! two prop]ties1 = if we /ret* a /r+ ( india-rubb] x gets hott] in/ead ( cold]1 t is to say1 its temp]ature rises by ext5sion1 & gets l[] by contraction2 & aga91 if we heat ! /r+1 we f9d t x contracts 9 l5g? in/ead ( exp&+ l o!r sub/ances z its temp]ature increases4 #abj4 ,numb]less in/ances occur 9 :i* we are enabl$ to pr$ict :at w happ5 by assum+ ! tru? ( ! laws ( en]gy2 9 o!r words1 ^! laws are prov$ to be true 9 all cases :]e we c put !m to ! te/ ( rigor\s exp]im5t1 & probably we c h no bett] pro( ?an ?is ( ! tru? ( su* a pr9ciple4 ,we %all !re=e proce$ ^u ! assumption t ! cons]vation ( en]gy holds true 9 all cases1 & give our read]s a li/ ( ! v>i\s transmutations ( ?is subtle ag5t z x goes backw>ds & =w>ds f "o abode to ano!r1 mak+1 mean:ile1 sundry rem>ks t may t5d1 we tru/1 to conv9ce our read]s ( ! tru? ( our assumption4 ,,*apt] ,,iv4 ,,transmutations ,,( ,,en]gy4 ,en]gy ( ,visible ,motion4 #aba4 ,let u beg9 our li/ ( transmutations ) ! en]gy ( visible motion4 ,?is is *ang$ into en]gy ( position :5 a /one is project$ upw>ds above ! e>?1 or1 to take a case precisely simil>1 :5 a planet or a comet goes f p]ihelion1 or its position ne>e/ ! sun1 to aphelion1 or its position fur!/ f ! sun4 ,we ?us see :y a heav5ly body %\ld move fa/e/ at p]ihelion1 & sl[e/ at aphelion4 ,if1 h[ev]1 a planet 7 to move r\nd ! sun 9 an orbit exactly circul>1 its velocity w\ld be ! same at all ! v>i\s po9ts ( ?is orbit1 because !re w\ld be no *ange 9 its di/ance f ! c5tre ( attraction1 & !re=e no transmutation ( en]gy4 #abb4 ,we h already 7,arts4 #ajh1 #aji7 said t ! en]gy 9 an oscillat+ or vibrat+ body is alt]nately t ( actual motion1 & t ( position4 ,9 ?is respect1 !re=e1 a p5dulum is simil> to a comet or heav5ly body ) an elliptical orbit4 ,nev]!less ! *ange ( en]gy is g5]ally m complete 9 a p5dulum or vibrat+ body ?an x is 9 a heav5ly body2 = 9 a p5dulum1 :5 at its l[e/ po9t1 ! en]gy is entirely t ( actual motion1 :ile at its upp] po9t x is entirely t ( position4 ,n[1 9 a heav5ly body we h only a less5+1 b n an entire de/ruction1 ( ! velocity1 z ! body passes f p]ihelion to aphelion--t is to say1 we h only a p>tial conv]sion ( ! "o k9d ( en]gy into ! o!r4 #abc4 ,let u next consid] ! *ange ( actual visible en]gy into absorb$ heat4 ,?is takes place 9 all cases ( friction1 p]cussion1 & resi/ance4 ,9 friction1 = in/ance1 we h ! conv]sion ( "w or en]gy into heat1 :i* is "h produc$ ?r\gh ! rubb+ ( surfaces aga9/ ea* o!r2 & ,davy has %[n t two pieces ( ice1 bo? cold] ?an ! freez+ po9t1 may be melt$ by friction4 ,9 p]cussion1 aga91 we h ! en]gy ( ! bl[ conv]t$ into heat2 :ile1 9 ! case ( a meteor or cannon ball pass+ ?r\gh ! air ) great velocity1 we h ! loss ( en]gy ( ! meteor or cannon ball ?r\gh its contact ) ! air1 & at ! same "t ! production ( heat on acc\nt ( ?is resi/ance4 ,! resi/ance ne$ n be atmosph]ic1 = we may set ! cannon ball to pi]ce ?r\gh wood5 planks or ?r\gh s&1 & !re w equally be a production ( heat on acc\nt ( ! resi/ance (f]$ by ! wood5 planks or by ! s& to ! motion ( ! ball4 ,we may ev5 g5]alize /ill fur!r1 & ass]t t :5ev] ! visible mom5tum ( a body is transf]r$ to a l>g] mass1 !re is at ! same "t ! conv]sion ( visible en]gy into heat4 #abd4 ,a little explanation w be requir$ to make ?is po9t cle>4 ,! ?ird law ( motion tells u t action & reaction are equal & opposite1 s t :5 two bodies come into collision ! =ces at "w g5]ate equal & opposite quantities ( mom5tum4 ,we %all be/ see ! mean+ ( ?is law by a num]ical example1 be>+ 9 m9d t mom5tum means ! product ( mass into velocity4 ,= in/ance1 let u suppose t an inela/ic body ( mass #aj & velocity #bj /rikes directly ano!r inela/ic body ( mass #ae & velocity #ae1 ! direction ( bo? motions be+ ! same4 ,n[1 x is well kn[n t ! unit$ mass w1 aft] impact1 be mov+ ) ! velocity #ag4 ,:at1 !n1 has be5 ! influ5ce ( ! =ces develop$ by collision8 ,! body ( great] velocity _h be=e impact a mom5tum #aj #bj #bjj1 :ile its mom5tum aft] impact is only #aj #ag #agj2 x has !re=e suff]$ a loss ( #cj units z reg>ds mom5tum1 or we may consid] t a mom5tum ( #cj units has be5 impress$ ^u x 9 an opposite direction to its previ\s motion4 ,on ! o!r h&1 ! body ( small] velocity _h be=e impact a mom5tum #ae #ae #bbe1 :ile aft] impact x has #ae #ag #bee units1 s t its mom5tum has be5 increas$ by #cj units 9 its previ\s direction4 ,! =ce ( impact has !re=e g5]at$ #cj units ( mom5tum 9 two opposite directions1 s t1 tak+ acc\nt ( direction1 ! mom5tum ( ! sy/em is ! same be=e & aft] impact2 = be=e impact we _h a mom5tum ( #aj #bj #ae #ae #dbe1 :ile aft] x we h ! unit$ mass #be mov+ ) ! velocity #ag1 giv+ ! mom5tum #dbe z be=e4 #abe4 ,b :ile ! mom5tum is ! same be=e & aft] impact1 ! visible en]gy ( ! mov+ mass is und\bt$ly less aft] impact ?an be=e x4 ,to see ?is we h only to turn to ! expression ( ,art4 #bh1 f :i* we f9d t ! en]gy be=e impact 0 z foll[s3--,en]gy 9 kilogrammetres 7m v7_/7#ai #f7 7#aj #bj #ae #ae7_/aif #cgf ne>ly2 :ile t aft] impact 7#be #ag7_/aif #cfh ne>ly4 #abf4 ,! loss ( en]gy w be /ill m manife/ if we suppose an inela/ic body 9 motion to /rike aga9/ a simil> body at re/4 ,?us if we h a body ( mass #bj & velocity #bj /rik+ aga9/ "o ( equal mass1 b at re/1 ! velocity ( ! d\ble mass aft] impact w obvi\sly be only #aj2 b1 z reg>ds en]gy1 t be=e impact w be 7#bj #bj7_/aif #f :ile t aft] impact w be 7#dj #aj7_/aif #f or only half ! =m]4 #abg4 ,?us !re is 9 all su* cases an app>5t loss ( visible en]gy1 :ile at ! same "t !re is ! production ( heat on acc\nt ( ! bl[ :i* takes place4 ,if1 h[ev]1 ! sub/ances t come toge!r be p]fectly ela/ic 7:i* no sub/ance is71 ! visible en]gy aft] impact w be ! same z t be=e1 & 9 ?is case !re w be no conv]sion into heat4 ,?is1 h[ev]1 is an extreme supposition1 & inasmu* z no sub/ance is p]fectly ela/ic1 we h 9 all cases ( collision a great] or less conv]sion ( visible motion into heat4 #abh4 ,we h spok5 7,art4 #abb7 ab\t ! *ange ( en]gy 9 an oscillat+ or vibrat+ body1 z if x 7 entirely "o ( actual en]gy into en]gy ( position1 & ! rev]se4 ,b ev5 "h1 9 ea* oscillation or vibration1 !re is a great] or less conv]sion ( visible en]gy into heat4 ,let u1 = in/ance1 take a p5dulum1 &1 9 ord] to make ! circum/ances z fav\rable z possible1 let x sw+ on a knife edge1 & 9 vacuo2 9 ?is case !re w be a slight b con/ant friction ( ! knife edge aga9/ ! plane on :i* x re/s1 & ?\gh ! p5dulum may cont9ue to sw+ = h\rs1 yet x w ultimately come to re/4 ,&1 aga91 x is impossible to make a vacuum s p]fect t !re is absolutely no air surr\nd+ ! p5dulum1 s t "p ( ! motion ( ! p5dulum w always be c>ri$ (f by ! residual air ( ! vacuum 9 :i* x sw+s4 #abi4 ,n[1 some?+ simil> happ5s 9 t vibratory motion :i* con/itutes s\nd4 ,?us1 :5 a bell is 9 vibration1 "p ( ! en]gy ( ! vibration is c>ri$ (f by ! surr\nd+ air1 & x is 9 virtue ( ?is t we he> ! s\nd ( ! bell2 b1 ev5 if !re 7 no air1 ! bell w\ld n g on vibrat+ = ev]4 ,= !re is 9 all bodies a great] or less am\nt ( int]nal viscosity1 a prop]ty :i* prev5ts p]fect fre$om ( vibration1 & :i* ultimately conv]ts vibrations into heat4 ,a vibrat+ bell is ?us v mu* 9 ! same position z an oscillat+ p5dulum1 = 9 bo? "p ( ! en]gy is giv5 (f to ! air1 & 9 bo? !re is unavoidable friction--9 ! "o tak+ ! %ape ( int]nal viscosity1 & 9 ! o!r t ( friction ( ! knife edge aga9/ ! plane on :i* x re/s4 #acj4 ,9 bo? ^! cases1 too1 t portion ( ! en]gy :i* goes into ! air takes ultimately ! %ape ( heat4 ,! oscillat+ p5dulum communicates a motion to ! air1 & ?is motion ultimately heats ! air4 ,! vibrat+ bell1 or musical in/rum5t1 9 l mann] communicates "p ( its en]gy to ! air4 ,?is communicat$ en]gy fir/ ( all moves ?r\gh ! air ) ! well-kn[n velocity ( s\nd1 b dur+ its progress x1 too1 no d\bt becomes p>tly conv]t$ into heat4 ,ultimately1 x is transmitt$ by ! air to o!r bodies1 & by means ( _! int]nal viscosity is soon] or lat] conv]t$ into heat4 ,?us we see t heat is ! =m ( en]gy1 into :i* all visible t]re/rial motion1 :e!r x be rectil9e>1 or oscillatory1 or vibratory1 is ultimately *ang$4 #aca4 ,9 ! case ( a body 9 visible rectil9e> motion on ! e>?'s surface1 ?is *ange takes place v soon--if ! motion be rotatory1 su* z t ( a heavy revolv+ top1 x may1 p]haps1 cont9ue long] be=e x is ultimately /opp$1 by means ( ! surr\nd+ air1 & by friction ( ! pivot2 if x be oscillatory1 z 9 ! p5dulum1 or vibratory1 z 9 a musical in/rum5t1 we h se5 t ! air & int]nal friction are at "w1 9 "o %ape or ano!r1 to c>ry x (f1 & w ultimately succe$ 9 conv]t+ x into heat4 #acb4 ,b1 x may be said1 :y consid] a body mov+ on ! e>?'s surface8 :y n consid] ! motion ( ! e>? itself8 ,w ?is also ultimately take ! %ape ( heat8 ,no d\bt x is m difficult to trace ! conv]sion 9 su* a case1 inasmu* z x is n proce$+ at a s5sible rate be=e our eyes4 ,9 o!r words1 ! v conditions t make ! e>? habitable1 & a fit abode = intellig5t be+s l ourselves1 are ^? :i* unfit u to p]ceive ?is conv]sion ( en]gy 9 ! case ( ! e>?4 ,yet we are n )\t indications t x is actually tak+ place4 ,= ! purpose ( exhibit+ ^!1 we may divide ! e>?'s motion into two--a motion ( rotation1 & "o ( revolution4 #acc4 ,n[1 ) reg>d to ! e>?'s rotation1 ! conv]sion ( ! visible en]gy ( ?is motion into heat is already well recogniz$4 ,to und]/& ?is we h only to /udy ! nature ( ! moon's action ^u ! fluid portions ( our globe4 ,9 ! foll[+ diagram 7,fig4 #aa7 we h an exagg]at$ repres5tation ( ?is1 by :i* we see t ! sph]ical e>? is conv]t$ into an elongat$ oval1 ( :i* "o extremity always po9ts to ! moon4 ,! solid body ( ! e>? itself revolves z usual1 b1 nev]!less1 ?is fluid protub]ance rema9s always po9t+ t[>ds ! moon1 z we see 9 ! figure1 & h5ce ! e>? rubs aga9/ ! protub]ance z x revolves4 ,! friction produc$ by ?is action t5ds evid5tly to less5 ! rotatory en]gy ( ! e>?--9 o!r words1 x acts l a break--& we h1 j z by a break-:eel1 ! conv]sion ( visible en]gy into heat4 ,?is 0 fir/ recogniz$ by ,may] & ,j4 ,?omson4 ,illu/ration3 ,fig4 #aa4 #acd4 ,b :ile !re c be no d\bt ab\t ! fact ( su* a conv]sion go+ on1 ! only "q is reg>d+ its rate ( progress1 & ! "t requir$ be=e x c cause a p]ceptible impression ^u ! rotative en]gy ( ! e>?4 ,n[1 x is believ$ by a/ronom]s t !y h detect$ evid5ce ( su* a *ange1 = our k ( ! motions ( ! sun & moon has become s exact1 t n only c we c>ry =w>d our calculations s z to pr$ict an eclipse1 b also c>ry !m backw>ds1 & ?us fix ! dates & ev5 ! v details ( ! anci5t hi/orical eclipses4 ,if1 h[ev]1 betwe5 ^? times & ! pres5t1 ! e>? has lo/ a little rotative en]gy on acc\nt ( ?is peculi> action ( ! moon1 !n x is evid5t t ! calculat$ circum/ances ( ! anci5t total eclipse w n q agree ) ^? actually record$2 & by a comp>ison ( ?is nature x is believ$ t we h detect$ a v slight fall+ (f 9 ! rotative en]gy ( our e>?4 ,if we c>ry out ! argum5t1 we %all be driv5 to ! conclusion t ! rotative en]gy ( our globe w1 on acc\nt ( ! moon's action1 always get less & less1 until ?+s are br\ght into su* a /ate t ! rotation comes to be p]=m$ 9 ! same "t z ! revolution ( ! moon1 s t !n ! same portion ( ! t]re/rial surface be+ always pres5t$ to ! moon1 x is evid5t t !re w be no ef=t made by ! solid sub/ance ( ! e>?1 to glide f "u ! fluid protub]ance1 & !re w 9 consequ5ce be no friction1 & no fur!r loss ( en]gy4 #ace4 ,if ! fate ( ! e>? be ultimately to turn ! same face always to ! moon1 we h abundant evid5ce t ?is v fate has long s9ce ov]tak5 ! moon h]self4 ,inde$1 ! mu* /rong] effect ( our e>? ^u ! moon has produc$ ?is result1 probably1 ev5 9 ^? remote p]iods :5 ! moon 0 *iefly fluid2 & x is a fact well kn[n1 n m]ely to a/ronom]s1 b to all ( u1 t ! moon n[adays turns always ! same face to ! e>?4#d ,no d\bt ?is fate has long s9ce ov]tak5 ! satellites ( ,jupit]1 ,saturn1 & ! o!r l>ge planets2 & !re are indep5d5t indications t1 at lea/ 9 ! case ( ,jupit]1 ! satellites turn always ! same face to _! prim>y4 #acf4 ,to come n[ to ! en]gy ( revolution ( ! e>?1 9 h] orbit r\nd ! sun1 we _c help believ+ t !re is a mat]ial m$ium ( "s k9d betwe5 ! sun & ! e>?2 inde$1 ! undulatory !ory ( light requires ?is belief4 ,b if we believe 9 su* a m$ium1 x is difficult to imag9e t its pres5ce w n ultimately dim9i% ! motion ( revolution ( ! e>? 9 h] orbit2 inde$1 !re is a /rong sci5tific probability1 if n an absolute c]ta9ty1 t su* w be ! case4 ,!re is ev5 "s reason to ?9k t ! en]gy ( a comet ( small p]iod1 call$ ,encke's comet1 is gradually be+ /opp$ f ?is cause2 9 f9e1 !re c be h>dly any d\bt t ! cause is really 9 op]ation1 & w ultimately affect ! motions ( ! planets & o!r heav5ly bodies1 ev5 al?\gh its rate ( action may be s sl[ t we are n able to detect x4 ,we may p]haps g5]alize by say+1 t :]ev] 9 ! univ]se !re is a diff]5tial motion1 t is to say1 a motion ( "o "p ( x t[>ds or f ano!r1 !n1 9 virtue ( ! subtle m$ium1 or cem5t1 t b9ds ! v>i\s p>ts ( ! univ]se toge!r1 ?is motion is n unatt5d$ by some?+ l friction1 9 virtue ( :i* ! diff]5tial motion w ultimately disappe>1 :ile ! loss ( en]gy caus$ by its disappe>ance w assume ! =m ( heat4 #acg4 ,!re are1 inde$1 obscure intimations t a conv]sion ( ?is k9d is n improbably tak+ place 9 ! sol> sy/em2 =1 9 ! sun himself1 we h ! matt] ne> ! equator1 by virtue ( ! rotation ( our lum9>y1 c>ri$ alt]nately t[>ds & f ! v>i\s planets4 ,n[1 x w\ld seem t ! sun-spots1 or atmosph]ic di/urbances ( ! sun1 affect p>ticul>ly 8 equatorial regions1 & h likewise a t5d5cy to atta9 _! maximum size 9 t position1 :i* is z f> away z possible f ! influ5tial planets1 su* z ,m]cury or ,v5us2#e s t if ,v5us1 = in/ance1 7 betwe5 ! e>? & ! sun1 !re w\ld be few sun-spots 9 ! middle ( ! sun's disc1 because t w\ld be ! "p ( ! sun ne>e/ ,v5us4 ,b if ! planets influ5ce sun-spots1 ! action is no d\bt reciprocal1 & we h mu* reason to believe t sun-spots influ5ce1 n only ! magnetism1 b also ! meteorology ( our e>?1 s t !re are mo/ displays ( ! ,aurora ,borealis1 z well z mo/ cyclones1 9 ^? ye>s :5 !re are mo/ sun-spots4#f ,is x n !n possible t1 9 ^! /range1 my/]i\s ph5om5a1 we see traces ( ! ma*9]y by means ( :i* ! diff]5tial motion ( ! sol> sy/em is gradually be+ *ang$ into heat8 #ach4 ,we h ?us se5 t visible en]gy ( actual motion is n unfrequ5tly *ang$ into visible en]gy ( position1 & t x is also v (t5 trans=m$ into absorb$ heat4 ,we h n[ to /ate t x may likewise be trans=m$ into electrical sep>ation4 ,?us1 :5 an ord9>y electrical ma*9e is 9 action1 consid]able lab\r is sp5t 9 turn+ ! h&le2 x is1 9 tru?1 h>d] to turn ?an if no electricity 7 be+ produc$--9 o!r words1 "p ( ! en]gy :i* is sp5t ^u ! ma*9e goes to ! production ( electrical sep>ation4 ,!re are o!r ways ( g5]at+ electricity besides ! frictional me?od4 ,if1 = in/ance1 we br+ an insulat$ conduct+ plate ne> ! prime conductor ( ! electrical ma*9e1 yet n ne> en\gh to cause a sp>k to pass1 & if we !n t\* ! insulat$ plate1 we %all f9d x1 aft] contact1 to be *>g$ ) an electricity ! opposite ( t 9 ! ma*9e2 we may !n remove x & make use ( ?is electricity4 ,x requires a little ?\ght to see :at lab\r we h sp5t 9 ?is process4 ,we mu/ be> 9 m9d t1 by t\*+ ! plate1 we h c>ri$ (f ! electricity ( ! same "n z t ( ! ma*9e1 s t1 aft] t\*+ ! insulat$ plate x is m /rongly attract$ to ! conductor ?an x 0 be=e4 ,:5 we beg9 to remove x1 !re=e1 x w co/ u an ef=t to d s1 & ! me*anical en]gy :i* we sp5d 9 remov+ x w acc\nt = ! en]gy ( electrical sep>ation :i* we !n obta94 #aci4 ,we may ?us make use ( a small nucleus ( electricity1 to assi/ u 9 procur+ an unlimit$ supply1 = 9 ! above process ! electricity ( ! prime conductor rema9s unalt]$1 & we may repeat ! op]ation z (t5 z we l1 & ga!r toge!r a v l>ge quantity ( electricity1 )\t f9ally alt]+ ! electricity ( ! prime conductor1 b n1 h[ev]1 )\t ! exp5diture ( an equival5t am\nt ( en]gy1 9 ! %ape ( actual "w4 #adj4 ,:ile1 z we h se51 !re is a t5d5cy 9 all motion to be *ang$ into heat1 !re is "o in/ance :]e x is1 9 ! fir/ place at lea/1 *ang$ into a curr5t ( electricity4 ,we allude to ! case :]e a conduct+ sub/ance moves 9 ! pres5ce ( an electric curr5t1 or ( a magnet4 ,9 ,art4 #ajd we f\nd t if "o coil connect$ ) a batt]y 7 quickly mov$ into ! pres5ce ( ano!r coil connect$ ) a galvanomet]1 an induc$ curr5t w\ld be g5]at$ 9 ! latt] coil1 & w\ld affect ! galvanomet]1 its direction be+ ! rev]se ( t pass+ 9 ! o!r4 ,n[1 an electric curr5t implies en]gy1 & we may !re=e conclude t "s o!r =m ( en]gy mu/ be sp5t1 or disappe>1 9 ord] to produce ! curr5t :i* is g5]at$ 9 ! coil atta*$ to ! galvanomet]4 ,aga91 we le>n f ,art4 #ajj t two curr5ts go+ 9 opposite directions repel "o ano!r4 ,! curr5t g5]at$ 9 ! coil atta*$ to ! galvanomet] or second>y curr5t w1 !re=e1 repel ! prim>y curr5t1 :i* is mov+ t[>ds x2 ?is repulsion w ei!r cause a /oppage ( motion1 or r5d] necess>y ! exp5diture ( en]gy1 9 ord] to keep up ! motion ( ?is mov+ coil4 ,we ?us f9d t two ph5om5a occur simultane\sly4 ,9 ! fir/ place1 !re is ! production ( en]gy 9 ! second>y coil1 9 ! %ape ( a curr5t opposite 9 direction to t ( ! prim>y coil2 9 ! next case1 ow+ to ! repulsion betwe5 ?is induc$ curr5t & ! prim>y curr5t1 !re is a /oppage or disappe>ance ( ! en]gy ( actual motion ( ! mov+ coil4 ,we h1 9 fact1 ! creation ( "o species ( en]gy1 & at ! same "t ! disappe>ance ( ano!r1 & ?us we see t ! law ( cons]vation is by no means brok54 #ada4 ,we see also ! necess>y connection betwe5 ! two electrical laws describ$ 9 ,arts4 #ajj & #ajd4 ,inde$1 _h ^! laws be5 o!r ?an :at !y are1 ! pr9ciple ( cons]vation ( en]gy w\ld h be5 brok54 ,= in/ance1 _h ! induc$ curr5t 9 ! case n[ m5tion$ be5 9 ! same direction z t ( ! prim>y1 ! two curr5ts w\ld h attract$ ea* o!r1 & ?us !re w\ld h be5 ! creation ( a second>y curr5t1 imply+ en]gy1 9 ! coil atta*$ to ! galvanomet]1 along ) an increase ( ! visible en]gy ( motion ( ! prim>y curr5t--t is to say1 in/ead ( ! creation ( "o k9d ( en]gy1 accompani$ ) ! disappe>ance ( ano!r1 we %\ld h _h ! simultane\s creation ( bo?2 & ?us ! law ( cons]vation ( en]gy w\ld h be5 brok54 ,we ?us see t ! pr9ciple ( cons]vation enables u to d$uce ! "o electrical law f ! o!r1 & ?is is "o ( ! _m in/ances :i* /r5g!n our belief 9 ! tru? ( ! great pr9ciple = :i* we are cont5d+4 #adb4 ,let u next consid] :at w take place if we cause ! prim>y curr5t to move f ! second>y coil in/ead ( t[>ds x4 ,9 ?is case we "k1 f ,art4 #ajd1 t ! induc$ curr5t w be 9 ! same direction z ! prim>y1 :ile we are told by ,art4 #ajj t ! two curr5ts w n[ attract ea* o!r4 ,! t5d5cy ( ?is attraction w be to /op ! motion ( ! prim>y curr5t f ! second>y "o1 or1 9 o!r words1 !re w be a disappe>ance ( ! en]gy ( visible motion1 :ile at ! same "t !re is ! production ( a curr5t4 ,9 bo? cases1 !re=e1 "o =m ( en]gy disappe>s :ile ano!r takes its place1 & 9 bo? !re w be a v p]ceptible resi/ance exp]i5c$ 9 mov+ ! prim>y coil1 :e!r t[>ds ! second>y or f x4 ,"w w1 9 fact1 h to be sp5t 9 bo? op]ations1 & ! outcome ( ?is "w or en]gy w be ! production ( a curr5t 9 ! fir/ place1 & ( heat 9 ! second2 = we le>n f ,art4 #ih t :5 a curr5t passes along a wire its en]gy is g5]ally sp5t 9 heat+ ! wire4 ,we h ?us two ph5om5a occurr+ toge!r4 ,9 ! fir/ place1 9 mov+ a curr5t ( electricity to & f a coil ( wire1 or any o!r conductor1 or 7:i* is ! same ?+1 s9ce action & reaction are equal & opposite7 9 mov+ a coil ( wire or any o!r conductor to & f a curr5t ( electricity1 a s5se ( resi/ance w be exp]i5c$1 & en]gy w h to be sp5t ^u ! process2 9 ! second place1 an electrical curr5t w be g5]at$ 9 ! conductor1 & ! conductor w be heat$ 9 consequ5ce4 #adc4 ,! result w be r5d]$ v prom95t if we cause a metallic top1 9 rapid rotation1 to sp9 ne> two iron poles1 :i*1 by means ( ! batt]y1 we c sudd5ly conv]t into ! poles ( a p[]ful electro-magnet4 ,:5 ?is *ange is made1 & ! poles become magnetic1 ! motion ( ! top is v spe$ily br\ght to re/1 j z if x _h to enc\nt] a species ( invisible friction4 ,?is curi\s result c easily be expla9$4 ,we h se5 f ,art4 #aja t a magnet resembles an assemblage ( electric curr5ts1 & 9 ! metallic top we h a conductor alt]nately approa*+ ^! curr5ts & rec$+ f !m2 & h5ce1 accord+ to :at has be5 said1 we %all h a s]ies ( second>y curr5ts produc$ 9 ! conduct+ top :i* w /op its motion1 & :i* w ultimately take ! %ape ( heat4 ,9 o!r words1 ! visible en]gy ( ! top w be *ang$ into heat j z truly z if x 7 /opp$ by ord9>y friction4 #add4 ,! electricity induc$ 9 a metallic conductor1 mov$ 9 ! pres5ce ( a p[]ful magnet1 has receiv$ ! "n ( ,magneto-,electricity2 & ,dr4 ,j\le has made use ( x z a conv5i5t means ( enabl+ him to det]m9e ! me*anical equival5t ( heat1 = x is into heat t ! en]gy ( motion ( ! conductor is ultimately trans=m$4 ,b1 besides all ?is1 ^! curr5ts =m1 p]haps1 ! v be/ means ( obta9+ electricity2 & rec5tly v p[]ful ma*9es h be5 con/ruct$ by ,wild & o!rs ) ?is view4 #ade4 ,^! ma*9es1 :5 l>ge1 are work$ by a /eam-eng9e1 & _! mode ( op]ation is z foll[s3--,! nucleus ( ! ma*9e is a sy/em ( p[]ful p]man5t /eel magnets1 & a conduct+ coil is made to revolve rapidly 9 pres5ce ( ^! magnets4 ,! curr5t produc$ by ?is mov+ coil is !n us$ 9 ord] to produce an extremely p[]ful electro-magnet1 & f9ally a coil is made to move ) great rapidity 9 pres5ce ( ?is p[]ful electro-magnet1 ?us caus+ induc$ curr5ts ( va/ /r5g?4 ,s p[]ful are ^! curr5ts1 t :5 us$ to produce ! electric light1 small pr9t may be read on a d>k night at ! di/ance ( two miles f ! sc5e ( op]ation6 ,x ?us appe>s t 9 ?is ma*9e a d\ble use is made ( magneto-electricity4 ,/>t+ ) a nucleus ( p]man5t magnetism1 ! magneto-electric curr5ts are us$1 9 ! fir/ in/ance1 to =m a p[]ful electro-magnet mu* /rong] ?an ! fir/1 & ?is p[]ful electro-magnet is aga9 made use ( 9 ! same way z ! fir/1 9 ord] to give1 by means ( magneto-electricity1 an induc$ curr5t ( v great /r5g?4 #adf4 ,!re is1 moreov]1 a v great lik5ess betwe5 a magneto-electric ma*9e l t ( ,wild's = g5]at+ electric curr5ts1 & ! "o :i* g5]ates /atical electricity by means ( ! me?od already describ$ ,art4 #aci4 ,9 bo? cases advantage is tak5 ( a nucleus1 = 9 ! magneto-electric ma*9e we h ! molecul> curr5ts ( a set ( p]man5t magnets1 :i* are made ! means ( g5]at+ enorm\s electric curr5ts )\t any p]man5t alt]ation to !mselves1 yet n )\t ! exp5diture ( "w4 ,aga91 9 an induction ma*9e = g5]at+ /atical electricity1 we h an electric nucleus1 su* z we h suppos$ to reside 9 ! prime conductor ( a ma*9e2 & advantage may be tak51 z we h se51 ( ?is nucleus 9 ord] to g5]ate a va/ quantity ( /atical electricity1 )\t any p]man5t alt]ation ( ! nucleus1 b n )\t ! exp5diture ( "w4 #adg4 ,we h n[ se5 "u :at conditions ! visible en]gy ( actual motion may be *ang$--#a/ly1 into en]gy ( position2 #bndly1 into ! two en]gies :i* embrace absorb$ heat2 #crdly1 into electrical sep>ation2 & f9ally into electricity 9 motion4 ,z f> z we "k1 visible en]gy _c directly be trans=m$ into *emical sep>ation1 or into radiant en]gy4 ,visible ,en]gy ( ,position4 #adh4 ,hav+ ?us exhau/$ ! transmutations ( ! en]gy ( visible motion1 we next turn to t ( position1 & f9d t x is transmut$ into motion1 b n imm$iately into any o!r =m ( en]gy2 we may1 !re=e1 dismiss ?is v>iety at once f our consid]ation4 ,absorb$ ,heat4 #adj4 ,com+ n[ to ^! two =ms ( en]gy :i* embrace absorb$ heat1 we f9d t ?is may be conv]t$ into 7,a7 or actual visible en]gy 9 ! case ( ! /eam-eng9e1 ! air-eng9e1 & all v>ieties ( heat eng9es4 ,9 ! /eam-eng9e1 = in/ance1 "p ( ! heat :i* passes ?r\gh x disappe>s z heat1 utt]ly & absolutely1 to reappe> z me*anical effect4 ,!re is1 h[ev]1 "o condition :i* mu/ be rigidly fulfill$1 :5ev] heat is *ang$ into me*anical effect--!re mu/ be a diff]5ce ( temp]ature1 & heat w only be *ang$ into "w1 :ile x passes f a body ( high temp]ature to "o ( l[4 ,c>not1 ! celebrat$ ,fr5* physici/1 has +5i\sly lik5$ ! me*anical p[] ( heat to t ( wat]2 = j z y c get no "w out ( heat unless !re be a fl[ ( heat f a high] temp]ature level to a l[]1 s nei!r c y get "w out ( wat] unless x be fall+ f a high] level to a l[]4 #aej4 ,if we reflect t heat is ess5tially di/ributive 9 its nature1 we %all soon p]ceive ! reason = ?is peculi> law2 =1 9 virtue ( its nature1 heat is always ru%+ f a body ( high temp]ature to "o ( l[1 & if left to itself x w\ld di/ribute itself equally among/ all bodies1 s t !y w\ld ultimately become ( ! same temp]ature4 ,n[1 if we are to coax "w out ( heat1 we mu/ hum\r its nature1 = x may be comp>$ to a pack ( s*oolboys1 :o are always ready to run ) suffici5t viol5ce out ( ! s*oolroom into ! op5 fields1 b :o h frequ5tly to be dragg$ back ) a v consid]able exp5diture ( en]gy4 ,s heat w n all[ itself to be conf9$1 b w resi/ any attempt to accumulate x into a limit$ space4 ,"w _c1 !re=e1 be ga9$ by su* an op]ation1 b mu/1 on ! contr>y1 be sp5t ^u ! process4 #aea4 ,let u n[ = a mom5t consid] ! case ( an enclosure 9 :i* ev]y?+ is ( ! same temp]ature4 ,"h we h a dull dead level ( heat1 out ( :i* x w be impossible to obta9 ! fa9te/ semblance ( "w4 ,! temp]ature may ev5 be high1 & !re may be imm5se /ores ( heat en]gy 9 ! enclosure1 b n a trace ( ?is is available 9 ! %ape ( "w4 ,tak+ up ,c>not's comp>ison1 ! wat] has already fall5 to ! same level1 & lies !re )\t any p[] ( do+ useful "w--dead1 9 a s5se1 z f> z visible en]gy is conc]n$4 #aeb4 ,we ?us p]ceive t1 fir/ly1 we c get "w out ( heat :5 x passes f a high] to a l[] temp]ature1 b t1 secondly1 we mu/ sp5d "w ^u x 9 ord] to make x pass f a l[] temp]ature to a high] "o2 & t1 ?irdly & f9ally1 no?+ 9 ! %ape ( "w c be got out ( heat :i* is all at ! same temp]ature level4 ,:at we h n[ said enables u to realize ! conditions "u :i* all heat eng9es "w4 ,! ess5tial po9t ab\t su* eng9es is1 n ! possession ( a cyl9d]1 or pi/on1 or fly :eels1 or valves1 b ! possession ( two *amb]s1 "o ( high & ! o!r ( l[ temp]ature1 :ile x p]=ms "w 9 ! process ( c>ry+ heat f ! *amb] ( high to t ( l[ temp]ature4 ,let u take1 = example1 ! l[-pressure eng9e4 ,"h we h ! boil] or *amb] ( high1 & ! cond5s] or *amb] ( l[1 temp]ature1 & ! eng9e works :ile heat is be+ c>ri$ f ! boil] to ! cond5s]--nev] :ile x is be+ c>ri$ f ! cond5s] to ! boil]4 ,9 l mann] 9 ! locomotive we h ! /eam g5]at$ at a high temp]ature & pressure1 & cool$ by injection into ! atmosph]e4 #aec4 ,b1 leav+ =mal eng9es1 let u take an ord9>y fire1 :i* plays 9 tru? ! "p ( an eng9e1 z f> z en]gy is conc]n$4 ,we h "h ! cold air /ream+ 9 ov] ! floor ( ! room1 & ru%+ into ! fire1 to be !re unit$ ) c>bon1 :ile ! r>efi$ product is c>ri$ up ! *imney4 ,dismiss+ f our ?\ghts at pres5t ! process ( combu/ion1 except z a means ( supply+ heat1 we see t !re is a cont9ual 9-draught ( cold air1 :i* is heat$ by ! fire1 & !n s5t to m+le ) ! air above4 ,heat is1 9 fact1 di/ribut$ by ?is means1 or c>ri$ f a body ( high temp]ature1 i4e4 ! fire1 to a body ( l[ temp]ature1 i4e4 ! out] air1 & 9 ?is process ( di/ribution me*anical effect is obta9$ 9 ! up-ru% ( air ?r\gh ! *imney ) consid]able velocity4 #aed4 ,our own e>? is ano!r in/ance ( su* an eng9e1 hav+ ! equatorial regions z its boil]1 & ! pol> regions z its cond5s]s2 =1 at ! equator1 ! air is heat$ by ! direct rays ( ! sun1 & we h !re an asc5d+ curr5t ( air1 up a *imney z x 71 ! place ( :i* is suppli$ by an 9-draught ( cold] air along ! gr\nd or floor ( ! _w1 f ! poles on bo? sides4 ,?us ! heat$ air makes its way f ! equator to ! poles 9 ! upp] regions ( ! atmosph]e1 :ile ! cold air makes its way f ! poles to ! equator along ! l[] regions4 ,v (t51 too1 aque\s vap\r z well z air is c>ri$ up by means ( ! sun's heat to ! upp] & cold] atmosph]ic regions1 & !re deposit$ 9 ! %ape ( ra91 or hail1 or sn[1 :i* ultimately f9ds its way back aga9 to ! e>?1 (t5 display+ 9 its passage imm5se me*anical en]gy4 ,inde$1 ! m>9] :o hoi/s 8 sail1 & ! mill] :o gr9ds 8 corn 7:e!r he use ! =ce ( ! w9d or t ( runn+ wat]71 are bo? dep5d5t ^u ?is great e>?-eng9e1 :i* is con/antly at "w produc+ me*anical effect1 b always 9 ! act ( c>ry+ heat f its hott] to its cold] regions4 #aee4 ,n[1 if x be ess5tial to an eng9e to h two *amb]s1 "o hot & "o cold1 x is equally important t !re %\ld be a consid]able temp]ature diff]5ce betwe5 ! two4 ,if ,nature insi/s ^u a diff]5ce be=e %e w give u "w1 we %all n be able to pacify h]1 or to meet h] requirem5ts by mak+ ?is diff]5ce z small z possible4 ,& h5ce1 ct]is p>ibus1 we %all obta9 a great] proportion ( "w out ( a c]ta9 am\nt ( heat pass+ ?r\gh our eng9e :5 ! temp]ature diff]5ce betwe5 its boil] & cond5s] is z great z possible4 ,9 a /eam-eng9e ?is diff]5ce _c be v great1 because if ! wat] ( ! boil] 7 at a v high temp]ature ! pressure ( its /eam w\ld become dang]\s2 b 9 an air-eng9e1 or eng9e t heats & cools air1 ! temp]ature diff]5ce may be mu* l>g]4 ,!re are1 h[ev]1 practical inconv5i5ces 9 eng9es = :i* ! temp]ature ( ! boil] is v high1 & x is possible t ^! may prove s =midable z to turn ! scale aga9/ su* eng9es1 al?\gh 9 !ory !y ought to be v economical4 #aef4 ,! pr9ciples n[ /at$ h be5 employ$ by ,pr(essor ,j4 ,?omson1 9 8 sugge/ion t ! application ( pressure w\ld be f\nd to l[] ! freez+ po9t ( wat]2 & ! tru? ( ?is sugge/ion 0 aft]w>ds prov$ by ,pr(essor ,sir ,w4 ,?omson4 ,! foll[+ 0 ! reason+ employ$ by ! =m]3-- ,suppose t we h a *amb] kept con/antly at ! temp]ature #j ,c41 or ! melt+ po9t ( ice1 & t we h a cyl9d]1 ( :i* ! sectional area is "o squ>e metre1 fill$ "o metre 9 height ) wat]1 t is to say1 conta9+ "o cubic metre ( wat]4 ,suppose1 next1 t a well-fitt+ pi/on is plac$ above ! surface ( ! wat] 9 ?is cyl9d]1 & t a consid]able weight is plac$ ^u ! pi/on4 ,let u n[ take ! cyl9d]1 wat] & all1 & c>ry x into ano!r room1 ( :i* ! temp]ature is j a trifle l[]4 ,9 c\rse ( "t ! wat] w freeze1 &1 z x exp&s 9 freez+1 x w pu% up ! pi/on & weight ab\t ?s ( a metre2 & we may suppose t ! pi/on is kept fa/5$ 9 ?is position by means ( a peg4 ,n[ c>ry back ! ma*9e into ! fir/ room1 & 9 ! c\rse ( "t ! ice w be melt$1 & we %all h wat] once m 9 ! cyl9d]1 b !re w n[ be a void space ( ?s ( a metre betwe5 ! pi/on & ! surface4 ,we h ?us acquir$ a c]ta9 am\nt ( en]gy ( position1 & we h only to pull out ! peg1 & all[ ! pi/on ) its weight to fall d[n ?r\gh ! vacant space1 9 ord] to utilize ?is en]gy1 aft] :i* ! arrangem5t is ready to />t afre%4 ,aga91 if ! weight be v great1 ! en]gy ?us ga9$ w be v great2 9 fact1 ! en]gy w v>y ) ! weight4 ,9 f9e1 ! arrangem5t n[ describ$ is a v]itable heat eng9e1 ( :i* ! *amb] at #j ,c4 corresponds to ! boil]1 & ! o!r *amb] a trifle l[] 9 temp]ature to ! cond5s]1 :ile ! am\nt ( "w we get out ( ! eng9e--or1 9 o!r words1 its effici5cy--w dep5d ^u ! weight :i* is rais$ ?r\gh ! space ( ?s ( a metre1 s t1 by increas+ ?is weight )\t limit1 we may increase ! effici5cy ( our eng9e )\t limit4 ,x w\ld ?us at fir/ sight appe> t by ?is device ( hav+ two *amb]s1 "o at #j ,c41 & ! o!r a trifle l[]1 we c get any am\nt ( "w out ( our wat] eng9e2 & t1 consequ5tly1 we h manag$ to ov]come ,nature4 ,b "h ,?omson's law come into op]ation1 %[+ t we _c ov]come ,nature by any su* device1 b t if we h a l>ge weight ^u our pi/on1 we mu/ h a proportionally l>ge diff]5ce ( temp]ature betwe5 our two *amb]s--t is to say1 ! freez+ po9t ( wat]1 "u great pressure1 w be l[] 9 temp]ature ?an its freez+ po9t1 if ! pressure ^u x be only small4 ,be=e leav+ ?is subject we mu/ call ^u our read]s to realize :at takes place 9 all heat eng9es4 ,x is n m]ely t heat produces me*anical effect1 b t a giv5 quantity ( heat absolutely passes out ( exi/5ce z heat 9 produc+ its equival5t ( "w4 ,if1 !re=e1 we c\ld measure ! m]e heat produc$ 9 an eng9e by ! burn+ ( a ton ( coals1 we %\ld f9d x to be less :5 ! eng9e 0 do+ "w ?an :5 x 0 at re/4 ,9 l mann]1 :5 a gas exp&s sudd5ly its temp]ature falls1 because a c]ta9 am\nt ( its heat passes out ( exi/5ce 9 ! act ( produc+ me*anical effect4 #aeg4 ,we h ?us endeav\r$ to %[ "u :at conditions absorb$ heat may be conv]t$ into me*anical effect4 ,?is absorb$ heat embraces 7,art4 #aaj7 two v>ieties ( en]gy1 "o ( ^! be+ molecul> motion1 & ! o!r molecul> en]gy ( position4 ,let u n[1 !re=e1 endeav\r to asc]ta9 "u :at circum/ances ! "o ( ^! v>ieties may be *ang$ into ! o!r4 ,x is well kn[n t x takes a good deal ( heat to conv]t a kilogramme ( ice into wat]1 & t :5 ! ice is melt$ ! temp]ature ( ! wat] is n p]ceptibly high] ?an t ( ! ice4 ,x is equally well kn[n t x takes a great deal ( heat to conv]t a kilogramme ( boil+ wat] into /eam1 & t :5 ! trans=mation is accompli%$1 ! /eam produc$ is n p]ceptibly hott] ?an ! boil+ wat]4 ,9 su* cases ! heat is said to become lat5t4 ,n[1 9 bo? ^! cases1 b m obvi\sly 9 ! la/1 we may suppose t ! heat has n _h its usual (fice to p]=m1 b t1 in/ead ( increas+ ! motion ( ! molecules ( wat]1 x has sp5t its en]gy 9 te>+ !m asund] f ea* o!r1 aga9/ ! =ce ( cohesion :i* b9ds !m toge!r4 ,inde$1 we "k z a matt] ( fact t ! =ce ( cohesion :i* is p]ceptible 9 boil+ wat] is app>5tly abs5t f /eam1 or ! vap\r ( wat]1 because its molecules are too remote f "o ano!r to all[ ( ?is =ce be+ appreciable4 ,we may1 !re=e1 suppose t a l>ge "p1 at lea/1 ( ! heat necess>y to conv]t boil+ wat] into /eam is sp5t 9 do+ "w aga9/ molecul> =ces4 ,:5 ! /eam is once m cond5s$ into hot wat]1 ! heat ?us sp5t reassumes ! =m ( molecul> motion1 & ! consequ5ce is t we require to take away someh[ all ! lat5t heat ( a kilogramme ( /eam be=e we c conv]t x into boil+ wat]4 ,9 fact1 if x is difficult & t$i\s to conv]t wat] into /eam1 x is difficult & t$i\s to conv]t /eam into wat]4 #aeh4 ,besides ! case n[ m5tion$1 !re are o!r in/ances 9 :i*1 no d\bt1 molecul> sep>ation becomes gradually *ang$ into heat motion4 ,?us1 :5 a piece ( glass has be5 sudd5ly cool$1 its p>ticles h n _h "t to acquire _! prop] position1 & ! consequ5ce is t ! :ole /ructure is ?r[n into a /ate ( con/ra9t4 ,9 ! c\rse ( "t su* bodies t5d to assume a m /able /ate1 & _! p>ticles gradually come clos] toge!r4 ,x is ow+ to ?is cause t ! bulb ( a !rmomet] rec5tly bl[n gradually contracts1 & x is no d\bt ow+ to ! same cause t a ,pr9ce ,rup]t's drop1 =m$ by dropp+ melt$ glass into wat]1 :5 brok51 falls into p[d] ) a k9d ( explosion4 ,x seems probable t 9 all su* cases ^! *anges are att5d$ ) heat1 & t !y d5ote ! conv]sion ( ! en]gy ( molecul> sep>ation into t ( molecul> motion4 #aei4 ,hav+ ?us exam9$ ! transmutations ( 7,c7 into 7,d71 & ( 7,d7 back aga9 into 7,c71 let u n[ proce$ ) our li/1 & see "u :at circum/ances absorb$ heat is *ang$ into *emical sep>ation4 ,x is well kn[n t :5 c]ta9 bodies are heat$1 !y are decompos$2 = in/ance1 if lime/one or c>bonate ( lime be heat$1 x is decompos$1 ! c>bonic acid be+ giv5 out 9 ! %ape ( gas1 :ile quick-lime rema9s beh9d4 ,n[1 heat is consum$ 9 ?is process1 t is to say1 a c]ta9 am\nt ( heat en]gy absolutely passes out ( exi/5ce z heat & is *ang$ into ! en]gy ( *emical sep>ation4 ,aga91 if ! lime s obta9$ be expos$1 "u c]ta9 circum/ances1 to an atmosph]e ( c>bonic acid1 x w gradually become *ang$ into c>bonate ( lime2 & 9 ?is *ange 7:i* is a gradual "o7 we may feel assur$ t ! en]gy ( *emical sep>ation is once m conv]t$ into ! en]gy ( heat1 al?\gh we may n p]ceive any increm5t ( temp]ature1 on acc\nt ( ! sl[ nature ( ! process4 ,at v high temp]atures x is possible t mo/ comp\nds are decompos$1 & ! temp]ature at :i* ?is takes place1 = any comp\nd1 has be5 t]m$ its temp]ature ( disassociation4 #afj4 ,heat en]gy is *ang$ into electrical sep>ation :5 t\rmal9es & c]ta9 o!r cry/als are heat$4 ,let u take1 = in/ance1 a cry/al ( t\rmal9e & raise its temp]ature1 & we %all f9d "o end positively1 & ! o!r negatively1 electrifi$4 ,aga91 let u take ! same cry/al1 & sudd5ly cool x1 & we %all f9d an electrification ( ! opposite k9d to ! =m]1 s t ! end ( ! axis1 :i* 0 !n positive1 w n[ be negative4 ,n[1 ?is sep>ation ( ! electricities d5otes en]gy2 & we h1 !re=e1 9 su* cry/als a case :]e ! en]gy ( heat has be5 *ang$ into t ( electrical sep>ation4 ,9 o!r words1 a c]ta9 am\nt ( heat has pass$ out ( exi/5ce z heat1 :ile 9 its place a c]ta9 am\nt ( electrical sep>ation has be5 obta9$4 #afa4 ,let u next see "u :at circum/ances heat is *ang$ into electricity 9 motion4 ,?is transmutation takes place 9 !rmo-electricity4 ,suppose1 = in/ance1 t we h a b> ( copp] or antimony1 say copp]1 sold]$ to a b> ( bismu?1 z 9 ,fig4 #ab4 ,let u n[ heat "o ( ! junctions1 :ile ! o!r rema9s cool4 ,x w be f\nd t a curr5t ( positive electricity circulates r\nd ! b>1 9 ! direction ( ! arr[-head1 go+ f ! bismu? to ! copp] across ! heat$ junction1 ! exi/5ce ( :i* may be detect$ by means ( a compass ne$le1 z we see 9 ! figure4 ,illu/ration3 ,fig4 #ab4 ,"h1 !n1 we h a case 9 :i* heat en]gy goes out ( exi/5ce1 & is conv]t$ into t ( an electric curr5t1 & we may ev5 arrange matt]s s z to make1 on ?is pr9ciple1 an in/rum5t :i* %all be an extremely delicate te/ ( ! exi/5ce ( heat4 ,by hav+ a numb] ( junctions ( bismu? & antimony1 z 9 ,fig4 #ac1 & heat+ ! upp] set1 :ile ! l[] rema9 cool1 we get a /rong curr5t go+ f ! bismu? to ! antimony across ! heat$ junctions1 & we may pass ! curr5t s produc$ r\nd ! wire ( a galvanomet]1 & ?us1 by increas+ ! numb] ( our junctions1 & also by us+ a v delicate galvanomet]1 we may get a v p]ceptible effect = ! smalle/ heat+ ( ! upp] junctions4 ,?is arrangem5t is call$ ! !rmopile1 &1 9 conjunction ) ! reflect+ galvanomet]1 x af=ds ! mo/ delicate means kn[n = detect+ small quantities ( heat4 ,illu/ration3 ,fig4 #ac4 #afb4 ,! la/ transmutation on our li/ ) respect to absorb$ heat is t 9 :i* ?is species ( en]gy is trans=m$ into radiant light & heat4 ,?is takes place :5ev] a hot body cools 9 an op5 space--! sun1 = in/ance1 p>ts ) a l>ge quantity ( 8 heat 9 ?is way2 & x is due1 9 "p at lea/1 to ?is process t a hot body cools 9 air1 & :olly to x t su* a body cools 9 vacuo4 ,x is1 moreov]1 due to ! p5etration ( our eye by radiant en]gy t we are able to see hot bodies1 & ?us ! v fact t we see !m implies t !y are p>t+ ) _! heat4 ,radiant en]gy moves ?r\gh space ) ! enorm\s velocity ( #ahh1jjj miles 9 "o second4 ,x takes ab\t eight m9utes to come f ! sun to our e>?1 s t if our lum9>y 7 to be sudd5ly ext+ui%$1 we %\ld h eight m9utes respite be=e ! cata/rophe ov]took u4 ,besides ! rays t affect ! eye1 !re are o!rs :i* we _c see1 & :i* may !re=e be t]m$ d>k rays4 ,a body1 = in/ance1 may n be hot en\gh to be self-lum9\s1 & yet x may be rapidly cool+ & *ang+ its heat into radiant en]gy1 :i* is giv5 (f by ! body1 ev5 al?\gh nei!r ! eye nor ! t\* may be compet5t to detect x4 ,x may nev]!less be detect$ by ! !rmopile1 :i* 0 describ$ 9 ,art4 #afa4 ,we ?us see h[ /rong is ! lik5ess betwe5 a heat$ body & a s\nd+ "o4 ,= j z a s\nd+ body gives out "p ( its s\nd en]gy to ! atmosph]e ar\nd x1 s does a heat$ body give out "p ( its heat en]gy to ! e!real m$ium ar\nd x4 ,:51 h[ev]1 we consid] ! rates ( motion ( ^! en]gies ?r\gh _! respective m$ia1 !re is a mighty diff]5ce betwe5 ! two1 s\nd travell+ ?r\gh ! air ) ! velocity ( #aajj feet a second1 :ile radiant en]gy moves ov] no less a space ?an #ahh1jjj miles 9 ! same portion ( "t4 ,*emical ,sep>ation4 #afc4 ,we n[ come to ! en]gy d5ot$ by *emical sep>ation1 su* z we possess :5 we h coal or c>bon 9 "o place1 & oxyg5 9 ano!r4 ,v evid5tly ?is =m ( en]gy ( position is transmut$ into heat :5 we burn ! coal1 or cause x to comb9e ) ! oxyg5 ( ! air2 & g5]ally1 :5ev] *emical comb9ation takes place1 we h ! production ( heat1 ev5 al?\gh o!r circum/ances may int]f]e to prev5t its recognition4 ,n[1 9 accordance ) ! pr9ciple ( cons]vation1 x may be expect$ t1 if a def9ite quantity ( c>bon or ( hydrog5 be burn$ "u giv5 circum/ances1 !re w be a def9ite production ( heat2 t is to say1 a ton ( coals or ( coke1 :5 burn$1 w give u s _m heat units1 & nei!r m or less4 ,we may1 no d\bt1 burn our ton 9 su* a way z to economize m or less ( ! heat produc$2 b1 z f> z ! m]e production ( heat is conc]n$1 if ! quantity & quality ( ! mat]ial burn$ & ! circum/ances ( combu/ion be ! same1 we expect ! same am\nt ( heat4 #afd4 ,! foll[+ table1 d]iv$ f ! rese>*es ( ,&rews1 & ^? ( ,favre & ,silb]mann1 %[s u h[ _m units ( heat we may get by burn+ a kilogramme ( v>i\s sub/ances4 ,,units ( ,,heat develop$ by ,,combu/ion 9 ,,oxyg54 ,kilogrammes ( ,wat] rais$ #a ,c4 ,sub/ance by ! combu/ion ( "o kilogramme ,burn$4 ( ea* sub/ance4 ,hydrog5 #cd1ace ,c>bon #g1iij ,sulphur #b1bfc ,phosphorus #e1gdg ,z9c #a1cja ,iron #a1egf ,t9 #a1bcc ,olefiant ,gas #aa1ijj ,alcohol #g1jaf #afe4 ,!re are o!r me?ods1 besides combu/ion1 by :i* *emical comb9ation takes place4 ,:51 = in/ance1 we plunge a piece ( metallic iron into a solution ( copp]1 we f9d t :5 we take x out1 its surface is cov]$ ) copp]4 ,"p ( ! iron has be5 dissolv$1 tak+ ! place ( ! copp]1 :i* has !re=e be5 ?r[n1 9 its metallic /ate1 ^u ! surface ( ! iron4 ,n[1 9 ?is op]ation heat is giv5 out--we h 9 fact burn$1 or oxidiz$1 ! iron1 & we are ?us furni%$ ) a means ( arrang+ ! metals1 beg9n+ ) t :i* gives out mo/ heat1 :5 us$ to displace ! metal at ! o!r extremity ( ! s]ies4 #aff4 ,! foll[+ li/ has be5 =m$1 on ?is pr9ciple1 by ,dr4 ,&rews3-- #a4 ,z9c #b4 ,iron #c4 ,lead #d4 ,copp] #e4 ,m]cury #f4 ,silv] #g4 ,plat9um --t is to say1 ! metal plat9um c be displac$ by any o!r metal ( ! s]ies1 b we %all get mo/ heat if we use z9c to displace x4 ,we may !re=e assume t if we displace a def9ite quantity ( plat9um by a def9ite quantity ( z9c1 we %all get a def9ite am\nt ( heat4 ,suppose1 h[ev]1 t in/ead ( p]=m+ ! op]ation 9 "o /ep1 we make two ( x4 ,let u1 = in/ance1 fir/ ( all displace copp] by means ( z9c1 & !n plat9um by means ( copp]4 ,is x n possible t ! "o ( ^! processes may be m fruitful 9 heat giv+ ?an ! o!r8 ,n[1 ,&rews has %[n u t we _c ga9 an advantage ov] ,nature 9 ?is way1 & t if we use our z9c fir/ ( all to displace iron1 or copp]1 or lead1 & !n use ?is metal to displace plat9um1 we %all obta9 j ! v same am\nt ( heat z if we _h us$ ! z9c to displace ! plat9um at once4 #afg4 ,x ought "h to be m5tion$ t1 v g5]ally1 *emical action is accompani$ ) a *ange ( molecul> condition4 ,a solid1 = in/ance1 may be *ang$ into a liquid1 or a gas into a liquid4 ,sometimes ! "o *ange c\nt]acts ! o!r z f> z app>5t heat is conc]n$2 b sometimes1 too1 !y co-op]ate toge!r to increase ! result4 ,?us1 :5 a gas is absorb$ by wat]1 mu* heat is evolv$1 & we may suppose ! result to be due 9 "p to *emical comb9ation1 & 9 "p to ! cond5sation ( ! gas into a liquid1 by :i* means its lat5t heat is r5d]$ s5sible4 ,on ! o!r h&1 :5 a liquid unites ) a solid1 or :5 two solids unite ) "o ano!r1 & ! product is a liquid1 we h v (t5 ! absorption ( heat1 ! heat r5d]$ lat5t by ! dissolution ( ! solid be+ m ?an t g5]at$ by comb9ation4 ,freez+ mixtures owe _! cool+ prop]ties to ?is cause2 ?us1 if sn[ & salt be mix$ toge!r1 !y liquefy ea* o!r1 & ! result is br9e ( a temp]ature mu* l[] ?an t ( ei!r ! +r$i5ts4 #afh4 ,:5 het]og5e\s metals1 su* z z9c & copp]1 are sold]$ toge!r1 we h app>5tly a conv]sion ( ! en]gy ( *emical sep>ation into t ( electrical sep>ation4 ,?is 0 fir/ sugge/$ by ,volta z ! orig9 ( ! electrical sep>ation :i* we see 9 ! voltaic curr5t1 & rec5tly its exi/5ce has be5 di/9ctly prov$ by ,sir ,w4 ,?omson4 ,to r5d] manife/ ?is conv]sion ( en]gy1 let u sold] a piece ( z9c & copp] toge!r--if we n[ te/ ! b> by means ( a delicate electromet] we %all f9d t ! z9c is positively1 :ile ! copp] is negatively1 electrifi$4 ,we h "h1 !re=e1 an in/ance ( ! transmutation ( "o =m ( en]gy ( position into ano!r2 s mu* en]gy ( *emical sep>ation disappe>+ 9 ord] to produce s mu* electrical sep>ation4 ,?is expla9s ! fact record$ 9 ,art4 #ic1 :]e we saw t if a batt]y be insulat$ & its poles kept ap>t1 ! "o w be *>g$ ) positive1 & ! o!r ) negative1 electricity4 #afi4 ,b fur!r1 :5 su* a voltaic batt]y is 9 action1 we h a transmutation ( *emical sep>ation into electricity 9 motion4 ,to see ?is1 let u consid] :at takes place 9 su* a batt]y4 ,"h no d\bt ! s\rces ( electrical excitem5t are ! po9ts ( contact ( ! z9c & plat9um1 :]e1 z we see by our la/ article1 we h electrical sep>ation produc$4 ,b ?is ( itself w\ld n produce a curr5t1 = an electrical curr5t implies v consid]able en]gy1 & mu/ be f$ by some?+4 ,n[1 9 ! voltaic batt]y we h two ?+s :i* accompany ea* o!r1 & :i* are manife/ly connect$ toge!r4 ,9 ! fir/ place we h ! combu/ion1 or at lea/ ! oxidation & dissolution1 ( ! z9c2 & we h1 secondly1 ! production ( a p[]ful curr5t4 ,n[1 evid5tly1 ! fir/ ( ^! is t :i* fe$s ! second1 or1 9 o!r words1 ! en]gy ( *emical sep>ation ( ! metallic z9c is transmut$ into t ( an electrical curr5t1 ! z9c be+ virtually burn$ 9 ! process ( transmutation4 #agj4 ,f9ally1 z f> z we are aw>e1 ! en]gy ( *emical sep>ation is n directly transmut$ into radiant light & heat4 ,electrical ,sep>ation4 #aga4 ,9 ! fir/ place ! en]gy ( electrical sep>ation is obvi\sly transmut$ into t ( visible motion1 :5 two oppositely electrifi$ bodies approa* ea* o!r4 #agb4 ,aga91 x is transmut$ into a curr5t ( electricity1 & ultimately into heat1 :5 a sp>k passes betwe5 two oppositely electrifi$ bodies4 ,x ought1 !re=e1 to be borne 9 m9d t :5 ! fla% is se5 !re is no long] electricity1 :at we see be+ m]ely air1 or "s o!r mat]ial1 int5sely heat$ by ! dis*>ge4 ,?us a man might be r5d]$ ins5sible by a fla% ( lightn+ )\t 8 see+ ! fla%--= ! effect ( ! dis*>ge ^u ! man1 & its effect 9 heat+ ! air1 might be ph5om5a s ne>ly simultane\s t ! man might become ins5sible be=e he c\ld p]ceive ! fla%4 ,electricity 9 ,motion4 #agc4 ,?is en]gy is transmut$ into t ( visible motion :5 two wires convey+ electrical curr5ts 9 ! same direction attract ea* o!r4 ,:51 = in/ance1 two circul> curr5ts float on wat]1 bo? go+ 9 ! direction ( ! h&s ( a wat*1 we h se5 f ,art4 #ajj t !y w move t[>ds ea* o!r4 ,n[1 "h !re is1 9 tru?1 a less5+ ( ! int5sity ( ea* curr5t :5 ! motion is tak+ place1 = we "k 7,art4 #ajd7 t :5 a circuit is mov$ into ! pres5ce ( ano!r circuit convey+ a curr5t1 !re is produc$ by induction a curr5t 9 ! opposite direction2 & h5ce we p]ceive t1 :5 two simil> curr5ts approa* ea* o!r1 ea* is dim9i%$ by means ( ?is inductive influ5ce--9 fact1 a c]ta9 am\nt ( curr5t en]gy disappe>s f exi/5ce 9 ord] t an equival5t am\nt ( ! en]gy ( visible motion may be produc$4 #agd4 ,electricity 9 motion is transmut$ into heat dur+ ! passage ( a curr5t along a ?9 wire1 or any badly conduct+ sub/ance--! wire is heat$ 9 consequ5ce1 & may ev5 become :ite hot4 ,mo/ frequ5tly ! en]gy ( an electric curr5t is sp5t 9 heat+ ! wires & o!r mat]ials t =m ! circuit4 ,n[1 ! en]gy ( su* a curr5t is f$ by ! burn+ or oxidation ( ! metal 7g5]ally z9c7 :i* is us$ 9 ! circuit1 s t ! ultimate effect ( ?is combu/ion is ! heat+ ( ! v>i\s wires & o!r mat]ials ?r\gh :i* ! curr5t passes4 #age4 ,we may1 9 tru?1 burn or oxidize z9c 9 two ways--we may oxidize x1 z we h j se51 9 ! voltaic batt]y1 & we %all f9d t by ! combu/ion ( a kilogramme ( z9c a def9ite am\nt ( heat is produc$4 ,or we may oxidize our z9c by dissolv+ x 9 acid 9 a s+le vessel1 :51 )\t go+ ?r\gh ! int]m$iate process ( a curr5t1 we %all get j z mu* heat out ( a kilogramme ( z9c z we did 9 ! =m] case4 ,9 fact1 :e!r we oxidize our z9c by ! batt]y1 or 9 ! ord9>y way1 ! quantity ( heat produc$ w always be> ! same relation to ! quantity ( z9c consum$2 ! only diff]5ce be+ t1 9 ! ord9>y way ( oxidiz+ z9c1 ! heat is g5]at$ 9 ! vessel conta9+ ! z9c & acid1 :ile 9 ! batt]y x may make its appe>ance a ?\s& miles away1 if we h a suffici5tly long wire to convey our curr5t4 #agf4 ,?is is1 p]haps1 ! "r place = allud+ to a discov]y ( ,pelti]1 t a curr5t ( positive electricity pass+ across a junction ( bismu? & antimony 9 ! direction f ! bismu? to ! antimony appe>s to produce cold4 ,illu/ration3 ,fig4 #ad4 ,to und]/& ! significance ( ?is fact we mu/ consid] x 9 connection ) ! !rmo-electric curr5t1 :i* we h se51 f ,art4 #afa1 is e/abli%$ 9 a circuit ( bismu? & antimony1 ( :i* "o junction is hott] ?an ! o!r4 ,suppose we h a circuit ( ?is k9d ) bo? its junctions at ! temp]ature ( #ajj ,c4 to beg9 )4 ,suppose1 next1 t :ile we protect "o junction1 we expose ! o!r to ! op5 air--x w1 ( c\rse1 lose heat1 s t ! protect$ junction w n[ be hott] ?an ! o!r4 ,! consequ5ce w be 7,art4 #afa7 t a curr5t ( positive electricity w pass along ! protect$ junction f ! bismu? to ! antimony4 ,n[1 "h we h an app>5t anomaly1 = ! circuit is cool+--t is to say1 x is los+ en]gy--b at ! v same "t x is manife/+ en]gy 9 ano!r %ape1 namely1 9 t ( an electric curr5t1 :i* is circulat+ r\nd x4 ,cle>ly1 !n1 "s ( ! heat ( ?is circuit mu/ be sp5t 9 g5]at+ ?is curr5t2 9 fact1 we %\ld expect ! circuit to act z a heat eng9e1 only produc+ curr5t en]gy in/ead ( me*anical en]gy1 & h5ce 7,art4 #aeb7 we %\ld expect to see a conveyance ( heat f ! hott] to ! cold] p>ts ( ! circuit4 ,n[1 ?is is precisely :at ! curr5t does1 =1 pass+ along ! hott] junction1 9 ! direction ( ! arr[-head1 x cools t junction1 & heats ! cold] "o at ,c1--9 o!r words1 x c>ries heat f ! hott] to ! cold] p>ts ( ! circuit4 ,we %\ld h be5 v mu* surpris$ _h su* a curr5t cool$ ,c & heat$ ,h1 = !n we %\ld h _h a manife/ation ( curr5t en]gy1 accompani$ ) ! conveyance ( heat f a cold] to a hott] sub/ance1 :i* is aga9/ ! pr9ciple ( ,art4 #aeb4 #agg4 ,f9ally1 ! en]gy ( electricity 9 motion is conv]t$ into t ( *emical sep>ation1 :5 a curr5t ( electricity is made to decompose a body4 ,"p ( ! en]gy ( ! curr5t is sp5t 9 ?is process1 & we %all get s mu* less heat f x 9 consequ5ce4 ,suppose1 = in/ance1 t by oxidiz+ s mu* z9c 9 ! batt]y we get1 "u ord9>y circum/ances1 #ajj units ( heat4 ,let u1 h[ev]1 set ! batt]y to decompose wat]1 & we %all probably f9d t by oxidiz+ ! same am\nt ( z9c we get n[ only #hj units ( heat4 ,cle>ly1 !n1 ! defici5cy or #bj units h gone to decompose ! wat]4 ,n[1 if we explode ! mix$ gases :i* are ! result ( ! decomposition1 we %all get back ^! #bj units ( heat precisely1 & nei!r m nor less2 & ?us we see t amid all su* *anges ! quantity ( en]gy rema9s ! same4 ,radiant ,en]gy4 #agh4 ,?is =m ( en]gy is conv]t$ into absorb$ heat :5ev] x falls ^u an opaque sub/ance--"s ( x1 h[ev]1 is g5]ally convey$ away by reflexion1 b ! rema9d] is absorb$ by ! body1 & consequ5tly heats x4 ,x is a curi\s "q to ask :at becomes ( ! radiant light f ! sun t is n absorb$ ei!r by ! planets ( our sy/em1 or by any ( ! />s4 ,we c only reply to su* a "q1 t z f> z we c judge f our pres5t k1 ! radiant en]gy t is n absorb$ mu/ be conceiv$ to be trav]s+ space at ! rate ( #ahh1jjj miles a second4 #agi4 ,!re is only "o m transmutation ( radiant en]gy t we "k (1 & t is :5 x promotes *emical sep>ation4 ,?us1 c]ta9 rays ( ! sun are kn[n to h ! p[] ( decompos+ *loride ( silv]1 & o!r *emical comp\nds4 ,n[1 9 all su* cases !re is a transmutation ( radiant en]gy into t ( *emical sep>ation4 ,! sun's rays1 too1 decompose c>bonic acid 9 ! leaves ( plants1 ! c>bon go+ to =m ! woody fibre ( ! plant1 :ile ! oxyg5 is set free into ! air2 & ( c\rse a c]ta9 proportion ( ! en]gy ( ! sol> rays is consum$ 9 promot+ ?is *ange1 & we h s mu* less heat+ effect 9 consequ5ce4 ,b all ! sol> rays h n ?is p[]--= ! prop]ty ( promot+ *emical *ange is conf9$ to ! blue & violet rays1 & "s o!rs :i* are n visible to ! eye4 ,n[1 ^! rays are entirely abs5t f ! radiation ( bodies at a comp>atively l[ temp]ature1 su* z an ord9>y r$ heat1 s t a photograph] w\ld f9d x impossible to obta9 ! picture ( a r$-hot body1 ^: only light 0 9 itself4 #ahj4 ,! act9ic1 or *emically active1 rays ( ! sun decompose c>bonic acid 9 ! leaves ( plants1 & !y disappe> 9 consequ5ce1 or are absorb$2 ?is may1 !re=e1 be ! reason :y v few su* rays are ei!r reflect$ or transmitt$ f a sun-lit leaf1 9 consequ5ce ( :i* ! photograph] f9ds x difficult to obta9 an image ( su* a leaf2 9 o!r words1 ! rays :i* w\ld h produc$ a *emical *ange on 8 photographic plate h all be5 us$ up by ! leaf = peculi> purposes ( its own4 #aha4 ,& "h x is important to be> 9 m9d t :ile animals 9 ! act ( brea?+ consume ! oxyg5 ( ! air1 turn+ x into c>bonic acid1 plants1 on ! o!r h&1 re/ore ! oxyg5 to ! air2 ?us ! two k+doms1 ! animal & ! vegetable1 "w into ea* o!r's h&s1 & ! purity ( ! atmosph]e is kept up4 ,,footnotes3 #d ,?is explanation 0 fir/ giv5 by ,pr(essors ,?omson & ,tait 9 _! ,natural ,philosophy1 & by ,dr4 ,frankl& 9 a lecture at ! ,royal ,in/itution ( ,london4 #e ,see ,de ,la ,rue1 ,/ew>t1 & ,loewy's rese>*es on ,sol> ,physics4 #f ,see ! ,magnetic ,rese>*es ( ,sir ,e4 ,sab9e1 also ,c4 ,meldrum on ! ,p]iodicity ( ,cyclones4 ,,*apt] ,v4 ,,hi/orical ,,sket*3 ,,! ,,dissipation ,,( ,,en]gy4 #ahb4 ,9 ! la/ *apt] we h endeav\r$ to exhibit ! v>i\s transmutations ( en]gy1 &1 :ile do+ s1 to br+ =w>d evid5ce 9 fav\r ( ! !ory ( cons]vation1 %[+ t x enables u to c\ple toge!r kn[n laws1 & also to discov] new ones--%[+1 9 f9e1 t x be>s ab\t ) x all ! m>ks ( a true hypo!sis4 ,x may n[1 p]haps1 be in/ructive1 to look back & endeav\r to trace ! progress ( ?is great conception1 f its fir/ beg9n+ among ! anci5ts1 up to its triumphant e/abli%m5t by ! lab\rs ( ,j\le & 8 fell[-work]s4 #ahc4 ,ma!maticians in=m u t if matt] consi/s ( atoms or small p>ts1 :i* are actuat$ by =ces dep5d+ only ^u ! di/ances betwe5 ^! p>ts1 & n ^u ! velocity1 !n x may be demon/rat$ t ! law ( cons]vation ( en]gy w hold good4 ,?us we see t conceptions reg>d+ atoms & _! =ces are alli$ to conceptions reg>d+ en]gy4 ,a m$ium ( "s sort p]vad+ space seems also necess>y to our !ory4 ,9 f9e1 a univ]se compos$ ( atoms1 ) "s sort ( m$ium betwe5 !m1 is to be reg>d$ z ! ma*9e1 & ! laws ( en]gy z ! laws ( work+ ( ?is ma*9e4 ,x may be t a !ory ( atoms ( ?is sort1 ) a m$ium betwe5 !m1 is n aft] all ! simple/1 b we are probably n yet prep>$ = any m g5]al hypo!sis4 ,n[1 we h only to look to our own sol> sy/em1 9 ord] to see on a l>ge scale an illu/ration ( ?is conception1 = !re we h ! v>i\s heav5ly bodies attract+ "o ano!r1 ) =ces dep5d+ only on ! di/ances betwe5 !m1 & indep5d5t ( ! velocities2 & we h likewise a m$ium ( "s sort1 9 virtue ( :i* radiant en]gy is convey$ f ! sun to ! e>?4 ,p]haps we %all n greatly err if we reg>d a molecule z repres5t+ on a small scale some?+ analog\s to ! sol> sy/em1 :ile ! v>i\s atoms :i* con/itute ! molecule may be lik5$ to ! v>i\s bodies ( ! sol> sy/em4 ,! %ort hi/orical sket* :i* we are ab\t to give w embrace1 !re=e1 along ) en]gy1 ! progress ( ?\ght & speculation ) respect to atoms & also ) respect to a m$ium1 inasmu* z ^! subjects are intimately connect$ ) ! doctr9es ( en]gy4 ,h]aclitus on ,en]gy4 #ahd4 ,h]aclitus1 :o fl\ri%$ at ,ephesus1 ,b4,c4 #ejj1 decl>$ t fire 0 ! great cause1 & t all ?+s 7 9 a p]petual flux4 ,su* an expression w no d\bt be reg>d$ z v vague 9 ^! days ( precise physical /atem5ts2 & yet x seems cle> t ,h]aclitus mu/ h _h a vivid conception ( ! innate re/lessness & en]gy ( ! univ]se1 a conception alli$ 9 "* to1 & only less precise ?an t ( mod]n philosoph]s1 :o reg>d matt] z ess5tially dynamical4 ,democritus on ,atoms4 #ahe4 ,democritus1 :o 0 born #dgj ,b4,c41 0 ! orig9ator ( ! doctr9e ( atoms1 a doctr9e :i* 9 ! h&s ( ,john ,dalton has enabl$ ! human m9d to lay hold ( ! laws :i* regulate *emical *anges1 z well z to picture to itself :at is !re tak+ place4 ,p]haps !re is no doctr9e t has n[adays a m intimate connection ) ! indu/ries ( life ?an ?is ( atoms1 & x is probable t no intellig5t director ( *emical indu/ry among civiliz$ nations fails to picture to 8 own m9d1 by means ( ?is doctr9e1 ! inn] nature ( ! *anges :i* he sees ) 8 eyes4 ,n[1 x is a curi\s circum/ance t ,bacon %\ld h light$ ^u ?is v doctr9e ( atoms1 9 ord] to po9t "o ( 8 philosophical morals4 8,nor is x less an evil0 7says he71 8t 9 _! philosophies & contemplations m5 sp5d _! lab\r 9 inve/igat+ & treat+ ( ! fir/ pr9ciples ( ?+s1 & ! extreme limits ( nature1 :5 all t is useful & ( avail 9 op]ation is to be f\nd 9 :at is int]m$iate4 ,h5ce x happ5s t m5 cont9ue to ab/ract ,nature till !y arrive at pot5tial & un=m$ matt]2 & aga9 !y cont9ue to divide ,nature1 until !y h arriv$ at ! atom2 ?+s :i*1 ev5 if true1 c be ( little use 9 help+ on ! =tunes ( m540 ,surely we ought to le>n a lesson f ^! rem>ks ( ! great ,fa!r ( exp]im5tal sci5ce1 & be v cauti\s be=e we dismiss any bran* ( k or tra9 ( ?\ght z ess5tially unpr(itable4 ,ari/otle on a ,m$ium4 #ahf4 ,z reg>ds ! exi/5ce ( a m$ium1 x is rem>k$ by ,:ewell t ! anci5ts also caught a glimpse ( ! idea ( a m$ium1 by :i* ! qualities ( bodies1 z col\rs & s\nds are p]ceiv$1 & he quotes ! foll[+ f ,ari/otle3-- 8,9 a void !re c\ld be no diff]5ce ( up & d[n2 =1 z 9 no?+ !re are no diff]5ces1 s !re are none 9 a privation or negation40 ,^u ?is ! hi/orian ( sci5ce rem>ks1 8,x is easily se5 t su* a mode ( reason+ elevates ! famili> =ms ( language1 & ! intellectual connexions ( t]ms1 to a supremacy ov] facts40 ,nev]!less1 may x n be repli$ t our conceptions ( matt] are d$uc$ f ! famili> exp]i5ce1 t c]ta9 portions ( space affect u 9 a c]ta9 mann]2 &1 consequ5tly1 are we n entitl$ to say !re mu/ be some?+ :]e we exp]i5ce ! diff]5ce ( up or d[n8 ,is !re1 aft] all1 a v great diff]5ce betwe5 ?is argum5t & t ( mod]n physici/s 9 fav\r ( a pl5um1 :o tell u t matt] _c act :]e x is n8 ,ari/otle seems also to h ent]ta9$ ! idea t light is n any body1 or ! emanation ( any body 7= t1 he says1 w\ld be a k9d ( body71 & t !re=e light is an en]gy or act4 ,! ,ideas ( ! ,anci5ts 7 n ,prolific4 #ahg4 ,^! quotations r5d] x evid5t t ! anci5ts _h1 9 "s way1 grasp$ ! idea ( ! ess5tial unre/ & en]gy ( ?+s4 ,!y _h also ! idea ( small p>ticles or atoms1 &1 f9ally1 ( a m$ium ( "s sort4 ,& yet ^! ideas 7 n prolific--!y gave rise to no?+ new4 ,n[1 :ile ! hi/orian ( sci5ce is unque/ionably "r 9 8 criticism ( ! anci5ts1 t _! ideas 7 n di/9ct & appropriate to ! facts1 yet we h se5 t !y 7 n :olly ignorant ( ! mo/ pr(\nd & deeply-seat$ pr9ciples ( ! mat]ial univ]se4 ,9 ! great hymn *ant$ by ,nature1 ! fundam5tal notes 7 e>ly he>d1 b yet x requir$ long c5turies ( pati5t wait+ = ! practis$ e> ( ! skill$ musician to appreciate ! mighty h>mony aright4 ,or1 p]haps1 ! attempts ( ! anci5ts 7 z ! sket*es ( a *ild :o j contrives to exhibit1 9 a rude way1 ! lead+ outl9es ( a build+2 :ile ! conceptions ( ! practis$ physici/ are m alli$ to ^? ( ! ar*itect1 or1 at lea/1 ( "o :o has realiz$1 to "s ext5t1 ! ar*itect's views4 #ahh4 ,! anci5ts possess$ great g5ius & intellectual p[]1 b !y 7 defici5t 9 physical conceptions1 &1 9 consequ5ce1 _! ideas 7 n prolific4 ,x _c inde$ be said t we ( ! pres5t age are defici5t 9 su* conceptions2 nev]!less1 x may be que/ion$ :e!r !re is n a t5d5cy to ru% into ! opposite extreme1 & to "w physical conceptions to an excess4 ,let u be cauti\s t 9 avoid+ ,scylla1 we d n ru% into ,*>ybdis4 ,= ! univ]se has m ?an "o po9t ( view1 & !re are possibly regions :i* w n yield _! treasures to ! mo/ det]m9$ physici/s1 arm$ only ) kilogrammes & metres & /&>d clocks4 ,desc>tes1 ,newton1 & ,huygh5s on a ,m$ium4 #ahi4 ,9 mod]n times ,desc>tes1 au?or ( ! v]tical hypo!sis1 necess>ily presuppos$ ! exi/5ce ( a m$ium 9 int]-planet>y spaces1 b on ! o!r h& he 0 "o ( ! orig9ators ( t idea :i* reg>ds light z a s]ies ( p>ticles %ot out f a lum9\s body4 ,newton likewise conceiv$ ! exi/5ce ( a m$ium1 al?\gh he became an advocate ( ! !ory ( emission4 ,x is to ,huygh5s t ! cr$it belongs ( hav+ fir/ conceiv$ ! undulatory !ory ( light ) suffici5t di/9ctness to acc\nt = d\ble refraction4 ,aft] him1 ,"y1 ,fresnel1 & _! foll[]s1 h greatly develop$ ! !ory1 enabl+ x to acc\nt = ! mo/ complicat$ & wond]ful ph5om5a4 ,bacon on ,heat4 #aij4 ,) reg>d to ! nature ( heat1 ,bacon1 :atev] may be ?\ght ( 8 argum5ts1 seems cle>ly to h recogniz$ x z a species ( motion4 ,he says1 8,f ^! in/ances1 view$ toge!r & individually1 ! nature ( :i* heat is ! limitation seems to be motion20 & aga9 he says1 8,b :5 we say ( motion t x /&s 9 ! place ( a g5us to heat1 we mean to convey1 n t heat g5]ates motion or motion heat 7al?\gh ev5 bo? may be true 9 "s cases71 b t ess5tial heat is motion & no?+ else40 ,nev]!less x requir$ ne>ly ?ree c5turies be=e ! true !ory ( heat 0 suffici5tly root$ to develop into a productive hypo!sis4 ,pr9ciple ( ,virtual ,velocities4 #aia4 ,9 a previ\s *apt] we h already detail$ ! lab\rs 9 respect ( heat ( ,davy1 ,rum=d1 & ,j\le4 ,galileo & ,newton1 if !y1 did n grasp ! dynamical nature ( heat1 _h yet a cle> conception ( ! functions ( a ma*9e4 ,! =m] saw t :at we ga9 9 p[] we lose 9 space2 :ile ! latt] w5t fur!r1 & saw t a ma*9e1 if left to itself1 is /rictly limit$ 9 ! am\nt ( "w :i* x c accompli%1 al?\gh its en]gy may v>y f t ( motion to t ( position1 & back aga91 accord+ to ! geometric laws ( ! ma*9e4 ,rise ( true ,conceptions reg>d+ ,"w4 #aib4 ,!re c1 we ?9k1 be no "q t ! great developm5t ( indu/rial op]ations 9 ! pres5t age has indirectly fur!r$ our conceptions reg>d+ "w4 ,humanity inv>iably /rives to escape z mu* z possible f h>d "w4 ,9 ! days ( old ^? :o _h ! p[] got slaves to "w = !m2 b ev5 !n ! ma/] _h to give "s k9d ( equival5t = ! "w done4 ,= at ! v l[e/ a slave is a ma*9e1 & mu/ be f$1 & is moreov] apt to prove a v tr\blesome ma*9e if n prop]ly dealt )4 ,! great improvem5ts 9 ! /eam eng9e1 introduc$ by ,watt1 h done z mu*1 p]haps1 z ! abolition ( slav]y to b5efit ! work+ man4 ,! h>d "w ( ! _w has be5 put ^u iron %\ld]s1 t d n sm>t2 &1 9 consequ5ce1 we h _h an imm5se ext5sion ( indu/ry1 & a great amelioration 9 ! position ( ! l[] classes ( mank9d4 ,b if we h transf]r$ our h>d "w to ma*9es1 x is necess>y to "k h[ to "q a ma*9e--h[ to say to x1 ,at :at rate c y lab\r8 h[ mu* "w c y turn out 9 a day8 ,x is necess>y1 9 fact1 to h ! cle>e/ possible idea ( :at "w is4 ,our read]s w see f all ?is t m5 are n likely to err 9 _! me?od ( measur+ "w4 ,! pr9ciples ( measurem5t h be5 /amp$ z x 7 ) a br& into ! v he>t & bra9 ( humanity4 ,to ! employ] ( ma*9]y or ( human lab\r1 a false me?od ( measur+ "w simply means ru92 he is likely1 !re=e1 to take ! greate/ possible pa9s to arrive at accuracy 9 8 det]m9ation4 ,p]petual ,motion4 #aic4 ,n[1 amid ! cr[d ( work]s sm>t+ f ! curse ( lab\r1 !re rises up e n[ & !n an en?usia/1 :o seeks to escape by means ( an artifice f ?is insupportable tyranny ( "w4 ,:y n con/ruct a ma*9e t w g on giv+ y "w )\t limit )\t ! necessity ( be+ f$ 9 any way4 ,nature mu/ h "s weak po9t 9 h] arm\r2 !re mu/ surely be "s way ( gett+ r\nd h]2 %e is only tyrann\s on ! surface1 & 9 ord] to /imulate our +5uity1 b w yield ) pleasure to ! p]si/5ce ( g5ius4 ,n[1 :at c ! man ( sci5ce say to su* an en?usia/8 ,he _c tell him t he is intimately acqua9t$ ) all ! =ces ( ,nature1 & c prove t p]petual motion is impossible2 =1 9 tru?1 he kn[s v little ( ^! =ces4 ,b he does ?9k t he has ent]$ into ! _s & design ( ,nature1 & !re=e he d5ies at once ! possibility ( su* a ma*9e4 ,b he d5ies x intellig5tly1 & works out ?is d5ial ( 8 into a !ory :i* enables him to discov] num]\s & valuable relations betwe5 ! prop]ties ( matt]--produces1 9 fact1 ! laws ( en]gy & ! great pr9ciple ( cons]vation4 ,!ory ( ,cons]vation4 #aid4 ,we h ?us endeav\r$ to give a %ort sket* ( ! hi/ory ( en]gy1 includ+ its alli$ problems1 up to ! dawn ( ! /rictly sci5tific p]iod4 ,we h se5 t ! unfruitfulness ( ! e>li] views 0 due to a want ( sci5tific cle>ness 9 ! conceptions ent]ta9$1 & we h n[ to say a few words reg>d+ ! !ory ( cons]vation4 ,"h also ! way 0 po9t$ out by two philosoph]s1 namely1 ,grove 9 ?is c\ntry1 & ,may] on ! cont95t1 :o %[$ c]ta9 relations betwe5 ! v>i\s =ms ( en]gy2 ! "n ( ,sgu9 ought likewise to be m5tion$4 ,nev]!less1 to ,j\le belongs ! hon\r ( e/abli%+ ! !ory on an incontrov]tible basis3 =1 inde$1 ?is is preem95tly a case :]e speculation has to be te/$ by unimpea*able exp]im5tal evid5ce4 ,"h ! magnitude ( ! pr9ciple is s va/1 & its importance is s great1 t x requires ! /rong fire ( g5ius1 jo9$ to ! pati5t lab\rs ( ! sci5tific exp]im5tali/1 to =ge ! r\gh ore into a good weapon t w cleave its way ?r\gh all ob/acles into ! v citadel ( ,nature1 & into h] mo/ secret recesses4 ,foll[+ closely ^u ! lab\rs ( ,j\le1 we h ^? ( ,william & ,james ,?omson1 ,helmholtz1 ,rank9e1 ,clausius1 ,tait1 ,&rews1 ,maxwell1 :o1 along ) _m o!rs1 h advanc$ ! subject2 & :ile ,j\le gave 8 *ief att5tion to ! laws :i* regulate ! transmutation ( me*anical en]gy into heat1 ,?omson1 ,rank9e1 & ,clausius gave !irs to ! conv]se problem1 or t :i* relates to ! transmutation ( heat into me*anical en]gy4 ,?omson1 especially1 has pu%$ =w>d s resolutely f ?is po9t ( view t he has succe$$ 9 grasp+ a pr9ciple sc>cely inf]ior 9 importance to t ( ! cons]vation ( en]gy itself1 & ( ?is pr9ciple x behoves u n[ to speak4 ,dissipation ( ,en]gy4 #aie4 ,j\le1 we h said1 prov$ ! law accord+ to :i* "w may be *ang$ into heat2 & ,?omson & o!rs1 t accord+ to :i* heat may be *ang$ into "w4 ,n[1 x occurr$ to ,?omson t !re 0 a v important & significant diff]5ce betwe5 ^! two laws1 consi/+ 9 ! fact t1 :ile y c ) ! greate/ ease trans=m "w into heat1 y c by no me?od 9 y\r p[] trans=m all ! heat back aga9 into "w4 ,9 fact1 ! process is n a rev]sible "o2 & ! consequ5ce is t ! me*anical en]gy ( ! univ]se is becom+ e day m & m *ang$ into heat4 ,x is easily se5 t if ! process 7 rev]sible1 "o =m ( a p]petual motion w\ld n be impossible4 ,=1 )\t attempt+ to create en]gy by a ma*9e1 all t w\ld be ne$$ = a p]petual motion w\ld be ! means ( utiliz+ ! va/ /ores ( heat t lie 9 all ! sub/ances ar\nd u1 & conv]t+ !m into "w4 ,! "w w\ld no d\bt1 by means ( friction & o!rwise1 be ultimately reconv]t$ into heat2 b if ! process be rev]sible1 ! heat c\ld aga9 be conv]t$ into "w1 & s on = ev]4 ,b ! irrev]sibility ( ! process puts a /op to all ?is4 ,9 fact1 ,i may conv9ce myself by rubb+ a metal button on a piece ( wood h[ easily "w c be conv]t$ into heat1 :ile ! m9d completely fails to sugge/ any me?od by :i* ?is heat c be reconv]t$ into "w4 ,n[1 if ?is process goes on1 & always 9 "o direction1 !re c be no d\bt ab\t ! issue4 ,! me*anical en]gy ( ! univ]se w be m & m trans=m$ into univ]sally diffus$ heat1 until ! univ]se w no long] be a fit abode = liv+ be+s4 ,! conclusion is a />tl+ "o1 &1 9 ord] to br+ x m vividly be=e our read]s1 let u n[ proce$ to acqua9t ourselves ) ! v>i\s =ms ( useful en]gy t are at pres5t at our disposal1 & at ! same "t endeav\r to trace ! ultimate s\rces ( ^! supplies4 ,natural ,en]gies & _! ,s\rces4 #aif4 ,( en]gy 9 repose we h ! foll[+ v>ieties3--7#a47 ,! en]gy ( fuel4 7#b47 ,t ( food4 7#c47 ,t ( a head ( wat]4 7#d47 ,t :i* may be d]iv$ f ! tides4 7#e47 ,! en]gy ( *emical sep>ation impli$ 9 native sulphur1 native iron1 c4 ,!n1 ) reg>d to en]gy 9 action1 we h ma9ly ! foll[+ v>ieties3-- 7#a47 ,! en]gy ( air 9 motion4 7#b47 ,t ( wat] 9 motion4 ,fuel4 #aig4 ,let u beg9 fir/ ) ! en]gy impli$ 9 fuel4 ,we c1 ( c\rse1 burn fuel1 or cause x to comb9e ) ! oxyg5 ( ! air2 & we are !reby provid$ ) l>ge quantities ( heat ( high temp]ature1 by means ( :i* we may n only w>m ourselves & cook our food1 b also drive our heat-eng9es1 us+ x1 9 fact1 z a s\rce ( me*anical p[]4 ,fuel is ( two v>ieties--wood & coal4 ,n[1 if we consid] ! orig9 ( ^! we %all see t !y are produc$ by ! sun's rays4 ,c]ta9 ( ^! rays1 z we h already rem>k$ 7,art4 #ahj71 decompose c>bonic acid 9 ! leaves ( plants1 sett+ free ! oxyg51 :ile ! c>bon is us$ = ! /ructure or wood ( ! plant4 ,n[1 ! en]gy ( ^! rays is sp5t 9 ?is process1 &1 inde$1 !re is n en\gh ( su* en]gy left to produce a good photographic impression ( ! leaf ( a plant1 because x is all sp5t 9 mak+ wood4 ,we ?us see t ! en]gy impli$ 9 wood is d]iv$ f ! sun's rays1 & ! same rem>k applies to coal4 ,inde$1 ! only diff]5ce betwe5 wood & coal is "o ( age3 wood be+ rec5tly turn$ out f ,nature's laboratory1 :ile ?\s&s ( ye>s h elaps$ s9ce coal =m$ ! leaves ( liv+ plants4 #aih4 ,we are1 !re=e1 p]fectly ju/ifi$ 9 say+ t ! en]gy ( fuel is d]iv$ f ! sun's rays2#g coal be+ ! /ore :i* ,nature has laid up z a species ( capital = u1 :ile wood is our prec>i\s ye>ly income4 ,we are ?us at pres5t v mu* 9 ! position ( a "y heir1 :o has only rec5tly come into 8 e/ate1 & :o1 n cont5t ) ! income1 is rapidly squ&]+ 8 realiz$ prop]ty4 ,?is subject has be5 =cibly br\ght be=e u by ,pr(essor ,jevons1 :o has rem>k$ t n only are we sp5d+ our capital1 b we are sp5d+ ! mo/ available & valuable "p ( x4 ,= we are n[ us+ ! surface coal2 b a "t w come :5 ?is w be exhau/$1 & we %all be compell$ to g deep d[n = our supplies4 ,n[1 reg>d$ z a s\rce ( en]gy1 su* supplies1 if f> d[n1 w be less effective1 = we h to d$uct ! am\nt ( en]gy requisite 9 ord] to br+ !m to ! surface4 ,! result is t we mu/ contemplate a "t1 h[ev] f> di/ant1 :5 our supplies ( coal w be exhau/$1 & we %all be compell$ to resort to o!r s\rces ( en]gy4 ,food4 #aii4 ,! en]gy ( food is analog\s to t ( fuel1 & s]ves simil> purposes4 ,= j z fuel may be us$ ei!r = produc+ heat or = do+ "w1 s food has a tw(old (fice to p]=m4 ,9 ! fir/ place1 by its gradual oxidation1 x keeps up ! temp]ature ( ! body2 & 9 ! next place x is us$ z a s\rce ( en]gy1 on :i* to draw = ! p]=mance ( "w4 ,?us a man or a horse t works a great deal requires to eat m food ?an if he does n "w at all4 ,?us1 also1 a prison] condemn$ to h>d lab\r requires a bett] diet ?an "o :o does n "w1 & a soldi] dur+ ! fatigues ( w> f9ds x necess>y to eat m ?an dur+ a "t ( peace4 ,our food may be ei!r ( animal or vegetable orig9--if x be ! latt]1 x is imm$iately d]iv$1 l fuel1 f ! en]gy ( ! sun's rays2 b if x be ! =m]1 ! only diff]5ce is t x has pass$ ?r\gh ! body ( an animal be=e com+ to u3 ! animal has eat5 grass1 & we h eat5 ! animal4 ,9 fact1 we make use ( ! animal n only z a v>iety ( nutriti\s food1 b also to enable u indirectly to utilize ^? vegetable products1 su* z grasses1 :i* we c\ld n make use ( directly ) our pres5t dige/ive organs4 ,head ( ,wat]4 #bjj4 ,! en]gy ( a head ( wat]1 l t ( fuel & food1 is br\ght ab\t by ! sun's rays4 ,= ! sun vaporizes ! wat]1 :i*1 cond5s$ aga9 9 upl& di/ricts1 becomes available z a head ( wat]4 ,!re is1 h[ev]1 ! diff]5ce t fuel & food are due to ! act9ic p[] ( ! sun's rays1 :ile ! evaporation & cond5sation ( wat] are caus$ r by _! heat+ effect4 ,tidal ,en]gy4 #bja4 ,! en]gy d]iv$ f ! tides has1 h[ev]1 a diff]5t orig94 ,9 ,art4 #acc we h endeav\r$ to %[ h[ ! moon acts ^u ! fluid portions ( our globe1 ! result ( ?is action be+ a v gradual /oppage ( ! en]gy ( rotation ( ! e>?4 ,x is1 !re=e1 to ?is motion ( rotation t we mu/ look z ! orig9 ( any available en]gy d]iv$ f tidal mills4 ,native ,sulphur1 c4 #bjb4 ,! la/ v>iety ( available en]gy ( position 9 our li/ is t impli$ 9 native sulphur1 native iron1 c4 ,x has be5 rem>k$ by ,pr(essor ,tait1 to :om ?is me?od ( review+ our =ces is due1 t ?is may be ! primeval =m ( en]gy1 & t ! int]ior ( ! e>? may1 z f> z we "k1 be :olly compos$ ( matt] 9 its uncomb9$ =m4 ,z a s\rce ( available en]gy x is1 h[ev]1 ( no practical importance4 ,air & ,wat] 9 ,motion4 #bjc4 ,we proce$ next to ^? v>ieties ( available en]gy :i* repres5t motion1 ! *ief ( :i* are air 9 motion & wat] 9 motion4 ,x is ow+ to ! =m] t ! m>9] spreads 8 sail1 & c>ries 8 vessel f "o "p ( ! e>?'s surface to ano!r1 & x is likewise ow+ to ! same influ5ce t ! w9dmill gr9ds our corn4 ,aga91 wat] 9 motion is us$ p]haps ev5 m frequ5tly ?an air 9 motion z a s\rce ( motive p[]4 ,bo? ^! v>ieties ( en]gy are due )\t d\bt to ! heat+ effect ( ! sun's rays4 ,we may1 !re=e1 affirm t ) ! exception ( ! totally insignificant supply ( native sulphur1 c41 & ! small numb] ( tidal mills :i* may be 9 op]ation1 all our available en]gy is due to ! sun4 ,! ,sun--a ,s\rce ( ,high ,temp]ature ,heat4 #bjd4 ,let u1 !re=e1 n[ = a mom5t direct our att5tion to t mo/ wond]ful s\rce ( en]gy1 ! ,sun4 ,we h "h a va/ res]voir ( high temp]ature heat2 n[1 ?is is a k9d ( sup]ior en]gy :i* has always be5 9 mu* reque/4 ,numb]less attempts h be5 made to con/ruct a p]petual light1 j z simil> attempts h be5 made to con/ruct a p]petual motion1 ) ?is diff]5ce1 t a p]petual light 0 suppos$ to result f magical p[]s1 :ile a p]petual motion 0 attribut$ to me*anical skill4 ,sir ,walt] ,scott alludes to ?is belief 9 8 description ( ! grave ( ,mi*ael ,scott1 :i* is made to conta9 a p]petual light4 ,?us ! ,monk :o buri$ ! wiz>d tells ,william ( ,delora9e-- 8,lo1 ,w>rior6 n[ ! ,cross ( ,r$ ,po9ts to ! ,grave ( ! mighty dead2 ,)9 x burns a wondr\s light1 ,to *ase ! spirits t love ! night4 ,t lamp %all burn unqu5*ably ,until ! et]nal doom %all be40 ,& aga91 :5 ! tomb 0 op5$1 we read-- 8,i w\ld y _h be5 !re to see ,h[ ! light broke =? s glori\sly1 ,/ream'd upw>d to ! *ancel ro(1 ,& ?r\gh ! gall]ies f> alo(6 ,no e>?ly flame blaz$ e'er s bright40 ,no e>?ly flame--!re ! poet 0 "r--c]ta9ly n ( ?is e>?1 :]e light & all o!r =ms ( sup]ior en]gy are ess5tially evanesc5t4 ,a ,p]petual ,light ,impossible4 #bje4 ,9 tru?1 our read]s w at once p]ceive t a p]petual light is only ano!r "n = a p]petual motion1 because we c always d]ive visible en]gy out ( high temp]ature heat--inde$1 we d s e day 9 our /eam eng9es4 ,:51 !re=e1 we burn coal1 & cause x to comb9e ) ! oxyg5 ( ! air1 we d]ive f ! process a l>ge am\nt ( high temp]ature heat4 ,b is x n possible1 our read]s may ask1 to take ! c>bonic acid :i* results f ! combu/ion1 & by means ( l[ temp]ature heat1 ( :i* we h always abundance at our disposal1 *ange x back aga9 into c>bon & oxyg58 ,all ?is w\ld be possible if :at may be t]m$ ! temp]ature ( disassociation--t is to say1 ! temp]ature at :i* c>bonic acid sep>ates into its con/itu5ts--7 a l[ temp]ature1 & x w\ld also be possible if rays f a s\rce ( l[ temp]ature possess$ suffici5t act9ic p[] to decompose c>bonic acid4 ,b nei!r ( ^! is ! case4 ,nature w n be caught 9 a trap ( ?is k9d4 ,z if = ! v purpose ( /opp+ all su* speculations1 ! temp]atures ( disassociation = su* sub/ances z c>bonic acid are v high1 & ! act9ic rays capable ( caus+ _! decomposition belong only to s\rces ( exce$+ly high temp]ature1 su* z ! sun4#h ,is ! ,sun an ,exception8 #bjf4 ,we may1 !re=e1 take x = grant$ t a p]petual light1 l a p]petual motion1 is an impossibility2 & we h !n to inquire if ! same argum5t applies to our sun1 or if an exception is to be made 9 8 fav\r4 ,does ! sun /& ^u a foot+ ( 8 own1 or is x m]ely a "q ( "t ) him1 z ) all o!r in/ances ( high temp]ature heat8 ,be=e attempt+ to answ] ?is "q let u inquire into ! probable orig9 ( ! sun's heat4 ,orig9 ( ! ,sun's ,heat4 #bjg4 ,n[1 "s might be dispos$ to cut ! ,gordian knot ( su* an inquiry by ass]t+ t our lum9>y 0 at fir/ creat$ hot2 yet ! sci5tific m9d f9ds itself dis9cl9$ to repose ^u su* an ass]tion4 ,we pick up a r\nd pebble f ! bea*1 & at once ackn[l$ge !re has be5 "s physical cause = ! %ape into :i* x has be5 worn4 ,& s ) reg>d to ! heat ( ! sun1 we mu/ ask ourselves if !re be n "s cause n :olly imag9>y1 b "o :i* we "k1 or at lea/ suspect1 to be p]haps /ill 9 op]ation1 :i* c acc\nt = ! heat ( ! sun4 ,n[1 "h x is m easy to %[ :at _c acc\nt = ! sun's heat ?an :at c d s4 ,we may1 = in/ance1 be p]fectly c]ta9 t x _c h be5 caus$ by *emical action4 ,! mo/ probable !ory is t :i* 0 fir/ work$ out by ,helmholtz & ,?omson2#i & :i* attributes ! heat ( ! sun to ! primeval en]gy ( position possess$ by its p>ticles4 ,9 o!r words1 x is suppos$ t ^! p>ticles orig9ally exi/$ at a great di/ance f ea* o!r1 & t1 be+ end[$ ) ! =ce ( gravitation1 !y h s9ce gradually come toge!r1 :ile 9 ?is process heat has be5 g5]at$ j z x w\ld be if a /one 7 dropp$ f ! top ( a cliff t[>ds ! e>?4 #bjh4 ,nor is ?is case :olly imag9>y1 b we h "s reason = ?9k+ t x may /ill be 9 op]ation 9 ! case ( c]ta9 nebul :i*1 bo? 9 _! con/itution z reveal$ by ! spectroscope1 & 9 _! g5]al appe>ance1 impress ! behold] ) ! idea t !y are n yet fully cond5s$ into _! ultimate %ape & size4 ,if we all[ t by ?is means our lum9>y has obta9$ 8 wond]ful /ore ( high-class en]gy1 we h yet to inquire to :at ext5t ?is op]ation is go+ on at ! pres5t mom5t4 ,is x only a ?+ ( ! pa/1 or is x a ?+ also ( ! pres5t8 ,i ?9k we may reply t ! sun _c be cond5s+ v fa/1 at lea/1 )9 hi/orical times4 ,= if ! sun 7 s5sibly l>g] ?an at pres5t 8 total eclipse by ! moon w\ld be impossible4 ,n[1 su* eclipses h tak5 place1 at any rate1 = sev]al ?\s&s ( ye>s4 ,d\btless a small army ( meteors may be fall+ into our lum9>y1 :i* w\ld by ?is fall t5d to augm5t 8 heat2 yet ! supply d]iv$ f ?is s\rce mu/ surely be insignificant4 ,b if ! sun be n at pres5t cond5s+ s fa/ z to d]ive any suffici5t heat f ?is process1 & if 8 en]gy be v sp>+ly recruit$ f )\t1 x necess>ily foll[s t he is 9 ! position ( a man ^: exp5diture exce$s 8 income4 ,he is liv+ ^u 8 capital1 & is de/9$ to %>e ! fate ( all :o act 9 a simil> mann]4 ,we mu/1 !re=e1 contemplate a future p]iod :5 he w be poor] 9 en]gy ?an he is at pres5t1 & a p]iod /ill fur!r 9 ! future :5 he w altoge!r cease to %9e4 ,probable ,fate ( ! ,univ]se4 #bji4 ,if ?is be ! fate ( ! high temp]ature en]gy ( ! univ]se1 let u ?9k = a mom5t :at w happ5 to its visible en]gy4 ,we h spok5 already ab\t a m$ium p]vad+ space1 ! (fice ( :i* appe>s to be to degrade & ultimately ext+ui% all diff]5tial motion1 j z x t5ds to r$uce & ultimately equalize all diff]5ce ( temp]ature4 ,?us ! univ]se w\ld ultimately become an equally heat$ mass1 utt]ly wor?less z f> z ! production ( "w is conc]n$1 s9ce su* production dep5ds ^u diff]5ce ( temp]ature4 ,al?\gh1 !re=e1 9 a /rictly me*anical s5se1 !re is a cons]vation ( en]gy1 yet1 z reg>ds usefulness or fitness = liv+ be+s1 ! en]gy ( ! univ]se is 9 process ( det]ioration4 ,univ]sally diffus$ heat =ms :at we may call ! great wa/e-heap ( ! univ]se1 & ?is is gr[+ l>g] ye> by ye>4 ,at pres5t x does n s5sibly obtrude itself1 b :o kn[s t ! "t may n arrive :5 we %all be practically consci\s ( its gr[+ bigness8 #baj4 ,x w be se5 t 9 ?is *apt] we h reg>d$ ! univ]se1 n z a collection ( matt]1 b r z an en]getic ag5t--9 fact1 z a lamp4 ,n[1 x has be5 well po9t$ out by ,?omson1 t look$ at 9 ?is light1 ! univ]se is a sy/em t _h a beg9n+ & mu/ h an end2 = a process ( degradation _c be et]nal4 ,if we c\ld view ! univ]se z a c&le n lit1 !n x is p]haps conceivable to reg>d x z hav+ be5 always 9 exi/5ce2 b if we reg>d x r z a c&le t has be5 lit1 we become absolutely c]ta9 t x _c h be5 burn+ f et]nity1 & t a "t w come :5 x w cease to burn4 ,we are l$ to look to a beg9n+ 9 :i* ! p>ticles ( matt] 7 9 a diffuse *aotic /ate1 b end[$ ) ! p[] ( gravitation1 & we are l$ to look to an end 9 :i* ! :ole univ]se w be "o equally heat$ in]t mass1 & f :i* ev]y?+ l life or motion or beauty w h utt]ly gone away4 ,,footnotes3 #g ,?is fact seems to h be5 kn[n at a comp>atively e>ly p]iod to ,h]s*el & ! eld] ,/eph5son4 #h ,?is rem>k is due to ,sir ,william ,?omson4 #i ,may] & ,wat]/on seem fir/ to h caught ! rudim5ts ( ?is idea4 ,,*apt] ,,vi4 ,,! ,,position ,,( ,,life4 #baa4 ,we h hi!rto conf9$ ourselves almo/ entirely to a discussion ( ! laws ( en]gy1 z ^! affect inanimate matt]1 & h tak5 little or no acc\nt ( ! position ( life4 ,we h be5 cont5t v mu* to rema9 spectators ( ! conte/1 app>5tly =getful t we are at all conc]n$ 9 ! issue4 ,b ! conflict is n "o :i* admits ( on-look]s1--x is a univ]sal conflict 9 :i* we mu/ all take our %>e4 ,x may n1 !re=e1 be amiss if we endeav\r to asc]ta91 z well z we c1 our true position4 ,tw(old nature ( ,equilibrium4 #bab4 ,"o ( our e>lie/ me*anical lessons is on ! tw(old nature ( equilibrium4 ,we are told t ?is may be ( two k9ds1 /able & un/able1 & a v good illu/ration ( ^! two k9ds is furni%$ by an egg4 ,let u take a smoo? level table1 & place an egg ^u x2 we all "k 9 :at mann] ! egg w lie on ! table4 ,x w rema9 at re/1 t is to say1 x w be 9 equilibrium2 & n only s1 b x w be 9 /able equilibrium4 ,to prove ?is1 let u try to displace x ) our f+]1 & we %all f9d t :5 we remove ! pressure ! egg w spe$ily return to its previ\s position1 & w come to re/ aft] "o or two oscillations4 ,fur!rmore1 x has requir$ a s5sible exp5diture ( en]gy to displace ! egg4 ,all ?is we express by say+ t ! egg is 9 /able equilibrium4 ,me*anical ,in/ability4 #bac4 ,& n[ let u try to balance ! egg ^u its long] axis4 ,probably1 a suffici5t am\nt ( c>e w enable u to a*ieve ?is also4 ,b ! op]ation is a difficult "o1 & requires great delicacy ( t\*1 & ev5 aft] we h succe$$ we d n "k h[ long our success may la/4 ,! slighte/ impulse f )\t1 ! m]e/ brea? ( air1 may be suffici5t to ov]turn ! egg1 :i* is n[ mo/ evid5tly 9 un/able equilibrium4 ,if ! egg be ?us balanc$ at ! v edge ( ! table1 x is q probable t 9 a few m9utes x may topple ov] ^u ! floor2 x is :at we may call an ev5 *ance :e!r x w d s1 or m]ely fall ^u ! table4 ,n t m]e *ance has any?+ to d ) x1 or t its movem5ts are )\t a cause1 b we mean t its movem5ts are decid$ by "s ext]nal impulse s exce$+ly small z to be utt]ly beyond our p[]s ( obs]vation4 ,9 fact1 be=e mak+ ! trial we h c>efully remov$ ev]y?+ l a curr5t ( air1 or want ( level1 or ext]nal impulse ( any k9d1 s t :5 ! egg falls we are completely unable to assign ! orig9 ( ! impulse t has caus$ x to d s4 #bad4 ,n[1 if ! egg happ5s to fall ov] ! table ^u ! floor1 !re is a some:at consid]able transmutation ( en]gy2 = ! en]gy ( position ( ! egg1 due to ! height :i* x occupi$ on ! table1 has all at once be5 *ang$ into en]gy ( motion1 9 ! fir/ place1 & into heat 9 ! second1 :5 ! egg comes into contact ) ! floor4 ,if1 h[ev]1 ! egg happ5s to fall ^u ! table1 ! transmutation ( en]gy is comp>atively small4 ,x ?us appe>s t x dep5ds ^u "s ext]nal impulse1 s inf9itesimally small z to elude our obs]vation1 :e!r ! egg %all fall ^u ! floor & give rise to a comp>atively l>ge transmutation ( en]gy1 or :e!r x %all fall ^u ! table & give rise to a transmutation comp>atively small4 ,*emical ,in/ability4 #bae4 ,we ?us see t a body1 or sy/em1 9 un/able equilibrium may become subject to a v consid]able transmutation ( en]gy1 aris+ out ( a v small cause1 or antec$5t4 ,9 ! case n[ m5tion$1 ! =ce is t ( gravitation1 ! arrangem5t be+ "o ( visible me*anical in/ability4 ,b we may h a sub/ance1 or sy/em1 9 :i* ! =ce at "w is n gravity1 b *emical aff9ity1 & ! sub/ance1 or sy/em1 may1 "u c]ta9 peculi> conditions1 become *emically un/able4 ,:5 a sub/ance is *emically un/able1 x means t ! slighte/ impulse ( any k9d may det]m9e a *emical *ange1 j z 9 ! case ( ! egg ! slighte/ impulse f )\t occasion$ a me*anical displacem5t4 ,9 f9e1 a sub/ance1 or sy/em1 *emically un/able be>s a relation to *emical aff9ity some:at simil> to t :i* a me*anically un/able sy/em be>s to gravity4 ,gunp[d] is a famili> in/ance ( a *emically un/able sub/ance4 ,"h ! slighte/ sp>k may prove ! precursor ( a sudd5 *emical *ange1 accompani$ by ! in/antane\s & viol5t g5]ation ( a va/ volume ( heat$ gas4 ,! v>i\s explosive comp\nds1 su* z gun-cotton1 nitro-glyc]9e1 ! fulm9ates1 & _m m1 are all in/ances ( /ructures :i* are *emically un/able4 ,ma*9es are ( two k9ds4 #baf4 ,:5 we speak ( a /ructure1 or a ma*9e1 or a sy/em1 we simply mean a numb] ( individual p>ticles associat$ toge!r 9 produc+ "s def9ite result4 ,?us1 ! sol> sy/em1 a timepiece1 a rifle1 are examples ( inanimate ma*9es2 :ile an animal1 a human be+1 an army1 are examples ( animat$ /ructures or ma*9es4 ,n[1 su* ma*9es or /ructures are ( two k9ds1 :i* diff] f "o ano!r n only 9 ! object s\ght1 b also 9 ! means ( atta9+ t object4 #bag4 ,9 ! fir/ place1 we h /ructures or ma*9es 9 :i* sy/ematic action is ! object aim$ at1 & 9 :i* all ! arrangem5ts are ( a cons]vative nature1 ! elem5t ( in/ability be+ avoid$ z mu* z possible4 ,! sol> sy/em1 a timepiece1 a /eam-eng9e at "w1 are examples ( su* ma*9es1 & ! *>act]i/ic ( all su* is _! calculability4 ,?us ! skill$ a/ronom] c tell1 ) ! utmo/ precision1 9 :at place ! moon or ! planet ,v5us w be f\nd ?is "t next ye>4 ,or aga91 ! excell5ce ( a timepiece consi/s 9 its v>i\s h&s po9t+ accurately 9 a c]ta9 direction aft] a c]ta9 int]val ( "t4 ,9 l mann] we may safely c\nt ^u a /eam%ip mak+ s _m knots an h\r1 at lea/ :ile ! outw>d conditions rema9 ! same4 ,9 all ^! cases we make our calculations1 & we are n deceiv$--! end s\ght is regul>ity ( action1 & ! means employ$ is a /able arrangem5t ( ! =ces ( nature4 #bah4 ,n[1 ! *>act]i/ics ( ! o!r class ( ma*9es are precisely ! rev]se4 ,"h ! object aim$ at is n a regul>1 b a sudd5 & viol5t transmutation ( en]gy1 :ile ! means employ$ are un/able arrangem5ts ( natural =ces4 ,a rifle at full cock1 ) a delicate hair-trigg]1 is a v good in/ance ( su* a ma*9e1 :]e ! slighte/ t\* f )\t may br+ ab\t ! explosion ( ! gunp[d]1 & ! propulsion ( ! ball ) a v great velocity4 ,n[1 su* ma*9es are em95tly *>act]iz$ by _! incalculability4 #bai4 ,to make our mean+ cle>1 let u suppose t two sportsm5 g out hunt+ toge!r1 ea* ) a good rifle & a good pocket *ronomet]4 ,aft] a h>d day's "w1 ! "o turns to 8 companion & says3--8,x is n[ six o'clock by my wat*2 we _h bett] re/ ourselves10 ^u :i* ! o!r looks at 8 wat*1 & he w\ld be v mu* surpris$ & exce$+ly indignant ) ! mak]1 if he did n f9d x six o'clock also4 ,_! *ronomet]s are evid5tly 9 ! same /ate1 & h be5 do+ ! same ?+2 b :at ab\t _! rifles8 ,giv5 ! condition ( ! "o rifle1 is x possible by any ref9em5t ( calculation to d$uce t ( ! o!r8 ,we feel at once t ! b>e supposition is ridicul\s4 #bbj4 ,x is ?us app>5t t1 z reg>ds en]gy1 /ructures are ( two k9ds4 ,9 "o ( ^!1 ! object s\ght is regul>ity ( action1 & ! means employ$1 a /able arrangem5t ( natural =ces3 :ile 9 ! o!r1 ! end s\ght is fre$om ( action1 & a sudd5 transmutation ( en]gy1 ! means employ$ be+ an un/able arrangem5t ( natural =ces4 ,! "o set ( ma*9es are *>act]iz$ by _! calculability--! o!r by _! incalculability4 ,! "o set1 :5 at "w1 are n easily put wrong1 :ile ! o!r set are *>act]iz$ by great delicacy ( con/ruction4 ,an ,animal is a delicately-con/ruct$ ,ma*9e4 #bba4 ,b p]haps ! read] may object to our use ( ! rifle z an illu/ration4 ,= al?\gh x is und\bt$ly a delicately-con/ruct$ ma*9e1 yet a rifle does n repres5t ! same surpass+ delicacy z t1 = in/ance1 :i* *>act]izes an egg balanc$ on its long] axis4 ,ev5 if at full cock1 & ) a hair trigg]1 we may be p]fectly c]ta9 x w n g (f ( its own accord4 ,al?\gh its object is to produce a sudd5 & viol5t transmutation ( en]gy1 yet ?is requires to be prec$$ by ! application ( an am\nt ( en]gy1 h[ev] small1 to ! trigg]1 & if ?is be n sp5t ^u ! rifle1 x w n g (f4 ,!re is1 no d\bt1 delicacy ( con/ruction1 b ?is has n ris5 to ! height ( incalculability1 & x is only :5 9 ! h&s ( ! sportsman t x becomes a ma*9e ^u ! condition ( :i* we _c calculate4 ,n[1 9 mak+ ?is rem>k1 we def9e ! position ( ! sportsman himself 9 ! ,univ]se ( ,en]gy4 ,! rifle is delicately con/ruct$1 b n surpass+ly s2 b sportsman & rifle1 toge!r1 =m a ma*9e ( surpass+ delicacy1 ergo ! sportsman himself is su* a ma*9e4 ,we ?us beg9 to p]ceive t a human be+1 or inde$ an animal ( any k9d1 is 9 tru? a ma*9e ( a delicacy t is practically inf9ite1 ! condition or motions ( :i* we are utt]ly unable to pr$ict4 ,9 tru?1 is !re n a transp>5t absurdity 9 ! v ?\ght t a man may become able to calculate 8 own movem5ts1 or ev5 ^? ( 8 fell[8 ,life is l ! ,comm&] ( an ,army4 #bbb4 ,let u n[ introduce ano!r analogy--let u suppose t a w> is be+ c>ri$ on by a va/ army1 at ! head ( :i* !re is a v great comm&]4 ,n[1 ?is comm&] kn[s too well to expose 8 p]son2 9 tru?1 he is nev] se5 by any ( 8 subord9ates4 ,he rema9s at "w 9 a well-gu>d$ room1 f :i* telegraphic wires lead to ! headqu>t]s ( ! v>i\s divisions4 ,he c ?us1 by means ( ^! wires1 transmit 8 ord]s to ! g5]als ( ^! divisions1 & by ! same means receive back in=mation z to ! condition ( ea*4 ,?us 8 headqu>t]s become a c5tre1 into :i* all in=mation is p\r$1 & out ( :i* all comm&s are issu$4 ,n[1 t my/]i\s ?+ call$ life1 ab\t ! nature ( :i* we "k s little1 is probably n unlike su* a comm&]4 ,life is n a bully1 :o swagg]s out into ! op5 univ]se1 upsett+ ! laws ( en]gy 9 all directions1 b r a consummate /rategi/1 :o1 sitt+ 9 8 secret *amb]1 be=e 8 wires1 directs ! movem5ts ( a great army4#aj #bbc4 ,let u next suppose t our imag9>y army is 9 rapid m>*1 & let u try to f9d out ! cause ( ?is movem5t4 ,we f9d t1 9 ! fir/ place1 ord]s to m>* h be5 issu$ to ! troops "u !m by ! comm&]s ( ea* regim5t4 ,9 ! next place1 we le>n t /aff (fic]s1 atta*$ to ! g5]als ( ! v>i\s divisions1 h convey$ ^! ord]s to ! regim5tal comm&]s2 &1 f9ally1 we le>n t ! ord] to m>* has be5 telegraph$ f headqu>t]s to ^! v>i\s g5]als4 ,desc5d+ n[ to ourselves1 x is probably some:]e 9 ! my/]i\s & well-gu>d$ bra9-*amb] t ! delicate directive t\* is giv5 :i* det]m9es our movem5ts4 ,?is *amb] =ms1 z x 71 ! headqu>t]s ( ! g5]al 9 comm&1 :o is s well )drawn z to be absolutely invisible to all 8 subord9ates4 #bbd4 ,j\le1 ,c>p5t]1 & ,may] 7 at an e>ly p]iod aw>e ( ! re/rictions "u :i* animals are plac$ by ! laws ( en]gy1 & 9 virtue ( :i* ! p[] ( an animal1 z f> z en]gy is conc]n$1 is n creative1 b only directive4 ,x 0 se5 t1 9 ord] to d "w1 an animal mu/ be f$2 &1 ev5 at a /ill e>li] p]iod1 ,c\nt ,rum=d rem>k$ t a ton ( hay w be adm9i/]$ m economically by fe$+ a horse ) x1 & !n gett+ "w out ( ! horse1 ?an by burn+ x z fuel 9 an eng9e4 #bbe4 ,9 ?is *apt]1 ! same l9e ( ?\ght has be5 c>ri$ out a little fur!r4 ,we h se5 t life is associat$ ) delicately-con/ruct$ ma*9es1 s t :5ev] a transmutation ( en]gy is br\ght ab\t by a liv+ be+1 c\ld we trace ! ev5t back1 we %\ld f9d t ! physical antec$5t 0 probably a mu* less transmutation1 :ile aga9 ! antec$5t ( ?is w\ld probably be f\nd /ill less1 & s on1 z f> z we c\ld trace x4 #bbf4 ,b ) all ?is1 we d n pret5d to h discov]$ ! true nature ( life itself1 or ev5 ! true nature ( its relation to ! mat]ial univ]se4 ,:at we h v5tur$ is ! ass]tion t1 z f> z we c judge1 life is always associat$ ) ma*9]y ( a c]ta9 k9d1 9 virtue ( :i* an extremely delicate directive t\* is ultimately magnifi$ into a v consid]able transmutation ( en]gy4 ,inde$1 we c h>dly imag9e ! fre$om ( motion impli$ 9 life to exi/ ap>t f ma*9]y possess$ ( v great delicacy ( con/ruction4 ,9 f9e1 we h n succe$$ 9 solv+ ! problem z to ! true nature ( life1 b h only driv5 ! difficulty into a bord]l& ( ?ick d>kness1 into :i* ! light ( k has n yet be5 able to p5etrate4 ,organiz$ ,tissues are subject to ,decay4 #bbg4 ,we h ?us le>n$ two ?+s1 =1 9 ! fir/ place1 we h le>n$ t life is associat$ ) delicacy ( con/ruction1 & 9 ! next 7,art4 #bbj71 t delicacy ( con/ruction implies an un/able arrangem5t ( natural =ces4 ,we h n[ to rem>k t ! p>ticul> =ce :i* is ?us us$ by liv+ be+s is *emical aff9ity4 ,our bodies are1 9 tru?1 examples ( an un/able arrangem5t ( *emical =ces1 & ! mat]ials :i* compos$ !m1 if n liable to sudd5 explosion1 l fulm9at+ p[d]1 are yet preem95tly ! subjects ( decay4 #bbh4 ,n[1 ?is is m ?an a m]e g5]al /atem5t2 x is a tru? t admits ( degrees1 & 9 virtue ( :i* ^? p>ts ( our bodies :i* h1 dur+ life1 ! noble/ & mo/ delicate (fice to p]=m1 are ! v fir/ to p]i% :5 life is ext9ct4 8,oh6 o'er ! eye dea? mo/ ex]ts 8 might1 ,& hurls ! _s f h] ?rone ( light2 ,s9ks ^? blue orbs 9 _! long la/ eclipse1 ,b sp>es u yet ! *>m ar\nd ! lips40 ,s speaks ! poet1 & we h "h an aspect ( ?+s 9 :i* ! lam5t ( ! poet becomes ! true int]pretation ( nature4 ,diff]5ce betwe5 ,animals & ,inanimate ,ma*9es4 #bbi4 ,we are n[ able to recognize ! diff]5ce betwe5 ! relations to en]gy ( a liv+ be+1 su* z man1 & a ma*9e1 su* z a /eam-eng9e4 ,!re are _m po9ts 9 common betwe5 ! two4 ,bo? require to be f$1 & 9 bo? !re is ! transmutation ( ! en]gy ( *emical sep>ation impli$ 9 fuel & food into t ( heat & visible motion4 ,b :ile ! "o--! eng9e--requires = its ma9t5ance only c>bon1 or "s o!r v>iety ( *emical sep>ation1 ! o!r--! liv+ be+--dem&s to be suppli$ ) organiz$ tissue4 ,9 fact1 t delicacy ( con/ruction :i* is s ess5tial to our well-be+1 is n some?+ :i* we c elaborate int]nally 9 our own frames--all t we c d is to appropriate & assimilate t :i* comes to u f )\t2 x is already pres5t 9 ! food :i* we eat4 ,ultimate ,dep5d5ce ( ,life ^u ! ,sun4 #bcj4 ,we h already 7,art4 #bjc7 be5 l$ to recognize ! sun z ! ultimate mat]ial s\rce ( all ! en]gy :i* we possess1 & we mu/ n[ reg>d him z ! s\rce likewise ( all our delicacy ( con/ruction4 ,x requires ! en]gy ( 8 high temp]ature rays s to wield & manipulate ! p[]ful =ces ( *emical aff9ity2 s to balance ^! v>i\s =ces aga9/ ea* o!r1 z to produce 9 ! vegetable some?+ :i* w af=d our frames1 n only en]gy1 b also delicacy ( con/ruction4 ,l[ temp]ature heat w\ld be utt]ly unable to accompli% ?is2 x consi/s ( e!real vibrations :i* are n suffici5tly rapid1 & ( waves t are n suffici5tly %ort1 = ! purpose ( %ak+ asund] ! con/itu5ts ( comp\nd molecules4 #bca4 ,x ?us appe>s t animals are1 9 m ways ?an "o1 p5sion]s ^u ! sun's b\nty2 & ^? in/ances1 :i* at fir/ sight appe> to be exceptions1 w1 if /udi$ suffici5tly1 only s]ve to confirm ! rule4 ,?us ! rec5t rese>*es ( ,dr4 ,c>p5t] & ,pr(essor ,wyville ,?omson h disclos$ to u ! exi/5ce ( m9ute liv+ be+s 9 ! deepe/ p>ts ( ! ocean1 into :i* we may be almo/ sure no sol> ray c p5etrate4 ,h[1 !n1 d ^! m9ute creatures obta9 t en]gy & delicacy ( con/ruction )\t :i* !y _c live8 9 o!r words1 h[ are !y f$8 ,n[1 ! same naturali/s :o discov]$ ! exi/5ce ( ^! creatures1 h rec5tly furni%$ u ) a v probable explanation ( ! my/]y4 ,!y ?9k x highly probable t ! :ole ocean conta9s 9 x organic matt] to a v small b yet p]ceptible ext5t1 =m+1 z !y express x1 a sort ( dilut$ s\p1 :i* ?us becomes ! food ( ^! m9ute creatures4 #bcb4 ,9 conclusion1 we are dep5d5t ^u ! sun & c5tre ( our sy/em1 n only = ! m]e en]gy ( our frames1 b also = our delicacy ( con/ruction--! future ( our race dep5ds ^u ! sun's future4 ,b we h se5 t ! sun mu/ h _h a beg9n+1 & t he w h an end4 ,we are ?us induc$ to g5]alize /ill fur!r1 & reg>d1 n only our own sy/em1 b ! :ole mat]ial univ]se :5 view$ ) respect to s]viceable en]gy1 z ess5tially evanesc5t1 & z embrac+ a succession ( physical ev5ts :i* _c g on = ev] z !y are4 ,b "h at l5g? we come to matt]s beyond our grasp2 = physical sci5ce _c in=m u :at mu/ h be5 be=e ! beg9n+1 nor yet c x tell u :at w take place aft] ! end4 ,,footnotes3 #aj ,see an article on 8,! ,position ( ,life10 by ! au?or ( ?is "w1 9 conjunction ) ,mr4 ,j4 ,n4 ,locky]1 8,macmillan's ,magaz9e10 ,septemb]1 #ahfh2 also a lecture on 8,! ,rec5t ,developm5ts ( ,cosmical ,physics10 by ! au?or ( ?is "w4 ,,app5dix4 ,,correlation ,,( ,,vital ,,) ,,*emical ,,& ,,physical ,,=ces4 ,,by ,,joseph ,,le ,,conte1 ,,pr(essor ,,( ,,geology ,,& ,,natural ,,hi/ory ,,9 ,,! ,,univ]sity ,,( ,,cali=nia4 ,,correlation ,,( ,,vital ,,) ,,*emical ,,& ,,physical ,,=ces4 ,vital =ce2 :5ce is x d]iv$8 ,:at is its relation to ! o!r =ces ( ,nature8 ,! answ] ( mod]n sci5ce to ^! que/ions is3 ,x is d]iv$ f ! l[] =ces ( ,nature2 x is relat$ to o!r =ces mu* z ^! are relat$ to ea* o!r--x is correlat$ ) *emical & physical =ces4 ,at "o "t matt] 0 suppos$ to be de/ructible4 ,by combu/ion or by evaporation matt] seem$ to be consum$--to pass out ( exi/5ce2 b n[ we "k x only *anges its =m f ! solid or liquid to ! gase\s condition--f ! visible to ! invisible--& t1 amid all ^! *anges1 ! same quantity ( matt] rema9s4 ,creation or de/ruction ( matt]1 increase or dim9ution ( matt]1 lies beyond ! doma9 ( ,sci5ce2 h] doma9 is conf9$ entirely to ! *anges ( matt]4 ,n[1 x is ! doctr9e ( mod]n sci5ce t ! same is true ( =ce4 ,=ce seems (t5 to be annihilat$4 ,two cannon-balls ( equal size & velocity meet ea* o!r & fall motionless4 ,! imm5se en]gy ( ^! mov+ bodies seems to pass out ( exi/5ce4 ,b n s2 x is *ang$ into heat1 & ! exact am\nt ( heat may be calculat$2 moreov]1 an equal am\nt ( heat may be *ang$ back aga9 into an equal am\nt ( mom5tum4 ,"h1 !re=e1 =ce is n lo/1 b is *ang$ f a visible to an invisible =m4 ,motion is *ang$ f bodily motion into molecul> motion4 ,?us heat1 light1 electricity1 magnetism1 *emical aff9ity1 & me*anical =ce1 are transmutable into ea* o!r1 back & =?2 b1 amid all ^! *anges1 ! am\nt ( =ce rema9s un*ang$4 ,=ce is incapable ( de/ruction1 except by ! same p[] :i* creat$ x4 ,! doma9 ( ,sci5ce lies )9 ! limits ( ^! *anges--creation & annihilation lie outside ( h] doma94 ,! mutual conv]tibility ( =ces into ea* o!r is call$ correlation ( =ces2 ! p]si/5ce ( ! same am\nt1 amid all ^! protean =ms1 is call$ cons]vation ( =ce4#aa ,! correlation ( physical =ces ) ea* o!r & ) *emical =ce is n[ univ]sally ackn[l$g$ & some:at cle>ly conceiv$4 ,! correlation ( vital =ce ) ^! is n univ]sally ackn[l$g$1 &1 :]e ackn[l$g$1 is only imp]fectly conceiv$4 ,9 #ahei ,i publi%$ a pap]#ab 9 :i* ,i attempt$ to put ! idea ( correlation ( vital =ce ) *emical & physical =ces 9 a m def9ite & sci5tific =m4 ,! views express$ 9 t pap] h be5 g5]ally adopt$ by physiologi/s4 ,s9ce ! publication ( ! pap] ref]r$ to1 ! subject has la9 9 my m9d1 & gr[n at lea/ some:at4 ,i propose1 !re=e1 n[ to rembody my views 9 a m popul> =m1 ) su* additions z h occurr$ to me s9ce4 ,!re are f\r planes ( mat]ial exi/5ce1 :i* may be repres5t$ z rais$ "o above ano!r4 ,^! are3 #a4 ,! plane ( elem5t>y exi/5ce2 #b4 ,! plane ( *emical comp\nds1 or m9]al k+dom2 #c4 ,! plane ( vegetable exi/5ce2 &1 #d4 ,! plane ( animal exi/5ce4 ,_! relations to ea* o!r are truly express$ by writ+ !m "o above ! o!r1 ?us3 ,i may sometimes use ! ^w en]gy in/ead4 ,if any "o %\ld *>ge me ) want ( precision 9 language1 my answ] is3 ,our language _c be m precise until our ideas 9 ?is dep>tm5t are f> cle>] ?an n[4 #d4 ,animal ,k+dom4 #c4 ,vegetable ,k+dom4 #b4 ,m9]al ,k+dom4 #a4 ,elem5ts4 ,n[1 x is a rem>kable fact t !re is a special =ce1 ^: function x is to raise matt] f ea* plane to ! plane above1 & to execute movem5ts on ! latt]4 ,?us1 x is ! function ( *emical aff9ity alone to raise matt] f ,no4 #a to ,no4 #b1 z well z to execute all ! movem5ts1 back & =?1 by action & reaction2 9 a ^w1 to produce all ! ph5om5a on ,no4 #b :i* toge!r con/itute ! sci5ce ( *emi/ry4 ,x is ! pr]ogative ( vegetable life-=ce alone to lift matt] f ,no4 #b to ,no4 #c1 z well z to execute all ! movem5ts on t plane1 :i* toge!r con/itute ! sci5ce ( vegetable physiology4 ,x is ! pr]ogative ( animal life-=ce alone to lift matt] f ,no4 #c to ,no4 #d1 & to preside ov] ! movem5ts on ?is plane1 :i* toge!r con/itute ! sci5ce ( animal physiology4 ,b !re is no =ce 9 ,nature capable ( rais+ matt] at once f ,no4 #a to ,no4 #c1 or f ,no4 #b to ,no4 #d1 )\t /opp+ & receiv+ an accession ( =ce1 ( a diff]5t k9d1 on ! int]m$iate plane4 ,plants _c fe$ ^u elem5ts1 b only on *emical comp\nds2 animals _c fe$ on m9]als1 b only on vegetables4 ,we %all see 9 ! sequel t ?is is ! necess>y result ( ! pr9ciple ( cons]vation ( =ce 9 vital ph5om5a4 ,x is well kn[n t atoms1 9 a nasc5t /ate--i4 e41 at ! mom5t ( _! sep>ation f previ\s comb9ation--are end[$ ) peculi> & p[]ful aff9ity4 ,oxyg5 & nitrog51 nitrog5 & hydrog51 hydrog5 & c>bon1 :i* %[ no aff9ity = ea* o!r "u ord9>y circum/ances1 readily unite :5 "o or bo? are 9 a nasc5t condition4 ,! reason seems to be t1 :5 ! elem5ts ( a comp\nd are torn asund]1 ! *emical aff9ity :i* previ\sly b\nd !m toge!r is set free1 ready & eag] to unite ! nasc5t elem5ts ) :atev] !y come 9 contact )4 ,?is /ate ( exalt$ *emical en]gy is reta9$ b a little :ile1 because x is liable to be *ang$ into "s o!r =m ( =ce1 probably heat1 & is !re=e no long] *emical en]gy4 ,to illu/rate by ! planes3 matt] fall+ d[n f ,no4 #b to ,no4 #a g5]ates =ce by :i* matt] is lift$ f ,no4 #a to ,no4 #b4 ,decomposition g5]ates ! =ce by :i* comb9ation is effect$4 ,?is pr9ciple und]lies e ?+ ,i %all fur!r say4 ,!re are1 !re=e1 two ideas or pr9ciples und]ly+ ?is pap]3 #a4 ,! correlation ( vital ) physical & *emical =ces2 #b4 ,t 9 all cases vital =ce is produc$ by decomposition--is trans=m$ nasc5t aff9ity4 ,nei!r ( ^! is new4 ,grove1 _m ye>s ago1 br\ght out1 9 a vague mann]1 ! idea t vital =ce 0 correlat$ ) *emical & physical =ces4#ac ,9 #ahdh ,dr4 ,freke1 ,m4 ,r4 ,i4 ,a41 ( ,dubl91 fir/ advanc$ ! idea t vital =ce ( animal life 0 g5]at$ by decomposition4 ,9 #ahea ! same idea 0 br\ght out aga9 by ,dr4 ,watt]s1 ( ,/4 ,l\is4 ,^! pap]s 7 unkn[n to me :5 ,i wrote my article4 ,!y h be5 s5t to me 9 ! la/ few ye>s by _! respective au?ors4 ,nei!r ( ^! au?ors1 h[ev]1 ext5ds ?is pr9ciple to vegetation1 ! mo/ fundam5tal & mo/ important ph5om5on ( life4 ,9 #aheg ! same idea 0 aga9 br\ght out by ,pr(4 ,h5ry1 ( ! ,smi?sonian ,in/itution1 & by him ext5d$ to vegetation4 ,i d n1 !re=e1 n[ claim to h fir/ advanc$ ?is idea1 b ,i d claim to h 9 "s measure rescu$ x f vagu5ess1 & giv5 x a cle>] & m sci5tific =m4 ,i wi% n[ to apply ^! pr9ciples 9 ! explanation ( ! mo/ important ph5om5a ( vegetable & animal life3 #a4 ,,vegetation4--,! mo/ important ph5om5on 9 ! life-hi/ory ( a plant--9 fact1 ! />t+-po9t ( all life1 bo? vegetable & animal--is ! =mation ( organic matt] 9 ! leaves4 ,! necess>y conditions = ?is wond]ful *ange ( m9]al into organic matt] seem to be1 sunlight1 *lorophyl1 & liv+ protoplasm1 or bioplasm4 ,?is is ! ph5om5on ,i wi% n[ to discuss4 ,! pla/ic matt]s ( :i* vegetable /ructure is built are ( two k9ds--amyloids & album9oids4 ,! amyloids1 or />* & sug> gr\ps1 consi/ ( ,c1 ,h1 & ,o2 ! album9oids ( ,c1 ,h1 ,o1 ,n1 & a little ,s & ,p4 ,! quantity ( sulphur & phosphorus is v small1 & we w neglect !m 9 ?is discussion4 ,! food out ( :i* ^! sub/ances are elaborat$ are1 ,,co1 ,h,o1 & ,h#c,n--c>bonic acid1 wat]1 & ammonia4 ,n[1 by ! ag5cy ( sunlight 9 ! pres5ce ( *lorophyl & bioplasm1 ^! *emical comp\nds 7,,co1 ,h,o1 & ,h#c,n7 are torn asund]1 or %ak5 asund]1 or decompos$2 ! excess ( ,o1 or ( ,o & ,h1 is reject$1 & ! rema9+ elem5ts 9 a nasc5t condition comb9e to =m organic matt]4 ,to =m ! amyloids--/>*1 dextr9e1 sug>1 cellulose--only ,,co & ,h,o are decompos$1 & excess ( ,o reject$4 ,to =m album9oids1 or protoplasm1 ,,co1 ,h,o1 & ,h#c,n1 are decompos$1 & excess ( ,o & ,h reject$4 ,x w\ld seem 9 ?is case1 !re=e1 t physical =ce 7light7 is *ang$ into nasc5t *emical =ce1 & ?is nasc5t *emical =ce1 "u ! peculi> conditions pres5t1 =ms organic matt]1 & reappe>s z vital =ce4 ,light fall+ on liv+ gre5 leaves is de/roy$ or consum$ 9 do+ ! "w ( decomposition2 disappe>s z light1 to reappe> z nasc5t *emical en]gy2 & ?is 9 its turn disappe>s 9 =m+ organic matt]1 to reappe> z ! vital =ce ( ! organic matt] ?us =m$4 ,! light :i* disappe>s is proportion$ to ! ,o1 or ! ,o & ,h reject$2 is proportion$ also to ! quantity ( organic matt] =m$1 & also to ! am\nt ( vital =ce result+4 ,to illu/rate3 ,9 ! case ( amyloids1 oxyg5-excess fall+ or runn+ d[n f plane ,no4 #b to plane ,no4 #a g5]ates =ce to raise ,c1 ,h1 & ,o1 f plane ,no4 #b to plane ,no4 #c4 ,9 ! case ( album9oids1 oxyg5-excess & hydrog5-excess runn+ d[n f ,no4 #b to ,no4 #a g5]ate =ce to raise ,c1 ,h1 ,o1 & ,n1 f ,no4 #b to ,no4 #c4 ,to illu/rate aga93 ,z sun-heat fall+ ^u wat] disappe>s z heat1 to reappe> z me*anical p[]1 rais+ ! wat] into ! cl\ds1 s sunlight fall+ ^u gre5 leaves disappe>s z light1 to reappe> z vital =ce lift+ matt] f ! m9]al into ! organic k+dom4 #b4 ,,g]m9ation4--,gr[+ plants1 x is se51 take _! life-=ce f ! sun2 b se$s g]m9ate & comm5ce to gr[ 9 ! d>k4 ,evid5tly !re mu/ be "s o!r s\rce f :i* !y draw _! supply ( =ce4 ,!y _c draw =ce f ! sun4 ,?is fact is intimately connect$ ) ano!r fact1 viz41 t !y d n draw _! food f ! m9]al k+dom4 ,! se$ 9 g]m9ation fe$s entirely ^u a supply ( organic matt] laid up = x by ! "m-plant4 ,x is ! decomposition ( ?is organic matt] :i* supplies ! =ce ( g]m9ation4 ,*emical comp\nds are comp>atively /able--x requires sunlight to te> !m asund]2 b organic matt] is m easily decompos$--x is almo/ spontane\sly decompos$4 ,x may be t heat 7a necess>y condition ( g]m9ation7 is ! =ce :i* det]m9es ! decomposition4 ,h[ev] ?is may be1 x is c]ta9 t a portion ( ! organic matt] laid up 9 ! se$ is decompos$1 burn$ up1 to =m ,,co & ,h,o1 & t ?is combu/ion furni%es ! =ce by :i* ! mason-"w ( tissue-mak+ is accompli%$4 ,9 o!r words1 ( ! food laid up 9 ! =m ( />*1 dextr9e1 protoplasm1 a portion is decompos$ to furni% ! =ce by :i* ! rema9d] is organiz$4 ,h5ce ! se$ always loses weight 9 g]m9ation2 x _c develop unless x is 9 "p consum$2 8x is n quick5$ except x die40 ,?is self-consumption cont9ues until ! leaves & roots are =m$2 !n x beg9s to draw =ce f ! sun1 & food f ! m9]al k+dom4 ,to illu/rate3 ,9 g]m9ation1 matt] runn+ d[n f plane ,no4 #c to plane ,no4 #b g5]ates =ce by :i* o!r simil> matt] is mov$ ab\t & rais$ to a some:at high] position on plane ,no4 #c4 ,z wat] rais$ by ! sun may be /or$ 9 res]voirs1 & 9 runn+ d[n f ^! may d "w1 s matt] rais$ by sun-=ce into ! organic k+dom by "o g5]ation is /or$ z =ce to d ! "w ( g]m9ation ( ! next g5]ation4 ,aga91 z1 9 wat] runn+ ?r\gh an hydraulic ram1 a portion runs to wa/e1 9 ord] to g5]ate =ce to lift ! rema9d] to a high] level1 s1 ( organic matt] /or$ 9 ! se$1 a portion runs to wa/e to create =ce to organize ! rema9d]4 ,?us1 !n1 x w be se5 t ?ree ?+s1 viz41 ! abs5ce ( sunlight1 ! use ( organic food1 & ! loss ( weight1 are indissolubly connect$ 9 g]m9ation1 & all expla9$ by ! pr9ciple ( cons]vation ( =ce4 #c4 ,,/>t+ ,,( ,,buds4--,decidu\s trees are entirely de/itute ( leaves dur+ ! w9t]4 ,! buds mu/ />t to gr[ 9 ! spr+ )\t leaves1 & !re=e )\t draw+ =ce f ! sun4 ,h5ce1 also1 food 9 ! organic =m mu/ be1 & is1 laid up f ! previ\s ye> 9 ! body ( ! tree4 ,a portion ( ?is is consum$ ) ! =mation ( ,,co & ,h,o1 9 ord] to create =ce = ! developm5t ( ! buds4 ,s soon z by ?is means ! leaves are =m$1 ! plant beg9s to draw =ce f ! sun1 & food f ! m9]al k+dom4 #d4 ,,pale ,,plants4--,fungi & etiolat$ plants h no *lorophyl1 !re=e _c draw _! =ce f ! sun1 nor make organic matt]s f inorganic4 ,h5ce ^! also mu/ fe$ on organic matt]2 n1 inde$1 on />*1 dextr9e1 & protoplasm1 b on decay+ organic matt]4 ,9 ^! plants ! organic matt] is tak5 up 9 "s =m int]m$iate betwe5 ! planes ,no4 #c & ,no4 #b4 ,! matt] ?us tak5 up is1 a portion ( x1 consum$ ) ! =mation ( ,,co & ,h,o1 9 ord] to create =ce necess>y to organize ! rema9d]4 ,to illu/rate3 ,matt] fall+ f "s int]m$iate po9t betwe5 ,no4 #b & ,no4 #c to ,no4 #b1 produces =ce suffici5t to raise matt] f ! same int]m$iate po9t to ,no4 #c2 a portion runs to wa/e d[nw>d1 & creates =ce to pu% ! rema9d] upw>d4 #e4 ,,gr[? ,,( ,,gre5 ,,plants ,,at ,,night4--,x is well kn[n t almo/ all plants gr[ at night z well z 9 ! day4 ,x is also kn[n t plants at night exhale ,,co4 ,^! two facts h n1 h[ev]1 z f> z ,i "k1 be5 connect$ ) "o ano!r1 & ) ! pr9ciple ( cons]vation ( =ce4 ,x is usually suppos$ t 9 ! night ! decomposition ( ,,co & exhalation ( oxyg5 are *eck$ by )drawal ( sun light1 & "s ( ! ,,co 9 ! asc5d+ sap is exhal$ by a physical law4 ,b ?is does n acc\nt = ! gr[?4 ,x is evid5t t1 9 ! abs5ce ( sun light1 ! =ce requir$ = ! "w ( tissue-build+ c be d]iv$ only f ! decomposition & combu/ion ( organic matt]4 ,!re are two views z to ! s\rce ( ?is organic matt]1 ei!r or bo? ( :i* may be correct3 ,fir/4 ,!re seems to be no d\bt t mo/ plants1 especially ^? gr[n 9 soils ri* 9 humus1 take up a portion ( _! food 9 ! =m ( semi-organic matt]1 or soluble humus4 ,! combu/ion ( a portion ( ?is 9 e "p ( ! plant1 by means ( oxyg5 also absorb$ by ! roots1 & ! =mation ( ,,co1 und\bt$ly creates a supply ( =ce night & day1 indep5d5tly ( sunlight4 ,! =ce ?us produc$ by ! combu/ion ( a portion might be us$ to raise ! rema9d] into />*1 dextr9e1 etc41 or might be us$ 9 tissue-build+4 ,dur+ ! day1 ! ,,co ?us produc$ w\ld be aga9 decompos$ 9 ! leaves by sunlight1 & ?us create an additional supply ( =ce4 ,dur+ ! night1 ! ,,co w\ld be exhal$4#ad ,aga93 ,x is possible t m organic matt] is made by sunlight dur+ ! day ?an is us$ up 9 tissue-build+4 ,"s ( ?is excess is aga9 consum$1 & =ms ,,co & ,h,o1 9 ord] to cont9ue ! tissue-build+ process dur+ ! night4 ,?us ! plant dur+ ! day /ores up sun-=ce suffici5t to d its "w dur+ ! night4 ,x has be5 sugge/$ by ,dr4 ,j4 ,c4 ,drap]1#ae ?\gh n prov$1 or ev5 r5d]$ probable1 t ! =ce ( tissue-build+ 7=ce pla/ique7 is always d]iv$ f decomposition1 or combu/ion ( organic matt]4 ,9 t case1 ! =ce ( organic-matt] =mation is d]iv$ f ! sun1 :ile ! =ce ( tissue-build+ 7:i* is relatively small7 is d]iv$ f ! combu/ion ( organic matt] ?us previ\sly =m$4 #f4 ,,f]m5tation4--,! pla/ic matt]s out ( :i* vegetable tissue is built1 & :i* are =m$ by sunlight 9 ! leaves1 are ( two k9ds1 viz41 amyloids 7dextr9e1 sug>1 />*1 cellulose71 & album9oids1 or protoplasm4 ,n[1 ! amyloids are comp>atively /able1 & d n spontane\sly decompose2 b ! album9oids n only decompose spontane\sly !mselves1 b drag d[n ! amyloids ) :i* !y are associat$ into concurr5t decomposition--n only *ange !mselves1 b propagate a *ange into amyloids4 ,album9oids1 9 v>i\s /ages & k9ds ( decomposition1 are call$ f]m5ts4 ,! propagat$ *ange 9 amyloids is call$ f]m5tation4 ,by v>i\s k9ds ( f]m5ts1 amyloids are ?us dragg$ d[n /ep by /ep to ! m9]al k+dom1 viz41 to ,,co & ,h,o4 ,! accompany+ table exhibits ! v>i\s /ages ( ! desc5t ( />*1 & ! f]m5ts by :i* !y are effect$3 #a4 ,/>* #b4 ,dextr9e ,dia/ase4 #c4 ,sug> #d4 ,alcohol & ,,co ,yea/4 #e4 ,acetic acid ,"m ( v9eg>4 #f4 ,,co & ,h,o ,m\ld4 ,by appropriate means1 ! process ( desc5t may be /opp$ on any "o ( ^! planes4 ,by f> too mu* is1 un=tunately1 /opp$ on ! f\r? plane4 ,! manufactur] & *emi/ may det]m9e ! d[nw>d *ange ?r\gh all ! planes1 & ! *emi/ has rec5tly succe$$ 9 asc5d+ aga9 to ,no4 #d2 b ! plant asc5ds & desc5ds ! scale at pleasure 7avoid+1 h[ev]1 ! f\r? & fif?71 & ev5 passes at "o /ep f ! l[e/ to ! highe/4 ,n[1 x w be se5 by ! table t1 connect$ ) ea* ( ^! desc5sive *anges1 !re is a peculi> f]m5t associat$4 ,dia/ase det]m9es ! *ange f />* to dextr9e & sug>--sac*>ification2 yea/1 ! *ange f sug> to alcohol--f]m5tation2 "m ( v9eg>1 ! *ange f alcohol to acetic acid--acetification2 & a peculi> m\ld1 ! *ange f acetic acid to ,,co & wat]4 ,b :at is f> m wond]ful & significant is1 t1 associat$ ) ea* ( ^! f]m5ts1 except dia/ase1 & !re=e ) ea* ( ^! desc5sive *anges1 except ! *ange f />* to sug>1 or sac*>ification1 !re is a peculi> =m ( life4 ,associat$ ) alcoholic f]m5tation1 !re is ! yea/-plant2 ) acetification1 ! v9eg>-plant2 & ) ! decomposition ( v9eg>1 a peculi> k9d ( m\ld4 ,we w take ! "o :i* is be/ und]/ood1 viz41 yea/-plant 7sac*>omyce71 & its relation to alcoholic f]m5tation4 ,x is well kn[n t1 9 connection ) alcoholic f]m5tation1 !re is a peculi> unicell$ plant :i* gr[s & multiplies4 ,f]m5tation nev] takes place )\t ! pres5ce ( ?is plant2 ?is plant nev] gr[s )\t produc+ f]m5tation1 & ! rapidity ( ! f]m5tation is 9 exact proportion to ! rapidity ( ! gr[? ( ! plant4 ,b1 z f> z ,i "k1 ! fact has n be5 di/9ctly br\ght out t ! decomposition ( ! sug> into alcohol & c>bonic acid furni%es ! =ce by :i* ! plant gr[s & multiplies4 ,if ! gr[+ cells ( ! yea/-plant be obs]v$ "u ! microscope1 x w be se5 t ! c>bonic-acid bubbles =m1 & !re=e probably ! decomposition ( sug> takes place only 9 contact ) ! surface ( ! yea/-cells4 ,! yea/-plant n only assimilates matt]1 b also =ce4 ,x decomposes ! sug> 9 ord] t x may assimilate ! *emical =ce set free4 ,we h already said t ! *ange f />* to sug>1 det]m9$ by dia/ase 7sac*>ification71 is ! only "o 9 connection ) :i* !re is no life4 ,n[1 x is a mo/ significant fact1 9 ?is connection1 t ?is is also ! only *ange :i* is n1 9 a prop] s5se1 desc5sive1 or1 at lea/1 :]e !re is no decomposition4 ,we n[ pass f ! ph5om5a ( vegetable to ! ph5om5a ( animal life4 #g4 ,,developm5t ,,( ,,! ,,egg ,,9 ,,incubation4--,! developm5t ( ! egg 9 incubation is v simil> to ! g]m9ation ( a se$4 ,an egg consi/s ( album9\s & fatty matt]s1 s inclos$ t1 :ile oxyg5 ( ! air is admitt$1 nutri5t matt]s are exclud$4 ,dur+ incubation ! egg *anges into an embryo2 x passes f an almo/ unorganiz$ to a highly-organiz$ condition1 f a l[] to a high] condition4 ,!re is "w done3 !re mu/ be exp5diture ( =ce2 b1 z we h already se51 vital =ce is always d]iv$ f decomposition4 ,b1 z ! matt]s to be decompos$ are n tak5 ab extra1 ! egg mu/ consume itself2 t x does s1 is prov$ by ! fact t 9 incubation ! egg absorbs oxyg51 elim9ates ,,co & probably ,h,o1 & loses weight4 ,z 9 ! se$1 a portion ( ! matt]s conta9$ 9 ! egg is consum$ 9 ord] to create =ce to organize ! rema9d]4 ,matt] runs d[n f plane ,no4 #d to plane ,no4 #b1 & g5]ates =ce to d ! "w ( organization on plane ,no4 #d4 ,! am\nt ( ,,co & ,h,o =m$1 & !re=e ! loss ( weight1 is a measure ( ! am\nt ( pla/ic "w done4 #h4 ,,developm5t ,,)9 ,,! ,,*rysalis ,,%ell4--,x is well kn[n t _m insects em]ge f ! egg n 9 _! f9al =m1 b 9 a wormlike =m1 call$ a l>va4 ,aft] ?is !y pass into a second passive /ate1 9 :i* !y are aga9 cov]$ ) a k9d ( %ell--a sort ( second egg-/ate1 call$ ! *rysalis4 ,f ?is !y aga9 em]ge z ! p]fect insect4 ,! butt]fly is ! mo/ famili>1 z well z ! be/1 illu/ration ( ^! *anges4 ,! l>va or cat]pill> eats ) enorm\s voracity1 & gr[s v rapidly4 ,:5 its gr[? is complete1 x cov]s itself ) a %ell1 & rema9s p]fectly passive & almo/ immovable = _m days or weeks4 ,dur+ ?is p]iod ( quiesc5ce ( animal functions !re are1 h[ev]1 ! mo/ important *anges go+ on )94 ,! w+s & legs are =m$1 ! muscles are aggregat$ 9 bundles = mov+ ^! app5dages1 ! n]v\s sy/em is m highly develop$1 ! m\?-organs & alim5t>y canal are greatly *ang$ & m highly organiz$1 ! simple eyes are *ang$ into comp\nd eyes4 ,n[1 all ?is requires exp5diture ( =ce1 & !re=e decomposition ( matt]2 b no food is tak51 !re=e ! *rysalis mu/ consume its own sub/ance1 & !re=e lose weight4 ,x does s2 ! weight ( ! em]g+ butt]fly is 9 _m cases n "o-t5? t ( ! cat]pill>4 ,=ce is /or$ up 9 ! =m ( organic matt] only to be consum$ 9 do+ pla/ic "w4 #i4 ,,mature ,,animals4--,:5ce d animals d]ive _! vital =ce8 ,i answ]1 f ! decomposition ( _! food & ! decomposition ( _! tissues4 ,plants1 z we h se51 d]ive _! vital =ce f ! decomposition ( _! m9]al food4 ,b ! *emical comp\nds on :i* plants fe$ are v /able4 ,_! decomposition requires a peculi> & complex contrivance = ! reception & utilization ( sunlight4 ,^! conditions are want+ 9 animals4 ,animals1 !re=e1 _c fe$ on *emical comp\nds ( ! m9]al k+dom2 !y mu/ h organic food :i* easily runs into decomposition2 !y mu/ fe$ on ! vegetable k+dom4 ,animals are di/+ui%$ f vegetables by incessant decay 9 e tissue--a decay :i* is proportional to animal activity4 ,?is incessant decay necessitates incessant repair1 s t ! animal body has be5 lik5$ to a temple on :i* two opposite =ces are at "w 9 e "p1 ! "o te>+ d[n1 ! o!r repair+ ! brea* z fa/ z made4 ,9 vegetables no su* incessant decay has ev] be5 made out4 ,if x exi/s1 x mu/ be v trifl+ 9 comp>ison4 ,protoplasm1 x is true1 is tak5 up f ! old] p>ts ( vegetables1 & ^! p>ts die2 b ! protoplasm does n seem to decompose1 b is us$ aga9 = tissue-build+4 ,?us ! int]nal activity ( animals is ( two k9ds1 tissue-de/roy+ & tissue-build+2 :ile t ( plants seems to be1 pr9cipally1 at lea/1 ( "o k9d1 tissue-build+4 ,animals use food = =ce & repair & gr[?1 & 9 ! mature animal only = =ce & repair4 ,plants1 except 9 reproduction1 use food almo/ :olly = gr[?--!y nev] /op gr[+4 ,n[1 ! food ( animals is ( two k9ds1 amyloids & album9oids4 ,! c>nivora fe$ entirely on album9oids2 h]bivora on bo? amyloids & album9oids4 ,all ?is food comes f ! vegetable k+dom1 directly 9 ! case ( h]bivora1 indirectly 9 ! case ( c>nivora4 ,animals _c make organic matt]4 ,n[1 ! tissues ( animals are :olly album9oid4 ,x is obvi\s1 !re=e1 t = ! repair ( ! tissues ! food mu/ be album9oid4 ,! amyloid food1 !re=e 7&1 z we %all see 9 c>nivora1 mu* ( ! album9oid71 mu/ be us$ :olly = =ce4 ,z coal or wood1 burn$ 9 a /eam-eng9e1 *anges *emical into me*anical en]gy1 s food1 9 excess ( :at is us$ = repair1 is burn$ up to produce animal activity4 ,let u trace m accurately ! orig9 ( animal =ce by examples4 #aj4 ,,c>nivora4--,! food ( c>nivora is entirely album9oid4 ,! idea ( ! old] physiologi/s1 9 reg>d to ! use ( ?is food1 seems to h be5 z foll[s3 ,album9oid matt] is exce$+ly un/able2 x is matt] rais$1 ) mu* difficulty & aga9/ *emical =ces1 high1 & delicately balanc$ on a p9nacle1 9 a /ate ( un/able equilibrium1 = a brief "t1 & !n ru%es d[n aga9 into ! m9]al k+dom4 ,! animal tissues1 be+ =m$ ( album9oid matt]1 are %ort-liv$2 ! p>ts are con/antly dy+ & decompos+2 ! law ( dea? necessitates ! law ( reproduction2 decomposition necessitates repair1 & !re=e food = repair4 ,b ! =ce by :i* repair is effect$ 0 = !m1 & = _m physiologi/s n[1 und]iv$1 innate4 ,b ! doctr9e ma9ta9$ by me 9 ! pap] ref]r$ to is1 t ! decomposition ( ! tissues creates n only ! necessity1 b also ! =ce1 ( repair4 ,suppose1 9 ! fir/ place1 a c>nivor\s animal uses j en\gh food to repair ! tissues1 & no m--say an ounce4 ,!n ,i say ! ounce ( tissue decay$ n only necessitates ! ounce ( album9\s food = repair1 b ! decomposition sets free ! =ce by :i* ! repair is effect$4 ,b x w be p]haps object$ t ! =ce w\ld all be consum$ 9 repair1 & none left = animal activity ( all k9ds4 ,i answ]3 x w\ld n all be us$ up 9 repair1 =1 ! food be+ already album9oid1 !re is probably little exp5diture ( =ce necess>y to *ange x into tissue2 :ile1 on ! o!r h&1 ! =ce g5]at$ by ! decomposition ( tissue into ,,co1 ,h,o1 & urea1 is v great--! asc5sive *ange is small1 ! desc5sive *ange is great4 ,! decomposition ( "o ounce ( album9\s tissue into ,,co1 ,h,o1 & urea1 w\ld !re=e create =ce suffici5t n only to *ange "o ounce ( album9\s matt] into tissue1 b also leave a consid]able am\nt = animal activities ( all k9ds4 ,a c]ta9 quantity ( matt]1 runn+ d[n f plane ,no4 #d to plane ,no4 #b1 creates =ce en\gh n only to move ! same quantity ( matt] ab\t on plane ,no4 #d1 b also to d mu* o!r "w besides4 ,x is probable1 h[ev]1 t ! wants ( animal activity are s imm$iate & urg5t t1 "u ^! conditions1 mu* food w\ld be burn$ = ?is purpose1 & w\ld n rea* ! tissues1 & ! tissues w\ld be imp]fectly repair$1 & w\ld !re=e wa/e4 ,take1 next1 ! c>nivor\s animal full f$4 ,9 ?is case !re c be no d\bt t1 :ile a portion ( ! food goes to repair ! tissues1 by f> ! l>g] portion is consum$ 9 ! blood1 & passes away p>tly z ,,co & ,h,o ?r\gh ! lungs1 & p>tly z urea ?r\gh ! kidneys4 ,?is "p is us$1 & c be ( use only1 to create =ce4 ,! food ( c>nivora1 !re=e1 goes p>tly to tissue-build+1 & p>tly to create heat & =ce4 ,! =ce ( c>nivor\s animals is d]iv$ p>tly f decompos+ tissues & p>tly f food-excess consum$ 9 ! blood4 #aa4 ,,h]bivora4--,! food ( h]bivora & ( man is mix$--p>tly album9oid & p>tly amyloid4 ,9 man1 d\btless1 ! album9oids are usually 9 excess ( :at is requir$ = tissue-build+2 b 9 h]bivora1 probably1 ! album9oids are n 9 excess ( ! requirem5ts ( ! decompos+ tissues4 ,9 ?is case1 !re=e1 ! :ole ( ! album9oids is us$ = tissue-mak+1 & ! :ole ( ! amyloids = =ce-mak+4 ,9 ?is class1 !re=e1 ^! two classes ( food may be call$ tissue-food & =ce-food4 ,! =ce ( ^! animals1 !re=e1 is d]iv$ p>tly f ! decomposition ( ! tissues1 b pr9cipally f ! decomposition & combu/ion ( ! amyloids & fats4 ,"s physiologi/s speak ( ! amyloid & fat food z be+ burn$ to keep up ! animal heat2 b x is evid5t t ! prime object 9 ! body1 z 9 ! /eam-eng9e1 is n heat1 b =ce4 ,heat is a m]e condition & p]haps a necess>y concomitant ( ! *ange1 b evid5tly n ! prime object4 ,9 tropical regions ! heat is n want$4 ,9 ! /eam-eng9e1 *emical en]gy is fir/ *ang$ into heat1 & heat into me*anical en]gy2 9 ! body ! *ange is1 probably1 mu* ( x direct1 & n ?r\gh ! int]m$iation ( heat4 #ab4 ,we see at once1 f ! above1 :y x is t plants _c fe$ on elem5ts1 viz41 because _! food mu/ be decompos$ 9 ord] to create ! organic matt] out ( :i* all organisms are built4 ,?is elevation ( matt]1 :i* takes place 9 ! gre5 leaves ( plants1 is ! />t+-po9t ( life2 ^u x alone is bas$ ! possibility ( ! exi/5ce ( ! organic k+dom4 ,! runn+ d[n ( ! matt] !re rais$ det]m9es ! vital ph5om5a ( g]m9ation1 ( pale plants1 & ev5 ( "s ( ! vital ph5om5a ( gre5 plants1 & all ! vital ph5om5a ( ! animal k+dom4 ,! /ability ( *emical comp\nds1 usable z plant-food1 is su* t a peculi> contrivance & peculi> conditions f\nd only 9 ! gre5 leaves ( plants are necess>y = _! decomposition4 ,we see1 !re=e1 also1 :y animals z well z pale plants _c fe$ on m9]al matt]4 ,we easily see also :y ! animal activity ( c>nivora is great] ?an t ( h]bivora1 = ! am\nt ( =ce necess>y = ! assimilation ( _! album9oid food is small1 & !re=e a l>g] am\nt is left ov] = animal activity4 ,_! food is already on plane ,no4 #d2 assimilation1 !re=e1 is little m ?an a %ift+ on ! plane ,no4 #d f a liquid to a solid condition--f liquid album9oid ( ! blood to solid album9oid ( ! tissues4 ,we see also :y ! int]nal activity ( plants may conceivably be only ( "o k9d2 =1 draw+ _! =ce f ! sun1 tissue-mak+ is n necess>ily dep5d5t on tissue-decay4 ,:ile1 on ! o!r h&1 ! int]nal activity ( animals mu/ be ( two k9ds1 decay & repair2 = animals always draw a portion ( _! =ce1 & />v+ animals ! :ole ( _! =ce1 f decay+ tissue4 #ac4 ,!re are sev]al g5]al ?\ghts sugge/$ by ?is subject1 :i* ,i wi% to pres5t 9 conclusion3 a4 ,we h said !re are f\r planes ( matt] rais$ "o above ! o!r3 #a4 ,elem5ts2 #b4 ,*emical comp\nds2 #c4 ,vegetables2 #d4 ,animals4 ,_! relative position is truly repres5t$ ?us3 #d4 ,animals4 #c4 ,plants4 #b4 ,*emical comp\nds4 #a4 ,elem5ts4 ,n[1 !re are also f\r planes ( =ce simil>ly relat$ to ea* o!r1 viz41 physical =ce1 *emical =ce1 vitality1 & w4 ,on ! fir/ plane ( matt] op]ates physical =ce only2 = *emical =ce imm$iately raises matt] into ! second plane4 ,on ! second plane op]ates1 9 addition to physical1 also *emical =ce4 ,on ! ?ird plane op]ates1 9 addition to physical & *emical1 also vital =ce4 ,on ! f\r? plane1 9 addition to physical1 *emical1 & vital1 also ! =ce *>act]i/ic ( animals1 viz41 w4#af ,) ea* elevation !re is a peculi> =ce add$ to ! already exi/+1 & a peculi> gr\p ( ph5om5a is ! result4 ,z matt] only rises /ep by /ep f plane to plane1 & nev] two /eps at a "t1 s also =ce1 9 its trans=mation into high] =ms ( =ce1 rises only /ep by /ep4 ,physical =ce does n become vital except ?r\gh *emical =ce1 & *emical =ce does n become w except ?r\gh vital =ce4 ,aga91 we h comp>$ ! v>i\s grades ( matt]1 n to a gradually ris+ incl9$ plane1 b to successive planes rais$ "o above ! o!r4 ,!re are1 no d\bt1 "s int]m$iate conditions2 b1 z a broad1 g5]al fact1 ! *anges f plane to plane are sudd54 ,n[1 ! same is true also ( ! =ces op]at+ on ^! planes--( ! diff]5t grades ( =ce1 & _! correspond+ gr\ps ( ph5om5a4 ,! *ange f "o grade to ano!r1 z f physical to *emical1 or f *emical to vital1 is n1 z f> z we c see1 by slid+ scale1 b sudd5ly4 ,! gr\ps ( ph5om5a :i* we call physical1 *emical1 vital1 animal1 rational1 & moral1 d n m]ge into ea* o!r by ins5sible gradations4 ,9 ! asc5sive scale ( =ces1 9 ! evolution ( ! high] =ces f ! l[]1 !re are places ( rapid1 p>oxysmal *ange4 b4 ,vital =ce is trans=m$ into physical & *emical =ces2 b x is n on t acc\nt id5tical ) physical & *emical =ce1 & !re=e we ought n1 z "s w\ld h u1 disc>d ! t]m vital =ce4 ,!re are two opposite errors on ?is subject3 "o is ! old error ( reg>d+ vital =ce z some?+ innate1 und]iv$1 hav+ no relation to ! o!r =ces ( ,nature2 ! o!r is ! new error ( reg>d+ ! =ces ( ! liv+ body z no?+ b ord9>y physical & *emical =ces1 & !re=e insi/+ t ! use ( ! t]m vital =ce is absurd & injuri\s to sci5ce4 ,! old error is /ill preval5t 9 ! popul> m9d1 & /ill haunts ! m9ds ( _m physiologi/s2 ! new error is app>5tly a revulsion f ! o!r1 & is !re=e common among ! mo/ advanc$ sci5tific m9ds4 ,!re are _m ( ! be/ sci5ti/s :o ridicule ! use ( ! t]m vital =ce1 or vitality1 z a remnant ( sup]/ition2 & yet ! same m5 use ! words gravity1 magnetic =ce1 *emical =ce1 physical =ce1 etc4 ,vital =ce is n und]iv$--is n unrelat$ to o!r =ces--is1 9 fact1 correlat$ ) !m2 b x is nev]!less a di/9ct =m ( =ce1 f> m di/9ct ?an any o!r =m1 unless x be /ill high] =ms1 & !re=e bett] entitl$ to a di/9ct "n ?an any l[] =m4 ,ea* =m ( =ce gives rise to a peculi> gr\p ( ph5om5a1 & ! /udy ( ^! to a peculi> dep>tm5t ( sci5ce4 ,n[1 ! gr\p ( ph5om5a call$ vital is m peculi>1 & m diff]5t f o!r gr\ps1 ?an ^! are f ea* o!r2 & ! sci5ce ( physiology is a m di/9ct dep>tm5t ?an ei!r physics or *emi/ry2 & !re=e ! =m ( =ce :i* det]m9es ^! ph5om5a is m di/9ct1 & bett] entitl$ to a di/9ct "n1 ?an ei!r physical or *emical =ces4 ,de ,c&olle1 9 a rec5t pap]1#ag sugge/s ! t]m vital movem5t in/ead ( vital =ce2 b c we conceive ( movem5t )\t =ce8 ,&1 if ! movem5t is peculi>1 s also is ! =m ( =ce4 c4 ,vital is trans=m$ physical & *emical =ces2 true1 b ! necess>y & v peculi> condition ( ?is trans=mation is ! previ\s exi/5ce !n & !re ( liv+ matt]4 ,!re is some?+ s wond]ful 9 ?is peculi>ity ( vital =ce t ,i mu/ dwell on x a little4 ,elem5ts br\ght 9 contact ) ea* o!r "u c]ta9 physical conditions--p]haps heat or electricity--unite & rise into ! second plane1 i4 e41 ( *emical comp\nds2 s also sev]al elem5ts1 ,c1 ,h1 ,o1 & ,n1 etc41 br\ght 9 contact ) ea* o!r "u c]ta9 physical or *emical conditions1 su* z light1 nasc5cy1 etc41 unite & rise into plane ,no4 #c1 i4 e41 =m organic matt]4 ,9 bo? cases !re is *emical union "u c]ta9 physical conditions2 b 9 ! latt] !re is "o unique condition1 viz41 ! previ\s exi/5ce !n & !re ( organic matt]1 "u ! guidance ( :i* ! trans=mation ( matt] takes place4 ,9 a ^w1 organic matt] is necess>y to produce organic matt]2 !re is "h a law ( l produc+ l--!re is an assimilation ( matt]4 ,aga91 physical =ce *anges into o!r =ms ( physical =ce1 or into *emical =ce1 "u c]ta9 physical conditions2 s also physical & *emical =ces are *ang$ into vital =ce "u c]ta9 physical conditions4 ,b1 9 addition1 !re is "o altoge!r unique condition ( ! latt] *ange1 viz41 ! previ\s exi/5ce !n & !re ( vital =ce4 ,"h1 aga91 l produces l--"h1 aga91 !re is assimilation ( =ce4 ,?is law ( l produc+ l--?is law ( assimilation ( matt] & =ce--runs ?r\gh\t all vital ph5om5a1 ev5 to ! m9ute/ details4 ,x is a univ]sal law ( g5]ation1 & det]m9es ! exi/5ce ( species2 x is ! law ( =mation ( organic matt] & organic =ce2 x det]m9es all ! v>ieties ( organic matt] :i* we call tissues & organs1 & all ! v>ieties ( organic =ce :i* we call functions4 ,! same nutri5t pabulum1 end[$ ) ! same prop]ties & p[]s1 c>ri$ to all p>ts ( a complex organism by ?is wond]ful law ( l produc+ l1 is *ang$ into ! mo/ v>i\s =ms & end[$ ) ! mo/ v>i\s p[]s4 ,!re are c]ta9ly limits & exceptions to ?is law1 h[ev]2 o!rwise diff]5tiation ( tissues1 organs1 & functions1 c\ld n take place 9 embryonic developm5t2 b ! limits & exceptions are !mselves subject to a law ev5 m wond]ful ?an ! law ( l produc+ l itself1 viz41 ! law ( evolution4 ,!re is 9 all organic nature1 :e!r organic k+dom1 organic individual1 or organic tissues1 a law ( v>iation1 /ronge/ 9 ! e>ly /ages1 limit$ v /rictly by ano!r law--! law ( inh]itance1 ( l produc+ l4 d4 ,we h se5 t all developm5t takes place at ! exp5se ( decay--all elevation ( "o ?+1 9 "o place1 at ! exp5se ( correspond+ runn+ d[n ( some?+ else 9 ano!r place4 ,=ce is only transf]r$ & trans=m$4 ,! plant draws its =ce f ! sun1 & !re=e :at ! plant ga9s ! sun loses4 ,animals draw f plants1 & !re=e :at ! animal k+dom ga9s ! vegetable k+dom loses4 ,aga91 an egg1 a se$1 or a *rysalis1 develop+ to a high] condition1 & yet tak+ no?+ ab extra1 mu/ lose weight4 ,"s "p mu/ run d[n1 9 ord] t ! rema9d] %\ld be rais$ to a high] condition4 ,! am\nt ( evolution is measur$ by ! loss ( weight4 ,by ! law ( cons]vation ( =ce1 x is inconceivable t x %\ld be o!rwise4 ,evid5tly1 !re=e1 9 ! univ]se1 tak5 z a :ole1 evolution ( "o "p mu/ be at ! exp5se ( "s o!r "p4 ,! evolution or developm5t ( ! :ole cosmos--( ! :ole univ]se ( matt]--z a unit1 by =ces )9 itself1 accord+ to ! doctr9e ( cons]vation ( =ce1 is inconceivable4 ,if !re be any su* evolution1 at all comp>able ) any kn[n =m ( evolution1 x c only take place by a con/ant increase ( ! :ole sum ( en]gy1 i4 e41 by a con/ant influx ( div9e en]gy--= ! same quantity ( matt] 9 a high] condition mu/ embody a great] am\nt ( en]gy4 e4 ,f9ally1 z organic matt] is s mu* matt] tak5 f ! common fund ( matt] ( e>? & air1 embodi$ = a brief space1 to be aga9 by dea? & decomposition return$ to t common fund1 s also x w\ld seem t ! organic =ces ( ! liv+ bodies ( plants & animals may be reg>d$ z s mu* =ce drawn f ! common fund ( physical & *emical =ces1 to be aga9 all refund$ by dea? & decomposition4 ,yes1 by decomposition2 we c und]/& ?is4 ,b dea?6 c we detect any ?+ return$ by simple dea?8 ,:at is ! nature ( ! diff]5ce betwe5 ! liv+ organism & a dead organism8 ,we c detect none1 physical or *emical4 ,all ! physical & *emical =ces )drawn f ! common fund ( ,nature1 & embodi$ 9 ! liv+ organism1 seem to be /ill embodi$ 9 ! dead until little by little x is return$ by decomposition4 ,yet ! diff]5ce is imm5se1 is inconceivably great4 ,:at is ! nature ( ?is diff]5ce express$ 9 ! =mula ( mat]ial sci5ce8 ,:at is x t is gone1 & :i!r is x gone8 ,!re is some?+ "h :i* sci5ce _c yet und]/&4 ,yet x is j ?is loss :i* takes place 9 dea?1 & be=e decomposition1 :i* is 9 ! highe/ s5se vital =ce4 ,let no "o f ! above views1 or f simil> views express$ by o!rs1 draw ha/y conclusions 9 favor ( a pure mat]ialism4 ,=ce & matt]1 or _s & matt]1 or ,god & ,nature1 ^! are ! opposite poles ( philosophy--!y are ! opposite poles ( ?\ght4 ,!re is no cle> ?9k+ )\t !m4 ,n only religion & virtue1 b sci5ce & philosophy1 _c ev5 exi/ )\t !m4 ,! belief 9 _s1 l ! belief 9 matt]1 re/s on its own basis ( ph5om5a4 ,! true doma9 ( philosophy is to reconcile ^! ) ea* o!r4 ,,footnotes3 #aa ,9 rec5t works ! ^w en]gy is us$ to designate active or work+ =ce z di/+ui%$ f passive or non-work+ =ce4 ,x is 9 ?is work+ condition only t =ce is cons]v$1 & !re=e cons]vation ( en]gy is ! prop] expression4 ,nev]!less1 s9ce ! di/9ction betwe5 =ce & en]gy is imp]fectly or n at all def9$ 9 ! high] =ms ( =ce1 & especially 9 ! doma9 ( life1 ,i h pref]r$ 9 ?is article to use ! ^w =ce 9 ! g5]al s5se usual until rec5tly4 #ab ,am]ican ,j\rnal ( ,sci5ce1 ,novemb]1 #ahei4 ,philadelphia ,magaz9e1 vol4 xix41 p4 #acc4 #ac ,9 #ahde ,dr4 ,j4 ,r4 ,may] publi%$ a pap] on 8,organic ,motion & ,nutrition40 ,i h n se5 x4 #ad ,= m full acc\nt1 see my pap]1 ,am]ican ,j\rnal ( ,sci5ce1 ,novemb]1 #ahei1 six? & sev5? heads4 #ae ,am]ican ,j\rnal ( ,sci5ce1 ,novemb]1 #ahgb4 ,! exp]im5ts ( ,dr4 ,drap] are inconclusive1 because !y are made on se$l+s1 :i*1 until _! supply ( organic food is exhau/$1 are indep5d5t ( sunlight4 #af ,i might add /ill ano!r plane & ano!r =ce1 viz41 ! human plane1 on :i* op]ate1 9 addition to all ! l[] =ces1 also free-w & reason4 ,i d n speak ( ^!1 only because !y lie beyond ! pres5t k5 ( inductive sci5ce4 #ag ,ar*ives des ,sci5ces1 vol4 xlv41 p4 #cde1 ,decemb]1 #ahgb4 ,,correlation ,,( ,,n]v\s ,,& ,,m5tal ,,=ces4 ,,by ,,alex&] ,,ba91 ,,ll4 ,d41 ,,pr(essor ,,( ,,logic ,,& ,,m5tal ,,philosophy ,,9 ,,! ,,univ]sity ,,( ,,ab]de54 ,,! ,,correlation ,,( ,,n]v\s ,,& ,,m5tal ,,=ces4 ,! doctr9e call$ ! correlation1 p]si/5ce1 equival5ce1 transmutability1 inde/ructibility ( =ce1 or ! cons]vation ( en]gy1 is a g5]ality ( su* compass t no s+le =m ( words seems capable ( fully express+ x2 & diff]5t p]sons may pref] diff]5t /atem5ts ( x4 ,my und]/&+ ( ! doctr9e is1 t !re are five *ief p[]s or =ces 9 ,nature3 "o me*anical1 or mol>1 ! mom5tum ( mov+ matt]2 ! o!rs molecul>1 or embodi$ 9 ! molecules1 also suppos$ 9 motion--^! are1 heat1 light1 *emical =ce1 electricity4 ,to ^! p[]s1 :i* are unque/ionable & di/9ct1 x is usual to add vital =ce1 ( :i*1 h[ev]1 x is difficult to speak z a :ole2 b "o memb] ( our vital en]gies1 ! n]ve-=ce1 alli$ to electricity1 fully des]ves to rank 9 ! correlation4 ,tak+ ! "o me*anical =ce1 & ^? ?ree ( ! molecul> nam$ heat1 *emical =ce1 electricity1 !re has n[ be5 e/abli%$ a def9ite rate ( commutation1 or ex*ange1 :5 any "o passes into any o!r4 ,! me*anical equival5t ( heat1 ! #ggb foot-p\nds ( ,j\le1 expresses ! rate ( ex*ange betwe5 me*anical mom5tum & heat3 ! equival5t or ex*ange ( heat & *emical =ce is giv5 7?r\gh ! rese>*es ( ,&rews & o!rs7 9 ! figures express+ ! heat ( comb9ations2 = example1 "o p\nd ( c>bon burnt evolves heat en\gh to raise #h1jhj p\nds ( wat] "o degree1 ,c4 ,! comb9ation ( ^! to equival5ts w\ld %[ t ! consumption ( half a p\nd ( c>bon w\ld raise a man ( av]age weight to ! highe/ summit ( ! ,himalayas4 ,x is an ess5tial "p ( ! doctr9e1 t =ce is nev] absolutely creat$1 & nev] absolutely de/roy$1 b m]ely transmut$ 9 =m or manife/ation4 ,z appli$ to liv+ bodies1 ! foll[+ are ! usual positions4 ,9 ! gr[? ( plants1 ! =ces ( ! sol> ray--heat & light--are exp5d$ 9 decompos+ 7or deoxidiz+7 c>bonic acid & wat]1 & 9 build+ up ! liv+ tissues f ! lib]at$ c>bon & ! o!r elem5ts2 all :i* =ce is giv5 up :5 ^! tissues are consum$1 ei!r z fuel 9 ord9>y combu/ion1 or z food 9 animal combu/ion4 ,x is ?is animal combu/ion ( ! matt] ( plants1 & ( animals 7f$ on plants7--namely1 ! reoxidation ( c>bon1 hydrog51 etc4--t yields all ! manife/ations ( p[] 9 ! animal frame4 ,&1 9 p>ticul>1 x ma9ta9s 7#a7 a c]ta9 w>m? or temp]ature ( ! :ole mass1 aga9/ ! cool+ p[] ( surr\nd+ space2 x ma9ta9s 7#b7 me*anical en]gy1 z muscul> p[]2 & x ma9ta9s 7#c7 n]v\s p[]1 or a c]ta9 fl[ ( ! influ5ce circulat+ ?r\gh ! n]ves1 :i* circulation ( influ5ce1 besides react+ on ! o!r animal processes--muscul>1 gl&ul>1 etc4--has = its di/+ui%+ concomitant ! ,,m9d4 ,! ext5sion ( ! correlation ( =ce to m9d1 if at all compet5t1 mu/ be made ?r\gh ! n]ve-=ce1 a g5u9e memb] ( ! correlat$ gr\p4 ,v s]i\s difficulties beset ! proposal1 b !y are n insup]able4 ,! hi/ory ( ! doctr9es relat+ to m9d1 z connect$ ) body1 is 9 ! highe/ degree curi\s & in/ructive1 b1 = ! purpose ( ! pres5t pap]1 we %all notice only c]ta9 lead+ /ages ( ! speculation4#ah ,n ! lea/ important position is ! ,ari/otelian2 a position 9 "s respects s\nd] ?an :at foll[$ & grew out ( x4 ,9 ,ari/otle1 we h a k9d ( gradation f ! life ( plants to ! highe/ =m ( human intellig5ce4 ,9 ! foll[+ diagram1 ! cont9u\s l9es may repres5t ! mat]ial sub/ance1 & ! dott$ l9es ! immat]ial3 ,a4 ,s\l ( ,plants4 ---- ,)\t consci\sness4 ,b4 ,animal ,s\l4 ---- ,body & m9d insep>able4 4444 ,c4 ,human ,s\l--,,n\s--,intellect4 ,i4 ,passive intellect4 ---- ,body & m9d insep>able4 4444 ,,ii4 ,active intellect--cognition ( ! highe/ pr9ciples4 4444 ,pure =m2 deta*$ f matt]2 ! prime mov] ( all2 immortal4 ,all ! phases ( life & m9d are insep>ably int]wov5 ) ! body 7:i* insep>ability is ,ari/otle's def9ition ( ! s\l7 except ! la/1 ! active n\s1 or intellect1 :i* is deta*$ f corporeal matt]1 self-subsi/+1 ! ess5ce ( ,deity1 & an immortal sub/ance1 al?\gh ! immortality is n p]sonal to ! individual4 7,! immat]iality ( ?is high] intellectual ag5t 0 net1 h[ev]1 t ?or\gh-go+ negation ( all mat]ial attributes :i* we n[ und]/& by ! ^w 8immat]ial407 ,h[ su* a self-subsi/+ & purely spiritual s\l c\ld hold communication ) ! body-leagu$ s\ls1 ,ari/otle 0 at a loss to say--! difficulty reappe>$ aft] him1 & has nev] be5 got ov]4 ,t !re %\ld be an ag5cy totally ap>t f1 & entirely transc5d+1 any kn[n p[]s ( in]t matt]1 involves no difficulty--= :o is to limit ! possibilities ( exi/5ce8 ,! p]plexity arises only :5 ?is radically new & sup]ior pr9ciple is made to be1 z x 71 (f & on ) ! mat]ial pr9ciple2 p]=m+ "s ( its functions 9 pure isolation1 & o!rs ( an analog\s k9d by ! aid ( ! l[] pr9ciple4 ,! diff]5ce betwe5 ! active & ! passive reason ( ,ari/otle is a m]e diff]5ce ( gradation2 ! support+ ag5cies assum$ by him are a total contra/ 9 k9d--wide z ! poles asund]4 ,!re is no brea* ( cont9uity 9 ! ph5om5a1 !re is an impassable *asm betwe5 _! respective f\ndations4 ,fifte5 c5turies aft] ,ari/otle1 we rea* :at may be call$ ! mod]n settlem5t ( ! relations ( m9d & body1 effect$ by ,?omas ,aqu9as4 ,he ext5d$ ! doma9 ( ! indep5d5t immat]ial pr9ciple f ! highe/ intellectual s\l ( ,ari/otle to all ! ?ree s\ls recogniz$ by him--! vegetable or plant s\l 7)\t consci\sness71 ! animal s\l 7) consci\sness71 & ! intellect ?r\gh\t4 ,! two l[] s\ls--! vegetable & ! animal--ne$ ! cop]ation ( ! body 9 ?is life2 ! intellect works )\t any bodily organ1 except t x makes use ( ! p]ceptions ( ! s5ses4 ,a4 ,vegetable or ,nutritive ,s\l4 ---- ,incorporates an immat]ial "p1 al?\gh unconsci\s4 4444 ,b4 ,animal ,s\l4 ---- ,has an immat]ial "p1 ) consci\sness4 4444 ,c4 ,intellect4 4444 ,purely immat]ial4 ,! animal s\l1 ,b1 conta9s s5sation1 appetite1 & emotion1 & is a mix$ or two-sid$ entity2 b ! intellect1 ,c1 is a purely "o-sid$ entity1 ! immat]ial4 ,?is does n relieve our p]plexities2 ! ph5om5a are /ill g5]ically alli$ & cont9u\s--s5sation passes into intellect )\t any brea* ( cont9uity2 b z reg>ds ! ag5cies1 ! transition f a mix$ or unit$ mat]ial & immat]ial sub/ance to an immat]ial sub/ance ap>t1 is a transition to a diff]5tly con/itut$ _w1 to a transc5d5tal sph]e ( exi/5ce4 ,! settlem5t ( ,aqu9as gov]n$ all ! s*ools & all ! religi\s cre$s1 until q rec5t times2 x is1 = example1 sub/antially ! view ( ,bi%op ,butl]4 ,at ! in/ance ( mod]n physiology1 h[ev]1 x has und]gone modifications4 ,! dep5d5ce ( purely intellectual op]ations1 z memory1 ^u ! mat]ial processes1 has be5 reluctantly admitt$ by ! p>tisans ( an immat]ial pr9ciple2 an admission incompatible ) ! isolation ( ! intellect 9 ,ari/otle & 9 ,aqu9as4 ,?is m ?or\gh-go+ connection ( ! m5tal & ! physical has l$ to a new =m ( express+ ! relation%ip1 :i* is ne>] ! tru?1 )\t be+1 9 my judgm5t1 q accurate4 ,x is n[ (t5 said ! m9d & ! body act ^u ea* o!r2 t nei!r is all[$1 s to speak1 to pursue its c\rse alone--!re is a con/ant int]f]5ce1 a mutual influ5ce betwe5 ! two4 ,?is view is liable to ! foll[+ objections3 #a4 ,9 ! fir/ place1 x assumes t we are entitl$ to speak ( m9d ap>t f body1 & to affirm its p[]s & prop]ties 9 t sep>ate capacity4 ,b ( m9d ap>t f body we h no direct exp]i5ce1 & absolutely no k4 ,! w9d may act ^u ! sea1 & ! waves may react ^u ! w9d2 b ! ag5ts are kn[n 9 sep>ation--!y are se5 to exi/ ap>t be=e ! %ock ( collision2 b we are n p]mitt$ to see a m9d act+ ap>t f its mat]ial companion4 #b4 ,9 ! second place1 we h e reason = believ+ t !re is an unbrok5 mat]ial succession1 side by side ) all our m5tal processes4 ,f ! +ress ( a s5sation1 to ! outgo+ responses 9 action1 ! m5tal succession is n = an in/ant dissev]$ f a physical succession4 ,a new prospect bur/s ^u ! view2 !re is a m5tal result ( s5sations1 emotion1 ?\ght1 t]m9at+ 9 outw>d displays ( spee* or ge/ure4 ,p>allel to ?is m5tal s]ies is ! physical s]ies ( facts1 ! successive agitation ( ! physical organs1 call$ ! eye1 ! ret9a1 ! optic n]ve1 optic c5tres1 c]ebral hemisph]es1 outgo+ n]ves1 muscles1 etc4 ,!re is an unbrok5 physical circle ( effects1 ma9ta9$ :ile we g ! r\nd ( ! m5tal circle ( s5sation1 emotion1 & ?\ght4 ,x w\ld be incompatible ) e ?+ we "k ( ! c]ebral action to suppose t ! physical *a9 ends abruptly 9 a physical void1 occupi$ by an immat]ial sub/ance2 :i* immat]ial sub/ance1 aft] work+ alone1 imp>ts its results to ! o!r edge ( ! physical break1 & det]m9es ! active response--two %ores ( ! mat]ial ) an int]v5+ ocean ( ! immat]ial4 ,!re is1 9 fact1 no rupture ( n]v\s cont9uity4 ,! only t5able supposition is1 t m5tal & physical proce$ toge!r1 z individual tw9s4 ,:51 !re=e1 we speak ( a m5tal cause1 a m5tal ag5cy1 we h always a two-sid$ cause2 ! effect produc$ is n ! effect ( m9d alone1 b ( m9d 9 company ) body4 ,t m9d %\ld h op]at$ on ! body1 is z mu* z to say t a two-sid$ ph5om5on1 "o side be+ bodily1 c influ5ce ! body2 x is1 aft] all1 body act+ ^u body4 ,:5 a %ock ( fe> p>alyzes dige/ion1 x is n ! emotion ( fe>1 9 ! ab/ract1 or z a pure m5tal exi/5ce1 t does ! h>m2 x is ! emotion 9 company ) a peculi>ly excit$ condition ( ! bra9 & n]v\s sy/em2 & x is ?is condition ( ! bra9 t d]anges ! /oma*4 ,:5 physical n\ri%m5t1 or physical /imulant1 act+ ?r\gh ! blood1 quiets ! m5tal irritation1 & re/ores a *e]ful tone1 x is n a bodily fact caus+ a m5tal fact by a direct l9e ( causation3 ! n\ri%m5t & ! /imulus det]m9e ! circulation ( blood to ! bra91 give a new direction to ! n]ve-curr5ts1 & ! m5tal condition correspond+ to ?is p>ticul> mode ( c]ebral action h5ce=? manife/s itself4 ,! l9e ( m5tal sequ5ce is ?us1 n m9d caus+ body1 & body caus+ m9d1 b m9d-body giv+ bir? to m9d-body2 a mu* m intelligible position4 ,= ?is d\ble or conjo9t causation1 we c produce evid5ce2 = ! s+le-h&$ causation we h no evid5ce4 ,if x 7 n my peculi> prov9ce to endeavor to cle> up ! specially metaphysical difficulties ( ! relation%ip ( m9d & body1 ,i w\ld pass ov] :at is to me ! mo/ puzzl+ circum/ance ( ! relation%ip1 & inde$ ! only real difficulty 9 ! "q4 ,i say ! real difficulty1 = factiti\s difficulties 9 abundance h be5 made out ( ! subject4 ,x is made a my/]y h[ m5tal functions & bodily functions %\ld be alli$ toge!r at all4 ,t1 h[ev]1 is no bus9ess ( ours2 we accept ?is alliance1 z we d any o!r alliance1 su* z gravity ) in]t matt]1 or light ) heat4 ,z a fact ( ! univ]se1 ! union is1 prop]ly speak+1 j z acceptable1 & z intelligible1 z ! sep>ation w\ld be1 if t 7 ! fact4 ,! real difficulty is q ano!r ?+4 ,:at ,i h 9 view is ?is3 :5 ,i speak ( m9d z alli$ ) body--) a bra9 & its n]ve-curr5ts--,i c sc>cely avoid localiz+ ! m9d1 giv+ x a local habitation4 ,i am !reupon ask$ to expla9 :at always puzzl$ ! s*oolm51 namely1 :e!r ! m9d is all 9 e "p1 or only all 9 ! :ole2 :e!r 9 tapp+ any po9t ,i may come at consci\sness1 or :e!r ! :ole me*anism is want$ = ! smalle/ portion ( consci\sness4 ,"o might p]haps turn ! "q by ! analogy ( ! telegraph wire1 or ! electric circuit1 & say t a complete circle ( action is necess>y to any m5tal manife/ation2 :i* is probably true4 ,b ?is does n meet ! case4 ,! fact is t1 all ?is "t we are speak+ ( n]ves & wires1 we are n speak+ ( m9d1 prop]ly s call$1 at all2 we are putt+ =w>d physical facts t g along ) x1 b ^! physical facts are n ! m5tal fact1 & !y ev5 preclude u f ?9k+ ( ! m5tal fact4 ,we are 9 ?is fix3 m5tal /ates & bodily /ates are utt]ly contra/$2 !y _c be comp>$1 !y h no?+ 9 common except ! mo/ g5]al ( all attributes1 degree1 & ord] 9 "t2 :5 engag$ ) "o we mu/ be oblivi\s ( all t di/+ui%es ! o!r4 ,:5 ,i am /udy+ a bra9 & n]ve communicat+1 ,i am engross$ ) prop]ties exclusively belong+ to ! object or mat]ial _w2 ,i am at t mom5t 7except by v rapid transitions or alt]nations7 unable to conceive a truly m5tal fact1 my truly m5tal consci\sness4 ,our m5tal exp]i5ce1 our feel+s & ?\ghts1 h no ext5sion1 no place1 no =m or outl9e1 no me*anical division ( p>ts2 & we are incapable ( att5d+ to any ?+ m5tal until we %ut (f ! view ( all t4 ,walk+ 9 ! c\ntry 9 spr+1 our m9d is occupi$ ) ! foliage1 ! bloom1 & ! grassy meads1 all purely objective ?+s2 we are sudd5ly & /rongly arre/$ by ! odor ( ! ,may-blossom2 we give way = a mom5t to ! s5sation ( sweetness3 = t mom5t ! objective reg>ds cease2 we ?9k ( no?+ ext5d$2 we are 9 a /ate :]e ext5sion has no foot+2 !re is1 to u1 place no long]4 ,su* /ates are ( %ort duration1 m]e fits1 glimpses2 !y are con/antly %ift$ & alt]nat$ ) object /ates1 b :ile !y la/ & h _! full p[] we are 9 a diff]5t _w2 ! mat]ial _w is blott$ out1 eclips$1 = ! in/ant un?9kable4 ,^! subject-mom5ts are /udi$ to advantage 9 bur/s ( int5se pleasure1 or int5se pa91 9 fits ( engross$ reflection1 especially reflection ^u m5tal facts2 b !y are seldom su/a9$ 9 purity beyond a v %ort int]val2 we are con/antly return+ to ! object-side ( ?+s--to ! _w :]e ext5sion & place h _! be+4 ,?is1 !n1 z x appe>s to me1 is ! only real difficulty ( ! physical & m5tal relation%ip4 ,!re is an alliance ) matt]1 ) ! object1 or ext5d$ _w2 b ! ?+ alli$1 ! m9d prop]1 has itself no ext5sion1 & _c be jo9$ 9 local union4 ,n[1 we h no =m ( language1 no famili> analogy1 suit$ to ?is unique conjunction2 9 comp>ison ) all ord9>y unions1 x is a p>adox or a contradiction4 ,we und]/& union 9 ! s5se ( local connection2 "h is a union :]e local connection is irrelevant1 unsuitable1 contradictory1 = we _c ?9k ( m9d )\t putt+ ourselves out ( ! _w ( place4 ,:51 z 9 pure feel+--pleasure or pa9--we *ange to ! subject attitude f ! object attitude1 we h und]gone a *ange n to be express$ by place2 ! fact is n prop]ly describ$ by ! transition f ! ext]nal to ! int]nal1 = t is /ill a *ange 9 ! region ( ! ext5d$4 ,! only adequate expression is a *ange ( /ate3 a *ange f ! /ate ( ! ext5d$ cognition to a /ate ( unext5d$ cognition4 ,by v>i\s !ologians1 heav5 has be5 spok5 ( u n a place1 b a /ate2 & ?is is ! only phrase t ,i c f9d suitable to describe ! va/1 ?\gh famili> & easy1 transition f ! mat]ial or ext5d$1 to ! immat]ial or unext5d$ side ( ! univ]se ( be+4 ,:51 !re=e1 we talk ( incorporat+ m9d ) bra91 we mu/ be held z speak+ "u an important res]ve or qualification4 ,ass]t+ ! union 9 ! /ronge/ mann]1 we mu/ yet deprive x ( ! almo/ inv9cible association ( union 9 place4 ,an ext5d$ organism is ! condition ( our pass+ into a /ate :]e !re is no ext5sion4 ,a human be+ is an ext5d$ & mat]ial ?+1 atta*$ to :i* is ! p[] ( becom+ alive to feel+ & ?\ght1 ! extreme remove f all t is mat]ial2 a condition ( trance :]e91 :ile x la/s1 ! mat]ial drops out ( view--s mu* s1 t we h n ! p[] to repres5t ! two extremes z ly+ side by side1 z conta9] & conta9$1 or 9 any o!r mode ( local conjunction4 ,! condition ( our exi/+ ?or\ghly 9 ! "o1 is ! mom5t>y eclipse or ext9ction ( ! o!r4 ,! only mode ( union t is n contradictory is ! union ( close succession 9 "t2 or ( position 9 a cont9u$ ?read ( consci\s life4 ,we are entitl$ to say t ! same be+ is1 by alt]nate fits1 object & subject1 "u ext5d$ & "u unext5d$ consci\sness2 & t )\t ! ext5d$ consci\sness ! unext5d$ w\ld n arise4 ,)\t c]ta9 peculi> modes ( ! ext5d$--:at we call a c]ebral organization1 & s on--we c\ld n h ^? times ( trance1 our pleasures1 our pa9s1 & our ideas1 :i* at pres5t we und]go fitfully & alt]nately ) our ext5d$ consci\sness4 ,hav+ ?us call$ att5tion to ! metaphysical difficulty ( assign+ ! relative position ( m9d & matt]1 ,i w n[ /ate briefly :at ,i ?9k ! mode ( deal+ ) m9d 9 correlation ) ! o!r =ces4 ,t !re is a def9ite equival5ce betwe5 m5tal manife/ations & physical =ces1 ! same z betwe5 ! physical =ces !mselves1 is1 ,i ?9k1 con=mable to all ! facts1 al?\gh liable to peculi> difficulties 9 ! way ( decisive pro(3 ,i4 ,! m5tal manife/ations are 9 exact proportion to _! physical supports4 ,if ! doctr9e ( ! ?or\gh-go+ connection ( m9d & body is good = any ?+1 x mu/ g ?is l5g?4 ,!re mu/ be a num]ically-proportion$ rise & fall ( ! two toge!r4 ,i believe t all ! unequivocal facts be> out ?is proportion4 ,take fir/ ! m obvi\s illu/rations4 ,9 ! employm5t ( ext]nal ag5ts1 z w>m? & food1 all w admit t ! s5sation rises exactly z ! /imulant rises1 until a c]ta9 po9t is rea*$1 :5 ! ag5cy *anges its "*2 too great heat de/roy+ ! tissues1 & too mu* food imp$+ dige/ion4 ,!re is1 al?\gh we may n h ! p[] to fix x1 a s5sational equival5t ( heat1 ( food1 ( ex]cise1 ( s\nd1 ( light2 !re is a def9ite *ange ( feel+1 an accession ( pleasure or ( pa91 correspond+ to a rise ( temp]ature 9 ! air ( #aj1 #bj1 or #cj4 ,& s ) reg>d to e o!r ag5t op]at+ ^u ! human s5sibility3 !re is1 9 ea* set ( circum/ances1 a s5sational equival5t ( alcohol1 ( odors1 ( music1 ( spectacle4 ,x is ?is def9ite relation betwe5 outw>d ag5ts & ! human feel+s t r5d]s x possible to discuss human int]e/s f ! objective side1 ! only accessible side4 ,we _c read ! feel+s ( our fell[s2 we m]ely presume t l ag5ts w affect !m all 9 ne>ly ! same way4 ,x is ?us t we measure m5's =tunes & felicity by ! num]ical am\nt ( c]ta9 ag5ts1 z money1 & by ! abs5ce or l[ degree ( c]ta9 o!r ag5ts1 ! causes ( pa9 & ! depressors ( vitality4 ,&1 al?\gh ! e/imate is some:at r\gh1 ?is is n ow+ to ! indef9it5ess ( ! s5sational equival5t1 b to ! complications ( ! human sy/em1 & *iefly to ! n>r[ness ( ! l9e t ev]y:]e divides ! :olesome f ! un:olesome degrees ( all /imulants4 ,let u next repres5t ! equival5ce "u vital or physiological action4 ,! *ief organ conc]n$ is ! bra92 ( :i* we "k t x is a sy/em ( myriads ( connect+ ?reads1 ramify+1 unit+1 & cross+ at innum]able po9ts2 t ^! ?reads are actuat$ or made alive ) a curr5t influ5ce call$ ! n]ve =ce2 t ?is n]ve-=ce is a memb] ( ! gr\p ( correlat+ =ces2 t x is imm$iately d]iv$ f ! *anges 9 ! blood1 & 9 ! la/ resort f oxidation1 or combu/ion1 ( ! mat]ials ( ! food1 ( :i* combu/ion x is a def9ite equival5t4 ,we "k1 fur!r1 t !re c be no feel+1 no volition1 no intellect1 )\t a prop] supply ( blood1 conta9+ bo? oxyg5 & ! mat]ial to be oxidiz$2 t1 z ! blood is ri*] 9 quality 9 reg>d to ^! con/itu5ts1 & m abundant 9 quantity1 ! m5tal processes are m int5se1 m vivid4 ,we "k also t !re are means ( increas+ ! circulation 9 "o organ1 & draw+ x (f f ano!r1 *iefly by call+ ! "o into great] ex]cise1 z :5 we ex]t ! muscles or convey food to ! /oma*2 & t1 :5 m5tal processes are m ?an usually int5sifi$1 ! blood is proportionally drawn to ! bra92 ! oxidiz+ process is !re 9 excess1 ) correspond+ defect & detrim5t 9 o!r organs4 ,9 high m5tal excitem5t1 dige/ion is /opp$2 muscul> vigor is abat$ except 9 ! "o =m ( giv+ v5t to ! feel+s1 ?\ghts1 & purposes2 ! g5]al nutrition langui%es2 &1 if ! /ate 7 long cont9u$ or (t repeat$1 ! physical p[]s1 /rictly s call$1 w\ld rapidly det]iorate4 ,we "k1 on ! o!r extreme1 t sleep is accompani$ by r$uc$ circulation 9 ! bra92 !re is 9 fact a r$uc$ circulation g5]ally2 :ile ( t r$uc$ am\nt m goes to ! nutritive functions ?an to ! c]ebral4 ,9 li/5+ to ,dr4 ,frankl&'s lecture on 8,muscul> ,p[]10 deliv]$ at ! ,royal ,in/itution ( ,london1 ,i notic$ t1 9 acc\nt+ = ! v>i\s items ( exp5diture ( ! food1 he gave 8m5tal "w0 z "o head+1 b decl9$ to make an entry !re9und]4 ,i c imag9e two reasons = ?is res]ve1 ! /atem5t ( :i* w fur!r illu/rate ! g5]al position4 ,9 ! fir/ place1 x might be suppos$ t m9d is a ph5om5on s anomal\s1 unc]ta91 s remote f ! *a9 ( mat]ial cause & effect1 t x is n ev5 to be m5tion$ 9 t connection4 ,to :i* ,i %\ld say1 t m9d is inde$1 z a ph5om5on1 widely diff]5t f ! physical =ces1 b1 nev]!less1 rises & falls 9 /rict num]ical concomitance ) ^!3 s t x /ill ent]s1 if n directly1 at lea/ indirectly1 into ! circle ( ! correlat$ =ces4 ,or1 secondly1 ! lectur] may h held t1 ?\gh a def9ite am\nt ( ! m5tal manife/ations accompanies a def9ite am\nt ( oxidation 9 ! special organs ( m9d1 !re is no means ( r$uc+ ?is to a measure1 ev5 9 an approximate way4 ,to ?is ,i answ]1 t ! ?+ is difficult b n entirely impracticable4 ,!re is a possibility ( giv+1 approximately at lea/1 ! am\nt ( blood circulat+ 9 ! bra91 9 ! ord9>y wak+ /ate2 &1 z dur+ a p]iod ( int5se excitem5t we "k t !re is a g5]al r$uction1 almo/ to p>alysis1 ( ! collective vital functions1 we c\ld n be f> mi/ak5 9 say+ t1 9 t case1 p]haps "o-half or "o-?ird ( all ! oxidation ( ! body 0 exp5d$ 9 keep+ up ! c]ebral fires4 ,x is a v s]i\s drawback 9 any dep>tm5t ( k1 :]e !re are relations ( quantity1 to be unable to r$uce !m to num]ical precision4 ,?is is ! case ) m9d 9 a great degree1 al?\gh n ) x alone2 _m physical qualities are 9 ! same /ate ( unprecise measurem5t4 ,we _c r$uce to numb]s ! /atem5t ( a man's con/itutional vigor1 s z to say h[ mu* he has lo/ by fatigue1 by disease1 by age1 or h[ mu* he has ga9$ by a c]ta9 heal?y regim54 ,und\bt$ly1 h[ev]1 x is 9 m9d t ! difficulties ( atta9+ ! num]ical /atem5t are greate/ if n ne>ly insup]able4 ,:5 we say t "o man is m c\rage\s1 m lov+1 m irascible ?an ano!r1 we apply a scale ( degree1 exi/+ 9 our own m9d1 b s vague t we may apply x diff]5tly at diff]5t times1 :ile we c h>dly communicate x to o!rs exactly z x /&s to ourselves4 ,! consequ5ce is1 t a great m>g9 ( all[ance mu/ always be made 9 ^? /atem5ts2 we c nev] run a close argum5t1 or cont5d = a nice %ade ( di/9ction4 ,betwe5 ! extremes ( timidity & c\rage ( "* ! be/ obs]v] c\ld n ent]ta9 above sev5 or eight v>ieties ( gradation1 :ile two diff]5t p]sons consult+ toge!r c\ld h>dly agree ^u s m9ute a subdivision z t4 ,! phr5ologi/s1 9 _! scale ( qualities1 _h ! advantage ( an ext]nal indication ( size1 b !y mu/ h felt ! uselessness ( graduat+ ?is beyond ! delicacy ( discrim9at+ ! subjective side ( "*2 & _! extreme scale includ$ tw5ty /eps or int]polations4 ,mak+ all[ance = ?is inevitable defect1 ,i w endeavor to pres5t a s]ies ( illu/rations ( ! pr9ciple ( correlation z appli$ to m9d1 9 ! mann] expla9$4 ,i deal n ) m9d directly1 b ) its mat]ial side1 ) ^: activity1 measur$ exactly z we measure ! o!r physical =ces1 true m5tal activity has a def9ite correspond5ce4 ,let u suppose1 !n1 a human be+ ) av]age physical con/itution1 9 respect ( nutritive vigor1 & fairly suppli$ ) food & ) air1 or oxyg54 ,! result ( ! oxidation ( ! food is a def9ite total ( =ce1 :i* may be v>i\sly di/ribut$4 ,! dem& made by ! bra91 to su/a9 ! purely m5tal functions1 may be bel[ av]age1 or above av]age2 !re w be a correspond+1 b inv]se1 v>iation ( ! rema9d] available = ! m /rictly physical processes1 z muscul> p[]1 dige/ive p[]1 animal heat1 & s on4 ,9 ! fir/ case suppos$1 ! case ( a small dem& = m5tal "w & excitem5t1 we look =1 & we f9d1 a bett] physique--great] muscul> p[] & endurance1 m vigor ( dige/ion1 r5d]+ a co>s] food suffici5t = n\ri%m5t1 m resi/ance to excesses ( cold & heat2 9 %ort1 a con/itution adapt$ to physical drudg]y & physical h>d%ip4 ,take1 n[1 ! o!r extreme4 ,let !re be a great dem& = m5tal "w4 ,! oxidation mu/ n[ be disproportionately exp5d$ 9 ! bra92 less is giv5 to ! muscles1 ! /oma*1 ! lungs1 ! sk91 & secret+ organs g5]ally4 ,!re is a r$uction ( ! possible muscul> "w1 & ( ! ability to subsi/ on co>s] food1 & to endure h>d%ip4 ,exp]i5ce confirms ?is inf]5ce2 ! common obs]vation ( mank9d has recogniz$ ! fact--al?\gh 9 a vague1 un/eady =m--t ! head-work] is n equally fitt$ to be a h&-work]4 ,! ma/]1 mi/ress1 or ov]se] has ea* m delicacy ( s5se1 m managem5t1 m res\rce1 ?an ! manual op]atives1 b to ^! belongs ! sup]iority ( muscul> p[] & p]si/5ce4 ,!re is no?+ incompatible ) ! pr9ciple 9 all[+ ! possibility ( comb9+1 "u c]ta9 favorable conditions1 bo? physical & m5tal ex]tion 9 consid]able am\nt4 ,9 fact1 ! pr9ciple tea*es u exactly h[ ! ?+ may be done4 ,improve ! quality & increase ! quantity ( ! food2 increase ! supply ( oxyg5 by heal?y resid5ce2 let ! habitual muscul> ex]tion be su* z to /r5g!n & n impair ! functions2 abate z mu* z possible all excesses & irregul>ities1 bodily & m5tal2 add ! enorm\s economy ( an educat$ disposal ( ! =ces2 & y w develop a high] be+1 a great] aggregate ( p[]4 ,y w !n h m to sp>e = all k9ds ( exp5diture--= ! physico-m5tal1 z well z = ! /rictly physical4 ,:at o!r explanation is ne$$ ( ! milit>y sup]iority ( ! (fic] ov] ! common soldi]8 ( ! g5]al effici5cy ( ! man n\ri%$1 b n en]vat$1 by worldly abundance8 ,x may be possible1 at "s future /age ( sci5tific inquiry1 to compute ! comp>ative am\nt ( oxidation 9 ! bra9 dur+ sev]e m5tal labor4 ,ev5 n[1 f obvi\s facts1 we mu/ pron\nce x to be a v consid]able fraction ( ! entire "w done 9 ! sy/em4 ,! privation ( ! o!r int]e/s dur+ m5tal ex]tion is s app>5t1 s ext5sive1 t if ! ex]tion %\ld happ5 to be long cont9u$1 a lib]al atonem5t has to be made 9 ord] to /ave (f g5]al insolv5cy4 ,m5tal excess c\nts z l>gely z muscul> excess 9 ! div]sion ( p[]2 x w\ld be compet5t to suppose ei!r ! "o or ! o!r r$uc+ ! rema9+ =ces ( ! sy/em to "o-half ( _! prop] am\nt4 ,9 bo? cases1 ! "w ( re/oration mu/ be on ! same simple plan ( r$ress+ ! inequality1 ( all[+ m ?an ! av]age fl[ ( blood to ! impov]i%$ organs1 = a l5g? ( "t correspond+ to ! p]iod :5 _! n\ri%m5t has be5 too small4 ,x is 9 ?is consid]ation t we seem to h ! reasonable1 ,i may say ! ari?metical1 basis ( ! con/itutional treatm5t ( *ronic disease4 ,we repay ! debt to ,nature by all[+ ! weak5$ organ to be bett] n\ri%$ & less tax$1 accord+ to ! degradation x has und]gone by ! opposite l9e ( treatm5t4 ,9 a l>ge class ( diseases we h obvi\sly a species ( insolv5cy1 to be dealt ) accord+ to ! s\nd me?od ( readju/+ ! relations ( exp5diture & income4 ,&1 if su* be ! true !ory1 x seems to foll[ t m$ication is only an inf]ior adjunct4 ,drugs1 ev5 9 _! happie/ application1 c b guide & favor ! re/orative process2 j z ! /irr+ ( a fire may make x burn1 provid$ !re be ! ne$ful fuel4 ,!re is ?us a def9ite1 al?\gh n num]ically-/atable relation1 betwe5 ! total ( ! physico-m5tal =ces & ! total ( ! purely physical processes4 ,! gr& aggregate ( ! oxidation ( ! sy/em includes bo?2 &1 ! m ! =ce tak5 up by "o1 ! less is left to ! o!r4 ,su* is ! /atem5t ( ! correlation ( m9d to ! o!r =ces ( ,nature4 ,we d n deal ) pure m9d--m9d 9 ! ab/ract2 we h no exp]i5ce ( an entity ( t description4 ,we deal ) a comp\nd or two-sid$ ph5om5on--m5tal on "o side1 physical on ! o!r2 !re is a def9ite correspond5ce 9 degree1 al?\gh a diff]5ce ( nature1 betwe5 ! two sides2 & ! physical side is itself 9 full correlation ) ! recogniz$ physical =ces ( ! _w4 ,,ii4 ,!re rema9s ano!r application ( ! doctr9e1 p]haps equally int]e/+ to contemplate1 & m )9 my special l9e ( /udy4 ,i mean ! correlation ( ! m5tal =ces among !mselves 7/ill view$ 9 ! conjo9t arrangem5t74 ,j z we assign limits to m9d z a :ole1 by a ref]5ce to ! grant ( physical exp5diture1 9 oxidation1 etc41 = ! dep>tm5t1 s we mu/ assign limits to ! diff]5t phases or modes ( m5tal "w--?\ght1 feel+1 & s on--accord+ to ! %>e allott$ to ea*2 s t1 :ile ! m9d z a :ole may be /9t$ by ! dem&s ( ! non-m5tal functions1 ea* sep>ate manife/ation is b\nd$ by ! requirem5ts ( ! o!rs4 ,?is is an inevitable consequ5ce ( ! g5]al pr9ciple1 & equally receives ! confirmation ( exp]i5ce4 ,!re is ! same abs5ce ( num]ical precision ( e/imate2 our scale ( quantity c h b few divisions betwe5 ! highe/ & ! l[e/ degrees1 & ^! n well fix$4 ,:at is requir$ = ?is application ( ! pr9ciple is1 to asc]ta9 ! comp>ative co/1 9 ! physical po9t ( view1 ( ! diff]5t functions ( ! m9d4 ,! great divisions ( ! m9d are--feel+1 w1 & ?\ght2 feel+1 se5 9 our pleasures & pa9s2 w1 9 our labors to atta9 ! "o & avoid ! o!r2 ?\ght1 9 our s5sations1 ideas1 recollections1 reason+s1 imag9+s1 & s on4 ,n[1 ! =ces ( ! m9d1 ) _! physical supports1 may be ev5ly or unev5ly di/ribut$ ov] ! ?ree functions4 ,!y may g by pref]5ce ei!r to feel+1 to action1 or to ?9k+2 &1 if m is giv5 to "o1 less mu/ rema9 to ! o!rs1 ! entire quantity be+ limit$4 ,fir/1 z to ! feel+s4 ,e ?rob ( pleasure co/s some?+ to ! physical sy/em2 & two ?robs co/ twice z mu* z "o4 ,if we _c fix a precise equival5t1 x is n because ! relation is n def9ite1 b f ! difficulties ( r$uc+ degrees ( pleasure to a recogniz$ /&>d4 ,( ?is1 h[ev]1 !re c be no reasonable d\bt--namely1 t a l>ge am\nt ( pleasure supposes a correspond+ l>ge exp5diture ( blood & n]ve-tissue1 to ! /9t+1 p]haps1 ( ! active en]gies & ! intellectual processes4 ,x is a matt] ( practical mom5t to asc]ta9 :at pleasures co/ lea/1 = !re are ?rifty & un?rifty modes ( sp5d+ our bra9 & he>t's blood4 ,exp]i5ce probably ju/ifies u 9 say+ t ! n>cotic /imulants are1 9 g5]al1 a m extravagant exp5diture ?an ! /imulation ( food1 society1 & f9e art4 ,"o ( ! safe/ ( delights1 if n v acute1 is ! delight ( ab\nd+ physical vigor2 =1 f ! v supposition1 ! supply to ! bra9 is n su* z to int]f]e ) ! g5]al int]e/s ( ! sy/em4 ,b ! !ory ( pleasure is incomplete )\t ! !ory ( pa94 ,z a rule1 pa9 is a m co/ly exp]i5ce ?an pleasure1 al?\gh sometimes economical z a *eck to ! sp5d?rift pleasures4 ,pa9 is physically accompani$ by an excess ( blood 9 ! bra91 f at lea/ two causes--extreme int5sity ( n]v\s action1 & conflict+ curr5ts1 bo? be+ s\rces ( wa/e4 ,! sleeplessness ( ! pa9$ condition means t ! circulation is nev] all[$ to subside f ! bra92 ! irritation ma9ta9s en]getic curr5ts1 :i* br+ ! blood copi\sly to ! p>ts affect$4 ,!re is a possibility ( excitem5t1 ( consid]able am\nt1 )\t ei!r pleasure or pa92 ! co/ "h is simply z ! excitem5t3 m]e surprises may be ( ?is nature4 ,su* excitem5t has no value1 except intellectually2 x may deta9 ! ?\ghts1 & impress ! memory1 b x is n a f9al end ( our be+1 z pleasure is2 & x does n wa/e p[] to ! ext5t t pa9 does4 ,! ideally be/ condition is a mod]ate surplus ( pleasure--a g5tle gl[1 n ris+ into brilliancy or int5sity1 except at consid]able int]vals 7say a small portion ( e day71 fall+ d[n frequ5tly to indiff]5ce1 b seldom s9k+ into pa94 ,att5dant on /rong feel+1 especially 9 con/itutions "y or robu/1 !re is usually a great am\nt ( m]e bodily vehem5ce1 z ge/iculation1 play ( c\nt5ance1 ( voice1 & s on4 ,?is c\nts z muscul> "w1 & is an addition to ! bra9-"w4 ,prop]ly speak+1 ! c]ebral curr5ts dis*>ge !mselves 9 movem5ts1 & are modifi$ accord+ to ! scope giv5 to ^? movem5ts4 ,resi/ance to ! movem5ts is liable to increase ! consci\s activity ( ! bra91 al?\gh a cont9u+ resi/ance may suppress ! entire wave4 ,next z to ! w1 or our volunt>y labors & pursuits = ! great ends ( obta9+ pleasure & w>d+ (f pa94 ,?is "p ( our sy/em is a comp\nd exp]i5ce ( feel+ & movem5t2 ! prop]ly m5tal fact be+ includ$ "u feel+--t is1 pleasure & pa91 pres5t or imag9$4 ,:5 our volunt>y endeavors are successful1 a di/9ct ?rob ( pleasure is ! result1 :i* c\nts among our valuable enjoym5ts3 :5 !y fail1 a pa9ful & depress+ /ate ensues4 ,! m complicat$ op]ations ( ! w1 z 9 adju/+ _m opposite int]e/s1 br+ 9 ! elem5t ( conflict1 :i* is always pa9ful & wa/+4 ,two /rong /imulants po9t+ opposite ways1 z :5 a mis] has to pay a high fee to ! surgeon t saves 8 eyesight1 occasion a fi]ce /ruggle & sev]e draft ^u ! physical supports ( ! feel+s4 ,al?\gh ! processes ( feel+ all involve a manife/1 & x may be a s]i\s1 exp5diture ( physical p[]1 :i* ( c\rse is lo/ to ! purely physical functions2 & al?\gh ! extreme degrees ( pleasure1 ( pa91 or ( neutral excitem5t1 mu/ be adv]se to ! g5]al vigor2 yet ! presumption is1 t we c af=d a c]ta9 mod]ate %>e ( all ^! )\t too great inroads on ! o!r int]e/s4 ,x is ! ?9k+ or intellectual "p ( u t involves ! heavie/ item ( exp5diture 9 ! physico-m5tal dep>tm5t4 ,any ?+ l a great or g5]al cultivation ( ! p[]s ( ?\ght1 or any occupation t sev]ely & cont9u\sly br+s !m into play1 w induce su* a prepond]ance ( c]ebral activity1 9 oxidation & 9 n]ve-curr5ts1 z to di/urb ! balance ( life1 & to require special arrangem5ts = r$eem+ t di/urbance4 ,?is is fully v]ifi$ by all we "k ( ! t5d5cy ( intellectual application to exhau/ ! physical p[]s1 & to br+ on e>ly decay4 ,a c>eful analysis ( ! op]ations ( ! intellect enables u to di/+ui% ! k9d ( ex]cises t involve ! greate/ exp5diture1 f ! ext5t & ! int5sity ( ! c]ebral occupation4 ,i c b make a rapid selection ( lead+ po9ts3 ,fir/4 ,! m]e ex]cise ( ! s5ses1 9 ! way ( att5tion1 ) a view to wat*1 to discrim9ate1 to id5tify1 belongs to ! intellectual function1 & exhau/s ! p[]s accord+ z x is long cont9u$1 & accord+ to ! delicacy ( ! op]ation2 ! mean+ ( delicacy be+ t an exagg]at$ activity ( ! organ is ne$$ to make ! requir$ disc]nm5t4 ,to be all day on ! qui vive = "s v slight & b>ely p]ceptible indications to ! eye or ! e>1 z 9 cat*+ an indi/9ct speak]1 is an exhau/+ labor ( att5tion4 ,secondly4 ,! "w ( acquisition is necess>ily a process ( great n]v\s exp5diture4 ,un9t5tional imitation co/s lea/1 because !re is no =c+ ( reluctant att5tion4 ,b a c\rse ( ext5sive & v>i\s acquisitions _c be ma9ta9$ )\t a l>ge supply ( blood to cem5t all ! multif>i\s connections ( ! n]ve-fibres1 con/itut+ ! physical side ( acquisition4 ,an abat$ support ( o!r m5tal functions1 z well z ( ! purely physical functions1 mu/ accompany a life devot$ to m5tal improvem5t1 :e!r arts1 languages1 sci5ces1 moral re/ra9ts1 or o!r culture4 ,( special acquisitions1 languages are ! mo/ app>5tly volum9\s2 b ! memory = visible or pictorial aspects1 if v high1 z 9 ! pa9t] & ! picturesque poet1 makes a prodigi\s dem& ^u ! pla/ic comb9ations ( ! bra94 ,! acquisition ( sci5ce is sev]e1 r ?an multif>i\s2 x glories 9 compreh5d+ mu* 9 little1 b t little is made up ( pa9ful ab/ract elem5ts1 e "o ( :i*1 9 ! la/ resort1 mu/ h at its beck a ho/ ( explanatory p>ticul>s3 s t1 aft] all1 ! burd5 lies 9 ! multitude4 ,if sci5ce is easy to a select numb] ( m9ds1 x is because !re is a l>ge spontane\s det]m9ation ( =ce to ! c]ebral elem5ts t support x2 :i* =ce is suppli$ by ! limit$ common fund1 & leaves s mu* ! less = o!r uses4 ,if we adv]t to ! moral acquisitions & habits 9 a well-regulat$ m9d1 we mu/ admit ! ne$ ( a l>ge exp5diture to build up ! fabric4 ,! c>efully-pois$ e/imate ( good & evil = self1 ! ev]-pres5t s5se ( ! int]e/s ( o!rs1 & ! ready ob$i5ce to all ! special ord9ances t make up ! morality ( ! "t1 h[ev] truly express$ 9 t]ms ( high & ab/ract spirituality1 h _! c\nt]p>t 9 ! physical organism2 !y h us$ up a l>ge & def9ite am\nt ( nutrim5t1 &1 _h !y be5 less develop$1 !re w\ld h be5 a ga9 ( p[] to "s o!r dep>tm5t1 m5tal or physical4 ,refra9+ f fur!r detail on ?is head1 ,i close ! illu/ration by a brief ref]5ce to "o o!r aspect ( m5tal exp5diture1 namely1 ! dep>tm5t ( intellectual production1 execution1 or creativ5ess1 to :i* 9 ! end our acquir$ p[]s are m9i/]ial4 ,( c\rse1 ! great] ! m]e cont9uance or am\nt ( intellectual labor 9 bus9ess1 speculation1 f9e art1 or any ?+ else1 ! great] ! dem& on ! physique4 ,b am\nt is n all4 ,!re are notori\s diff]5ces ( sev]ity or labori\sness1 :i*1 :5 closely exam9$1 are summ$ up 9 "o compreh5sive /atem5t--namely1 ! numb]1 ! v>iety1 & ! conflict+ nature ( ! conditions t h to be fulfill$4 ,by ?is we expla9 ! difficulty ( "w1 ! toil ( inv5tion1 ! h>assm5t ( adaptation1 ! worry ( lead]%ip1 ! responsibility ( high (fice1 ! sev]ity ( a l(ty ideal1 ! di/raction ( num]\s sympa?ies1 ! m]itori\sness ( s\nd judgm5t1 ! ardu\sness ( any great virtue4 ,! physical facts und]ly+ ! m5tal fact are a wide-spread agitation ( ! c]ebral curr5ts1 a tumultu\s conflict1 a consumption ( en]gy4 ,x is ?is compliance ) num]\s & oppos+ conditions t obta9s ! mo/ scanty ju/ice 9 our appreciation ( "*4 ,! unkn[n am\nt ( pa9ful suppression t a cauti\s ?9k]1 a c>eful writ]1 or an arti/ ( f9e ta/e1 has gone ?r\gh1 repres5ts a great physico-m5tal exp5diture4 ,! reg>d to evid5ce is a heavy drag on ! w+s ( speculative d>+4 ,! great] ! numb] ( int]e/s t a political s*em] c ?r[ ov]bo>d1 ! easi] 8 "w ( con/ruction4 ,! abs5ce ( re/ra9ts--( sev]e conditions--9 f9e art1 all[s a flu% & ebulli5ce1 an opul5ce ( production1 t is (t5 call$ ! highe/ g5ius4 ,! ,%akespe>ean pr(usion ( images w\ld h be5 r$uc$ to "o-half1 if n less1 by ! self-impos$ re/ra9ts ( ,pope1 ,gray1 or ,t5nyson4 ,s1 reckless ass]tion is fuel to eloqu5ce4 ,a man ( ord9>y fairness ( m9d w\ld be no mat* = ! wit & epigram ( ,swift4 ,& aga94 ,! incompatibility ( div]se attributes1 ev5 9 m9ds ( ! l>ge/ compass 7:i* supposes equally l>ge physical res\rces71 belongs to ! same fundam5tal law4 ,a great m9d may be great 9 _m ?+s1 because ! same k9d ( p[] may h num]\s applications4 ,! sci5tific m9d ( a high ord] is also ! practical m9d2 x is ! ess5ce ( reason 9 e mode ( its manife/ation--! true philosoph] 9 conduct z well z 9 k4 ,on su* a m9d also1 a c]ta9 am\nt ( arti/ic culture may be sup]9duc$2 its p[]s ( acquisition may be ext5d$ s f>4 ,b ! spontane\s1 exub]ant1 imag9ative fl[1 ! arti/ic nature at ! core1 nev] 01 _c be1 includ$ 9 ! same individual4 ,ari/otle c\ld n be also a tragic poet2 nor ,newton a ?ird-rate portrait-pa9t]4 ,! co/ ( "o ( ! two modes ( intellectual greatness is all t c be borne by ! mo/ l>gely-end[$ p]sonality2 any appe>ances to ! contr>y are holl[ & delusive4 ,o!r in/ances c\ld be giv54 ,great activity & great s5sibility are extreme phases1 ea* us+ a l>ge am\nt ( p[]1 & !re=e sc>cely to be c\pl$ 9 ! same sy/em4 ,! active1 en]getic man1 lov+ activity = its own sake1 mov+ 9 e direction1 wants ! delicate circumspection ( ano!r man :o does n love activity = its own sake1 b is en]getic only at ! spur ( 8 special ends4 ,& once m4 ,great intellect z a :ole is n readily unit$ ) a l>ge emotional nature4 ,! incompatibility is be/ se5 by inquir+ :e!r m5 ( ov]fl[+ sociability are deep & orig9al ?9k]s1 great discov]]s1 accurate inquir]s1 great organiz]s 9 affairs2 or :e!r _! greatness is n limit$ to ! sph]es :]e feel+ p]=ms a "p--poetry1 eloqu5ce1 & social asc5d5cy4 ,,! ,,end4 ,,footnotes3 #ah ,= ! full] elaboration ( ! po9t "h ref]r$ to1 see ,*apt] ,,vii41 ,pr(essor ,ba9's 8,m9d & ,body0--an e>li] volume 9 ! pres5t s]ies4 ,,index4 ,absorb$ heat *ang$ into *emical sep>ation1 #aad4 into actual visible en]gy1 #aje4 into light & heat1 #aag4 ,acquisition1 #bcb4 ,act9ic rays1 #abi4 ,action & reaction equal & opposite1 #h4 ,aff9ity1 *emical1 #ec4 ,air & wat] 9 motion1 #adg4 ,album9oids1 #agg1 #ahc4 ,amb]1 #fa4 ,ampre1 #ge4 ,amyloids1 #agg1 #ahc4 ,anci5ts1 _! ideas n prolific1 #ace4 ,&rews1 #ada4 ,animal heat1 #bjg4 ,animals1 h[ !y live1 #ahh4 ,animals & inanimate ma*9es1 #afe4 ,ari/otle on a m$ium1 #acd4 on m9d & body1 #bjg4 ,atmosph]ic circulation1 #aji4 ,atomic =ces & heat1 #eh4 ,atomic or *emical sep>ation1 #hj4 ,atoms & molecules1 #ea4 ,att5tion1 #bcb4 ,attraction1 molecul>1 #eb4 mutual1 ( atoms1 #ed4 & repulsion ( magnets1 #ge4 ( electric curr5ts1 #ge4 ,bacon1 #acc1 #acg4 ,batt]y ( ,grove1 #gj4 ,budd+1 #ahj4 ,caloric1 #ch4 ,c>nivora1 #ahi4 ,*emical aff9ity1 #ec4 & electrical attraction1 #fd4 & heat1 #eh4 ,*emical comb9ation produc+ heat1 #aai4 ,*emical in/ability1 #aef4 ,*emical sep>ation conv]t$ into electrical sep>ation1 #abb4 into electricity 9 motion1 #abc4 ,*lorophyll1 #agg4 ,*rysalis1 #ahg4 ,circulation ( ! atmosph]e1 #aji4 ,clausius1 #ada4 ,cohesion1 =ce (1 #ea4 ,cold app>5tly produc$ by ! electric curr5t1 #abf4 ,conduction ( electricity1 #fa4 ,cons]vation1 laws (1 #hb4 !ory (1 #adj4 ,crossb[ & wat*-spr+1 #be4 ,curr5t1 ! electric1 #fi4 & magnetism1 #gb4 heat+ effect (1 #gc4 *emical effect (1 #gd4 ,curr5ts1 electric1 attraction & repulsion (1 #gd4 induction (1 #ge4 ,dalton1 #acc4 ,davy1 ,sir ,humphrey1 #ch1 #acg4 ,democritus on atoms1 #acc4 ,desc>tes1 #acf4 ,dia/ase1 #ahd4 ,disease-g]ms1 #c4 ,dissipation ( en]gy1 #ada4 ,dissociation1 #aae4 ,egg1 developm5t ( !1 #ahf4 ,electric curr5t1 #fi4 & magnetism1 #gb4 heat+ effect (1 #gc4 *emical effect (1 #gd4 induction1 #fe4 ,electrical attraction & *emical aff9ity1 #fd4 ,electrical sep>ation1 #ha4 :5 produc$1 #fd4 transmut$ into visible motion1 #abd4 into electric curr5t1 #abd4 ,electro-magnetism1 #gb4 ,ela/ic =ces1 #ej4 ,electricity1 #fj4 vitre\s & res9\s1 #fc4 negative & positive1 #fc4 !ory (1 #fc4 9 motion1 #ha4 transmut$ into visible motion1 #abd4 into heat1 #abe4 into *emical sep>ation1 #abg4 ,encke's comet1 #if4 ,en]gies1 li/ (1 #gh-hb4 natural1 & _! s\rces1 #adc4 ,en]gy1 mean+ (1 #a-bb4 ( bodies 9 motion proportional to _! weight or mass1 #ad4 proportional to ! squ>e ( ! velocity1 #ai4 ( visible motion1 its transmutation1 #hg4 visible1 trans=m$ into absorb$ heat1 #hh4 dissipation (1 #ada4 transmutations (1 #bg4 v>ies z ! squ>e ( ! velocity1 #ae4 ( motion1 #bd4 trans=m$ into electrical sep>ation1 #ih4 ( position1 a sort ( capital1 #bf4 ,equilibrium1 #aed4 ,etiolation1 #ahj4 ,f]m5tation1 #ahc4 ,food1 #ade4 ,=ce1 vital1 :5ce d]iv$1 #aga4 physical1 #aid4 *emical1 #aid4 ( *emical aff9ity1 #ec4 ( cohesion1 #ea4 ,=ce1 me*anical or mol>1 #bje4 molecul>1 #bje4 ,friction1 #ce4 ,heat1 absorb$1 *ang$ into *emical sep>ation1 #aad4 into electrical sep>ation1 #aae4 into electricity 9 motion1 #aaf4 ,heat-units ( diff]5t sub/ances1 #aai4 ,heat-motion1 #hj4 ,heat-eng9es1 _! ess5tial conditions1 #ajg4 ,helmholtz1 #ada4 ,h]aclitus on en]gy1 #acc4 ,h]bivora1 #aia4 ,het]og5eity ess5tial 9 electrical developm5t1 #fd4 ,huygh5s1 #acg4 ,hydraulic press1 #cb4 ,incl9$ plane1 #bh4 ,incubation1 #ahf4 ,individuals1 our ignorance (1 #a4 ,induction1 electric1 #fe4 ( electric curr5ts1 #ge4 ,in/ability1 me*anical1 #aee4 *emical1 #aef4 ,intellectual labor1 #bcd4 ,j\le1 #acg1 #adj1 #ada4 ,j\le's exp]im5ts on "w & heat1 #dd4 ,kilogrammetre1 #af4 ,l>va1 #ahg4 ,lat5t heat1 #eg4 ,laws ( cons]vation1 #hb4 ,life dep5ds on ! sun1 #afe4 ,light1 a p]petual1 impossible1 #adi4 ,lime1 c>bonate1 easily decompos$1 #eh4 ,li/ ( en]gies1 #gh-hb4 ,ma*9es1 _! true function1 #cc4 animat$ & inanimate1 #aeg4 ,magnets1 atta*m5t & repulsion (1 #ge4 ,maxwell1 #ada4 ,mayor1 #adj4 ,me*anical en]gy *ang$ into heat1 #bc4 equival5t ( heat1 #dc4 =ce1 #bje4 in/ability1 #aee4 ,m5tal =ces1 mutual correlations (1 #bbg-bcf4 ,m9d1 its correlations to natural =ces1 #bah-bbg4 & body1 #bjg1 #baa4 ,mol> =ce1 #bje4 ,molecul> attraction & heat1 #ee4 sep>ation1 #hj4 ,molecules1 ultimate1 ( matt]1 #e4 _! motions1 #g4 & atoms1 #ea4 ,motion *ang$ into an electric curr5t1 #ii4 ,muscul> p[]1 #bjg4 ,n>cotic /imulants1 #bbi4 ,negative & positive electricity1 #fc4 ,n]ve p[]1 #bjg4 ,newton1 #acf1 #acg4 ,non-conductors ( electricity1 #fa4 ,p]cussion1 #cf4 ,p]petual motion1 #aci4 ,physical =ce1 #aid4 ,plants gr[+ at night1 #aha4 ,positive & negative electricity1 #fc4 ,protoplasm1 #agg4 ,pulleys1 _! function1 #cj4 ,radiant en]gy1 #ha4 conv]t$ into absorb$ heat1 #abc4 promot+ *emical sep>ation1 #abc4 ,rank9e1 #ada4 ,res9\s & vitre\s electricity1 #fc4 ,rotation ( e>? ret>d$1 #ie4 ,rum=d1 #ci1 #acg4 ,silv] oxide readily decompos$1 #eh4 ,sol> rays1 decomposition by1 #ei4 ,sulphur1 #adf4 ,sun--a s\rce ( high-temp]ature heat1 #adh4 ,sun's heat1 orig9 (1 #aej4 spots1 auroras1 & cyclones correlat$1 #ih4 ,tait1 #ada4 ,temp]ature ( dissociation1 #aae4 ,!rmo-electricity1 #aaf4 ,!rmopile1 #aag4 ,?omas ,aqu9as1 #bji4 ,?omson1 ,william & ,james1 #adj4 ,tides1 #adf4 ,tissues1 decay (1 #afd4 ,univ]se1 its probable fate1 #aeb4 ,units ( heat & "w1 #df4 ,vegetation1 #agf4 ,velocity & en]gy1 relation betwe51 #af4 ,virtual velocities1 #cd4 pr9ciple (1 its hi/ory1 #acg4 ,vital =ce1 :5ce d]iv$1 #aga4 ,vitality1 #aid4 ,vitre\s & res9\s electricity1 #fc4 ,voltaic curr5t1 #fi4 & magnetism1 #gb4 heat+ effect (1 #gc4 *emical effect (1 #gd4 ,wat] at high level1 #bd4 ,watt1 #ach4 ,wild's electro-magnetic ma*9e1 #ajc4 ,w1 #aid4 ,"w1 def9ition (1 #ae4 unit (1 #ae4 rise ( true conceptions reg>d+1 #ach4 ,yea/-plant1 #ahe4 ,,! ,,end4 ,transcrib]'s ,notes ,errors 9 punctuation h be5 fix$4 ,page #fj3 8het]og5\s bodies0 *ang$ to 8het]og5e\s bodies0 ,page #hj3 8,analag\s to ?is0 *ang$ to 8,analog\s to ?is0 ,page #hb3 8e!rial m$ium0 *ang$ to 8e!real m$ium0 ,page #aeg3 8)\t occcasion$0 *ang$ to 8)\t occasion$0