,sci5ce ,prim]s4 ,,introductory4 ,,by ,,pr(essor ,,huxley1 ,f4,r4,s4 ,toronto3 ,,canada ,,publi%+ ,,co41 7,,limit$47 ,ent]$ accord+ to ! ,act ( ! ,p>liam5t ( ,canada1 9 ! ye> ,"o ,?\s& ,eight ,hundr$ & ,eighty-"o by ,,macmillan ,,co41 ,,london1 9 ! ,(fice ( ! ,m9i/] ( ,agriculture4 ,,table ,,( ,,cont5ts4 ,,"p4 ,,sect4 ,i4 ,,nature ,,& ,,sci5ce4 ,,page #a4 ,s5sations & ,?+s #e #b4 ,causes & ,effects #e #c4 ,! reason ,:y4 ,explanation #f #d4 ,prop]ties & ,p[]s #g #e4 ,artificial & ,natural ,objects4 ,nature #h #f4 ,artificial ,?+s are only ,natural ,?+s %ap$ & br\ght toge!r or sep>at$ by ,m5 #h #g4 ,_m ,objects & ,*a9s ( ,causes & ,effects 9 ,nature are out ( our rea* #aj #h4 ,! ,ord] ( ,nature3 no?+ happ5s by ,accid5t1 & !re is no su* ?+ z ,*ance #aj #i4 ,laws ( ,nature2 ,laws are n ,causes #ab #aj4 ,k ( ,nature is ! ,guide ( ,practical ,conduct #ad #aa4 ,sci5ce3 ,! ,k ( ! ,laws ( ,nature obta9$ by ,obs]vation1 ,exp]im5t1 & ,reason+ #af ,,ii4 ,,mat]ial ,,objects4--7,a47 ,,m9]al ,,bodies4 #ab4 ,! ,natural ,object ,wat] #ai #ac4 ,a ,tumbl] ( ,wat] #bj #ad4 ,wat] occupies ,space2 x (f]s ,resi/ance2 x has ,weight2 & is able to transf] ,motion :i* x has acquir$2 x is !re=e a =m ( ,matt] #bj #ae4 ,wat] is a liquid #ba #af4 ,wat] is almo/ incompressible #bb #ag4 ,! mean+ ( ,weight #bd #ah4 ,gravity & ,gravitation #be #ai4 ,! cause ( ,weight3 ,attraction3 ,=ce #bg #bj4 ,! ,weight ( ,wat] is ,proportion$ to its ,bulk #bh #ba4 ,! ,measur+ ( ,weights4 ,! ,balance #bi #bb4 ,! ,weight ( ! same ,bulk or ,volume ( ,wat] is ,con/ant "u ! same conditions4 ,mass4 ,d5sity #cj #bc4 ,equal ,volumes ( ,diff]5t ,?+s "u ! same circum/ances1 h ,diff]5t ,weights3 ! ,d5sity ( ,diff]5t ,bodies is ,diff]5t #cb #bd4 ,! ,mean+ ( ,heavy & ,light--,specific ,gravity #cc #be4 ,?+s ( great] ,specific ,gravity ?an ,wat] s9k 9 ,wat]2 ,?+s ( less ,specific ,gravity float #cd #bf4 ,a ,body :i* ,floats 9 ,wat] always occupies z mu* ,space b5ea? ! level ( ! ,surface ( ! ,wat] z is equal to ! ,volume ( ,wat] :i* weighs z mu* z t ,body2 9 o!r words1 x displaces its own ,weight ( ,wat] #cf #bg4 ,wat] ,presses 9 all ,directions #cg #bh4 ,! ,transf]5ce ( ,motion by ,mov+ ,wat]3 ! ,mom5tum ( ,mov+ ,wat] #dj #bi4 ,! ,en]gy ( ,mov+ ,wat] #dc #cj4 ,! ,prop]ties ( ,wat] are ,con/ant #dg #ca4 ,increase ( ,heat at fir/ causes ,wat] to ,increase 9 ,volume #dh #cb4 ,increase ( ,heat at l5g? causes ,wat] to become ,/eam #ej #cc4 ,! tak+ away ( ,heat f ,/eam causes ! ,/eam to *ange into ,hot ,wat] #ea #cd4 ,:5 ,wat] is *ang$ into ,/eam1 its ,volume becomes ab\t #a1gjj times great] ?an x 0 at fir/ #ea #ce4 ,gases or ,ela/ic ,fluids4 ,air #eb #cf4 ,/eam is an ,ela/ic ,fluid or ,gas #ed #cg4 ,gases & ,vap\rs #ee #ch4 ,! ,evaporation ( ,wat] at ord9>y ,temp]atures #ef #ci4 ,:5 ,hot ,wat] is cool$1 x ,contracts to beg9 )1 b aft] a "t ,exp&s #eg #dj4 ,wat] cool$ /ill fur!r becomes ! transp>5t brittle solid ,ice #eh #da4 ,ice has less ,specific ,gravity ?an ! ,wat] f :i* x 0 =m$ #ei #db4 ,ho> ,fro/ is ! ,gase\s ,wat] :i* exi/s 9 ! ,atmosph]e1 cond5s$ & conv]t$ into ,ice ,cry/als #fj #dc4 ,:5 ,ice is w>m$ x beg9s to *ange back into ,wat] z soon z ! ,temp]ature rea*es #cb #fa #dd4 ,ice ! solid1 ,wat] ! liquid1 & ,/eam ! gas1 are ?ree /ates ( "o natural object2 ! ,condition ( ea* ,/ate be+ a c]ta9 ,am\nt ( ,heat #fb #de4 ,! ,ph5om5a ( ,heat are ! ,effects ( a rapid ,motion ( ! ,p>ticles ( ,matt] #fc #df4 ,! ,/ructure ( ,wat] #fe #dg4 ,suppositions or ,hypo!ses2 _! ,uses & _! ,value #fg #dh4 ,! ,hypo!sis t ,wat] is compos$ ( ,sep>ate ,p>ticles 7,molecules7 #fh #di4 ,all ,matt] is probably made up ei!r ( ,molecules or ( ,atoms #gj #ej4 ,elem5t>y ,bodies are nei!r de/roy$ nor is _! ,quantity increas$ 9 ,nature #gb #ea4 ,simple ,mixture #gc #eb4 ,mixture foll[$ by ,increase ( ,d5sity2 ,alcohol & ,wat] #gd #ec4 ,solution2 ,wat] ,dissolves ,salt #gf #ed4 ,quicklime & ,wat]3 ,pla/] ( ,p>is & ,wat]3 ,comb9ation #gi #ee4 ,m9]al bodies may take on def9ite %apes & gr[1 or increase 9 size1 by ! addition ( l p>ts #hb 7,b47 ,,liv+ ,,bodies4 #ef4 ,! ,:eat ,plant & ! sub/ances ( :i* x is compos$ #hc #eg4 ,! common ,f[l & ! ,sub/ances ( :i* x is ,compos$ #he #eh4 ,c]ta9 ,con/itu5ts ( ! ,body are v simil> 9 ! ,:eat ,plant & 9 ! ,f[l #hf #ei4 ,proteid ,sub/ances are met ) 9 ,nature only 9 ,animals & ,plants2 & ,animals & ,plants always conta9 ,proteids #hg #fj4 ,:at is meant by ! ^w ,liv+8 #hh #fa4 ,! ,liv+ ,plant increases 9 ,size1 by add+ to ! ,sub/ances :i* compose its ,body1 l ,sub/ances2 ^!1 h[ev]1 are n d]iv$ f )\t1 b are manufactur$ )9 ! ,body ( ! ,plant f simpl] ,mat]ials #hh #fb4 ,! ,liv+ ,plant1 aft] x has gr[n up1 deta*es "p ( its ,sub/ance1 :i* has ! ,p[] ( develop+ into a simil> ,plant1 z a ,se$ #ij #fc4 ,! ,liv+ ,animal increases 9 ,size by add+ to ! ,sub/ances :i* compose its ,body1 l ,sub/ances2 ^!1 h[ev]1 are *iefly d]iv$ directly f o!r ,animals or f ,plants #ij #fd4 ,! liv+ ,animal1 aft] x has gr[n up1 deta*es "p ( its ,sub/ance1 :i* has ! ,p[] ( gr[+ into a simil> ,animal1 z an ,egg #ia #fe4 ,liv+ ,bodies diff] f ,m9]al ,bodies 9 _! ,ess5tial ,composition1 9 ! mann] ( _! ,gr[?1 & 9 ! fact t !y are reproduc$ by ,g]ms #ia ,,iii4 ,,immat]ial ,,objects4 #ff4 ,m5tal ,ph5om5a #ib #fg4 ,! ord] ( ,m5tal ,ph5om5a3 ,psy*ology #ic ,,sci5ce ,,prim]s4 ,,introductory4 ,i4 ,,nature ,,& ,,sci5ce4 #a4 ,s5sations & ,?+s4 ,all ! "t t we are awake we are le>n+ by means ( our s5ses some?+ ab\t ! _w 9 :i* we live & ( :i* we =m a "p2 we are con/antly aw>e ( feel+1 or he>+1 or smell+1 &1 unless we happ5 to be 9 ! d>k1 ( see+2 at int]vals we ta/e4 ,we call ! in=mation ?us obta9$ s5sation4 ,:5 we h any ( ^! s5sations we commonly say t we feel1 or he>1 or smell1 or see1 or ta/e1 some?+4 ,a c]ta9 sc5t makes u say we smell onions2 a c]ta9 flav\r1 t we ta/e apples2 a c]ta9 s\nd1 t we he> a c>riage2 a c]ta9 appe>ance be=e our eyes1 t we see a tree2 & we call t :i* we ?us p]ceive by ! aid ( our s5ses a ?+ or an object4 #b4 ,causes & ,effects4 ,moreov]1 we say ( all ^! ?+s1 or objects1 t !y are ! causes ( ! s5sations 9 "q1 & t ! s5sations are ! effects ( ^! causes4 ,= example1 if we he> a c]ta9 s\nd1 we say x is caus$ by a c>riage go+ along ! road1 or t x is ! effect1 or ! consequ5ce1 ( a c>riage pass+ along4 ,if !re is a /rong smell ( burn+1 we believe x to be ! effect ( some?+ on fire1 & look ab\t anxi\sly = ! cause ( ! smell4 ,if we see a tree1 we believe t !re is a ?+ or object1 :i* is ! cause ( t appe>ance 9 our field ( view4 #c4 ,! reason ,:y4 ,explanation4 ,9 ! case ( ! smell ( burn+1 :5 we f9d on look+ ab\t1 t some?+ actually is on fire1 we say indiff]5tly ei!r t we h f\nd out ! cause ( ! smell1 or t we "k ! reason :y we p]ceive t smell2 or t we h expla9$ x4 ,s t to "k ! reason :y ( any?+1 or to expla9 x1 is to "k ! cause ( x4 ,b t :i* is ! cause ( "o ?+ is ! effect ( ano!r4 ,?us1 suppose we f9d "s sm\ld]+ /raw to be ! cause ( ! smell ( burn+1 we imm$iately ask :at set x on fire1 or :at is ! cause ( its burn+8 ,p]haps we f9d t a light$ lucif] mat* has be5 ?r[n into ! /raw1 & !n we say t ! light$ mat* 0 ! cause ( ! fire4 ,b a lucif] mat* w\ld n be 9 t place unless "s p]son _h put x !re4 ,t is to say1 ! pres5ce ( ! lucif] mat* is an effect produc$ by somebody z cause4 ,s we ask :y did any "o put ! mat* !re8 ,0 x done c>elessly1 or did ! p]son :o put x !re int5d to d s8 ,& if s1 :at 0 8 motive1 or ! cause :i* l$ him to d su* a ?+8 ,& :at 0 ! reason = 8 hav+ su* a motive8 ,x is pla9 t !re is no end to ! que/ions1 "o aris+ out ( ! o!r1 t might be ask$ 9 ?is fa%ion4 ,?us we believe t ev]y?+ is ! effect ( some?+ :i* prec$$ x z its cause1 & t ?is cause is ! effect ( some?+ else1 & s on1 ?r\gh a *a9 ( causes & effects :i* goes back z f> z we *oose to foll[ x4 ,any?+ is said to be expla9$ z soon z we h discov]$ its cause1 or ! reason :y x exi/s2 ! explanation is full]1 if we c f9d out ! cause ( t cause2 & ! fur!r we c trace ! *a9 ( causes & effects1 ! m satisfactory is ! explanation4 ,b no explanation ( any?+ c be complete1 because human k1 at its be/1 goes b a v little way back t[>ds ! beg9n+ ( ?+s4 #d4 ,prop]ties & ,p[]s4 ,:5 a ?+ is f\nd always to cause a p>ticul> effect1 we call t effect sometimes a prop]ty1 sometimes a p[] ( ! ?+4 ,?us ! odor ( onions is said to be a prop]ty ( onions1 because onions always cause t p>ticul> s5sation ( smell to arise1 :5 !y are br\ght ne> ! nose2 lead is said to h ! prop]ty ( heav9ess1 because x always causes u to h ! feel+ ( weight :5 we h&le x2 a /ream is said to h ! p[] to turn a wat]-:eel1 because x causes ! wat]-:eel to turn2 & a v5om\s snake is said to h ! p[] to kill a man1 because its bite may cause a man to die4 ,prop]ties & p[]s1 !n1 are c]ta9 effects caus$ by ! ?+s :i* are said to possess !m4 #e4 ,artificial & ,natural ,objects4 ,nature4 ,a great _m ( ! ?+s br\ght to our k by our s5ses1 su* z h\ses & furniture1 c>riages & ma*9es1 are t]m$ artificial ?+s or objects1 because !y h be5 %ap$ by ! art ( man2 inde$1 !y are g5]ally said to be made by man4 ,b a f> great] numb] ( ?+s owe no?+ to ! h& ( man1 & w\ld be j :at !y are if mank9d did n exi/1--su* z ! sky & ! cl\ds2 ! sun1 moon & />s2 ! sea ) its rocks & %+ly or s&y %ores2 ! hills & dales ( ! l&2 & all wild plants & animals4 ,?+s ( ?is k9d are t]m$ natural objects1 & to ! :ole ( !m we give ! "n ( ,nature4 #f4 ,artificial ,?+s are only ,natural ,?+s %ap$ & br\ght toge!r or sep>at$ by ,m54 ,al?\gh ?is di/9ction betwe5 nature & art1 betwe5 natural & artificial ?+s1 is v easily made & v conv5i5t1 x is ne$ful to rememb] t1 9 ! long run1 we owe ev]y?+ to nature2 t ev5 ^? artificial objects :i* we commonly say are made by m51 are only natural objects %ap$ & mov$ by m52 & t1 9 ! s5se ( creat+1 t is to say1 ( caus+ some?+ to exi/ :i* did n exi/ 9 "s o!r %ape be=e1 man c make no?+ :atev]4 ,moreov]1 we mu/ recollect t :at m5 d 9 ! way ( %ap+ & br++ toge!r or sep>at+ natural objects1 is done 9 virtue ( ! p[]s :i* !y !mselves possess z natural objects4 ,artificial ?+s are1 9 fact1 all produc$ by ! action ( t "p ( nature :i* we call mank9d1 ^u ! re/4 ,we talk ( 8mak+0 a box1 & rightly en\gh1 if we mean only t we h %ap$ ! pieces ( wood & nail$ !m toge!r2 b ! wood is a natural object & s is ! iron ( ! nails4 ,a wat* is 8made0 ( ! natural objects gold & o!r metals1 s&1 soda1 rubies1 br\ght toge!r1 & %ap$ 9 v>i\s ways2 a coat is 8made0 ( ! natural object1 wool2 & a frock ( ! natural objects1 cotton or silk4 ,moreov]1 ! m5 :o make all ^! ?+s are natural objects4 ,c>p5t]s1 build]s1 %oemak]s1 & all o!r artisans & arti/s1 are p]sons :o h le>n$ s mu* ( ! p[]s & prop]ties ( c]ta9 natural objects1 & ( ! *a9 ( causes & effects 9 nature1 z enables !m to %ape & put toge!r ^? natural objects1 s z to make !m useful to man4 ,a c>p5t] c\ld n1 z we say1 8make0 a *air unless he knew some?+ ( ! prop]ties & p[]s ( wood2 a blacksmi? c\ld n 8make0 a horse%oe unless he knew t x is a prop]ty ( iron to become s(t & easily hamm]$ into %ape :5 x is made r$-hot2 a brickmak] mu/ "k _m ( ! prop]ties ( clay2 & a plumb] c\ld n d 8 "w unless he knew t lead has ! prop]ties ( s(tness & flexibility1 & t a mod]ate heat causes x to melt4 ,s t ! practice ( e art implies a c]ta9 k ( natural causes & effects2 & ! improvem5t ( ! arts dep5ds ^u our le>n+ m & m ( ! prop]ties & p[]s ( natural objects1 & discov]+ h[ to turn ! prop]ties & ! p[]s ( ?+s & ! connections ( cause & effect among !m to our own advantage4 #g4 ,_m ,objects & ,*a9s ( ,causes & ,effects 9 ,nature are out ( our rea*4 ,among natural objects1 z we h se51 !re are "s t we c get hold ( & turn to acc\nt4 ,b all ! greate/ ?+s 9 nature & ! l9ks ( cause & effect :i* connect !m1 are utt]ly beyond our rea*4 ,! sun rises & sets2 ! moon & ! />s move ?r\gh ! sky2 f9e wea!r & /orms1 cold & heat1 alt]nate4 ,! sea *anges f viol5t di/urbance to glassy calm1 z ! w9ds sweep ov] x ) v>y+ /r5g? or die away2 innum]able plants & animals come 9 be+ & vani% aga91 )\t our be+ able to ex]t ! slighte/ influ5ce on ! maje/ic procession ( ! s]ies ( great natural ev5ts4 ,hurricanes ravage "o spot2 e>?quakes de/roy ano!r2 volcanic eruptions lay wa/e a ?ird4 ,a f9e season scatt]s weal? & abundance "h1 & a long dr\ght br+s pe/il5ce & fam9e !re4 ,9 all su* cases1 ! direct influ5ce ( man avails him no?+2 &1 s long z he is ignorant1 he is ! m]e sport ( ! great] p[]s ( nature4 #h4 ,! ,ord] ( ,nature3 no?+ happ5s by ,accid5t1 & !re is no su* ?+ z ,*ance4 ,b ! fir/ ?+ t m5 le>n$1 z soon z !y began to /udy nature c>efully1 0 t "s ev5ts take place 9 regul> ord] & t "s causes always give rise to ! same effects4 ,! sun always rises on "o side & sets on ! o!r side ( ! sky2 ! *anges ( ! moon foll[ "o ano!r 9 ! same ord] & ) simil> int]vals2 "s />s nev] s9k bel[ ! horizon ( ! place 9 :i* we live2 ! seasons are m or less regul>2 wat] always fl[s d[n-hill2 fire always burns2 plants gr[ up f se$ & yield se$1 f :i* l plants gr[ up aga92 animals are born1 gr[1 rea* maturity1 & die1 age aft] age1 9 ! same way4 ,?us ! notion ( an ord] ( nature & ( a fixity 9 ! relation ( cause & effect betwe5 ?+s gradually ent]$ ! m9ds ( m54 ,s f> z su* ord] prevail$ x 0 felt t ?+s 7 expla9$2 :ile ! ?+s t c\ld n be expla9$ 7 said to h come ab\t by *ance1 or to happ5 by accid5t4 ,b ! m c>efully nature has be5 /udi$1 ! m widely has ord] be5 f\nd to prevail1 :ile :at seem$ disord] has prov$ to be no?+ b complexity2 until1 at pres5t1 no "o is s fooli% z to believe t any?+ happ5s by *ance1 or t !re are any real accid5ts1 9 ! s5se ( ev5ts :i* h no cause4 ,& if we say t a ?+ happ5s by *ance1 ev]ybody admits t all we really mean is1 t we d n "k its cause or ! reason :y t p>ticul> ?+ happ5s4 ,*ance & accid5t are only aliases ( ignorance4 ,at ?is pres5t mom5t1 z ,i look out ( my w9d[1 x is ra9+ & bl[+ h>d1 & ! bran*es ( ! trees are wav+ wildly to & fro4 ,x may be t a man has tak5 %elt] "u "o ( ^! trees2 p]haps1 if a /rong] gu/ ?an usual comes1 a bran* w break1 fall ^u ! man1 & s]i\sly hurt him4 ,if t happ5s x w be call$ an 8accid5t10 & ! man w p]haps say t by 8*ance0 he w5t out1 & !n 8*anc$0 to take refuge "u ! tree1 & s ! 8accid5t0 happ5$4 ,b !re is nei!r *ance nor accid5t 9 ! matt]4 ,! /orm is ! effect ( causes op]at+ ^u ! atmosph]e1 p]haps hundr$s ( miles away2 e vibration ( a leaf is ! consequ5ce ( ! me*anical =ce ( ! w9d act+ on ! surface expos$ to x2 if ! b\gh breaks1 x w d s 9 consequ5ce ( ! relation betwe5 its /r5g? & ! =ce ( ! w9d2 if x falls ^u ! man x w d s 9 consequ5ce ( ! action ( o!r def9ite natural causes2 & ! position ( ! man "u x is only ! la/ t]m 9 a s]ies ( causes & effects1 :i* h foll[$ "o ano!r 9 natural ord]1 f t cause1 ! effect ( :i* 0 8 sett+ out1 to t ! effect ( :i* 0 8 /epp+ "u ! tree4 ,b1 inasmu* z we are n wise en\gh to be able to unravel all ^! long & complicat$ s]ies ( causes & effects :i* lead to ! fall+ ( ! bran* ^u ! man1 we call su* an ev5t an accid5t4 #i4 ,laws ( ,nature2 ,laws are n ,causes4 ,:5 we h made out by c>eful & repeat$ obs]vation t some?+ is always ! cause ( a c]ta9 effect1 or t c]ta9 ev5ts always take place 9 ! same ord]1 we speak ( ! tru? ?us discov]$ z a law ( ,nature4 ,?us x is a law ( nature t any?+ heavy falls to ! gr\nd if x is unsupport$2 x is a law ( nature t1 "u ord9>y conditions1 lead is s(t & heavy1 :ile fl9t is h>d & brittle2 because exp]i5ce %[s u t heavy ?+s always d fall if !y are unsupport$1 t1 "u ord9>y conditions1 lead is always s(t & t fl9t is always h>d4 ,9 fact1 ev]y?+ t we "k ab\t ! p[]s & prop]ties ( natural objects & ab\t ! ord] ( nature may prop]ly be t]m$ a law ( nature4 ,b x is desirable to rememb] t :i* is v (t5 =gott51 t ! laws ( nature are n ! causes ( ! ord] ( nature1 b only our way ( /at+ z mu* z we h made out ( t ord]4 ,/ones d n fall to ! gr\nd 9 consequ5ce ( ! law j /at$1 z p sometimes c>elessly say2 b ! law is a way ( ass]t+ t :i* inv>iably happ5s :5 heavy bodies at ! surface ( ! e>?1 /ones among ! re/1 are free to move4 ,! laws ( nature are1 9 fact1 9 ?is respect1 simil> to ! laws :i* m5 make = ! guidance ( _! conduct t[>ds "o ano!r4 ,!re are laws ab\t ! paym5t ( taxes1 & !re are laws aga9/ /eal+ or murd]4 ,b ! law is n ! cause ( a man's pay+ 8 taxes1 nor is x ! cause ( 8 ab/a9+ f !ft & murd]4 ,! law is simply a /atem5t ( :at w happ5 to a man if he does n pay 8 taxes1 & if he commits !ft or murd]2 & ! cause ( 8 pay+ 8 taxes1 or ab/a9+ f crime 79 ! abs5ce ( any bett] motive7 is ! fe> ( consequ5ces :i* is ! effect ( 8 belief 9 t /atem5t4 ,a law ( man tells :at we may expect society w d "u c]ta9 circum/ances2 & a law ( nature tells u :at we may expect natural objects w d "u c]ta9 circum/ances4 ,ea* conta9s in=mation address$ to our intellig5ce1 & except s f> z x influ5ces our intellig5ce1 x is m]ely s mu* s\nd or writ+4 ,:ile !re is ?is mu* analogy betwe5 human & natural laws1 h[ev]1 c]ta9 ess5tial diff]5ces betwe5 ! two mu/ n be ov]look$4 ,human law consi/s ( comm&s address$ to volunt>y ag5ts1 :i* !y may obey or disobey2 & ! law is n r5d]$ null & void by be+ brok54 ,natural laws1 on ! o!r h&1 are n comm&s b ass]tions respect+ ! inv>iable ord] ( nature2 & !y rema9 laws only s long z !y c be %[n to express t ord]4 ,to speak ( ! violation1 or ! susp5sion1 ( a law ( nature is an absurdity4 ,all t ! phrase c really mean is t1 "u c]ta9 circum/ances ! ass]tion conta9$ 9 ! law is n true2 & ! j conclusion is1 n t ! ord] ( nature is int]rupt$1 b t we h made a mi/ake 9 /at+ t ord]4 ,a true natural law is an univ]sal rule1 &1 z su*1 admits ( no exceptions4 ,aga91 human laws h no mean+ ap>t f ! exi/5ce ( human society4 ,natural laws express ! g5]al c\rse ( nature1 ( :i* human society =ms only an insignificant fraction4 #aj4 ,k ( ,nature is ! ,guide ( ,practical ,conduct4 ,if no?+ happ5s by *ance1 b ev]y?+ 9 nature foll[s a def9ite ord]1 & if ! laws ( nature embody t :i* we h be5 able to le>n ab\t ! ord] ( nature 9 accurate language1 !n x becomes v important = u to "k z _m z we c ( ^! laws ( nature1 9 ord] t we may guide our conduct by !m4 ,any man :o %\ld attempt to live 9 a c\ntry )\t ref]5ce to ! laws ( t c\ntry w\ld v soon f9d himself 9 tr\ble2 & if he 7 f9$1 imprison$1 or ev5 hang$1 s5sible p w\ld probably consid] t he _h e>n$ 8 fate by 8 folly4 ,9 l mann]1 any "o :o tries to live ^u ! face ( ?is e>? )\t att5tion to ! laws ( nature w live !re = b a v %ort "t1 mo/ ( :i* w be pass$ 9 exce$+ discom=t2 a peculi>ity ( natural laws1 z di/+ui%$ f ^? ( human enactm5t1 be+ t !y take effect )\t summons or prosecution4 ,9 fact1 nobody c\ld live = half a day unless he att5d$ to "s ( ! laws ( nature2 & ?\s&s ( u are dy+ daily1 or liv+ mis]ably1 because m5 h n yet be5 suffici5tly zeal\s to le>n ! code ( nature4 ,x has already be5 se5 t ! practice ( all our arts & indu/ries dep5ds ^u our kn[+ ! prop]ties ( natural objects :i* we c get hold ( & put toge!r2 & ?\gh we may be able to ex]t no direct control ov] ! great] natural objects & ! g5]al succession ( causes & effects 9 nature1 yet1 if we "k ! prop]ties & p[]s ( ^! objects1 & ! cu/om>y ord] ( ev5ts1 we may elude t :i* is injuri\s to u1 & pr(it by t :i* is fav\rable4 ,?us1 ?\gh m5 c n[ise alt] ! seasons or *ange ! process ( gr[? 9 plants1 yet hav+ le>n$ ! ord] ( nature 9 ^! matt]s1 !y make arrangem5ts = s[+ & reap+ accord+ly2 !y _c make ! w9d bl[1 b :5 x does bl[ !y take advantage ( its kn[n p[]s & probable direction to sail %ips & turn w9dmills2 !y _c arre/ ! lightn+1 b !y c make x h>mless by means ( conductors1 ! con/ruction ( :i* implies a k ( "s ( ! laws ( t electricity1 ( :i* lightn+ is "o ( ! manife/ations4 ,=ew>n$ is =e>m$1 says ! prov]b2 & k ( ! laws ( nature is =ew>n+ ( t :i* we may expect to happ51 :5 we h to deal ) natural objects4 #aa4 ,sci5ce3 ! ,k ( ! ,laws ( ,nature obta9$ by ,obs]vation1 ,exp]im5t1 & ,reason+4 ,no l9e c be drawn betwe5 common k ( ?+s & sci5tific k2 nor betwe5 common reason+ & sci5tific reason+4 ,9 /rictness all accurate k is ,sci5ce2 & all exact reason+ is sci5tific reason+4 ,! me?od ( obs]vation & exp]im5t by :i* su* great results are obta9$ 9 sci5ce1 is id5tically ! same z t :i* is employ$ by e "o1 e day ( 8 life1 b ref9$ & r5d]$ precise4 ,if a *ild acquires a new toy1 he obs]ves its "* & exp]im5ts ^u its prop]ties2 & we are all ( u con/antly mak+ obs]vations & exp]im5ts ^u "o ?+ or ano!r4 ,b ^? :o h nev] tri$ to obs]ve accurately w be surpris$ to f9d h[ difficult a bus9ess x is4 ,!re is n "o p]son 9 a hundr$ :o c describe ! commone/ occurr5ce ) ev5 an approa* to accuracy4 ,t is to say1 ei!r he w omit some?+ :i* did occur1 & :i* is ( importance2 or he w imply or sugge/ ! occurr5ce ( some?+ :i* he did n actually obs]ve1 b :i* he unconsci\sly inf]s mu/ h happ5$4 ,:5 two tru?ful witnesses contradict "o ano!r 9 a c\rt ( ju/ice1 x usually turns out t "o or o!r1 or sometimes bo?1 are conf\nd+ _! inf]5ces f :at !y saw ) t :i* !y actually saw4 ,a swe>s t ,b pick$ 8 pocket4 ,x turns out t all t ,a really kn[s is t he felt a h& 9 8 pocket :5 ,b 0 close to him2 & t ,b 0 n ! ?ief1 b ,c1 :om ,a did n obs]ve4 ,untra9$ obs]v]s mix up toge!r _! inf]5ces f :at !y see ) t :i* !y actually see 9 ! mo/ wond]ful way2 & ev5 exp]i5c$ & c>eful obs]v]s are 9 con/ant dang] ( fall+ into ! same error4 ,sci5tific obs]vation is su* z is at once full1 precise1 & free f unconsci\s inf]5ce4 ,exp]im5t is ! obs]vation ( t :i* happ5s :5 we int5tionally br+ natural objects toge!r1 or sep>ate !m1 or 9 any way *ange ! conditions "u :i* !y are plac$4 ,sci5tific exp]im5t1 !re=e1 is sci5tific obs]vation p]=m$ "u accurately kn[n artificial conditions4 ,x is a matt] ( common obs]vation t wat] sometimes freezes4 ,! obs]vation becomes sci5tific :5 we asc]ta9 "u :at exact conditions ! *ange ( wat] into ice takes place4 ,! commone/ exp]im5ts tell u t wood floats 9 wat]4 ,sci5tific exp]im5t %[s t1 9 float+1 x displaces its own weight ( ! wat]4 ,sci5tific reason+ diff]s f ord9>y reason+ 9 j ! same way z sci5tific obs]vation & exp]im5t diff] f ord9>y obs]vation & exp]im5t--t is to say1 x /rives to be accurate2 & x is j z h>d to reason accurately z x is to obs]ve accurately4 ,9 sci5tific reason+ g5]al rules are collect$ f ! obs]vation ( _m p>ticul> cases2 &1 :5 ^! g5]al rules are e/abli%$1 conclusions are d$uc$ f !m1 j z 9 e-day life4 ,if a boy says t 8m>bles are h>d10 he has drawn a conclusion z to m>bles 9 g5]al f ! m>bles he happ5s to h se5 & felt1 & has reason$ 9 t mode :i* is te*nically t]m$ induction4 ,if he decl9es to try to break a m>ble ) 8 tee?1 x is because he consci\sly1 or unconsci\sly1 p]=ms ! conv]se op]ation ( d$uction f ! g5]al rule 8m>bles are too h>d to break ) "o's tee?40 ,y w le>n m ab\t ! process ( reason+ :5 y /udy ,logic1 :i* treats ( t subject 9 full4 ,at pres5t1 x is suffici5t to "k t ! laws ( nature are ! g5]al rules respect+ ! behavi\r ( natural objects1 :i* h be5 collect$ f innum]able obs]vations & exp]im5ts2 or1 9 o!r words1 t !y are inductions f ^? obs]vations & exp]im5ts4 ,! practical & !oretical results ( sci5ce are ! products ( d$uctive reason+ f ^! g5]al rules4 ,?us sci5ce & common s5se are n oppos$1 z p sometimes fancy !m to be1 b sci5ce is p]fect$ common s5se4 ,sci5tific reason+ is simply v c>eful common reason+1 & common k gr[s into sci5tific k z x becomes m & m exact & complete4 ,! way to sci5ce !n lies ?r\gh common k2 we mu/ ext5d t k by c>eful obs]vation & exp]im5t1 & le>n h[ to /ate ! results ( our inve/igations accurately1 9 g5]al rules or laws ( nature2 f9ally1 we mu/ le>n h[ to reason accurately f ^! rules1 & ?us arrive at rational explanations ( natural ph5om5a1 :i* may suffice = our guidance 9 life4 ,,ii4 ,,mat]ial ,,objects4--,a4 ,,m9]al ,,bodies4 #ab4 ,! ,natural ,object ,wat]4 ,"o ( ! commone/ ( common natural objects is wat]2 ev]ybody uses x 9 "o way or ano!r e day2 & consequ5tly ev]ybody possesses a /ore ( loose in=mation--( common k--ab\t x4 ,b1 9 all probability1 a great deal ( ?is k has nev] be5 att5d$ to by its possessor2 & c]ta9ly1 ^? :o h nev] tri$ to le>n h[ mu* may be kn[n ab\t wat]1 w be ignorant ( a great _m ( its p[]s & prop]ties & ( ! laws ( nature :i* x illu/rates2 & consequ5tly w be unable to acc\nt = _m ?+s ( :i* ! explanation is v easy4 ,s we may z well make a beg9n+ ( sci5ce by /udy+ wat]4 #ac4 ,a ,tumbl] ( ,wat]4 ,suppose we h a tumbl] half-full ( wat]4 ,! tumbl] is an artificial object 7 #e72 t is to say1 c]ta9 natural objects h be5 br\ght toge!r & heat$ till !y melt$ into glass1 & ?is glass has be5 %ap$ by a workman4 ,! wat]1 on ! o!r h&1 is a natural object1 :i* has come f "s riv]1 pond1 or spr+2 or x may be f a wat]-butt into :i* ! ra9 :i* has fall5 on ! ro( ( a h\se has fl[$4 ,n[ ! wat] has a va/ numb] ( peculi>ities4 ,= example1 x is transp>5t1 s t y c see ?r\gh x2 x feels cool2 x w qu5* ?ir/ & dissolve sug>4 ,b ^! are n ! *>act]s :i* x is mo/ conv5i5t to beg9 )4 #ad4 ,wat] occupies ,space2 x (f]s ,resi/ance2 x has ,weight2 & is able to transf] ,motion :i* x has acquir$2 x is !re=e a =m ( ,matt]4 ,! wat]1 we see1 fills ! cavity ( ! tumbl] = half its height1 !re=e x occupies t mu* space1 or has t bulk or volume4 ,if y put ! clos$ end ( ano!r tumbl] ( almo/ ! same size into ! fir/1 y w f9d t :5 x rea*es ! wat]1 ! latt] (f]s a resi/ance to its go+ d[n1 & unless "s ( ! wat] c get out1 ! end ( ! second tumbl] w n g 94 ,any "o :o falls f a height into wat] w f9d t he receives a sev]e %ock :5 he rea*es x4 ,wat] !re=e (f]s resi/ance4 ,if ! wat] is empti$ out1 ! tumbl] feels mu* light] ?an x 0 be=e2 wat]1 !re=e1 has weight4 ,&1 f9ally1 if y ?r[ ! wat] out ( ! tumbl] at any slightly support$ object1 ! wat] hitt+ aga9/ x w\ld knock x ov]4 ,t is to say1 ! wat] be+ put 9 motion is able to transf] t motion to some?+ else4 ,all ^! ph5om5a1 z ?+s :i* happ5 9 nature are (t5 call$1 are effects ( :i* wat]1 "u ! conditions m5tion$1 is ! cause1 & !y may !re=e be said to be prop]ties 7 #d7 ( wat]4 ,all ?+s :i* occupy space1 (f] resi/ance1 possess weight & transf] motion to o!r ?+s :5 !y /rike aga9/ !m1 are t]m$ mat]ial sub/ances or bodies1 or simply matt]4 ,wat]1 !re=e1 is a k9d1 or =m1 ( matt]4 #ae4 ,wat] is a liquid4 ,y w easily obs]ve t1 ?\gh wat] occupies space1 x has no def9ite %ape1 b fits itself exactly to ! figure ( ! vessel :i* holds x4 ,if ! tumbl] is cyl9drical1 ! cont\r ( ! surface ( ! wat] w be circul> :5 ! tumbl] is held v]tically1 & w *ange1 )\t ! lea/ break or int]ruption1 to m & m ( an oval :5 ! tumbl] is incl9$1 & :atev] ! %ape ( ! vessel into :i* y p\r x1 ! sides ( ! wat] always exactly fit aga9/ ! sides ( ! vessel4 ,if y put y\r f+] into ! wat] y c move x 9 all directions ) sc>cely any feel+ ( ob/acle4 ,if y pull y\r f+] out !re is no hole left1 ! wat] on all sides ru%+ toge!r to fill up ! space t 0 occupi$ by ! f+]4 ,y _c take up a h&ful ( wat]1 = x runs away betwe5 y\r f+]s1 & y _c raise x into a p]man5t heap4 ,all ?is %[s t ! p>ts ( wat] move ^u "o ano!r ) great ease4 ,! same fact is illu/rat$ if ! tumbl] is incl9$ s t ! level ( ! surface rises above ! edge ( ! tumbl] on "o side1 & ! wat] is !re=e to "s ext5t unsupport$ by ! tumbl] at ?is po9t4 ,! wat] !n fl[s ov] 9 a /ream & falls to ! gr\nd1 :]e x spreads out & runs to ! l[e/ accessible place1 or gradually soaks up into crevices4 ,nev]!less1 al?\gh ! p>ts ( ! wat] ?us loosely slip & slide ^u "o ano!r1 yet !y hold toge!r to a c]ta9 ext5t4 ,if ! surface ( ! wat] is j t\*$ ) ! f+]1 a little ( x w adh]e2 & if ! f+] is !n sl[ly & c>efully rais$1 ! adjac5t wat] w be rais$ up into a sl5d] column :i* acquires a noticeable l5g? be=e x breaks4 ,s1 9 ! e>ly morn+1 aft] heavy dew1 y may see ! wat] ^u cabbage-leaves & blades ( grass 9 sph]ical drops1 ! p>ts ( :i* simil>ly hold toge!r4 ,mat]ial sub/ances1 ! p>ts ( :i* are s movable t !y fit !mselves exactly to ! sides ( any vessel :i* conta9s !m1 & :i* fl[ :5 !y are n support$1 are call$ fluids1 & fluids ! p>ts ( :i* d n fly (f f "o ano!r1 b hold toge!r z ^? ( wat] d1 are call$ liquids4 ,wat] !re=e is a liquid4 #af4 ,wat] is almo/ incompressible4 ,x has be5 se5 t wat]1 l e o!r mat]ial sub/ance1 resi/s ! intrusion ( o!r matt] into ! place :i* x occupies4 ,b _m ?+s1 ?\gh !y resi/1 c be easily squeez$ or compress$ into a small] volume4 ,?is1 h[ev]1 is n ! case ) wat]1 :i* l o!r liquids1 is almo/ incompressible2 t is to say1 an imm5se pressure is ne$ful to cause its volume to dim9i% to any appreciable ext5t4 ,x may seem /range t any?+ s app>5tly yield+ z wat] %\ld yet be almo/ z difficult to squeeze z s mu* iron2 b ! app>5t yield+ness ( wat] is due to ! ease ) :i* x *anges its %ape2 &1 if wat] is prev5t$ f *ang+ its %ape1 x is v difficult to drive its p>ts clos] toge!r4 ,x has be5 asc]ta9$ t if wat] is conf9$ 9 a clos$ space1 a pressure am\nt+ to fifte5 p\nds on ! squ>e in* dim9i%es its volume by only #a_/bjjjj? "p4 ,take a common syr+e1 & hav+ se5 t ! plug or pi/on fits ! cyl9d] ( ! syr+e well1 put ! nozzle into wat] & draw ! pi/on up4 ,!n turn ! nozzle upw>d & pu% ^u ! pi/on till a little ( ! wat] squirts out1 s z to make sure t ! cyl9d] conta9s no?+ b wat]4 ,n[ put y\r f+] on ! op5+ ( ! nozzle firmly1 s z to /op any wat] f pass+ out1 & !n try to pu% ! pi/on d[n4 ,y w f9d t y _c make x /ir )\t great =ce2 &1 if ! pi/on moves appreciably1 x w be because "s ( ! wat] has escap$ by ! sides ( ! pi/on4 ,9 fact1 if ! pi/on pres5t$ a squ>e in* ( surface1 & fitt$ accurately1 & ! column ( wat] 9 ! cyl9d] 7 "o in* long1 x mu/ be press$ d[n by a weight ( #cj1jjj p\nds 7ab\t ?irte5 tons7 to make x move "o-t5? ( an in*4 #ag4 ,! ,mean+ ( ,weight4 ,let u next consid] ! prop]ty ( weight4 ,we say t any?+ has weight :51 on try+ to lift x f ! gr\nd1 or on hold+ x 9 ! h&1 we h a feel+ ( ef=t4 ,or aga91 if any?+ :i* is support$ at a c]ta9 height above ! gr\nd1 falls :5 ! support is tak5 away1 we say t x has weight4 ,n[ ! gr\nd m]ely means ! surface ( ! e>?2 &1 z all bodies :i* possess weight fall directly t[>ds ! surface ( ! e>? :5 !y are n kept away f x by "s support1 we may say t all bodies :i* h weight t5d to fall 9 ?is way4 ,& x does n matt] on :at "p ( ! surface ( ! e>? y make ! exp]im5t4 ,ra9 consi/s ( drops ( wat]1 & x does n matt] :e!r we wat* a %[] 9 calm wea!r "h1 or 9 ,new ,zeal&2 ! drops fall p]p5dicul>ly t[>ds ! gr\nd4 ,b we "k t ! e>? is a globe1 & t ,new ,zeal& is at our antipodes1 or on ! opposite side ( ! globe to ,engl&4 ,h5ce if two %[]s are fall+ at ! same "t1 "o 9 ,new ,zeal& & "o "h--! drops mu/ be fall+ 9 opposite directions1 t[>ds "o ano!r2 t is1 t[>ds ! c5tre ( ! e>? :i* lies betwe5 !m4 ,9 fact1 all bodies :i* h weight t5d to fall t[>ds ! c5tre ( ! e>?--t is to say !y fall 9 ?is way if !re is no?+ to prev5t !m2 & :5 we speak ( weight we mean ?is t5d5cy to fall4 ,to call any?+ heavy1 is ! same z say+ t we fully expect t1 if !re is no?+ to support x1 x w fall to ! gr\nd2 or t if we support x ourselves we %all be consci\s ( ef=t4 #ah4 ,gravity & ,gravitation4 ,! ^w gravity1 :5 x 0 fir/ us$1 _h exactly ! same mean+ z weight2 & a body :i* has weight is said to gravitate t[>ds ! c5t] ( ! e>?4 ,b gravity has n[ acquir$ a mu* wid] s5se ?an weight4 ,= an imm5se numb] ( c>eful obs]vations & exp]im5ts h e/abli%$ ! g5]al rule1 or law ( nature1 t e mat]ial sub/ance1 t5ds to approa* e o!r mat]ial sub/ance1 j 9 ! same way z a drop ( ra9 falls t[>ds ! e>?2 &1 9 fact1 t any two portions ( matt]1 :atev] ! nature ( t matt] may be1 w move t[>ds "o ano!r if !re is no?+ to prev5t !m f do+ s4 ,to make ?is cle>1 let u suppose t ! only mat]ial bodies 9 ! univ]se 7 two sph]ical drops ( wat]1 ea* a t5? ( an in* 9 diamet]4 ,ea* ( ^! drops w\ld h ! same bulk z ! o!r1 & w\ld be a quantity ( matt] exactly equival5t to ! o!r4 ,!n1 h[ev] great ! di/ance :i* sep>at$ ^! two drops1 !y w\ld beg9 to approa* "o ano!r2 &1 ea* mov+ ) gradually increas+ swiftness1 !y w\ld at l5g? meet 9 a po9t exactly half-way betwe5 ! positions :i* !y at fir/ occupi$4 ,b if ! bulk ( "o drop 7 great] ?an t ( ! o!r drop1 !n ! l>g] w\ld move m sl[ly1 & ! po9t ( meet+ w\ld be by s mu* ne>] ! l>g] drop4 ,x foll[s t1 if ! "o body ( wat] 7 z big z ! e>? & ! o!r rema9$ ( its orig9al size1 no bigg] ?an a ra9-drop--! motion ( ! l>ge mass t[>ds ! small "o w\ld be an inconceivably m9ute fraction ( ! total di/ance travell$ ov]4 ,x w\ld appe> z if ! l>ge body 7 p]fectly /ill & drew ! small body to itself4 ,?is is j :at happ5s :5 a s+le drop ( wat] falls f a cl\d1 say ?r\gh a di/ance ( a mile1 to ! e>?4 ,! e>? really moves t[>ds x1 j z x moves t[>ds ! e>?1 on ! /raight l9e :i* jo9s ! c5tres ( ! two4 ,b ! l5g? ( ?is l9e :i* ea* travels ov] is inv]sely proportional to ! quantity ( matt] 9 ea*1 t is to say is ! less ! bigg] ! quantity4 ,s t we h a rule-(-?ree sum4 ,z ! quantity ( matt] 9 ! e>? is to t 9 a ra9-drop1 s is a mile to ! di/ance travell$ ov] by ! e>?4 ,& if any "o work$ out ?is sum1 he w\ld f9d t ! f\r? t]m ( ! proportion w\ld be an inconceivably m9ute fraction ( an in*4 ,= all practical purposes1 !re=e1 we may consid] ! e>? to be at re/ 9 relation to all fall+ bodies1 inasmu* z ! quantity ( matt] 9 any fall+ body is insignificant1 9 comp>ison ) t conta9$ 9 ! e>?4 ,:at is true ( wat] is true1 s f> z we "k1 ( all k9ds ( matt]1 & we !re=e say t x is a law ( nature t all k9ds ( matt] possess gravity2 t is to say1 t ( any two1 ea* t5ds to move t[>ds ! o!r1 at a spe$ :i* is ! sl[] ! great] ! quantity ( matt] x conta9s 9 proportion to t :i* ! o!r conta9s2 & ?is spe$ gradually becomes quick] z ! two bodies approa*4 ,:at is usually call$ ! law ( gravitation is a /atem5t ( ! same obs]v$ facts 9 ano!r & m complete fa%ion4 7,see ,physics ,prim]47 #ai4 ,! cause ( ,weight3 ,attraction3 ,=ce4 ,we "k no?+ :atev] ( ! reason :y bodies possess weight4 ,bodies d n fall on acc\nt ( ! law ( gravitation 7 #i72 nor does _! gravity expla9 :y !y fall4 ,gravity1 z we h se51 is only a "n = weight1 & ! law ( gravitation is only a /atem5t ( h[ bodies approa* "o ano!r1 n :y !y d s4 ,x is (t5 said t gravitation is attraction1 & t bodies fall to ! e>? because ! e>? attracts !m4 ,b ! ^w 8attract0 simply means to 8draw t[>ds10 & 8attraction0 means no?+ b 8draw+ t[>ds20 & to say1 :5 two bodies move t[>ds "o ano!r1 t !y are 8drawn t[>ds0 "o ano!r1 is simply to describe ! fact & makes u no :it wis] ?an we 7 be=e4 ,on ! contr>y1 unless we take great c>e1 x may make u a little less wise4 ,= ! words 8draw+ t[>ds0 are s closely associat$ ) ropes & hooks & ! act ( pull+1 t we are easily l$ to fancy ! exi/5ce ( "s analog\s invisible ma*9]y 9 ! case ( mutually attractive bodies4 ,aga91 gravitation is spok5 ( z a =ce2 & z ! ^w =ce is 9 v common use1 let u try to make out :at we mean by x4 ,a man is said to ex]t =ce :5 he pu%es or pulls any?+ s z ei!r to ex]t pressure ^u x or to put x 9 motion4 ,a wre/l]'s =ce is prov$ by 8 hug2 a b[l]'s =ce is %[n by ! swiftness ( motion ( ! ball4 ,=ce1 !n1 is ! "n :i* we give to t :i* causes or1 9 ! case ( pressure1 t5ds to cause1 motion4 ,! =ce ( gravity !re=e means ! cause ( ! pressure :i* we feel :5 bodies :i* possess gravity are support$ by our bodies1 & ! cause ( _! movem5t t[>ds ! c5tre ( ! e>?1 :5 !y are free to move4 ,b x is exactly ab\t ! cause ( ^! ph5om5a t we "k no?+ :atev]4 ,a good deal ( mis*ief is done by ! inaccurate use ( su* words z attraction & =ce1 z if !y 7 ! names ( ?+s hav+ an exi/5ce ap>t f natural objects1 & f ! s]ies ( causes & effects :i* are op5 to our obs]vation2 :ile !y are1 9 reality1 m]ely ! names ( ! unkn[n causes ( c]ta9 ph5om5a4 ,& x is wor? :ile to take pa9s to get cle> ideas on ?is head at ! outset ( ! /udy ( sci5ce4 ,let u rememb] !n t1 s f> z we "k1 x is a law ( nature1 t any two mat]ial bodies1 if !y are free to move1 approa* "o ano!r ) gradually increas+ swiftness2 & t ! space ov] :i* ea* travels be=e ! two meet1 is inv]sely proportional to ! quantity ( matt] :i* x conta9s4 ,attraction ( gravitation is a "n = ?is g5]al fact2 weight is ! "n = ! fact 9 ! case ( t]re/rial bodies2 =ce is a "n :i* we give to ! unkn[n cause ( ! fact4 ,! fact is t :i* x is important to "k4 ,! names are ( no great consequ5ce s long z we recollect t !y are m]ely names & n ?+s4 #bj4 ,! ,weight ( ,wat] is ,proportion$ to its ,bulk4 ,we mu/ next consid]1 n weight 9 g5]al1 b ! weight ( wat]4 ,we say t a tumbl] full ( wat] is heavi] ?an an empty tumbl]1 because ! full tumbl] gives u a great] feel+ ( ef=t :5 we lift x ?an ! empty tumbl] does4 ,! m wat] !re is 9 ! tumbl] ! great] is ! ef=t4 ,a pail full ( wat] requires /ill m ef=t1 ?\gh ! empty pail feels q light2 &1 :5 we come to deal ) a l>ge tub full ( wat]1 we may be unable to /ir x1 ?\gh ! empty tub c\ld be lift$ ) ease4 ,?us x seems t ! great] ! bulk ( wat] ! m x weighs1 & ! less ! bulk ! less x weighs4 ,b !n a s+le drop ( wat] 9 ! palm ( ! h& seems to weigh no?+ at all4 ,h[ev]1 ?is cle>ly _c be1 = ! drop falls to ! gr\nd readily1 & !re=e x mu/ h weight4 ,moreov]1 a few ?\s& drops w\ld fill ! tumbl]1 & if a ?\s& drops weigh some?+1 ea* drop mu/ h a ?\s&? ( t weight4 ,! fact is t our feel+ ( ef=t is a v r\gh measure ( weight1 & does n enable u to comp>e small weights1 or ev5 to p]ceive !m if !y are v small4 ,to "k any?+ accurately ab\t weight we mu/ h rec\rse to an in/rum5t :i* is contriv$ = ! purpose ( measur+ weights ) precision4 #ba4 ,! ,measur+ ( ,weights4 ,! ,balance4 ,su* an in/rum5t is ! balance or scales1 :i* y may see 9 e groc]'s %op4 ,x is compos$ ( a beam :i* moves easily on a pivot fix$ to its middle1 & :i* has a scale-pan atta*$ to ea* end4 ,s long z bo? scale-pans are empty ! beam is horizontal2 b if y put any?+ :i* has weight into "o1 t "o goes d[n & ! o!r rises4 ,if n[ y ei!r pull or pu% ! empty scale d[nw>ds1 ! beam may be br\ght into ! horizontal position aga91 & ! ef=t requir$ to br+ x into ! horizontal position w be ! great]1 ! great] ! weight ( ! body 9 ! opposite scale4 ,an ounce 9 ! "o scale is easily rais$ by ! pressure ( a f+] 9 ! o!r4 ,a p\nd requires m ef=t2 t5 p\nds ne$s putt+ out ! /r5g? ( ! arm2 to raise fifty p\nds involves /ill m ex]tion2 :ile a c\ple ( hundr$weight w n be /irr$ by ! /ronge/ pu% or pull ^u ! empty scale4 ,suppose t1 in/ead ( press+ d[n ! empty scale1 y put some?+ t has weight into x2 !n1 z soon z ?is weight is equal to t 9 ! o!r scale1 ! beam w become horizontal4 ,9 fact1 "o scale has j z mu* t5d5cy to move t[>ds ! c5tre ( ! e>? z ! o!r has1 & z nei!r c g d[n )\t pull+ ! o!r up1 !y neutralise "o ano!r4 ,x comes to ! same ?+1 z if two boys ( equal /r5g? 7 pull+ "o aga9/ ! o!r2 s long z ! pulls 9 opposite directions are equal1 ( c\rse nei!r boy c /ir2 :ile ! smalle/ addition ( /r5g? to "o enables him to pull ! o!r ov]4 #bb4 ,! ,weight ( ! same ,bulk or ,volume ( ,wat] is ,con/ant "u ! same conditions4 ,mass4 ,d5sity4 ,n[ let two graduat$ ?9 glass measures be put into ! two scales1 & made to c\nt]poise "o ano!r exactly4 ,!n1 if ev5 a s+le drop ( wat] is put into ! "o measure ! scale w desc5d1 if ! balance is a good "o2 %[+ t ! drop has weight4 ,if ! measures are graduat$ accurately1 !n :atev] volume ( wat] is put into "o1 an exactly simil> volume ( ! same wat] mu/ be put into ! o!r to make ! beam level4 ,?is obvi\sly means t ! same volume ( wat] "u ! same circum/ances always has ! same weight4 ,9 #ah x 0 said t bodies t5d to move t[>ds "o ano!r ) a relative velocity#a :i* is inv]sely proportional to ! quantity ( matt] :i* !y conta94 ,b h[ are we to measure quantity ( matt]8 ,is x to be e/imat$ by ! space :i* x occupies2 t is1 by its volume8 or are we to e/imate ! quantity ( matt] 9 a body by its weight8 ,y w soon le>n t ! volume ( all bodies is con/antly *ang+ 9 correspond5ce ) ! *anges 9 ! pressure ex]t$ by o!r bodies1 b m especially 9 correspond5ce ) ! *anges ( temp]ature to :i* !y are subject$2 :ile ! weight ( ! same body1 at ! same po9t on ! e>?'s surface1 nev] alt]s4 ,h5ce we may take ! weight ( a body z a measure ( ! quantity ( matt] :i* x conta9s2 & x foll[s t1 = ! same weight1 ! l>g] ! volume ( a body ! less matt] x conta9s proportionally to its volume1 & ! less ! volume1 ! m matt] x conta9s4 ,! proportion ( its weight to its volume gives u ! d5sity ( a body4 ,footnote #a3 ,velocity1 or swiftness1 is measur$ by ! di/ance ov] :i* a body travels1 9 a giv5 "t4 ,( two bodies1 "o ( :i* travels ?r\gh "o foot 9 a second1 :ile ! o!r travels ?r\gh two feet1 ! latt] has ! great] relative velocity4 ,n[ :at is true ( wat] is true ( all o!r bodies or mat]ial sub/ances4 ,suppose t "o ( ! measures is empti$ & replac$1 ! beam may be br\ght to ! horizontal position aga9 by means ( a piece ( lead cut to exactly ! "r size4 ,! piece ( lead w !nce=? furni% an exactly correspond+ or equival5t weight = s mu* wat]2 & pieces ( iron or brass1 :i* c\nt]poise ! lead1 w also be equival5ts ( ! weight ( ! wat]1 or ( ! lead1 or ( "o ano!r4 ,b ! pieces ( lead1 iron1 or brass w obvi\sly be ( mu* less volume or bulk ?an ! wat] :i* !y c\nt]poise4 ,"h x foll[s t ! d5sities ( ^! metals1 or ! quantity ( matt] conta9$ 9 ! same volume1 mu/ be mu* great] ?an 9 ! case ( wat]4 ,:at are call$ weights 9 comm]ce are pieces ( lead1 or iron1 or brass exactly equival5t 9 weight to a c]ta9 bulk ( wat] "u c]ta9 conditions4 ,an imp]ial gallon ( wat] ?us weighs t5 p\nds1 & !re=e an imp]ial p9t weighs a p\nd & a qu>t]4 #bc4 ,equal ,volumes ( ,diff]5t ,?+s "u ! same circum/ances1 h ,diff]5t ,weights3 ! ,d5sity ( ,diff]5t ,bodies is ,diff]5t4 ,! important fact :i* has j be5 allud$ to mu/ be consid]$ m fully4 ,we h se5 t an imp]ial p9t measure gives u ! space :i* is tak5 up by z mu* wat] z weighs a p\nd & a qu>t]2 & ?is space is ! bulk or volume ( t weight ( wat]4 ,b if y take an ord9>y p\nd weight & a qu>t]-p\nd weight1 & put !m into an imp]ial p9t measure1 y w f9d t in/ead ( fill+ x1 !y take up only a v small portion ( ! space 9 its int]ior1 or 9 o!r words1 ( its capacity4 ,?us ! volume ( a p\nd & a qu>t] ( lead1 or ( iron1 or ( brass1 is v mu* less ?an ! volume ( ! same weight ( wat]2 t is to say1 ! metals are d5s] ?an wat]2 ! same volume has great] mass or m gravity4 ,or1 to put ! case 9 ano!r way1 fill ! tumbl] ) :i* we began half full ( wat]1 mak+ a m>k on ! side exactly at ! level ( ! top ( ! wat]4 ,!n place x 9 "o scale ( a balance1 & c\nt]poise x ) weights 9 ! o!r4 ,next1 p\r out ! wat]1 & aft] dry+ ! tumbl]1 fill x ) f9e s& c>efully up to ! m>k4 ,! volume ( s& w be equal to ! volume ( wat]4 ,b n[ ! same weights w no long] c\nt]poise x1 & y w h to put m weights 9 ! opposite scale4 ,volume = volume1 !re=e1 s& is heavi] ?an wat]4 ,?r[ out ! s&1 & put 9 sawdu/ 9 ! same way1 & y w f9d t a less weight ?an 0 necess>y to c\nt]poise ! wat] c\nt]poises ! sawdu/4 ,volume = volume1 !re=e1 sawdu/ is light] ?an wat]4 ,exp]im5t 9 ! same way ) _s & oil1 & !y w be f\nd to be light] ?an wat]1 :ile treacle w be heavi]1 & quicksilv] v mu* heavi] ?an wat]4 #bd4 ,! ,mean+ ( ,heavy & ,light--,specific ,gravity4 ,we are 9 ! habit ( us+ ! words heavy & light r c>elessly4 ,we call ?+s t are easily lift$ light1 & ?+s t are h>d to lift heavy4 ,we say t s&1 :i* is bl[n ab\t by ! w9d1 is light1 & t a block ( wood is heavy1 & yet we h j se5 t s& is heavi]1 bulk = bulk1 ?an wood4 ,9 ord] to get rid ( ?is d\ble mean+1 ! weight ( a volume ( any liquid or solid1 9 proportion to ! weight ( ! same volume ( wat] at a kn[n temp]ature & pressure1 is call$ its specific gravity4 ,wat] be+ tak5 z #a1 any?+ a volume ( :i* is twice z heavy z ! same volume ( wat] is said to h ! specific gravity #b2 if ?ree times1 #c2 if f\r & a half times1 #de1 & s on4 ,?us ! specific gravity ( any liquid or solid expresses its d5sity 9 proportion to t ( wat] "u ! same conditions4 ,sawdu/1 oil1 & _s h a less specific gravity ?an wat]1 :ile treacle1 s&1 & quicksilv] h a great] specific gravity4 ,9 ?is s5se1 ! =m] ?ree sub/ances are light1 :ile ! latt] ?ree are heavy4 #be4 ,?+s ( great] ,specific ,gravity ?an ,wat] s9k 9 ,wat]2 ,?+s ( less ,specific ,gravity float4 ,"h are two tumbl]s ( wat]4 ,?r[ "s s& into "o & "s sawdu/ into ! o!r4 ,:at happ5s8 ,! s& s9ks to ! bottom1 ! sawdu/ floats at ! top4 ,we may /ir !m up z we l1 b ! s& w tumble to ! bottom & ! sawdu/1 z ob/9ately1 rise to ! top4 ,?us t :i* is light] ?an ! wat] floats1 & t :i* is heavi] 7bulk = bulk7 s9ks4 ,s1 if we p\r "s oil into ! wat]1 x floats1 & if we p\r "s col\r$ _s 9 c>efully1 x also floats2 :ile treacle & quicksilv] s9k to ! bottom1 j z ! iron-fil+s d4 ,we saw t ! iron-fil+s sank1 because iron is heavi] ?an wat]4 ,"h is a piece ( ! ?9 t9n$ %eet-iron t !y make t9 boxes (4 ,:at w happ5 if we drop x into ! wat]8 ,x is heavi] ?an wat]1 bulk = bulk1 & !re=e x w s9k z y see x does4 ,b n[ "h is a 8t90 cani/] made ( ?is v same t9n$ %eet-iron4 ,we drop t into ! wat]1 & y see x does n s9k at all1 b floats at ! top z if x 7 made ( cork4 ,"h is a p]plexity4 ,we 7 sure j n[ t iron is heavi] ?an wat]1 & "h is an iron box float+6 ,is ?is an exception to ! law8 ,n at all2 = :at we said 0 t a ?+ w\ld float if x 7 light]1 bulk = bulk1 ?an wat]4 ,n[ let u weigh ! t9 box1 & hav+ weigh$ x let u next try to f9d out h[ mu* ! same bulk ( wat] weighs4 ,?is may be done v simply1 = ! walls ( ! box are v ?91 s t ! inside ( ! box is v ne>ly z l>ge z ! :ole box4 ,consequ5tly1 if we fill ! box ) wat]1 & !n weigh ! wat]1 we %all f9d out1 v ne>ly1 :at is ! weight ( a bulk ( wat] z great z t ( ! box4 ,b if we d ?is1 we %all f9d t ! wat] :i* 0 conta9$ 9 ! box1 weighs v mu* m ?an ! box does4 ,s t1 bulk = bulk1 ! box1 al?\gh x is made ( iron1 is really light] ?an wat]1 & t is :y x floats4 ,y w all h he>d ( ! iron %ips :i* are n[ s common1 & y may h wond]$ h[ x is1 t %ips made ( ?ick plates ( iron rivet$ toge!r1 & weigh+ _m ?\s& tons1 d n g to ! bottom4 ,b !y are no?+ b our t9 cani/]s on a great scale1 & !y float because ea* %ip weighs less ?an a quantity ( wat] ( ! same bulk does4 ,x is because ( ?is prop]ty ( wat] to be> up ?+s light] ?an itself1 & because ( t o!r prop]ty ( be+ easily mov$ :i* ! p>ticles ( wat] h1 t ! sea1 & riv]s1 & canals1 are su* great highways = mank9d4 ,= !re is no?+ s heavy t x may n be made to float 9 wat]1 if ! box :i* holds x is l>ge en\gh to make ! weight ( ! :ole less ?an ! weight ( ! same bulk ( wat]4 ,& !n1 hav+ once got ! weight to float1 ! p>ticles ( wat] are s easily mov$1 t ! =ce ( ! w9ds1 or ( o>s1 or ( paddles1 readily causes x to slip ?r\gh ! wat] f "o place to ano!r4 #bf4 ,a ,body :i* ,floats 9 ,wat] always occupies z mu* ,space b5ea? ! level ( ! ,surface ( ! ,wat] z is equal to ! ,volume ( ,wat] :i* weighs z mu* z t ,body2 9 o!r words1 x displaces its own ,weight ( ,wat]4 ,a cubic in* ( wat] weighs ab\t #beb gra9s & a half4 ,suppose t ! t9 box 9 ! previ\s exp]im5t 0 squ>e1 & _h ! bulk ( #ajj cubic in*es1 !n ! weight ( a correspond+ volume ( wat] w\ld be #be1bej gra9s4 ,if ! box weigh$ #h1daf gra9s1 j a ?ird ( its bulk w\ld be imm]s$2 if #ab1fbe gra9s1 half2 if #af1hcb gra9s1 x w\ld s9k two-?irds ( its volume1 & s on4 ,or1 if1 :5 ! box is float+1 y make a m>k ^u its side at ! exact level ( ! surface ( ! wat]1 ! bulk ( t portion ( ! box :i* lies bel[ ! wat]-level c be asc]ta9$4 ,suppose x to be ?irty cubic in*es1 !n ! weight ( ! box w be #cj #bebe or #gege gra9s4 ,h5ce x may be said t ! imm]s$ "p ( a float+ body takes ! place ( ! wat] :i* x displaces1 &1 z x 71 repres5ts x4 ,if y press d[nw>ds ^u ! float+ box1 !re is a feel+ ( resi/ance z x desc5ds1 & :5 ! pressure is tak5 (f1 ! body imm$iately rises aga94 ,h5ce ! wat] presses upw>ds aga9/ ! bottom ( ! float+ body4 ,b x also presses aga9/ ! sides1 = if ! sides ( ! box are v ?9 !y w be driv5 94 ,if a ?9 empty bottle is tightly cork$ & l[]$ into deep wat] ! cork w be driv5 91 or else ! bottle w be cru%$4 #bg4 ,wat] presses 9 all ,directions4 ,?us wat] presses 9 all directions ^u ?+s :i* are imm]s$ 9 x4 ,if a long wood5 or metal pipe1 plac$ v]tically1 has its l[] end /opp$ ) a cork :i* does n fit v tightly1 & wat] is p\r$ into ! top ( ! tube1 ! wat] w at fir/ fill ! "p ( ! tube above ! cork1 & its weight w ex]t a c]ta9 pressure on ! cork4 ,9 fact1 if ! end ( ! tube is /opp$ by apply+ ! palm ( ! h& closely aga9/ x1 ! d[nw>d pressure ( ! wat] w h to be ov]come by a c]ta9 am\nt ( ef=t4 ,z ! wat] accumulates1 ?is d[nw>d pressure w become great] & great] until ! h& is driv5 away1 or ! cork is =c$ out1 & ! wat] falls to ! gr\nd4 ,! pressure 9 ?is case is ! same z ! weight ( ! wat]1 & ! cork w\ld h be5 driv5 out equally well by a rod ( lead ( ! same weight4 ,suppose ! tube to be squ>e1 & t ! inside ( ! squ>e measures exactly "o in* ea* way4 ,!n an in* ( height ( ! tube w hold exactly "o cubic in* ( wat]4 ,s9ce "o cubic in* ( wat] weighs #beb gra9s & a half1 z mu* wat] z w fill ! tube ab\t two feet ?ree in*es & a half high1 w weigh a p\nd 7#g1jjj gra9s71 & fifte5 p\nds ( wat] w fill su* a tube betwe5 ?irty-?ree & ?irty-f\r feet high4 ,& ^! respective weights measure ! pressure ( two columns ( wat]1 "o tw5ty-sev5 & a half in*es high1 & ! o!r ne>ly ?irty-f\r feet high1 on a squ>e in* ( ! surface on :i* !y re/4 ,! specific gravity 7 #bd7 ( lead is #aade2 9 o!r words x is ab\t elev5 & a half times d5s] ?an wat]4 ,!re=e if a b> ( lead cut squ>e & "o in* 9 ! side1 & r less ?an #a_/aa? ( ! height ( a column ( wat]1 is slipp$ into ! tube 9 place ( ! wat]1 x w ex]t ! same pressure on ! bottom4 ,& n[ comes a diff]5ce betwe5 ! lead & ! wat]1 :i* dep5ds on ! fluidity ( ! latt]4 ,! lead ex]ts no pressure on ! sides ( ! tube1 b ! wat] does4 ,if a small hole is cut 9 ! side ( ! tube close to ! bottom1 & /opp$ ) a cork1 ! lead w n press ^u ! cork4 ,b if ! column ( wat] is high en\gh ! cork w be driv5 out ) z mu* =ce z be=e1 s t ! wat] presses j z mu* sideways z d[nw>ds4 ,x is easy to satisfy oneself ( ?is by ins]t+ a long glass tube1 ) its l[] end b5t at "r angles & fitt$ ) a cork1 into ! side ( ! wood5 pipe4 ,! wat] w at once rise 9 ! tube to ! same height z x has 9 ! pipe4 ,:5ce x is obvi\s t ! pressure ( ! wat] on any po9t ( ! side is exactly equal to ! v]tical pressure at t po9t2 = ! pressure outw>ds is exactly balanc$ by t ( ! v]tical column 9 ! tube inw>ds4 ,! wat] 9 a wat]+-pot always /&s at ! same level 9 ! c & 9 ! sp\t4 ,if a glass tube is b5t into ! %ape ( a ,u1 & wat] is p\r$ into x1 ! wat] w always /& at ! same level 9 ! two legs ( ! tube1 :atev] ! %ape ( ! b5d may be1 or ! relative capacities ( ! two legs1 or ! incl9ation ( ! tube4 ,& ?is mu/ ne$s be s1 = ! =ce ) :i* ! wat] t5ds to fl[ out ( ! "o half ( ! arrangem5t dep5ds on ! v]tical height#b ( ! surface ( ! wat] above ! ap]ture ( exit2 s t any column ( equal v]tical height mu/ balance x4 ,footnote #b3 ,v]tical height is ! height measur$ along a l9e drawn f ! surface ( ! wat] p]p5dicul>ly to ! surface ( ! e>?4 ,a plumb-l9e is a /r+ to "o end ( :i* a weight is atta*$ & ?us hangs susp5d$4 ,if ! o!r end ( ! l9e is br\ght opposite ! surface ( ! wat] ! direction ( ! /r+ answ]s to ! l9e ( v]tical height4 ,t a column ( wat] w /& at exactly ! same level z any o!r ) :i* x communicates1 may be se5 /ill m simply by plac+ a glass tube1 op5 at ea* end1 9 a bas9 ( wat]4 ,h[ev] ! tube may be incl9$ or b5t1 :e!r its l[] end is wide or n>r[1 ! column ( wat] inside x w be at exactly ! same level z ! wat] outside x4 ,yet1 ( c\rse1 ! rigid glass walls ( ! tube cut (f all communication betwe5 ! column ( wat] inside x & ! re/1 except at ! bottom4 ,9 a well-ord]$ t[n1 wat] is suppli$ to e h\se & c be drawn f taps plac$ 9 ! highe/ /ories4 ,^! are f$ by pipes :i* lead f a ci/]n at ! top ( ! h\se4 ,?is wat] is br\ght f a l>ge pipe1 or ma91 9 ! /reet1 by a small] h\se-pipe1 :i* is (t5 made to twi/ ab\t 9 v>i\s directions be=e x rea*es ! ci/]n at ! top ( ! h\se into :i* x deliv]s ! wat]4 ,if y foll[$ ! ma91 y w\ld f9d t x took a long c\rse up & d[n1 b5ea? ! pavem5t ( ! /reets1 until at la/ x rea*$ ! wat]-works4 ,"h y w\ld f9d t ! ma9 0 connect$ ) a res]voir2 & ei!r ?is res]voir is at a great] height ?an any ( ! ci/]ns into :i* ! wat] is deliv]$1 or !re is "s means ( pump+ ! wat] f x to t height on its way to ! ma94 ,?us ! res]voir1 ! ma91 & ! h\se-pipe =m "o imm5se ,u-tube1 & ! wat] 9 ! h\se-pipe t5ds to rise to ! same level z t ( ! wat] 9 ! res]voir1 & h5ce fl[s into ! ci/]n :5 ! supply-pipe is op54 #bh4 ,! ,transf]5ce ( ,motion by ,mov+ ,wat]3 ! ,mom5tum ( ,mov+ ,wat]4 ,suppose a wood5 vat ) a horizontal tap1 ! sectional area#c ( ! tube ( :i* is "o squ>e in*1 ins]t$ close to ! bottom1 to be fill$ ) wat] up to #ajj in*es above ! tap4 ,!n suppos+ ! tap to be %ut1 ! pressure ^u its sectional area w be #be1bej gra9s1 or r m ?an ?ree p\nds & a half--& !re is ! same pressure on e squ>e in* ( ! bottom ( ! vat4 ,footnote #c3 ,! sectional area ( a tube is ! surface occupi$ by its cavity :5 x is cut across4 ,x w\ld be repres5t$ by ! surface ( a piece ( c>dbo>d1 l ! wad ( a gun1 j l>ge en\gh to g into ! tube4 ,if ! tap is n[ turn$1 ! wat] ne>e/ to x be+ unsupport$ on its out] side1 ! pressure on ! inn] side sets x 9 motion1 & x fl[s out 9 a /ream4 ,at fir/ ! /ream %oots out viol5tly & ! wat] is c>ri$ to a long di/ance4 ,t is to say1 ! weight ( ! column ( wat] #ajj in*es high acts z a =ce1 or cause ( motion1 ^u ! wat] ne>e/ ! tap1 & ?is wat] is =c$ out ) a velocity dep5d+ on t =ce 9 a horizontal direction4 ,n[ suppose t y take a common toy cup-&-ball & br+ ! ball into ! way ( ! /ream ( wat]4 ,! /ream w at once /rike ! ball & drive x 9 ! same direction z t :i* x is itself tak+4 ,! p[] :i* ! mov+ wat] has ( transf]r+ or communicat+ motion to a body :i* is at re/1 b free to move z ! ball is1 is due to its mom5tum4 ,! great] ! mass ( ! /ream & ! m rapidly x moves1 ! m motion w x communicate to ! ball1 or ! heavi] ! ball x w move4 ,close to ! m\? ( ! tap ! direction ( ! /ream is horizontal2 b x v soon beg9s to b5d d[nw>ds1 & describ+ a rapid curve1 comes to ! gr\nd4 ,x does ?is = j ! same reasons t a /one ?r[n horizontally describes a curve2 & at l5g? /rikes ! gr\nd2 &1 9 fact1 ! /ream may be reg>d$ z s mu* wat] ?r[n horizontally4 ,^! reasons are two3 fir/ly1 z soon z ! wat] has left ! tap x is an unsupport$ heavy body2 &1 z su*1 x beg9s to fall to ! gr\nd4 ,secondly1 ! mom5tum ( ! wat] is cont9ually be+ dim9i%$ by ! resi/ance ( ! air ?r\gh :i* x passes4 ,=1 al?\gh ! air :i* surr\nds u is s ?9 & movable a body t we ord9>ily take no notice ( x--! fact t x (f]s resi/ance to bodies :i* move ?r\gh x is easily obs]v$2 z1 = example1 9 us+ a fan4 ,! wat] has to ov]come ?is resi/ance1 & its mom5tum is proportionally dim9i%$4 ,if1 :5 ! wat] leaves ! tap1 ! air & gravitation 7 alike aboli%$1 ! wat]1 keep+ its mom5tum1 w\ld travel = ev] 9 ! same direction4 ,z ! wat] runs out1 x w be obs]v$ t ! velocity ( ! /ream becomes less & ! curve :i* x describes %>p]1 s t x comes to ! gr\nd soon]2 & f9ally1 :5 ! vat is ne>ly empty1 ! /ream falls ne>ly v]tically d[nw>ds4 ,! reason ( ?is is t ! level ( ! top ( ! wat] is gradually l[]$2 consequ5tly1 ! height ( ! column :i* presses on ! wat] close to ! tap is gradually less5$1 & !re=e its weight is dim9i%$4 ,b ?is weight or pressure is ! cause ( ! motion ( ! wat]1 & z ! cause dim9i%es ! effect ( t cause mu/ dim9i%4 ,!re=e ! mom5tum ( ! wat] is gradually less5$ & x is c>ri$ less & less f> horizontally 9 ! "t :i* x takes to fall to ! gr\nd3 until f9ally1 x acquires no appreciable horizontal motion at all1 & s falls v]tically d[nw>ds f ! m\? ( ! tap4 #bi4 ,! ,en]gy ( ,mov+ ,wat]4 ,if a %ort pipe b5t at "r angles l ! lett] ,l is fitt$ by "o arm on to ! end ( ! tap1 :ile ! o!r is turn$ v]tically upw>ds1 & ! vat is full z be=e2 :5 ! tap is turn$1 ! wat] w %oot up into ! air1 & aft] ris+ = a c]ta9 di/ance w /op1 & !n fall4 ,9 fact we %all h a f\nta94 ,obs]ve ! diff]5ce betwe5 ! v]tical jet ( wat] & ! horizontal jet4 ,if we leave ! resi/ance ( ! air out ( consid]ation1 ! wat] 9 ! horizontal jet has no ob/acle to ov]come2 & x might g on = ev]1 if its weight did n gradually cause its pa? to become m & m b5t t[>ds ! e>?1 aga9/ :i* x ev5tually /rikes4 ,:5 ! jet is v]tical ! case is alt]$4 ,! wat] ?r[n up v]tically con/antly t5ds to fall d[n v]tically1 z any o!r heavy body w\ld d1 & its mom5tum has to ov]come ! ob/acle ( its gravity4 ,any giv5 portion ( ! wat] is1 9 fact1 act$ ^u by two opposite t5d5cies1 mom5tum urg+ x up1 & gravity pull+ x d[n4 ,n[ if two equal t5d5cies exactly oppose "o ano!r1 ! body ^u :i* !y act does n move at all2 :ile1 if "o is /rong] ?an ! o!r1 ! body moves 9 ! direction ( ! /rong]4 ,?us a portion ( wat] :i* has j left ! sp\t %oots up1 because ! velocity ) :i* x is impell$ upw>ds is suffici5t to c>ry x ?r\gh a great] space 9 a giv5 "t1 say a second1 ?an t ?r\gh :i* its gravity w\ld1 9 ! same "t1 impel x d[nw>ds4 ,b ! di/ance :i* ! wat] w travel dur+ ?is second w be ! diff]5ce betwe5 ! di/ance :i* x w\ld h asc5d$ if !re _h be5 no gravity =c+ x d[n1 & ! di/ance :i* x w\ld h desc5d$ if !re _h be5 no mom5tum driv+ x up2 &1 at ! end ( ! second1 ! rate ( its motion upw>ds1 or its velocity1 w be proportionally sl[]4 ,?us1 at ! end ( ! fir/ second1 ! wat] has sp5t a c]ta9 portion ( its mom5tum 9 ov]com+ its gravity4 ,& z !re is no?+ to make good ! loss1 x w\ld1 if left to itself1 travel m sl[ly1 or ov] a less di/ance1 9 ! second second ?an x t5d$ to d 9 ! fir/4 ,b ?\gh ! mom5tum ( ! wat] is dim9i%$1 its gravity1 weight1 or t5d5cy to fall d[nw>ds1 = a giv5 di/ance 9 a second1 rema9s exactly :at x 01 & op]ates 9 ! c\rse ( ! second second to exactly ! same ext5t z 9 ! fir/4 ,h5ce1 at ! end ( ! second second1 ! di/ance ?r\gh :i* ! wat] travels upw>ds is /ill small]1 & its velocity is /ill m dim9i%$4 ,x is obvi\s t1 h[ev] great ! disproportion betwe5 mom5tum & gravity to />t )1 gravity mu/ ga9 ! day 9 ! long run "u ^! circum/ances4 ,! /ore ( mom5tum w be us$ up2 &1 aft] a mom5t>y re/1 ! wat]1 r$uc$ to ! condition ( a body )\t support1 w beg9 to be c>ri$ d[nw>ds by ! unoppos$ action ( gravity4 ,! case is simil> to t ( a boy scull+ a boat1 ! b[s ( :i* are sudd5ly seiz$ & ! boat ?ru/ viol5tly backw>ds by a /rong man4 ,! boat w g /]n-=emo/ rapidly1 at fir/1 b e /roke ( ! boy's o> at ! /]n w ret>d its backw>d motion2 until1 at l5g?1 ! /ock ( mom5tum conf]r$ ^u x by ! man's ?ru/ w be completely exhau/$ 9 work+ aga9/ ! boy1 & ! boat1 aft] a mom5t>y re/1 w resume its onw>d c\rse4 ,! di/ance to :i* ! boat w be propell$ backw>ds w evid5tly dep5d ^u ! am\nt ( muscul> p[] :i* ! man1 z x 71 sudd5ly capitalizes 9 ! boat1 & :i* ! boat !n sl[ly pays out4 ,we call p :o possess mu* muscul> or o!r p[] en]getic2 & we e/imate _! en]gy by ! ob/acles !y ov]come1 or1 9 o!r words1 by ! "w !y d4 ,9 ! pres5t illu/ration ! man's en]gy w\ld be measur$ by ! di/ance to :i* ! boat 0 propell$ be=e x /opp$4 ,x is easy to transf] ?is conception ( en]gy1 z ! p[] ( do+ "w1 to inanimate ?+s2 & ?us :5 a body 9 motion ov]comes any k9d ( ob/acles 9 its way1 p>t+ ) its mom5tum & m or less com+ to re/ 9 ! process1 we say t x has en]gy & t x does "w4 ,! en]gy ( mov+ wat] is ?us measur$ by ! int5sity ( ! oppos+ =ces :i* x c ov]come multipli$ into ! di/ance :i* x c travel be=e t en]gy is exhau/$2 t is to say1 by ! "w x does be=e x is itself r$uc$ to a /ate ( re/4 ,9 ! case "u consid]ation1 ! en]gy by :i* gravity is ov]come1 = a great] or less "t1 dep5ds ^u ! velocity ( ! /ream2 & ?is aga9 dep5ds ^u ! height ( ! wat] 9 ! vat above ! tap4 ,j z ! en]gy ( ! horizontal /ream dim9i%$ z ! level ( ! wat] became l[]1 s does ! en]gy ( ! v]tical /ream dim9i%4 ,h5ce1 z ! vat empties1 ! jet becomes %ort] & %ort]1 until at la/ x s9ks d[n to no?+4 ,! en]gy ( mov+ wat] makes x1 "u "s circum/ances1 "o ( ! mo/ de/ructive ( natural ag5ts2 &1 "u o!rs1 "o ( ! mo/ useful s]vants ( man4 ,a /ream is wat] fall+ d[n hill ) a velocity dep5d+ ^u ! incl9ation ( its b$4 ,z x falls x acquires mom5tum &1 h5ce1 en]gy2 & ?us a m\nta9 /ream1 sudd5ly swoll5 by ra9 or melt+ sn[1 w te> away masses ( rock & sweep ev]y?+ be=e x4 ,no?+ c look s(t] or m h>mless ?an a calm sea1 b if ! w9d sweep+ ov] its surface puts ! wat] 9 motion1 x /rikes ^u ! %ore ) t]rific =ce2 & its en]gy is exp5d$ 9 ?r[+ up great waves1 :i* lift va/ blocks or drive masses ( %+le up ! bea*4 ,9 all k9ds ( wat]mills x is ! en]gy ( m or less rapidly fall+ wat] :i* is turn$ to acc\nt4 ,! wat] is made to fl[ aga9/ buckets or floats atta*$ to ! circumf]5ce ( a :eel4 ,ea* bucket or float is !re=e an ob/acle to :i* ! wat] transf]s "s ( its own motion2 x moves away & ?us makes ! :eel to :i* x is fa/5$ turn4 ,b ! turn+ ( ! :eel br+s a new ob/acle 9 ! way ( ! /ream4 ,?is is treat$ 9 ! same fa%ion1 & ! :eel turns /ill fur!r1 ?us introduc+ ano!r ob/acle 9 ! way ( ! /ream ^u :i* ! same effect is produc$4 ,?us ea* float1 or bucket1 is a means by :i* "s ( ! mom5tum ( ! /ream is1 z x 71 caught & transf]r$ to ! wat]-:eel1 :i* consequ5tly turns r\nd ) a c]ta9 velocity4 ,b ?is wat]-:eel is n[ a mass ( matt] 9 motion1 & !re=e itself conta9s a /ore ( en]gy or p[] do+ "w4 ,if a cord ) a weight at ! end ( x 7 fa/5$ to ! axle ( ! :eel1 ! cord w\ld be w\nd ^u ! axle1 & ! weight c\ld be rais$1 or1 9 o!r words1 s mu* "w w\ld be done by ! turn+ ( ! :eel & we %\ld ?us h a r\gh measure ( ! am\nt ( en]gy :i* _h be5 giv5 up by ! /ream to ! :eel4 ,! ma*9]y ( ! mill is simply a set ( contrivances = transf]r+ ! en]gy /or$ up 9 ! wat]-:eel to ! place 9 :i* "w has to be done4 ,9 a fl\r-mill1 = example1 a s]ies ( :eels c>ries x f ! wat]-:eel to ! gr9d/ones1 :i* x sets 9 motion4 #cj4 ,! ,prop]ties ( ,wat] are ,con/ant4 ,if1 :5ev] !re is a %[]1 y cat* "s ra9-wat]1 y w f9d t x possesses all ! prop]ties :i* h be5 describ$4 ,x w be f\nd to be an almo/ incompressible liquid1 an imp]ial p9t ( :i* weighs ab\t a p\nd & a qu>t]4 ,x w\ld make no diff]5ce if ! ra9-wat] 7 collect$ 9 ,africa or 9 ,new ,zeal&2 or if x _h be5 obta9$ c5turies ago & kept bottl$ up ev] s9ce4 ,& !re is e reason to believe t ra9-wat] w h exactly ! same prop]ties a hundr$ or a ?\s& ye>s h5ce4 ,s f> z ! prop]ties ( ra9-wat] are conc]n$ ! ord] ( nature is con/ant4 ,?is1 h[ev]1 is by no means ! same ?+ z say+ t ! prop]ties ( wat] are always ! same4 ,9 fact ! prop]ties ( ! sub/ance1 wat]1 v>y imm5sely accord+ to ! conditions to :i* x is expos$2 b1 "u ! same conditions1 !y are ! same1 s t we may /ill say t s f> z wat] is conc]n$1 ! ord] ( nature is con/ant4 #ca4 ,increase ( ,heat at fir/ causes ,wat] to ,increase 9 ,volume4 ,x has be5 se5 t a c]ta9 weight ( wat] always has ! same volume "u ! same conditions4 ,! mo/ important ( ^! conditions is ! heat or cold to :i* x is expos$4 ,wat] :i* has /ood = "s "t 9 a w>m room becomes less 9 volume1 or contracts1 if x is tak5 into a cool place2 :ile its volume increases1 or x exp&s1 if x is made hot4 ,! same ?+ is true ( quicksilv]1 ( _s1 & ( liquids 9 g5]al4 ,a !rmomet] is simply a small flask--! bulb--) a long & n>r[ neck--! tube--fill$ ) z mu* m]cury or _s z w rise a %ort di/ance into ! neck4 ,if ! liquid 9 ! bulb is w>m$1 its volume is increas$ & x ov]fl[s into ! tube1 increas+ ! height ( ! column ( liquid 9 ! tube4 ,if1 on ! o!r h&1 ! liquid 9 ! bulb is cool$1 its volume is dim9i%$2 &1 z x %r9ks1 ! column ( liquid 9 ! tube fl[s back into ! bulb1 & ! level ( ! top ( ! column is l[]$4 ,if a m>k is made on ! tube1 or on a scale fix$ to x1 at ! po9t :i* ! liquid rea*es :5 ! bulb is plac$ 9 boil+ wat]2 & ano!r m>k at ! po9t to :i* x s9ks :5 ! bulb is 9 melt+ ice2 & ! space betwe5 ! two m>ks is divid$ into #ahj equal p>ts1 ea* ( ^! p>ts is :at is call$ a 8degree0 9 ! !rmomet]s ord9>ily us$ 9 ?is c\ntry 7call$ ,fahr5heit74 ,& if ! boil+-po9t is c\nt$ z #bab ! freez+-po9t mu/ be #cb 7#bab - #cb #ahj74 ,) ! same am\nt ( heat ! fluid 9 ! tube always /&s at ! same degree1 & h5ce ! in/rum5t measures temp]ature4 ,t hot wat] is light] ?an cold is easily se5 :5 a ba? is fill$ f two taps1 "o ( hot & "o ( cold wat]1 :i* run at ! same "t4 ,unless c>e is tak5 to /ir ! wat]1 ! top ( ! ba? w be v mu* hott] ?an ! bottom4 ,?us1 an imp]ial p9t ( wat] weighs a p\nd & a qu>t] only at a c]ta9 temp]ature or degree ( w>m?1 namely at #fb2 if x is made hott] its volume increases1 & !re=e its specific gravity dim9i%es4 ,x 0 = ?is reason t 9 #bb ! weight ( ! same volume ( wat] 0 said to be con/ant "u ! same conditions2 &1 ( c\rse1 ! same qualification mu/ be borne 9 m9d :5 we speak ( ! weight ( a cubic in* ( wat] be+ ab\t #beb & a half gra9s4 ,its weight is 9 fact #bebde gra9s only :5 ,fahr5heit's !rmomet] /&s at #fb--;b z ?is is ! temp]ature ( ord9>y mild wea!r1 & ! expansion or contraction ( wat] = a degree ab\t ?is temp]ature am\nts to less ?an #a_/cjjj? ( its volume1 ! weight ( a cubic in* may = all practical purposes be tak5 z #beb & a half gra9s4 #cb4 ,increase ( ,heat at l5g? causes ,wat] to become ,/eam4 ,?us a *ange is effect$ 9 ! prop]ties ( wat] by heat+ x ev] s little4 ,if x is m /rongly heat$ a /ill great] *ange takes place4 ,y "k :at happ5s :5 a saucepan conta9+ wat] is put on ! fire4 ,! wat] gets hott] & hott]1 !n x beg9s to simm]1 & f9ally1 :5 x rea*es #bab1 x boils away into /eam1 :i* passes into ! air & disappe>s4 ,if ! boil+ is c>ri$ on long en\gh all ! wat] vani%es4 ,x looks at fir/ z if ! wat] _h be5 de/roy$ by ! heat4 ,9 reality1 h[ev]1 n a p>ticle ( wat] has be5 de/roy$4 ,x has m]ely *ang$ its /ate4 ,! heat has alt]$ x f ! /ate ( liquid wat] into t ( gase\s wat]1 vap\r or /eam4 ,try ! same exp]im5t ) a tea-kettle in/ead ( a saucepan1 b only put a little wat] 9 ! tea-kettle1 & %ut ! lid well d[n4 ,!n1 z soon z ! wat] beg9s to boil1 ! /eam w %oot out ( ! sp\t 9 a jet2 & ?is w g on z long z any wat] rema9s 9 ! kettle4 ,! /eam1 z x comes out ( ! sp\t1 is s hot t x w scald y if y put y\r f+] 9 x4 ,b y may satisfy y\rself t x is v hot1 )\t scald+ y\r f+]s1 by hold+ a /ick ( seal+-wax 9 x4 ,! wax w s(t51 j z if y held x be=e ! fire4 ,moreov]1 if y look ?r\gh ! /eam1 j :]e x leaves ! sp\t1 y w see t x is q transp>5t2 x is only at "s little di/ance f ! sp\t t x loses its transp>5cy1 *anges into a :ite opaque cl\d1 & rapidly vani%es 9 ! air4 #cc4 ,! tak+ away ( ,heat f ,/eam causes ! /eam to *ange into ,hot ,wat]4 ,n[ take a cold spoon1 or a cold plate1 & hold x aga9/ ! jet ( /eam1 = a mom5t or two4 ,:5 y take x away1 y w f9d t x is q wet1 be+ cov]$ ) drops ( w>m wat]1 &1 moreov]1 ! cold spoon1 or plate1 has become w>m4 ,& if y fit a long cold metal pipe to ! nozzle ( ! tea-kettle1 y w f9d t no /eam at all issues f ! end ( ! pipe1 b only wat]1 :ile ! pipe becomes w>m$4 ,?us ! heat passes f ! fire into ! saucepan1 or kettle1 & !nce to ! wat] :i* !y conta92 ! wat] gets hott] & hott]1 &1 :5 x has tak5 9 a c]ta9 quantity ( heat1 x becomes /eam1 or vap\r ( wat]4 ,:5 ! /eam comes aga9/ ! cold plate1 or passes ?r\gh ! cold pipe1 x gives up ! heat x has tak5 9 to ! plate1 or ! metal ( ! pipe4 ,!y c>ry (f ! heat :i* kept ! wat] 9 a condition ( a vap\r1 & s x passes back into ! condition ( liquid4 ,?us /eam & wat] are two conditions ( ! same ?+1 wat]2 !y are effects ( ! quantity ( heat :i* ! wat] has tak5 94 #cd4 ,:5 ,wat] is *ang$ into ,/eam1 its ,volume becomes ab\t #a1gjj times great] t x 0 at fir/4 ,if y c\ld measure & weigh ! wat] 9 y\r kettle to beg9 )1 & !n measure & weigh all ! /eam into :i* ! heat ( ! fire *anges x1 y w\ld f9d t ! bulk ( ! /eam 0 ne>ly #a1gjj times z great z ! bulk ( ! wat]1 ?\gh ! weight ( ! /eam w\ld be exactly ! same z t ( ! wat]4 ,if y _h a small squ>e cup l a die1 ! inside measure ( :i* 0 exactly "o in* ea* way1 x w\ld hold "o cubic in* ( wat]4 ,if ?is cup full ( wat] 7 heat$ till all ! wat] 0 turn$ into /eam1 ! /eam w\ld ne>ly occupy a cubic foot2 s9ce !re are #a1gbh cubic in*es 9 a cubic foot4 ,a cubic in* ( wat] weighs #beb gra9s1 & ! /eam into :i* x is conv]t$ has j ! same weight4 ,?us we may say t /eam is wat] exp&$ by heat into a vap\r :i* is ( #a1gjj times less specific gravity ?an wat]4 ,on ! o!r h&1 a p9t ( /eam all[$ to cool1 becomes conv]t$ into a quantity ( wat]1 :i* measures only #a_/agjj? ( a p9t1 ?\gh x weighs j z mu* z ! :ole p9t ( /eam did4 ,! /eam1 !re=e1 is cond5s$ to a #a_/agjj? ( its volume ( wat]4 ,! p[] ) :i* wat] exp&s :5 x is conv]t$ into /eam is v great4 ,if y 7 to /op up ! nozzle ( ! tea-kettle1 ! /eam1 inside ! kettle1 9 try+ to exp&1 w\ld bur/ op5 ! lid2 & if y 7 to fa/5 d[n ! lid1 x w\ld pretty soon bur/ ! kettle itself4 ,y sometimes he> ( ! /rong boil]s ( /eam-eng9es be+ bur/ 9 ?is way4 #ce4 ,gases or ,ela/ic ,fluids4 ,air4 ,"h is a glass flask ) a long neck & an op5 m\?4 ,if we p\r wat] 9 at ! m\? until x rises to ! lip we say t ! flask is full ( wat]4 ,if we n[ p\r ! wat] out we say t ! flask is empty4 ,b is x empty8 ,press ! flask m\? d[nw>ds into a glass j> full ( wat]4 ,if ! flask 7 empty !re w\ld be no reason :y ! wat] %\ld n ent] ! neck ( ! flask & /& at ! same height inside ! neck z x does outside4 ,if y take an 8empty0 glass tube op5 at ea* end & press x d[n into ! wat]1 ! wat] inside & ! wat] outside w /& at ! same level4 ,b if y put y\r f+] on ! upp] end ( ! tube s z to conv]t x into a clos$ vessel1 ! wat] w ent] ! l[] end only a little way4 ,s ) ! flask1 ! wat] ent]s ! neck only a little way4 ,h5ce !re is some?+ inside ! 8empty0 tube & 9 ! 8empty0 flask2 some?+ :i* is mat]ial1 because x occupies space & (f]s resi/ance4 ,9 fact ! flask is full ( t =m ( matt] :i* is t]m$ air1 a ?ick coat ( :i* surr\nds ! e>? z ! atmosph]e4 ,air has weight1 z y w le>n m fully by & by2 & t air 9 motion c transf] t motion to o!r bodies y are taught by ! effects ( ! w9ds1 :i* are m]ely air 9 motion4 ,air !re=e has all ! *>act]s ( a mat]ial sub/ance4 ,moreov] x is a fluid1 = x fits itself exactly to ! %ape ( any vessel :i* conta9s x2 its p>ts are v easily mov$1 or we %\ld feel its resi/ance e "t we move a limb2 t x 8fl[s0 is se5 9 e breeze & e "t y use a pair ( bell[s1 :5 ! air is driv5 9 a /ream out ( ! nozzle2 & x presses on all sides any?+ conta9$ 9 x4 ,b ?\gh air is a fluid x is n a liquid4 ,9 ! fir/ place x is v compressible4 ,we saw t ! wat] ent]$ a little way into ! tube or ! neck ( ! flask 9 ! prec$+ exp]im5t4 ,! reason ( ?is is t ! wat] compresses ! air into a small] volume4 ,a bag full ( air1 su* z a common air-cu%ion1 c be squeez$ till ! air 9 its int]ior occupies a mu* small] volume2 &1 if y treat a syr+e full ( air 9 ! same way z ! syr+e full ( wat] 0 treat$1 y w f9d1 if ! pi/on fits well1 t x c be driv5 d[n "s di/ance & !n spr+s back aga94 ,air 9 fact is n only a compressible1 b x is an ela/ic fluid or gas4 ,heat exp&s air j z x exp&s wat]1 b ! expansion ( air = ! same degree ( heat is mu* great]4 #cf4 ,/eam is an ,ela/ic ,fluid or ,gas4 ,9 all ! prop]ties :i* h be5 m5tion$ wat] 9 ! =m ( /eam is an ela/ic fluid or gas l air4 ,if a little wat] is plac$ 9 ! flask m5tion$ 9 ! prec$+ section all ! 8empty0 "p ( ! space w conta9 air4 ,if ! flask is n[ made hot ! wat] w at l5g? boil1 bubbles ( /eam =m+ 9 ! wat] & break+ at its surface4 ,by degrees1 ! air1 :i* at fir/ lay above ! wat]1 w be driv5 out2 & if ! :ole flask is kept hot1 ! 8empty0 "p ( x w be full ( ! gase\s wat]1 :i* is transp>5t & col\rless l air4 ,! /eam fl[s out ( ! m\? ( ! flask /ill a cle> & col\rless gas2 b x soon cools & becomes cond5s$ z a cl\d ( small p>ticles ( fluid wat]4 ,/eam is light] ?an air1 & h5ce x rises 9 ! air1 j z bodies :i* are light] ?an wat] rise 9 wat]4 #cg4 ,gases & ,vap\rs4 ,air is z mu* a gas 9 ! colde/ w9t] z x is 9 ! hotte/ summ]4 ,b air c be liquefi$ by expos+ x to a v l[ temp]ature1 :ile1 at ! same "t1 x is subject$ to an extremely great pressure4 ,?us1 ! diff]5ce betwe5 gases l air1 :i* are cond5s$ ) extreme difficulty1 & gases l /eam1 :i* are cond5s$ easily1 is only "o ( degree4 ,nev]!less !re is a c]ta9 conv5i5ce 9 di/+ui%+ ^? gases1 :i*1 l /eam1 are easily cond5s$ z vap\rs4 ,9 :at we ord9>ily call /eam1 all ! wat] ( :i* x is compos$ rema9s gase\s only at & above ! temp]ature ( boil+ wat] 7#bab ,fahr5heit74 ,cool$ ev] s little bel[ ?is po9t1 mo/ ( x becomes cond5s$ into hot liquid wat]4 ,h[ev]1 x mu/ be recollect$ t ?\gh t p>ticul> =m ( gase\s wat] :i* we call /eam exi/s only at & above ! temp]ature ( boil+ wat]1 yet wat] is capable ( exi/+ 9 ! gase\s /ate d[n to ! freez+-po9t4 ,suppose t :5 our boil+ flask conta9$ no?+ b wat] & /eam1 ! m\? 7 /opp$ & ! lamp remov$4 ,!n1 s long z ! temp]ature ( ! :ole rema9$ at t ( boil+ wat]1 e cubic in* ( /eam above ! wat] 9 ! flask w\ld weigh ab\t ? ( a gra91 s9ce #ajj cubic in*es weigh ab\t #ae gra9s4 ,suppose ! capacity ( ! flask1 exclusively ( ! fluid wat] 9 x1 to be #ajj cubic in*es4 ,!n1 to beg9 )1 ! gase\s wat] :i* x conta9s w weigh #ae gra9s4 ,if ! flask is n[ all[$ to cool1 m & m ( ! gase\s wat] cond5ses into ! fluid /ate2 b1 ev5 d[n to ! freez+-po9t1 "s wat] w rema9 9 ! gase\s /ate & w fill t "p ( ! flask :i* is unoccupi$ by ! fluid wat]4 ,at blood-heat 7#ih7 ! gase\s wat] weighs only ab\t a gra91 ?\gh x /ill occupies #ajj cubic in*es2 at ! ord9>y temp]ature ( ! air x weighs n m ?an rd ( a gra92 :ile1 at ! freez+-po9t1 its weight is only ? ( a gra94 ,b inasmu* z !re is less & less actual weight ( wat] 9 ! same volume ( gase\s wat] z ! temp]ature falls1 x foll[s t ! d5sity1 or specific gravity1 ( ! gase\s wat] mu/ be less ! l[] ! temp]ature4 ,moreov]1 :ile1 at ! boil+-po9t1 gase\s wat] or /eam resi/s compression ) exactly ! same =ce z air does1 ! l[] ! temp]ature ! m easily compressible is ! gase\s wat]4 ,suppose an ela/ic bag 7 to be ti$ on to ! nozzle ( a kettle full ( boil+ wat]4 ,if ! bag 7 kept z hot z ! boil+ wat] x w\ld become fully di/5d$1 & ma9ta9 its %ape 9 spite ( ! pressure ( ! air ^u all sides ( x4 ,if ! bag 7 tak5 away x w\ld reta9 its %ape s long z x 0 kept z hot z boil+ wat]2 b1 if x 7 all[$ to cool1 x w\ld gradually become flatt5$ by ! outside air squeez+ up ! less & less resi/+ gase\s wat] ( ! l[] temp]atures4 ,h5ce1 :5 ! /opp$ flask has be5 all[$ to cool1 ! air ru%es 9 ) great viol5ce if x is op5$4 #ch4 ,! ,evaporation ( ,wat] at ord9>y ,temp]atures4 ,if "s wat] is p\r$ into a sauc] & is all[$ to /& ev5 9 a cool room or 9 ! op5 air1 y "k t x soon] or lat] disappe>s4 ,wet clo!s hung on a l9e soon dry--t is to say1 ! wat] cl++ to !m disappe>s or evaporates4 ,! disappe>ance ( ! wat] "u ^! circum/ances results f ! prop]ty j m5tion$4 ,9 fact1 x becomes gase\s wat] ( ! d5sity appropriate to ! temp]ature1 & z su* mixes ) ! air z any o!r gas w\ld d4 ,& z ! sea1 lakes1 & riv]s1 are con/antly giv+ (f gase\s wat] into ! air 9 proportion to ! temp]ature1 x is n wond]ful t ! atmosph]e always conta9s gase\s wat]4 ,air is said to be moi/ :5 ! weight ( wat] 9 a giv5 quantity1 say #ajj cubic in*es1 is z mu*1 or ne>ly z mu*1 z c exi/ 9 ! /ate ( gas at ! temp]ature4 ,"u ^! circum/ances1 if ! temp]ature is l[]$ ev5 a v little1 "s ( ! gase\s wat] is conv]t$ into liquid wat]4 ,we see ?is 9 hot moi/ wea!r1 :5 ! outside ( a tumbl] ( fre% drawn cold spr+ wat] imm$iately becomes b$ew$4 ,! gase\s wat] 9 imm$iate contact ) ! tumbl]1 9 fact1 is cool$ d[n bel[ ! po9t at :i* x c all exi/ z gas1 & ! sup]fluity is deposit$ z dew4 ,9 su* days wet clo!s d n dry well1 because !re is1 already1 ne>ly z mu* gase\s wat] 9 ! atmosph]e z ! am\nt ( heat m>k$ by ! !rmomet] c ma9ta9 9 t /ate4 #ci4 ,:5 ,hot ,wat] is cool$1 x ,contracts to beg9 )1 b aft] a "t ,exp&s4 ,we h n[ se5 :at a wond]ful *ange is br\ght ab\t by heat+ wat]4 ,at fir/1 x exp&s gradually & slightly2 b1 :5 x rea*es ! boil+-po9t1 x sudd5ly exp&s enorm\sly1 & is no long] a liquid1 b a gas4 ,on ! o!r h&1 if w>m wat] is all[$ to cool1 x gradually contracts till x rea*es ! ord9>y temp]ature ( ! air 9 mild wea!r2 b1 if ! wea!r is v cold1 or if ! wat] is cool$ artificially1 x goes on contract+ only d[n to a c]ta9 temp]ature 7#ci71 & !n beg9s to exp& aga94 ,9 ?is peculi>ity wat] is unlike all o!r bodies :i* are fluid at ord9>y temp]atures4 ,h5ce ! temp]ature ( #ci is t at :i* pure wat] has its greate/ d5sity or specific gravity1 & wat] at ?is temp]ature is heavi]1 bulk = bulk1 ?an ! same wat] at any o!r temp]ature4 ,!re=e if wat] at ! top ( a vessel is cool$ d[n to ?is temp]ature1 x falls to ! bottom1 & if ! wat] at ! bottom ( a vessel is cool$ bel[ ?is temp]ature x rises to ! top4 #dj4 ,wat] cool$ /ill fur!r becomes ! transp>5t brittle solid ,ice4 ,our tumbl] ( wat]1 if put out ( doors on a cold w9t]'s night1 w\ld gradually cool until x assum$ a temp]ature ( #ci ?r\gh\t4 ,cool+ bel[ ?is temp]ature1 ! wat] s cool$ w\ld gradually accumulate at ! surface by reason ( its less d5sity1 & its temp]ature w\ld fall till ! !rmomet] plac$ 9 x m>k$ #cb4 ,z soon z ?is upp] wat] cool$ ev] s little bel[ #cb1 a film l glass w\ld =m on its surface by ! conv]sion ( ! colde/ fluid wat] into solid wat] or ice4 ,& if all ! wat] cool$ d[n to ! same degree x w\ld all gradually *ange into ! same k9d ( sub/ance4 ,9 ?is condition wat] is solid4 ,x occupies space1 (f]s resi/ance1 has weight & transmits motion z ! wat] did1 b if y %ake x out ( ! tumbl] 9 a cold place x reta9s its =m )\t ! lea/ *ange4 ,if y press x1 x proves to be exce$+ly h>d & unyield+2 &1 if ! pressure is increas$1 x becomes cru%$ & breaks l glass4 ,x may ?us be cru%$ to p[d]1 & ! ice p[d] c be =m$ into heaps z if x 7 s&4 ,j z any quantity ( /eam has exactly ! same weight z ! wat] :i* 0 conv]t$ into x by heat2 s ! ice has exactly ! same weight z ! wat] :i* has be5 conv]t$ into x by tak+ away heat4 #da4 ,ice has less ,specific ,gravity ?an ! ,wat] f :i* x 0 =m$4 ,b ?\gh ! ice 9 ! tumbl] has ! same weight z ! wat] _h1 x has n ! same volume4 ,! expansion :i* began at #ci goes on1 & :5 wat] passes into ! solid /ate its volume is ab\t #a_/aa? great] ?an x 0 at #ci4 ,tak+ wat] at ?is temp]ature z #aj1 ice has a specific gravity ( #jiaf4 ,b al?\gh wat] 9 freez+ exp&s only to ?is small am\nt1 x resembles /eam 9 ! trem5d\s =ce ) :i* x exp&s4 ,if y fill a holl[ iron %ell q full ( wat]1 screw d[n ! op5+ tight1 & !n put x 9 a cold place :]e ! wat] may freeze1 ! wat] z x freezes w bur/ ! iron walls ( ! %ell4 ,y "k t :5 ! w9t] is sev]e1 ! pipes by :i* wat] is br\ght to a h\se (t5 bur/4 ,?is is because ! wat] 9 !m freezes1 &1 be+ unable to get out ( ! pipe1 bur/s x1 j z y may bur/ a jacket t is too tight = y by /ret*+ y\rself4 ,among ! b>e hill-tops1 or on ! face ( cliffs expos$ to ! wea!r1 ! /ronge/ & h>de/ rocks are e w9t] split & brok51 j z if qu>rym5 _h be5 at "w at !m4 ,9 ! summ] ! ra9-wat] gets into ! little cracks & rifts 9 ! /one & lodges !re4 ,!n ! w9t] comes ) its cold & freezes ! wat]4 ,& ! wat] bur/s ! rocks asund] j z x bur/s our wat]pipes4 #db4 ,ho> ,fro/ is ! ,gase\s ,wat] :i* exi/s 9 ! ,atmosph]e1 cond5s$ & conv]t$ into ,ice ,cry/als4 ,9 ! w9t]-"t y (t5 notice1 on a cle> %>p night1 t ! tops ( ! h\ses & ! trees are cov]$ ) a :ite p[d] call$ ho> fro/2 &1 on ! w9d[s ( ! room :5 y wake up1 y see mo/ beautiful figures1 l delicate plants4 ,take a little ( ! ho>-fro/1 or scrape (f "s ( ! /uff t makes ! w9d[ look l gr\nd glass1 & y f9d t x melts 9 y\r h& & turns to wat]4 ,x is 9 fact ice4 ,& if y look at ! figures on ! w9d[ pane ) a magnify+ glass y w see t !y are made up bits ( ice :i* h a def9ite %ape1 & are arrang$ 9 a regul> patt]n4 ,ea* ( ^! def9itely %ap$ bits ( ice has be5 =m$ 9 ! foll[+ way4 ,! air 9 ! room is mu* w>m] ?an t outside1 & !re is mix$ ) x ne>ly z mu* wat]1 d]iv$ f ! brea? & ! evaporation ( moi/ surfaces1 z c ma9ta9 itself 9 ! gase\s /ate at ! temp]ature4 ,! w9d[panes1 be+ ?91 are cool$ by ! outside air1 & ( c\rse ! gase\s wat] inside ! room1 :5 x comes 9 contact ) ! cold w9d[panes1 becomes cond5s$ on !m into f9e drops ( cold wat]4 ,! panes becom+ cold] & cold]1 ^! m9ute drops at la/ freeze1 & ! wat] n only becomes solid1 b x cry/allises2 t is to say1 ! little solid masses take on m or less regul> geometrical =ms ) flat faces1 incl9$ to "o ano!r at con/ant angles1 s t !y resemble bits ( glass cut accord+ to p>ticul> fix$ patt]ns4 ,all ice is 9 fact cry/all9e1 b 9 ice :i* has be5 =m$ f ?ick %eets ( wat]1 ! cry/als are s pack$ toge!r t !y _c be di/+ui%$ sep>ately4 #dc4 ,:5 ,ice is w>m$ x beg9s to *ange back into ,wat] z soon z ! ,temp]ature rea*es #cb4 ,a lump ( ice br\ght out ( ! op5 air 9 v cold wea!r may h a temp]ature ( #cj1 or #bj1 or l[]4 ,if su* a lump is br\ght into a w>m room x gradually becomes w>m]1 b rema9s un*ang$ o!rwise1 until x has ris5 to #cb4 ,!n x beg9s to melt1 & rema9s at #cb z long z x is melt+2 & ! wat] :i* proce$s f x is at fir/ also at #cb4 ,if y 7 to ?r[ a lump ( ice into ! middle ( a hot fire1 s long z a p>ticle ( ice rema9$ z su*1 x w\ld h a temp]ature ( #cb & no m4 ,?is is a fact exactly p>allel to t :i* is obs]v$ :5 wat] is rais$ to ! boil+-po9t4 ,s long z any ( ! wat] rema9s unconv]t$ into /eam x becomes no hott]4 ,moreov] ! /eam itself is at fir/ at #bab4 #dd4 ,ice ! solid1 ,wat] ! liquid1 & ,/eam ! gas1 are ?ree /ates ( "o natural object2 ! ,condition ( ea* ,/ate be+ a c]ta9 ,am\nt ( ,heat4 ,ice1 liquid wat]1 & /eam1 are ?ree ?+s z unlike z any ?ree ?+s c well be4 ,:at d we mean !n by say+ t !y are /ates ( "o sub/ance1 wat]8 ,:at we really mean is t if we take a giv5 quantity ( wat]1 say a cubic in*1 & *ange x fir/ into ice & !n into /eam1 !re is some?+ :i* rema9s id5tically ! same ?r\gh all ^! *anges4 ,?is some?+ is1 9 ! fir/ place1 ! weight ( ! mat]ial sub/ance4 ,! wat] weighs #beb gra9s1 ! ice into :i* x is conv]t$ weighs #beb gra9s1 & ! /eam produc$ f x weighs #beb gra9s4 ,9 ! second place1 ! same =ce w\ld cause ! ice1 ! wat]1 & ! /eam1 to move ) ! same rapidity2 &1 :5 set 9 motion1 !y w\ld produce ! same effect ^u any?+ movable aga9/ :i* !y /ruck4 ,9 ! ?ird place1 :5 y /udy *emi/ry1 y w le>n t ! ice1 ! /eam1 & ! liquid wat]1 w\ld yield ! same weight ( ! same two gases1 oxyg5 & hydrog51 & no?+ else4 ,e "o cubic in* ( wat]1 #a1gjj cubic in*es ( /eam1 & #a_/aaa cubic in* ( ice1 yield #bha_/ah gra9s ( hydrog51 ) #bbdh_/ah gra9s ( oxyg51 & no?+ else4 7,see #ej47 ,z !re is n ! slighte/ diff]5ce 9 weight betwe5 a giv5 quantity ( wat] & ! ice1 or ! /eam1 into :i* x may be conv]t$1 x is cle> t ! heat :i* is add$ to or tak5 f ! wat] to give rise to ^! sev]al /ates1 c possess no weight4 ,if !n heat is a mat]ial body1 x mu/ be devoid ( weight--& h5ce1 9 =m] times1 heat 0 call$ an impond]able sub/ance4 ,x 0 ?\ght to be a k9d ( fluid1 call$ caloric1 :i* _h no weight1 & :i* drove ! p>ticles ( bodies asund]1 :5 x ent]$ !m z !y 7 heat$1 & let !m come toge!r z x left & !y grew cool4 #de4 ,! ,ph5om5a ( ,heat are ! ,effects ( a rapid ,motion ( ! ,p>ticles ( ,matt]4 ,?is mu*1 h[ev]1 is c]ta93 t heat c be caus$ by motion4 ,e boy kn[s t a metal button may be made q hot by rubb+ x4 ,a skilful smi? w hamm] a piece ( iron r$ hot4 ,! axles ( :eels become r$ hot by rubb+ aga9/ _! be>+s1 if !y are n prop]ly lubricat$2 & ev5 two pieces ( ice may be melt$ by ! heat evolv$ :5 !y are rubb$ toge!r4 ,& !re are abundant o!r reasons1 z y w f9d :5 y /udy physics1 = ! belief t ! s5sation we call heat1 & all ! ph5om5a :i* we ascribe to heat1 are ! effects ( ! rapid motion ( matt]4 ,h[ev]1 a quiesc5t body may be made hot )\t exhibit+ ! lea/ appe>ance ( motion4 ,! surface ( ! wat] 9 a tumbl] at #ajj is j z unruffl$ z t ( ! same wat] at #cb4 ,:at1 !n1 is meant by say+ t heat is a k9d ( motion1 & t ! great] ! heat 9 any body ! great] ! am\nt ( motion 9 t body8 ,! answ] to ?is "q is t ! motion :i* causes ! ph5om5a ( heat1 is n a visible motion ( ! :ole mass ( ! hot body1 b a motion ( ! individual p>ticles ( :i* x is compos$4 ,& ea* p>ticle moves1 n /raight =w>d1 b backw>ds & =w>ds 9 ! same space1 s t its motion may be r\ghly comp>$ to t ( a p5dulum1 or to t ( ! balance-:eel ( a wat*4 ,x is 9 fact a sort ( vibratory movem5t2 ea* vibration tak+ place ?r\gh a v %ort di/ance & ) extreme rapidity4 ,! s5sation ( heat is caus$ by ! vibratory movem5ts ( ! p>ticles ( matt]1 j z s\nd is s caus$4 ,! prongs ( a tun+-=k :i* has be5 /ruck1 c]ta9ly vibrate1 = y c see !m d s if ! note is l[4 ,if y n[ put y\r e> at "o end ( a long piece ( timb] & ! h&le ( ! vibrat+ tun+-=k is plac$ ^u ! o!r end1 ! vibratory motion ( ! tun+-=k w be communicat$ to ! p>ticles ( ! wood & w be l\dly he>d4 ,all ! "t ! s\nd is he>d ! p>ticles ( ! wood are vibrat+4 ,nev]!less1 ! wood z a :ole does n move1 b its p>ticles sw+ backw>ds & =w>ds ?r\gh su* a m9ute space t _! motion is imp]ceptible4 ,b :at are ^! p>ticles ( matt] :i* by _! vibration give rise to ! ph5om5a ( heat8 #df4 ,! ,/ructure ( ,wat]4 ,we h se5 t pure wat] is p]fectly cle> & transp>5t4 ,! nak$ eye c disc]n no diff]5ce betwe5 "o "p & ano!r4 ,9 o!r words1 x has no visible texture or /ructure4 ,x does n foll[ t x really possesses none1 h[ev]1 = !re are _m ?+s :i* seem to be ! same ?r\gh\t1 or homog5e\s1 :i* yet %[ /ructure if !y are exam9$ ) a magnify+ glass4 ,?us ! surface ( a %eet ( f9e :ite pap] looks p]fectly ev5 & smoo? to ! eye2 b a magnify+ glass ( no great p[] w %[ ! m9ute woody fibres ( :i* x is made up2 :ile1 "u a p[]ful microscope1 ! pap] looks l a co>se matt+4 ,b if we put a small drop ( wat] on a slide1 su* z is us$ = microscopic objects1 & cov] x ov] ) a ?9 glass s z to spread x out into a film1 p]haps n m ?an #a_/ajjjj? ( an in* ?ick1 x may be exam9$ ) ! v highe/ magnify+ p[]s we c comm&1 & yet x looks z completely homog5e\s & %[s z little evid5ce ( be+ made up ( sep>ate p>ts z be=e4 ,h[ev]1 ?is is /ill no pro( t ! wat] is n made up ( little p>ts1 or p>ticles1 di/9ctly sep>at$ f "o ano!r4 ,x may m]ely mean t ! p>ticles are s extremely small t !y _c be di/+ui%$ ev5 by microscopes :i* magnify f\r or five ?\s& diamet]s4 ,x is c]ta9 t solid bodies may be divid$ into p>ticles s m9ute t ! be/ microscopes %[ no trace ( !m4 ,common gum-ma/ic _c be dissolv$ by wat]1 b x readily dissolves 9 /rong _s or alcohol1 & ma/ic v>ni% is an alcoholic solution ( gum-ma/ic4 ,if y add wat] to ma/ic v>ni%1 ! alcohol takes away ! wat] & ! ma/ic falls out1 or precipitates1 z a curdy solid compos$ ( v visible :iti% p>ticles4 ,b if a drop ( ! v>ni% is add$ to a good deal1 say half a p9t1 ( wat] & well /irr$ at ! same "t1 ! ma/ic1 ?\gh x is /ill precipitat$ z a solid1 is 9 a /ate ( extremely m9ute division4 ,no sep>ate solid p>ticles ( ma/ic are visible to ! nak$ eye1 b ! wat] assumes a fa9t milky t+e4 ,?is milk9ess arises f ! pres5ce ( solid p>ticles ( ma/ic diffus$ ?r\gh ! wat]2 & yet1 if ! exp]im5t has be5 prop]ly manag$1 a drop ( ! fluid may be spread out z be=e & exam9$ ) ! highe/ magnify+ p[]s1 & no?+ c be se5 ( su* p>ticles4 ,s f> z vision goes x might be a drop ( pure wat]4 ,n[ our be/ microscopes are able to %[ u any?+ solid :i* has a diamet] ( #a_/ajjjjj? ( an in*1 q di/9ctly2 & probably solid opaque p>ticles ( mu* small] size w\ld make !mselves app>5t z a turbidity or cl\d9ess4 ,! p>ticles ( ma/ic mu/ be !re=e s mu* small] ?an ?is t !y rema9 invisible4 ,h5ce x foll[s t if wat] 7 made up ( sep>ate p>ticles1 or droplets1 #a_/ajjjjjj? ( an in* 9 diamet]1 & ?us _h ! /ructure ( a mass ( v f9e %ot1 no microscope t has yet be5 con/ruct$ w\ld enable u to see ev5 a trace ( t /ructure4 ,we c\ld n obta9 any direct evid5ce ( x4 #dg4 ,suppositions or ,hypo!ses2 _! ,uses & _! ,value4 ,:5 our means ( obs]vation ( any natural fact fail to c>ry u beyond a c]ta9 po9t1 x is p]fectly legitimate1 & (t5 extremely useful1 to make a supposition z to :at we %\ld see1 if we c\ld c>ry direct obs]vation a /ep fur!r4 ,a supposition ( ?is k9d is :at is call$ a hypo!sis1 & ! value ( any hypo!sis dep5ds ^u ! ext5t to :i* reason+ ^u ! assumption t x is true1 enables u to expla9 or acc\nt = ! ph5om5a ) :i* x is conc]n$4 ,?us1 if a p]son is /&+ close beh9d y1 & y sudd5ly feel a bl[ on y\r back1 y h no direct evid5ce ( ! cause ( ! bl[2 & if y two 7 alone1 y c\ld n possibly obta9 any2 b y imm$iately suppose t ?is p]son has /ruck y4 ,n[ t is a hypo!sis1 & x is a legitimate hypo!sis1 fir/1 because x expla9s ! fact2 &1 secondly1 because no o!r explanation is probable2 probable mean+ 9 accordance ) ! ord9>y c\rse ( nature4 ,if y\r companion decl>$ t y fanci$ y felt a bl[1 or t "s invisible _s /ruck y1 y w\ld probably decl9e to accept 8 explanation ( ! fact4 ,y w\ld say t bo? ! hypo!ses by :i* he pr(ess$ to expla9 ! ph5om5on 7 extremely improbable2 or 9 o!r words1 t 9 ! ord9>y c\rse ( nature fancies ( ?is k9d d n occur1 nor spirits /rike bl[s4 ,9 fact1 8 hypo!ses w\ld be illegitimate1 & y\rs w\ld be legitimate2 &1 9 all probability1 y w\ld act ^u y\r own4 ,9 daily life1 n9e-t5?s ( our actions are bas$ ^u suppositions or hypo!ses1 & our success or failure 9 practical affairs dep5ds ^u ! legitimacy ( ^! hypo!ses4 ,y believe a man on ! hypo!sis t he is always tru?ful2 y give him pecuni>y cr$it on ! hypo!sis t he is solv5t4 ,?us1 ev]ybody inv5ts1 &1 inde$1 is compell$ to inv5t1 hypo!ses 9 ord] to acc\nt = ph5om5a ( ! cause ( :i* he has no direct evid5ce2 & !y are j z legitimate & necess>y 9 sci5ce z 9 common life4 ,only ! sci5tific reason] mu/ be c>eful to rememb] t :i* is sometimes =gott5 9 daily life1 t a hypo!sis mu/ be reg>d$ z a means & n z an end2 t we may *]i% x s long z x helps u to expla9 ! ord] ( nature2 b t we are b\nd to ?r[ x away )\t hesitation z soon z x is %[n to be inconsi/5t ) any "p ( t ord]4 #dh4 ,! ,hypo!sis t ,wat] is compos$ ( ,sep>ate ,p>ticles 7,molecules74 ,x has be5 po9t$ out t we _c see1 & inde$ t !re is n mu* hope ( our ev] be+ able to see1 ! sep>ate p>ticles ( wat]1 ev5 if wat] is compos$ ( su* p>ticles4 ,b x is p]fectly legitimate to suppose t wat] is made up ( su* p>ticles1 if t hypo!sis w enable u to expla9 ! prop]ties ( wat]4 ,let u suppose !n t any portion ( fluid wat] is really compos$ ( a prodigi\s numb] ( p>ticles less 7& probably mu* less7 ?an a million? ( an in* 9 diamet]4 ,we may call ^! p>ticles molecules4#d ,footnote #d3 ,dim9utive ( moles1 a mass4 ,we are ju/ifi$1 9 accordance ) ! g5]al prop]ties ( matt] 7 #ah71 9 suppos+ t ^! molecules t5d to approa* "o ano!r4 ,b ! fact t wat] is slightly compressible ju/ifies ! supposition t its molecules are n 9 actual contact1 b t !y are sep>at$ by int]spaces1 j z ! motes 9 ! air ( a du/y room are s sep>at$4 ,:at is x t keeps ! molecules ap>t8 ,we h se5 t great me*anical pressure br+s !m b slightly ne>] to "o ano!r2 h5ce !re is an equival5t resi/ance ( "s k9d :i* keeps !m ap>t4 ,?is resi/ance mu/ h ! same orig9 z ! s5sation :i* we "k z heat1 = x has be5 se5 t dim9ution ( heat dim9i%es ! bulk ( wat]2 t is1 all[s ! molecules to come clos] toge!r2 t is1 dim9i%es _! t5d5cy to keep asund]4 ,increase ( heat1 on ! o!r h&1 increases ! volume ( wat]2 t is to say1 drives ! molecules fur!r ap>t1 or increases _! t5d5cy to keep asund]4 ,suppose we call ! cause ( ! t5d5cy ( ! molecules ( wat] to come toge!r an attractive =ce2 & ! cause ( _! keep+ ap>t1 :i* manife/s itself to u z ! s5sation ( heat & is1 z we h se51 9 all probability1 a rapid vibratory or :irl+ motion ( ! molecules1 a repulsive =ce2 !n1 9 ! liquid /ate1 ^! =ces are s adju/$ t ! molecules are q free to move1 & yet hold toge!r4 ,by add+ heat ! repulsive =ce is increas$1 until ! molecules are ab\t twelve times z f> ap>t z !y 7 9 ea* direction2 :ile ! attractive =ce is ov]come1 & ! molecules fly (f 9 all directions z soon z !y are unconf9$4 ,on ! o!r h&1 by tak+ heat away1 ! repulsive =ce is dim9i%$1 until ! molecules become insep>able & ! wat] assumes ! solid =m4 ,x is probable t ! expansion ( fluid wat]1 at a temp]ature bel[ #ci1 dep5ds ^u ! molecules tak+ up a peculi> arrangem5t z !y approa* "o ano!r4 ,if sixte5 m5 are =m$ into a column1 f\r deep1 & ea* man a foot f ! o!r1 ! same m5 may /& clos] toge!r & yet =m a holl[ squ>e1 :i* occupies a l>g] space4 ,t ! molecules ( wat] d take up a p>ticul> ord] 9 assum+ ! solid condition1 is %[n by ! cry/all9e =m ( ice4 ,ea* cry/al ( ho>-fro/ owes its %ape to ! arrangem5t ( its molecules1 accord+ to a def9ite geometrical patt]n4 ,?us ! hypo!sis t wat] is compos$ ( sep>ate molecules1 is useful1 = x helps u to "s ext5t to expla9 ! prop]ties ( wat]4 ,&1 :5 y /udy physics & le>n ! laws ( motion1 y w f9d t !re is no end to ! numb] ( ! tru?s e/abli%$ by obs]vation & exp]im5t1 :i* c be expla9$ by ?is hypo!sis4 ,h5ce x may fairly be adopt$ & employ$ z a means ( pictur+ to ourselves ! ord] ( nature1 s long z no facts are discov]$ :i* are inconsi/5t ) x4 #di4 ,all ,matt] is probably made up ei!r ( ,molecules or ( ,atoms4 ,! same reasons :i* lead to ! adoption ( ! hypo!sis t wat] is compos$ ( sep>ate p>ticles ju/ify its ext5sion to all =ms ( matt] :atev]4 ,! metal m]cury or quicksilv]1 = in/ance1 may be suppos$ to be made up ( di/9ct p>ticles ( m]cury ( extreme m9ut5ess1 & accord+ to ! temp]ature1 ^! associate !mselves 9 ! solid 7froz5 m]cury71 liquid 7ord9>y quicksilv]71 or gase\s =m 7vap\r ( m]cury74 ,to :atev] treatm5t pure m]cury may be subject$1 we _c get any?+ b m]cury out ( x4 ,! p>ticles ( m]cury h nev] be5 brok5 up4 ,h5ce !y are g5]ally t]m$ atoms1 or p>ticles t _c be divid$2 & m]cury is said to be an elem5t1 or a sub/ance :i* is n comp\nd$ ( any o!r sub/ances4 ,"h is a case 9 :i* x is v useful to di/+ui% betwe5 fact & hypo!sis4 ,! matt] ( fact is t1 up to ! pres5t "t1 no "o has be5 able to get out ( pure m]cury any?+ b pure m]cury4 ,! /atem5t t m]cury is a simple sub/ance1 & !re=e nev] c be brok5 up into any o!r sub/ances1 is a hypo!sis :i* future obs]vation & exp]im5t may or may n confirm4 ,a hundr$ & fifty ye>s ago x 0 univ]sally believ$ t wat] 0 z mu* an elem5t z m]cury4 ,b wat] is n[ well kn[n to be a comp\nd4 ,9 fact1 z has already be5 said1 ! p>ticles ( wat] may be v readily brok5 up or decompos$ 79 :at way1 y w le>n :5 y /udy *emi/ry7 into two totally di/9ct sub/ances1 oxyg5 & hydrog51 :i* are gase\s at all kn[n temp]atures1 ?\gh by comb9+ va/ pressure ) extreme cold !y h rec5tly be5 liquefi$4 ,ea* ( ^! gases1 accord+ to our hypo!sis1 consi/s ( p>ticles1 & s9ce ^! c by no kn[n means be fur!r brok5 up1 !y are consid]$ to be atoms l ^? ( m]cury4 ,n9e p>ts by weight ( pure wat] always yield eight ( oxyg5 & "o ( hydrog54 ,! hypo!tical p>ticle1 or molecule ( wat]1 !re=e1 mu/ be compos$ ( atoms ( oxyg5 & hydrog5 hav+ ?is relative weight2 & *emi/s h gr\nds = believ+ t "o atom ( oxyg5 & two atoms ( hydrog5 exi/ 9 ea* molecule ( wat]4 ,if ?is be s1 ! /ructure ( wat] mu/ be m complicat$ ?an we ?\ght at fir/2 & ea* p>ticle ( wat] 7! molecule7 mu/ be a sy/em compos$ ( ?ree sep>ate atoms4 #ej4 ,elem5t>y ,bodies are nei!r de/roy$ nor is _! ,quantity increas$ 9 ,nature4 ,x has be5 se5 t :5 a cubic in* ( wat] is dissipat$ by heat1 x is n de/roy$1 b t x m]ely *anges its =m f ! fluid to ! gase\s /ate1 :ile its weight rema9s unalt]$4 ,if ! same cubic in* ( wat] is decompos$ into oxyg5 & hydrog5 gases1 ! wat] is inde$ de/roy$1 b ! matt] ( :i* x consi/$ rema9s un*ang$ 9 weight4 ,if ! wat] weigh$ #bebe gra9s1 ! oxyg5 gas w weigh #bbdde gra9s & ! hydrog5 gas w weigh #bhje gra9s4 ,& no?+ t man has be5 able to d has affect$ ! weight ( a giv5 quantity ( ei!r ( ^! gases4 ,s f> z we "k1 elem5t>y bodies reta9 _! weight "u all circum/ances1 & c be trac$ by x :atev] %ape !y may take4 ,if ?is is true x foll[s t1 9 ! ord] ( nature1 matt] is inde/ructible3 ! quantity ( x nei!r increases nor dim9i%es4 ,h5ce x foll[s t natural ?+s & artificial ?+s resemble "o ano!r 9 "o respect4 ,x is true ( bo? t ! matt] ( :i* !y are compos$ is nev] de/roy$ & nev] increas$2 & !re=e ! ord] ( ev5ts 9 nature z mu* consi/s 9 ! jo9+ toge!r & putt+ ap>t ( natural bodies by natural ag5cies1 z ! ord] ( ev5ts 9 ! artificial _w consi/s 9 ! jo9+ toge!r & ! putt+ ap>t ( natural bodies by human ag5cies4 #ea4 ,simple ,mixture4 ,9 ord] to le>n ! mann] 9 :i* wat] may be brok5 up into its elem5ts or decompos$1 y mu/ turn to ! ,prim] on ,*emi/ry4 ,b z a prelim9>y to ! /udy ( t sci5ce1 x may be useful to consid] "s simple cases ( composition & decomposition :i* are exemplifi$ by wat]4 ,if half a p9t ( wat]1 col\r$ by putt+ a little ink into x1 is add$ to ! same quantity ( clean wat]1 ! two w readily m+le2 ! total quantity ( wat] w be a p9t2 & its col\r w be j half z d>k z t ( ! col\r$ half-p9t4 ,?is is a case ( simple mixture4 ,! volume ( ! mixture equals ! sum ( ! volumes ( ! ?+s mix$1 & !re is no *ange 9 ! prop]ties ( ^! ?+s4 ,s :5 wat] evaporates1 ! gase\s wat] or vap\r mixes ) ! air 9 ! same way1 ! molecules ( ! "o body disp]s+ !mselves betwe5 ! molecules ( ! o!r until !re is ! same proportion ( ea* ev]y:]e4 ,9 l mann]1 s& & sug> may be 7& un=tunately (t5 are7 mix$1 )\t any *ange 9 ! prop]ties ( ei!r1 or 9 ! space :i* !y primitively occupi$4 ,on ! o!r h&1 oil & wat] w n mix1 h[ev] mu* y may /ir ! two toge!r2 & ! oil1 be+ ! light]1 rises to ! top z soon z ! fluid is quiet4 ,nor w quicksilv] & wat] mix1 b ! quicksilv]1 be+ v mu* heavi] ?an ! wat]1 ru%es to ! bottom ( ! vessel into :i* ! two are put4 ,nei!r w s& nor iron fil+s mix ) wat]2 z heavi] bodies1 !y also s9k to ! bottom4 ,nor does p[d]$ ice1 ?\gh x is wat] 9 ano!r %ape1 mix ) ice cold wat]2 z a light] body x floats at ! top4 #eb4 ,mixture foll[$ by ,increase ( ,d5sity2 ,alcohol & ,wat]4 ,/rong _s1 or alcohol1 is a cle> transp>5t fluid :i* looks l wat]1 b is a v diff]5t sub/ance4 ,= example1 x boils at a mu* l[] temp]ature1 x burns ) a blue flame1 x has intoxicat+ prop]ties1 &1 l oil1 x is v mu* light] ?an wat]4 ,h5ce1 if col\r$ _s is p\r$ g5tly ^u ! surface ( wat] ! _s re/s ^u ! wat]4 ,suppose1 n[1 t we take a tall measure graduat$ into t5 equal p>ts4 ,fill ! l[] five ) wat]1 & !n1 v g5tly1 p\r 9 ! /ronge/ alcohol1 col\r$ 9 "s way1 until ! t5? m>k is rea*$4 ,we %all h five volumes ( wat] bel[1 & an equal quantity1 or five volumes1 ( col\r$ alcohol above4 ,:]e ! two are 9 contact1 ! col\r w be diffus$ into ! wat] = a %ort di/ance1 b n f>1 %[+ t only a slight mixture is tak+ place4 ,?is1 h[ev]1 is n because ! two fluids m+le ) difficulty2 =1 ) slight /irr+1 !y mix completely1 & y h a fluid ! col\r ( :i* is ab\t half z int5se z t ( ! alcohol1 & _m ( ! o!r prop]ties ( :i* are int]m$iate betwe5 ^? ( pure alcohol & ^? ( pure wat]4 ,?us f>1 no?+ fur!r ?an simple mixture1 z :5 col\r$ wat] 0 add$ to pure wat]1 seems to h occurr$2 b1 9 reality1 some?+ m has happ5$4 ,9 ! fir/ place1 ! mixture is a good deal w>m] ?an ei!r ( its compon5ts2 t is to say1 heat has be5 g5]at$4 ,9 ! second place1 if y measure ! volume ( ! :ole fluid aft] x has cool$1 x no long] /&s at ! m>k t51 b di/9ctly l[]1 or ab\t n9e & ?ree-qu>t]s4 ,z ! volume ( ! mixture is less ?an ! sum ( ! volumes ( its two compon5ts1 x foll[s t ! d5sity ( ! mixture mu/ be great] ?an a d5sity midway betwe5 t ( ! wat] & t ( ! alcohol4 ,9 o!r words1 ! molecules 9 ! mixture d n occupy ! same space z !y did :5 !y 7 sep>ate4 ,! result is ! same z if ! t5 volumes _h be5 compress$ until !y occupi$ only n9e & ?ree-qu>t]s2 s t ! effect is a contraction simil> to t :i* w\ld be br\ght ab\t by tak+ away heat f ! mixture4 ,9 fact1 z we h se51 ! mixture gives out a quantity ( heat4 ,!re is ano!r respect 9 :i* ! mixture is unlike bo? its con/itu5ts4 ,x bo? boils & freezes at a mu* l[] temp]ature ?an wat] does1 & at a high] temp]ature ?an alcohol does4 ,9 fact pure alcohol has n yet be5 froz54 ,if ! molecules ( ! alcohol 7 m]ely diffus$ among ^? ( ! wat] z wat] is diffus$ ?r\gh wet s&1 !y ought to pass into ! gase\s /ate at ! same temp]ature z t at :i* alcohol boils2 & x w\ld !n be v easy to sep>ate alcohol f wat] by di/illation4 ,b ! fact is n s2 alcohol _c be obta9$ free f wat] by di/illation unless some?+ :i* holds wat] v /rongly1 su* z quicklime1 is add$1 s z to keep all ! wat] back :5 ! fluid is heat$4 ,?us alcohol & wat]1 m+l$ toge!r1 give rise to a fluid :i* is n a m]e mixture1 ! prop]ties ( :i* are kn[n if we "k ! prop]ties ( its compon5ts2 x is1 9 /rictness1 a new body1 9 :i* ! molecules ( ! wat] & ^? ( ! alcohol affect "o ano!r to a c]ta9 ext5t & modify ! pre-exi/+ prop]ties ( ea*4 ,?is effect ( diff]5t bodies ^u "o ano!r becomes mu* m manife/ :5 wat] is br\ght into contact ) c]ta9 solids4 #ec4 ,solution2 ,wat] ,dissolves ,salt4 ,if a spoonful ( salt is put into a tumbl] ( cold wat] & ! wat] is /irr$1 ! salt swiftly vani%es f view2 &1 aft] a "t1 s f> z our s5se ( vision goes1 ! wat] appe>s to be j :at x 0 be=e4 ,b if ! wat] 9 ! tumbl] at fir/ weigh$ five ounces & ! salt weigh$ two ounces1 ! wat] 9 ! tumbl] w n[ weigh sev5 ounces2 ! wat] w n[ ta/e salt1 ! salt is said to be dissolv$1 & ! solution is call$ br9e4 ,moreov]1 ! solution is said to be saturat$1 = if y put m salt 9 x w rema9 un*ang$4 ,wat]1 9 fact1 w dissolve two-fif?s ( its weight ( salt & no m4 ,if ! br9e ?us =m$ is put into a wide di%1 s t ! wat] may evaporate2 or if x is heat$ & ! wat] boil$ away2 z fa/ z ! wat] dim9i%es1 a quantity ( salt1 equal to two-fif?s ( ! wat] :i* is conv]t$ into /eam1 returns to ! solid /ate & falls to ! bottom ( ! vessel4 ,& :5 all ! wat] is driv5 (f1 ! salt :i* rema9s w h exactly ! weight1 & all ! o!r prop]ties :i* x _h be=e x 0 dissolv$ by ! wat]4 ,?us1 contact ) wat] has _h a v s+ul> effect ^u ! salt4 ,x appe>s to h *ang$ "o ( ! prop]ties ( ! salt1 namely1 its solidity1 b to h left all ! re/ unalt]$4 ,we saw j n[ t p[d]$ ice does n mix ) ice-cold wat]1 b t ! fragm5ts ( ice rema9 solid4 ,! mom5t1 h[ev]1 t ! temp]ature rises1 ! cohesion1 or /ick+ toge!r ( ! molecules1 :i* is ! *>act]i/ic ( ! solid /ate1 comes to an end2 !y become loose & free to move1 & !y m+le ) ! surr\nd+ wat]4 ,or we may say t ! ties :i* held ! molecules ( ! solid toge!r are dissolv$1 s t ! solid wat] becomes fluid4 ,! resemblance ( ?is process to ! dissolv+ ( salt 9 wat] is s obvi\s t1 9 common language1 x is (t5 said t a lump ( salt or ( sug> melts away 9 wat]2 b if y try to make salt fluid by heat1 y w h to expose x to a v high temp]ature1 s t ! conv]sion ( salt f ! solid /ate into ! liquid /ate by solution 9 cold wat] is obvi\sly a v diff]5t process f liquefaction by heat4 ,nev]!less ! result is ! same s f> z ! condition ( ! salt is conc]n$4 ,! cohesion betwe5 its molecules is de/roy$1 & !y di/ribute !mselves ev5ly among ! molecules ( ! wat]1 j z ! molecules ( /eam di/ribute !mselves among ! molecules ( air4 ,&1 :5 y /udy *emi/ry1 y w le>n h[ x may be prov$ t ! smalle/ drop ( ! solution ( salt conta9s exactly ! same proportion ( salt z ! :ole does4 ,if br9e is all[$ to evaporate sl[ly1 ! molecules ( ! salt arrange !mselves1 z ! wat] leaves !m1 9 beautifully regul> cubical cry/als4 ,y may see !m =m easily en\gh if y wat* a drop ( br9e gradually dry up "u a microscope4 ,! salt cry/als conta9 no?+ b salt4 ,if !y are heat$ till !y become r$-hot !y pass into ! fluid /ate2 & :5 /ill fur!r heat$1 ! fluid salt becomes a vap\r or gas &1 z su*1 flies (f into ! air1 or volatilizes4 ,?us we see t :5 salt & wat] are br\ght into contact1 ! salt und]goes a c]ta9 am\nt ( *ange1 :ile ! wat] does n rema9 :olly un*ang$4 ,= br9e no long] boils at #bab1 b requires a consid]ably high] temp]ature4 ,! salt1 z x 71 holds ! wat] back1 & prev5ts x f assum+ ! gase\s /ate "u ! same conditions z if x 7 pure1 j z1 9 ! previ\s case1 ! wat] held ! alcohol back2 or we may say t ! =ce ( heat :i* drives ! molecules ( liquid wat] ap>t1 :5 /eam is =m$1 has a great] resi/ance to ov]come :5 salt is dissolv$ 9 ! wat]4 ,& j z ! pres5ce ( alcohol l[]s ! freez+ po9t ( ! wat] ) :i* x is mix$1 s does ! pres5ce ( salt l[] ! freez+ po9t ( wat]4 ,sea wat]1 :i* is a weak br9e1 beg9s to freeze at ab\t #bg2 & ! ice :i* is =m$ is q pure1 :ile ! rema9d] ( ! sea wat] becomes ri*] 9 salt4 ,if we mean by attraction t :i* opposes any =ce :i* t5ds to sep>ate bodies1 !n we may say t ! molecules ( salt & ^? ( wat] attract "o ano!r4 ,& su* attraction betwe5 molecules ( matt] ( diff]5t k9ds is call$ *emical attraction4 #ed4 ,quicklime & ,wat]3 ,pla/] ( ,p>is & ,wat]3 ,comb9ation4 ,quicklime is a sub/ance obta9$ by heat+ *alk or lime/one to r$ness4 ,:5 pure1 x is a :ite h>d solid :i* c be made to pass into ! liquid & gase\s /ates only at enorm\sly high temp]atures4 ,if a lump ( fre% quicklime be plac$ 9 a sauc] & ab\t "o-?ird ( its weight ( wat] p\r$ ^u x1 !re w be a great turmoil1 heat w be evolv$1 ! wat] w disappe>1 & ! lime w crumble d[n into a s(t :ite p[d]4 ,?is op]ation is :at bricklay]s call slak+ lime4 ,& if no m wat] has be5 add$ ?an ! proportion m5tion$1 ! pure :ite p[d] :i* results w be solid & dry1 ! wat] hav+1 to all appe>ance1 vani%$4 ,9 ! solution ( salt we saw a solid become fluid "u ! influ5ce ( wat]2 9 ! slak+ ( lime ! fluid wat] ent]s into ! /ructure ( a solid4 ,if m wat] is add$1 ?is solid dissolves or becomes liquid1 z ! salt did1 & ! solution is call$ limewat]4 ,by c>efully manag$ evaporation ( ! wat] ! lime may be recov]$ 9 ! =m ( cry/als1 j z ! salt 0 recov]$4 ,b !re is ?is diff]5ce1 t ! salt cry/als conta9 no wat]1 :ile ! lime cry/als n only conta9 wat]1 b conta9 exactly ! same proportion z exi/s 9 slak$ lime1 t is to say1 #ah p>ts wat] to #ef p>ts lime4 ,! wat] ?us b\nd up ) ! lime into a new solid holds on s firmly to ! lime t x requires a r$ heat to sep>ate ! two4 ,! lime & ! wat] are said to be *emically comb9$2 & z ! proportion ( lime & wat] 9 slak$ lime1 or lime cry/als1 is always ! same1 !y are said to be comb9$ 9 def9ite proportions2 & ! slak$ lime receives ! special "n ( hydrate ( lime4 ,gypsum or ,pla/] ( ,p>is is a dry :ite p[d]4 ,if mix$ ) a little wat] x does n slake aft] ! fa%ion ( quick lime1 b ! mixture soon sets or becomes h>d2 &1 at ! same "t1 ! great] "p ( ! wat] disappe>s4 ,9 fact1 x has comb9$ ) ! pla/] ( ,p>is & =ms "p ( ano!r hydrate1 9 :i*1 :5 ! sup]flu\s moi/ure dries1 n a trace ( wat] is to be se54 ,x is ?is prop]ty :i* is tak5 advantage ( :5 pla/] ( ,p>is is us$ 9 mak+ ca/s & m\lds4 ,! fluid pla/] is p\r$ ov] & r\nd ! body to be ca/2 z a fluid1 x applies itself conv5i5tly to all ! inequalities ( its surface2 &1 :5 x sets1 x reta9s ! %ape :i* x has ?us acquir$4 ,set pla/] ( ,p>is may be p]fectly dry2 b x nev]!less conta9s betwe5 & ( its weight ( wat]1 fix$ & =m+ an integral "p ( ! solid hydrate4 ,& if ! set pla/] is /rongly heat$1 ! comb9$ wat] is driv5 (f & x returns to its orig9al /ate4 ,gypsum is f\nd abundantly 9 nature1 9 ! %ape ( beautiful transp>5t cry/als :i* are call$ sel5ite4 ,^! cry/als h ! same composition z set pla/]1 t is to say1 !y are hydrates4 ,a ?9 flake ( su* a cry/al view$ ) ! highe/ p[]s ( ! microscope appe>s p]fectly homog5e\s4 ,nev]!less1 !re is good reason = ! conclusion t x consi/s ( molecules ( wat] & molecules ( gypsum :i* hold toge!r s /rongly t !y =m a h>d brittle glassy solid4 ,moreov]1 ! molecules ( ! hydrate itself hold toge!r m /rongly 9 "s directions ?an 9 o!rs4 ,x is v easy to split ! cry/als l5g?wise2 :ile mu* m =ce is ne$$ to cut !m crosswise & !n !y d n split1 b break4 ,glaub]'s salts & ,epsom salts are o!r examples ( solids :i* dissolve 9 wat] & sep>ate 9 ! cry/all9e =m z ! wat] evaporates2 & :i*1 l lime & gypsum1 comb9e ) a def9ite proportion ( wat] to =m cry/all9e comp\nds4 ,9 fact1 ea* ( ^! glassy brittle solids conta9s m ?an half its weight ( wat]4 ,?us we see t two bodies1 ( :i* wat] is "o1 may comb9e toge!r to give rise to some?+ diff]5t f ei!r4 ,& we are ?us l$ to ! sci5ce ( *emi/ry1 :i* tells u exactly h[ bodies comb9e1 :at comes ( _! comb9ation1 & h[ comp\nds may be sep>at$ into _! con/itu5ts4 #ee4 ,m9]al bodies may take on def9ite %apes & gr[1 or increase 9 size1 by ! addition ( l p>ts4 ,wat] & all ! o!r natural bodies :i* h hi!rto be5 m5tion$1 are :at are call$ m9]al bodies1 al?\gh1 9 common use1 ! t]m m9]al is usually re/rict$ to ores & metals4 ,n[ we h repeat$ly _h occasion to rem>k t1 "u c]ta9 circum/ances1 n only wat]1 b _m o!r m9]al bodies1 assume regul> %apes4 ,! mo/ famili> example is t ( ! beautiful imitation ( leaves & foliage :i* is pres5t$ by ! ice :i* =ms on a w9d[ 9 w9t]4 ,b we h also se5 t common salt1 lime1 gypsum1 ,glaub]'s salts & ,epsom salts1 also assume ! cry/all9e =m z !y or _! comp\nds ) wat] are deposit$ f _! solutions4 ,& if a drop ( solution ( ,glaub]'s salts or ( ,saltpetre1 is all[$ to evaporate "u ! microscope1 a wond]ful spectacle w be pres5t$4 ,z ! salt assumes ! solid /ate1 ! cry/als sudd5ly appe> 9 ! field ( view z ne$les & plates dispos$ 9 beautiful patt]ns1 :i* rival ^? ( ho> fro/1 ?\gh !y are q diff]5t f !m4 ,9 fact1 z y w le>n if y /udy cry/allography1 e cry/allizable sub/ance has its prop] cry/all9e =ms & nev] dep>ts f c]ta9 /rictly relat$ geometrical figures4 ,a cry/al ( any ( ^! sub/ances w gr[ if plac$ "u prop] conditions4 ,?us1 if a cry/al ( common salt is hung by a ?read 9 a saturat$ solution ( salt1 :i* is expos$ to ! air1 s z to all[ ! wat] to evaporate sl[ly1 ! molecules ( ! salt :i* is left beh9d & c no long] be held 9 solution1 deposit !mselves on ! cry/al 9 regul> ord] & increase its size )\t *ang+ its =m4 ,&1 9 ?is way1 ! small cry/al may gr[ to a great size4 ,! l>ge cry/als ( sug> c&y1 :i* consi/ ( sug> & wat] deposit$ f a /rong syrup or saturat$ solution ( sug>1 gr[ 9 ! same fa%ion1 ^u ?reads susp5d$ 9 ! evaporat+ syrup4 ,9 ?is mode ( gr[? y w obs]ve t ! enl>gem5t is effect$ by addition to ! outside ( ! gr[+ body2 & moreov] ! matt] :i* is add$1 namely1 ! salt or ! sug>1 already exi/s z salt 9 ! br9e or z sug> 9 ! syrup4 ,b4 ,,liv+ ,,bodies4 #ef4 ,! ,:eat ,plant & ! sub/ances ( :i* x is compos$4 ,e "o has se5 a cornfield4 ,if y pluck up "o ( ! innum]able :eat plants :i* are fix$ 9 ! soil ( ! field1 ab\t h>ve/ "t1 y w f9d t x consi/s ( a /em :i* ends 9 a root at "o end & an e> at ! o!r1 & t blades or leaves are atta*$ to ! sides ( ! /em4 ,! e> conta9s a multitude ( oval gra9s :i* are ! se$s ( ! :eat plant4 ,y "k t :5 ^! se$s are cle>$ f ! husk or bran 9 :i* !y are envelop$1 !y are gr\nd into f9e p[d] 9 mills1 & t ?is p[d] is ! fl\r ( :i* bread is made4 ,if a h&ful ( fl\r mix$ ) a little cold wat] is ti$ up 9 a co>se clo? bag1 & ! bag is !n put 9 a l>ge vessel ( wat] & well knead$ ) ! h&s1 x w become pa/y1 :ile ! wat] w become :ite4 ,if ?is wat] is p\r$ away into ano!r vessel1 & ! knead+ process cont9u$ ) "s fre% wat]1 ! same ?+ w happ54 ,b if ! op]ation is repeat$ ! pa/e w become m & m /icky1 :ile ! wat] w be r5d]$ less & less :ite1 & at la/ w rema9 col\rless4 ,! /icky sub/ance :i* is ?us obta9$ by itself is call$ glut52 9 comm]ce x is ! sub/ance kn[n z macc>oni4 ,if ! wat] 9 :i* ! fl\r has ?us be5 wa%$ is all[$ to /& = a few h\rs1 a :ite s$im5t w be f\nd at ! bottom ( ! vessel1 :ile ! fluid above w be cle> & may be p\r$ (f4 ,?is :ite s$im5t consi/s ( m9ute gra9s ( />*1 ea* ( :i*1 exam9$ ) ! microscope1 w be f\nd to h a conc5trically lam9at$ /ructure4 ,if ! fluid f :i* ! />* 0 deposit$ is n[ boil$ x w become turbid1 j z :ite ( egg dilut$ ) wat] does :5 x is boil$1 & ev5tually a :iti% lumpy sub/ance w collect at ! bottom ( ! vessel4 ,?is sub/ance is call$ vegetable album94 ,besides ! album91 ! glut51 & ! />*1 o!r sub/ances1 ab\t :i* ?is r\gh me?od ( analysis gives u no in=mation1 are conta9$ 9 ! :eat gra94 ,= example1 !re is woody matt] or cellulose1 & a c]ta9 quantity ( sug> & fat4 ,x w\ld be possible to obta9 a sub/ance simil> to album91 />*1 sac*>9e & fatty matt]s1 & cellulose1 by treat+ ! /em1 leaves1 & root 9 a simil> fa%ion1 b ! cellulose w\ld be 9 f> l>g] proportion4 ,/raw1 9 fact1 :i* consi/s ( ! dry /em & leaves ( ! :eat plant1 is almo/ :olly made up ( cellulose4 ,besides ?is1 h[ev]1 x conta9s a c]ta9 proportion ( m9]al bodies1 among !m1 pure fl9t or silica2 &1 if y %\ld ev] see a :eat rick burnt1 y w f9d m or less ( ?is silica1 9 a glassy condition1 9 ! emb]s4 ,9 ! liv+ plant1 all ^! bodies are comb9$ ) a l>ge proportion ( wat]1 or are dissolv$1 or susp5d$ 9 t fluid4 ,! relative quantity ( wat] is mu* great] 9 ! /em & leaves ?an 9 ! se$4 #eg4 ,! ,common ,f[l & ! ,sub/ances ( :i* x is ,compos$4 ,ev]ybody has se5 a common f[l4 ,x is an active creature :i* runs ab\t & sometimes flies4 ,x has a body cov]$ ) fea!rs1 provid$ ) two w+s & two legs1 & end+ at "o end 9 a neck t]m9at$ by a head ) a beak1 betwe5 ! two p>ts ( :i* ! m\? is plac$4 ,! h5 lays eggs1 ea* ( :i* is enclos$ 9 a h>d %ell4 ,if y break an egg ! cont5ts fl[ out & are se5 to consi/ ( ! col\rless glairy 8:ite0 & ! yell[ 8yolk40 ,if ! :ite is collect$ by itself 9 wat] & !n heat$ x becomes turbid1 =m+ a :ite solid1 v simil> to ! vegetable album91 :i* is call$ animal album94 ,if ! yolk is beat5 up ) wat]1 no />* nor cellulose is obta9$ f x1 b !re w be pl5ty ( fatty & "s sac*>9e matt]1 besides sub/ances m or less simil> to album9 & glut54 ,! fea!rs ( ! f[l are *iefly compos$ ( horn2 if !y are /ripp$ (f & ! body is boil$ = a long "t1 ! wat] w be f\nd to conta9 a quantity ( gelat91 :i* sets into a jelly z x cools2 & ! body w fall to pieces1 ! bones & ! fle% sep>at+ f "o ano!r4 ,! bones consi/ almo/ entirely ( a sub/ance :i* yields gelat9 :5 x is boil$ 9 wat]1 impregnat$ ) a l>ge quantity ( salts ( lime1 j z ! wood ( ! :eat /em is impregnat$ ) silica4 ,! fle%1 on ! o!r h&1 w conta9 album91 & "s o!r sub/ances :i* are v simil> to album91 t]m$ fibr9 & synton94 ,9 ! liv+ bird1 all ^! bodies are unit$ ) a great quantity ( wat]1 or dissolv$1 or susp5d$ 9 wat]2 & x mu/ be rememb]$ t !re are sundry o!r con/itu5ts ( ! f[l's body & ( ! egg1 :i* are left unm5tion$1 z ( no pres5t importance4 #eh4 ,c]ta9 ,con/itu5ts ( ! ,body are v simil> 9 ! ,:eat ,plant & 9 ! ,f[l4 ,! :eat plant conta9s nei!r horn1 nor gelat91 & ! f[l conta9s nei!r />*1 nor cellulose2 b ! album9 ( ! plant is v simil> to t ( ! animal1 & ! fibr9 & synton9 ( ! animal are bodies closely alli$ to bo? album9 & glut54 ,t !re is a close lik5ess betwe5 all ^! bodies is obvi\s f ! fact t :5 any ( !m is /rongly heat$1 or all[$ to putrefy1 x gives (f ! same sort ( disagreeable smell2 & c>eful *emical analysis has %[n t !y are1 9 fact1 all compos$ ( ! elem5ts ,c>bon1 ,hydrog51 ,oxyg51 & ,nitrog51 comb9$ 9 v ne>ly ! same proportions4 ,inde$1 *>coal1 :i* is impure c>bon1 might be obta9$ by /rongly heat+ ei!r a h&ful ( corn1 or a piece ( f[l's fle%1 9 a vessel f :i* ! air is exclud$ s z to keep ! corn or ! fle% f burn+4 ,& if ! vessel 7 a /ill1 s t ! products ( ?is de/ructive di/illation1 z x is call$1 c\ld be cond5s$ & collect$1 we %\ld f9d wat] & ammonia1 9 "s %ape or o!r1 9 ! receiv]4 ,n[ ammonia is a comp\nd ( ! elem5t>y bodies1 nitrog5 & hydrog52 !re=e 7 #ej7 bo? nitrog5 & hydrog5 mu/ h be5 conta9$ 9 ! bodies f :i* x is d]iv$4 ,x is c]ta91 !n1 t v simil> nitrog5\s comp\nds =m a l>ge "p ( ! bodies ( bo? ! :eat plant & ! f[l1 & ^! bodies are call$ proteids4 #ei4 ,proteid ,sub/ances are met ) 9 ,nature only 9 ,animals & ,plants2 & ,animals & ,plants always conta9 ,proteids4 ,x is a v rem>kable fact t n only are su* sub/ances z album91 glut51 fibr9 & synton91 kn[n exclusively z products ( animal & vegetable bodies2 b t e animal & e plant1 at all p]iods ( its exi/5ce1 conta9s "o or o!r ( !m1 ?\gh1 9 o!r respects1 ! composition ( liv+ bodies may v>y indef9itely4 ,?us1 "s plants conta9 nei!r />* nor cellulose1 :ile ^! sub/ances are f\nd 9 "s animals2 :ile _m animals conta9 no horny matt] & no gelat9-yield+ sub/ance4 ,s t ! matt] :i* appe>s to be ! ess5tial f\ndation ( bo? ! animal & ! plant is ! proteid unit$ ) wat]2 ?\gh x is probable t1 9 all animals & plants1 ^! are associat$ ) m or less fatty & amyloid 7or />*y & sac*>9e7 sub/ances1 & ) v small quantities ( c]ta9 m9]al bodies1 ( :i* ! mo/ important appe> to be phosphorus1 iron1 lime1 & pota%4 ,?us !re is a sub/ance compos$ ( wat] proteids fat amyloids m9]al matt]s :i* is f\nd 9 all animals & plants2 &1 :5 ^! are alive1 ?is sub/ance is t]m$ protoplasm4 #fj4 ,:at is meant by ! ^w ,liv+8 ,! :eat plant 9 ! field is said to be a liv+ ?+2 ! f[l runn+ ab\t ! f>m-y>d is also said to be a liv+ ?+4 ,if ! plant is pluck$ up1 & if ! f[l is knock$ on ! head1 !y soon die & become dead ?+s4 ,bo? ! f[l & ! :eat plant1 z we h se51 are compos$ ( ! same elem5ts z ^? :i* ent] into ! composition ( m9]al matt]1 ?\gh unit$ into comp\nds :i* d n exi/ 9 ! m9]al _w4 ,:y !n d we di/+ui% ?is matt] :5 x takes ! %ape ( a :eat plant1 or a f[l1 z liv+ matt]8 #fa4 ,! ,liv+ ,plant increases 9 size1 by add+ to ! ,sub/ances :i* compose its ,body1 l ,sub/ances2 ^!1 h[ev]1 are n d]iv$ f )\t1 b are manufactur$ )9 ! ,body ( ! ,plant f simpl] ,mat]ials4 ,9 ! spr+1 a :eat-field is cov]$ ) small gre5 plants4 ,^! gr[ tall] & tall] until !y atta9 _m times ! size :i* !y _h :5 !y fir/ appe>$2 & !y produce ! heads ( fl[]s :i* ev5tually *ange into e>s ( corn4 ,9 s f> z ?is is a process ( gr[?1 accompani$ by ! assumption ( a def9ite =m1 x might be comp>$ ) ! gr[? ( a cry/al ( salt 9 br9e3 b1 on clos] exam9ation1 x turns out to be some?+ v diff]5t4 ,= ! cry/al ( salt gr[s by tak+ to itself ! salt conta9$ 9 ! br9e1 :i* is add$ to its ext]ior2 :]eas ! plant gr[s by addition to its int]ior3 & !re is n a trace ( ! *>act]i/ic comp\nds ( ! plant's body1 album91 glut51 />*1 or cellulose1 or fat1 9 ! soil1 or 9 ! wat]1 or 9 ! air4 ,yet ! plant creates no?+ 7 #ej7 &1 !re=e1 ! matt] ( ! proteids & amyloids & fats :i* x conta9s mu/ be suppli$ to x1 & simply manufactur$1 or comb9$ 9 new fa%ions1 9 ! body ( ! plant4 ,x is easy to see1 9 a g5]al way1 :at ! raw mat]ials are :i* ! plant works up1 = ! plant gets no?+ b ! mat]ials suppli$ to x by ! atmosph]e & by ! soil4 ,! atmosph]e conta9s oxyg5 & nitrog51 a little c>bonic acid gas1 a m9ute quantity ( ammoniacal salts1 & a v>iable proportion ( wat]4 ,! soil conta9s clay & s& 7silica71 lime1 iron1 pota%1 phosphorus1 sulphur1 ammoniacal salts1 & o!r matt]s :i* are ( no importance4 ,?us1 betwe5 !m1 ! soil & ! atmosph]e conta9 all ! elem5t>y bodies :i* we f9d 9 ! plant3 b ! plant has to sep>ate !m & jo9 !m toge!r afre%4 ,moreov]1 ! new matt]1 by ! addition ( :i* ! plant gr[s1 is n appli$ to its out] surface1 b is manufactur$ 9 its int]ior2 & ! new molecules are diffus$ among ! old ones4 #fb4 ,! ,liv+ ,plant1 aft] x has gr[n up1 deta*es "p ( its ,sub/ance1 :i* has ! ,p[] ( develop+ into a simil> ,plant1 z a ,se$4 ,! gra9 ( :eat is a "p ( ! fl[] ( ! :eat plant1 :i*1 :5 x becomes ripe1 is easily sep>at$4 ,x conta9s a m9ute & rudim5t>y plant2 &1 :5 x is s[n1 ?is gradually gr[s1 or becomes develop$ into1 ! p]fect plant1 ) its /em1 roots1 leaves & fl[]s1 :i* aga9 give rise to simil> se$s4 ,no m9]al body runs ?r\gh a regul> s]ies ( *anges ( =m & size & !n gives (f p>ts ( its sub/ance :i* take ! same c\rse4 ,m9]al bodies pres5t no su* developm5t & give (f no se$s or g]ms4 ,!y d n reproduce _! k9d4 #fc4 ,! ,liv+ ,animal increases 9 ,size by add+ to ! ,sub/ances :i* compose its ,body1 l ,sub/ances2 ^!1 h[ev]1 are *iefly d]iv$ directly f o!r ,animals or f ,plants4 ,! f[l 9 ! f>m-y>d is incessantly peck+ ab\t & swall[+ n[ a gra9 ( corn1 & n[ a fly or a worm4 ,9 fact1 x is fe$+1 &1 z e "o kn[s1 w\ld soon die if n suppli$ ) food4 ,x is also a matt] ( e day k t x w\ld n be ( mu* use to give a f[l ! soil ( a cornfield1 ) pl5ty ( air & wat]1 to eat4 ,9 ?is respect1 ! f[l is l all o!r animals2 x _c manufacture ! proteid mat]ials ( its body1 b x has to take !m ready made1 or 9 a condition :i* requires b v slight modification1 by dev\r+ ! bodies ei!r ( o!r animals or ( plants4 ,! animal or vegetable sub/ances dev\r$ are tak5 into ! animal's /oma*2 !y are !re dige/$ or dissolv$2 & ?us !y are fitt$ to be di/ribut$ to all p>ts ( ! f[l's own body1 & appli$ to its ma9t5ance & gr[?4 #fd4 ,! ,liv+ ,animal1 aft] x has gr[n up1 deta*es "p ( its ,sub/ance1 :i* has ! ,p[] ( gr[+ into a simil> ,animal1 z an ,egg4 ,! f[l's egg is =m$ 9 ! body ( ! h51 & is1 9 fact1 "p ( h] body inclos$ 9 a %ell & deta*$4 ,x conta9s a m9ute rudim5t ( a f[l2 & :5 x is kept at a prop] temp]ature by ! h5's sitt+ ^u x1 or o!rwise1 = ?ree weeks1 ?is rudim5t gr[s or develops1 at ! exp5se ( ! mat]ials conta9$ 9 ! yolk & ! :ite1 into a small bird1 ! *ick1 :i* is !n hat*$ & gr[s into a f[l4 ,! animal1 !re=e1 is produc$ by ! developm5t ( a g]m 9 ! same way z ! plant2 &1 9 ?is respect1 all plants & all animals agree ) "o ano!r & diff] f all m9]al matt]4 #fe4 ,liv+ ,bodies diff] f ,m9]al ,bodies 9 _! ,ess5tial ,composition1 9 ! mann] ( _! ,gr[?1 & 9 ! fact t !y are reproduc$ by ,g]ms4 ,?us !re is a v broad di/9ction betwe5 m9]al matt] & liv+ matt]4 ,! elem5ts ( liv+ matt] are id5tical ) ^? ( m9]al bodies2 & ! fundam5tal laws ( matt] & motion apply z mu* to liv+ matt] z to m9]al matt]2 b e liv+ body is1 z x 71 a complicat$ piece ( me*anism :i* 8goes10 or lives1 only "u c]ta9 conditions4 ,! g]m conta9$ 9 ! f[l's egg requires no?+ b a supply ( w>m?1 )9 c]ta9 n>r[ limits ( temp]ature1 to build ! molecules ( ! egg into ! body ( ! *ick4 ,& ! process ( developm5t ( ! egg1 l t ( ! se$1 is nei!r m nor less my/]i\s ?an t1 9 virtue ( :i*1 ! molecules ( wat]1 :5 x is cool$ d[n to ! freez+-po9t1 build !mselves up into regul> cry/als4 ,! fur!r /udy ( liv+ bodies leads to ! prov9ce ( ,biology1 ( :i* !re are two great divisions--,botany1 :i* deals ) plants1 & ,zoology1 :i* treats ( animals4 ,ea* ( ^! divisions has its subdivisions--su* z ,morphology1 :i* treats ( ! =m1 /ructure1 & developm5t ( liv+ be+s1 & ,physiology1 :i* expla9s _! actions or functions1 besides o!rs4 ,,iii4 ,,immat]ial ,,objects4 #ff4 ,m5tal ,ph5om5a4 ,mat]ial objects are all ei!r n liv+1 t is to say1 m9]al bodies1 or !y are liv+ bodies4 ,ev]y?+ :i* occupies space1 (f]s resi/ance1 has weight & transf]s motion1 belongs to "o or o!r ( ^! two great prov9ces ( nature4 ,! sci5ces ( ,a/ronomy1 ,m9]alogy1 ,physics1 & ,*emi/ry deal ) ! =m]1 :ile ,biology1 ) its two divisions ( ,zoology & ,botany1 treats ( ! latt]4 ,b natural k is n exhau/$ by ?is catalogue ( its topics4 ,9 ! v fir/ p>agraph ( ?is ,prim]1 9 fact1 we _h occasion to draw a di/9ction betwe5 ,?+s1 or mat]ial objects1 & ,s5sations2 & a mom5t's reflection is suffici5t to conv9ce y t s5sations are n mat]ial objects4 ,a smell takes up no space & has no weight2 & to speak ( a p\nd or ( a cubic foot ( s\nd1 or ( brightness1 is1 on ! face ( ! matt]1 an absurdity4 ,pleasure is said metaphorically to be fugitive1 b y _c imag9e a pleasure z a ?+ 9 motion4 ,:at we call our ,emotions are 9 l mann] devoid ( all ! *>act]s ( mat]ial bodies4 ,love & hatr$1 = example1 _c = a mom5t be conceiv$ to h %ape1 or weight1 or mom5tum4 ,& :51 9 reason+1 we ?9k1 our ,?\ghts h ! same lack ( ! qualities ( mat]ial ?+s4 ,s5sations1 emotions1 & ?\ghts1 ?us con/itute a peculi> gr\p ( natural ph5om5a1 :i* are t]m$ m5tal4 #fg4 ,! ord] ( ,m5tal ,ph5om5a3 ,psy*ology4 ,a def9ite ord] obta9s among m5tal ph5om5a1 j z among mat]ial ph5om5a2 & !re is no m *ance1 nor any accid5t1 nor uncaus$ ev5t1 9 ! "o s]ies ?an !re is 9 ! o!r4 ,moreov]1 !re is a connection ( cause & effect betwe5 c]ta9 mat]ial ph5om5a & c]ta9 m5tal ph5om5a4 ,?us1 = example1 c]ta9 s5sations are always produc$ by ! influ5ce ( p>ticul> mat]ial bodies on our organs ( s5se4 ,! prick ( a p9 gives pa91 fea!rs feel s(t1 *alk looks :ite1 & s on4 ,! /udy ( m5tal ph5om5a1 ( ! ord] 9 :i* !y succe$ "o ano!r1 & ( ! relations ( cause & effect :i* obta9 betwe5 !m & mat]ial ph5om5a1 is ! prov9ce ( ! sci5ce ( ,psy*ology4 ,all ! ph5om5a ( nature are ei!r mat]ial or immat]ial1 physical or m5tal2 & !re is no sci5ce1 except su* z consi/s 9 ! k ( "o or o!r ( ^! gr\ps ( natural objects1 & ( ! relations :i* obta9 betwe5 !m4 ,,! ,,end4 ---------------------------------------- -------------------------------- ,,transcrib]',s ,,notes #a4 ,sil5tly correct$ typographical errors & v>iations 9 spell+4 #b4 ,reta9$ ana*roni/ic1 non-/&>d1 & unc]ta9 spell+s z pr9t$4 #c4 ,footnotes h be5 re-index$ us+ numb]s4 #d4 ,enclos$ italics font 9 und]scores4 #e4 ,enclos$ bold font 9 equals4