,?is file 0 produc$ f images g5]\sly made available by ,! ,int]net ,ar*ive4 ,,liquid ,,drops ,,& ,,globules ,,by ,,! ,,same ,,au?or4 -------------------------------- 99,,pyrometry99 ,a ,practical ,treatise on ! ,measurem5t ( ,high ,temp]atures4 ,) #fj ,illu/rations1 xii #bjj pp4 ,cr[n #hvo1 clo? 7#aiaa74 ,price 99#e_/-99 net4 ---------------- 99,,heat ,,= ,,eng9e]s99 ,a ,treatise on ,heat1 ) special reg>d to its ,practical ,applications4 ,second ,edition ,revis$1 ) #aaj ,illu/rations1 xiv #dcj pp4 ,demy #hvo1 clo? 7#aiab74 ,price 99#ab_/f99 net4 -------------------------------- ,e4 ,f4 ,n4 ,,spon1 ,ltd41 #eg ,haym>ket1 ,london1 ,s4,w4 ,,liquid ,,drops ,,& ,,globules ,_! ,=mation & ,movem5ts ,,?ree ,,lectures ,,deliv]$ ,,to ,,popul> ,,audi5ces ,,by ,,*as4 ,r4 ,,d>l+ ,,associate ,,( ,,! ,,royal ,,college ,,( ,,sci5ce1 ,,irel&2 ,,fell[ ,,( ,,! ,,in/itute ,,( ,,*emi/ry2 ,,fell[ ,,( ,,! ,,physical ,,society1 ,,etc42 ,,lectur] ,,9 ,,physics ,,at ,,! ,,city ,,& ,,guilds ,,( ,,london ,,te*nical ,,college1 ,,f9sbury ,,) #dc ,,illu/rations ,london ,e4 ,f4 ,n4 ,,spon1 ,,limit$1 #eg ,,haym>ket ,,new ,,york ,,spon ,,*amb]la91 #abc ,,lib]ty ,,/reet #aiad ,,cont5ts ,,page ,li/ ( ,illu/rations 4 4 4 4 4 4 4 vii ,preface 4 4 4 4 4 4 4 4 4 ix ,lecture ,i4 ,introduction 4 4 4 4 4 4 4 4 4 #a ,g5]al ,prop]ties ( ,liquids 4 4 4 4 4 4 #b ,prop]ties ( ! ,surface ,sk9 ( ,wat] 4 4 4 4 #c ,ela/ic ,sk9 ( o!r ,liquids-,m9imum ,!rmomet] 4 4 4 #e ,b\nd>y ,surface ( two ,liquids 4 4 4 4 4 4 #f ,area ( ,/ret*$ ,surface 4 4 4 4 4 4 4 #g ,%ape ( deta*$ ,masses ( ,liquid 4 4 4 4 4 #h ,production ( ,true ,sph]es ( ,liquids 4 4 4 4 4 #aj ,! ,c5trifugoscope 4 4 4 4 4 4 4 4 #ad ,effect ( ,temp]ature on ,sph]e ( ,or?otoluid9e 4 4 4 #ae ,o!r ,examples ( ,equi-,d5sity 4 4 4 4 4 4 #ag ,anil9e ,films or ,sk9s 4 4 4 4 4 4 4 #ai ,surface ,t5sion 4 4 4 4 4 4 4 4 #ba ,! ,div+ ,drop 4 4 4 4 4 4 4 4 #bb ,=mation ( ,fall+ ,drops ( ,liquid 4 4 4 4 4 #bd ,asc5d+ or ,inv]t$ ,drops 4 4 4 4 4 4 #ca ,lecture ,,ii4 ,automatic ,anil9e ,drops 4 4 4 4 4 4 4 #cc ,automatic ,drops ( o!r ,liquids4 4 4 4 4 4 #cg ,liquid ,jets 4 4 4 4 4 4 4 4 4 #ch ,liquid ,columns 4 4 4 4 4 4 4 4 #dj ,communicat+ ,drops 4 4 4 4 4 4 4 4 #dd ,comb9$ ,vap\r & ,liquid ,drops 4 4 4 4 4 #dg ,cond5sation ( ,drops f ,vap\r 4 4 4 4 4 #di ,liquid ,cl\ds 9 ,liquid ,m$ia 4 4 4 4 4 4 #ed ,ov]heat$ ,drops 4 4 4 4 4 4 4 4 #ee ,float+ ,drops on ,hot ,surfaces 4 4 4 4 4 4 #eg ,lecture ,,iii4 ,spread+ ( ,oil on ! ,surface ( ,wat] 4 4 4 4 #fj ,movem5ts due to ,solubility 4 4 4 4 4 4 #fc ,movem5ts ( ,anil9e ,globules on a ,wat] ,surface 4 4 4 #fc ,movem5ts ( ,or?otoluid9e & ,xylid9e #a-c-d on a ,wat] ,surface #ff ,production ( ,globules f ,films 4 4 4 4 4 #fh ,network =m$ f a ,film 4 4 4 4 4 4 #gj ,qu9ol9e ,r+s 4 4 4 4 4 4 4 4 #ga ,exp&+ ,globules 4 4 4 4 4 4 4 4 #ga ,attraction betwe5 ,float+ ,globules 4 4 4 4 4 #gc ,analogies ( ,surface ,t5sion ,ph5om5a ) ,life 4 4 4 #ge ,conclusion 4 4 4 4 4 4 4 4 4 #gf ,app5dix ,app>atus & ,mat]ials requir$ = ,exp]im5ts on ,drops & ,globules 4 4 4 4 4 4 4 4 #gh ,index 4 4 4 4 4 4 4 4 4 4 #ha ,,li/ ,,( ,,illu/rations ,,fig4 ,,page #a4 ,silv] %eet float+ on wat] 4 4 4 4 4 #d #b4 ,column & index ( m9imum !rmomet] 4 4 4 #f #c4 ,?read ( gold5 syrup ris+ & =m+ a drop 4 4 #h #d4 ,drops ( diff]5t sizes re/+ on flat plate 4 4 #aj #e4 ,=mation ( a sph]e ( or?otoluid9e 4 4 4 #ab #f4 ,deta*$ sph]e float+ "u wat] 4 4 4 4 #ac #g4 ,! c5trifugoscope 4 4 4 4 4 4 4 #ad #h4 ,anil9e drops fall+ ?r\gh cold wat] & asc5d+ ?r\gh hot wat] 4 4 4 4 4 4 #ag #i4 ,anil9e sk9s envelop+ wat] 4 4 4 4 4 #bj #aj1 #aa1 #ab4 ,! div+ drop4 ,?ree /ages 4 4 4 4 #bc #ac4 ,app>atus = =m+ asc5d+ or desc5d+ drops ( liquids #bg #ad-bj4 ,=mation ( a drop ( or?otoluid9e1 %[+ ! droplet4 ,sev5 /ages 4 4 4 4 4 #bi-ca #ba1 #bb4 ,automatically =m$ anil9e drops1 %[+ ! =mation ( droplets f ! neck 4 4 4 #cd1 #ce #bc-be4 ,jets ( or?otoluid9e dis*>g$ "u wat] 4 4 #ci #bf4 ,wat] /ret*$ betwe5 a tube & a plate 4 4 4 #dj #bg-cj4 ,a liquid column /ret*$ upw>ds by addition ( wat] until brok54 ,f\r /ages 4 4 4 #dc #ca4 ,a column ( aceto-acetic e!r 9 wat] 4 4 4 #dd #cb4 ,app>atus = communicat+ drops 4 4 4 4 #de #cc4 ,comb9$ vap\r & liquid drops 4 4 4 4 #di #cd4 ,sph]oid ( wat] on a hot plate 4 4 4 4 #eh #ce4 ,=ces act+ on a float+ globule 4 4 4 4 #fa #cf4 ,anil9e globules on a wat] surface 4 4 4 4 #fd #cg4 ,or?otoluid9e globules on a wat] surface 4 4 4 #ff #ch4 ,resolution ( a float+ sk9 into globules 4 4 4 #fh #ci4 ,network =m$ f a film ( t>-oil 4 4 4 4 #gj #dj4 ,qu9ol9e r+s & p]=at$ plates 4 4 4 4 #ga #da4 ,! exp&+ globule 4 4 4 4 4 4 #gb #db4 ,! dev\r+ globule4 ,five /ages 4 4 4 #gd #dc4 ,photograph ( "o globule absorb+ ano!r 4 4 4 #ge ,,preface ,! object ( ! pres5t little volume is to reproduce 9 connect$ =m1 an acc\nt ( ! _m int]e/+ ph5om5a associat$ ) liquid drops & globules4 ,mu* ( ! matt] relates to exp]im5ts devis$ by ! au?or dur+ ! pa/ f\r ye>s1 descriptions ( :i* h appe>$ 9 ! ,proce$+s ( ! ,physical ,society2 9 ! columns ( ,nature & ,k2 & else:]e4 ,! exhibition ( ^! exp]im5ts at ! conv]sazioni ( ! ,royal ,society & ! ,royal ,in/itution1 & 9 ! au?or's lectures1 has evok$ su* int]e/ z to sugge/ ! pres5t publication4 ,x may be add$ t all ! exp]im5ts describ$ may be repeat$ by any intellig5t read] at a trifl+ co/1 no special manipulative skill be+ requir$4 ,! context ma9ta9s ! =m ( ! lectures deliv]$ on ?is subject by ! au?or at v>i\s places1 & ! me?od ( pres5tation is su* z may be foll[$ by ^? :o h n receiv$ a tra9+ 9 ?is bran* ( sci5ce4 ,x is hop$1 9 addition1 t ! book may prove ( "s s]vice to tea*]s ( sci5ce & o!rs int]e/$ 9 ! prop]ties ( liquids4 ,a numb] ( ! illu/rations us$ h appe>$ 9 ! pages ( ,k 9 connexion ) ! au?or's articles1 & are "h reproduc$ by c\rtesy ( ! ,editor4 ,o!r draw+s h be5 provid$ by ,mr4 ,w4 ,n>be?1 to :om ! au?or expresses 8 ?anks4 ,,*as4 ,r4 ,,d>l+4 ,city & ,guilds ,te*nical ,college1 ,f9sbury1 #aiad4 ,,liquid ,,drops ,,& ,,globules ,,lecture ,i 99,introduction499--,9 *oos+ a subject = a sci5tific disc\rse1 x w\ld be difficult to f9d any?+ m famili> ?an a drop ( liquid4 ,x might ev5 appe>1 at fir/ sight1 t su* a subject 9 itself w\ld be q inadequate to furni% suffici5t mat]ial = ext5d$ obs]vation4 ,we %all f9d1 h[ev]1 t ! clos] /udy ( a drop ( liquid br+s into view _m int]e/+ ph5om5a1 & provides problems ( great pr(undity4 ,a drop ( liquid is "o ( ! commone/ ?+s 9 nature2 yet x is "o ( ! mo/ wond]ful4 ,ap>t f ! liquids associat$ ) animal or vegetable life1 wat] & petroleum are ! only two :i* are f\nd 9 abundance on ! e>?2 & x is highly probable t petroleum has be5 d]iv$ f ! rema9s ( vegetable life4 ,_m liquids are fabricat$ by liv+ organisms1 su* z turp5t9e1 alcohol1 olive oil1 ca/or oil1 & all ! num]\s vegetable oils ) :i* we are all famili>4 ,b 9 addition to ^!1 !re are _m liquids produc$ 9 ! laboratory ( ! *emi/1 _m ( :i* are ( great importance2 = example1 nitric acid1 sulphuric acid1 & anil9e4 ,! progress ( *emical sci5ce has greatly enl>g$ ! numb] ( liquids available1 & 9 our exp]im5ts we %all frequ5tly utilize ^! products ( ! *emi/'s skill1 = !y (t5 possess prop]ties n usually associat$ ) ! common] liquids4 99,g5]al ,prop]ties ( ,liquids499--,no sci5tific /udy c be pursu$ to advantage unless ! und]ly+ pr9ciples be und]/ood2 & h5ce x w be necess>y1 9 ! beg9n+1 to ref] to c]ta9 prop]ties possess$ by all liquids1 :atev] _! orig94 ,! mo/ prom95t *>act]i/ic ( a liquid is mobility1 or fre$om ( movem5t ( its p>ts4 ,x is ow+ to ?is prop]ty t a liquid1 :5 plac$ 9 a vessel1 fl[s 9 all directions until x rea*es ! sides2 & x is ?is same fre$om ( movem5t :i* enables wat]1 ga!r+ on ! hills1 to fl[ "u ! pull ( gravitation into ! l[l&s1 & f9ally to ! sea4 ,if we drop a small quantity ( a /rongly-col\r$ fluid--su* z ink--into a l>ge volume ( wat]1 & /ir ! mixture = a %ort "t1 ! col\r is ev5ly di/ribut$ ?r\gh\t ! :ole mass ( wat]1 because ! fre$om ( movem5t ( ! p>ticles enables ! diff]5t portions to int]m+le readily4 ,?is prop]ty ( mobility di/+ui%es a liquid f a solid2 = a solid ma9ta9s its own %ape1 & its sep>ate p>ts _c be made to mix freely4 ,mobility1 h[ev]1 is n possess$ 9 equal degree by all liquids4 ,petrol1 = example1 fl[s m freely ?an wat]1 :i* 9 turn is m mobile ?an glyc]9e or treacle4 ,sometimes a sub/ance exhibits prop]ties int]m$iate betwe5 ^? ( a solid & a liquid1 z1 = in/ance1 butt] 9 hot wea!r4 ,we %all n be conc]n$1 h[ev]1 ) ^! bord]-l9e sub/ances1 b %all conf9e our att5tion to well-def9$ liquids4 ,!re is ano!r feature1 h[ev]1 common to all liquids1 :i* has a mo/ important be>+ on our subject4 ,e liquid is capable ( =m+ a b\nd>y surface ( its own2 & ?is surface has ! prop]ties ( a /ret*$1 ela/ic membrane4 ,h]e9 a liquid diff]s f a gas or vap\r1 ei!r ( :i* always completely fills ! conta9+ vessel4 ,y _c h a bottle half full ( a vap\r or gas only2 if "o-half ( t already pres5t be )drawn1 ! rema9+ half imm$iately exp&s & di/ributes itself ev5ly ?r\gh\t ! bottle1 :i* is ?us always fill$4 ,b a liquid may be p\r$ to any height 9 a vessel1 because x =ms its own b\nd>y at ! top4 ,let u n[ take a di% conta9+ ! commone/ ( all liquids1 & 9 _m ways ! mo/ rem>kable--wat]--& exam9e "s ( ! prop]ties ( ! upp] surface4 99,prop]ties ( ! ,surface ,sk9 ( ,wat]499--,"h is a flat piece ( ?9 %eet silv]1 :i*1 volume = volume1 is #aj #a_/b times z heavy z wat]1 9 :i* x might !re=e be expect$ to s9k if plac$ ^u ! surface4 ,i l[] x g5tly1 by means ( a piece ( cotton1 until x j rea*es ! top1 & !n let g ! cotton4 ,in/ead ( s9k+1 ! piece ( silv] floats on ! surface2 & moreov]1 a c]ta9 am\nt ( pressure may be appli$ to x )\t caus+ x to fall to ! bottom ( ! wat]4 ,by alt]nately apply+ & relax+ ! pressure we are able1 )9 small limits1 to make ! %eet ( silv] bob up & d[n z if x 7 a piece ( cork4 ,if we look closely1 we notice t ! wat] b5ea? ! silv] is at a l[] level ?an ! re/ ( ! surface1 ! dimple ?us =m$ be+ visible at ! edge ( ! float+ %eet 7,fig4 #a74 ,if n[ ,i apply a great] pressure1 ! piece ( silv] breaks ?r\gh ! surface & s9ks rapidly to ! bottom ( ! vessel4 ,or1 if in/ead ,i place a ?ick piece ( silv]1 su* z a %ill+1 on ! surface ( ! wat]1 we f9d t ?is w n float1 b s9ks imm$iately4 ,all ^! results are 9 agreem5t ) ! supposition t ! surface lay] ( wat] possesses ! prop]ties ( a v ?9 ela/ic %eet4 ,if we c\ld obta9 an extremely f9e %eet ( /ret*$ rubb]1 :i* w\ld m]ely =m a depression "u ! weight ( ! ?9 piece ( silv]1 b w\ld break "u ! application ( a fur!r pressure or ! weight ( a heavi] %eet1 ! condition ( ! wat] surface w\ld !n be realiz$4 ,we may note 9 pass+ t a %eet ( metal re/+ on ! surface ( wat] is a ph5om5on q di/9ct f ! float+ ( an iron %ip1 or holl[ metal vessel1 :i* s9ks until x has displac$ an am\nt ( wat] equal 9 weight to itself4 ,illu/ration3 ,fig4 #a4--,silv] %eet float+ on wat]4 ,we c n[ und]/& :y a wat]-beetle is able to run across ! surface ( a pond1 )\t wett+ its legs or runn+ any risk ( s9k+4 ,ea* ( its legs produces a dimple 9 ! surface1 b ! pressure on any "o leg is n suffici5t to break ?r\gh ! sk94 ,we c imitate ?is by br++ ! po9t ( a lead p5cil g5tly to ! surface ( wat]1 :5 a dimple is produc$1 b ! sk9 is n actually p5etrat$4 ,on remov+ ! p5cil1 ! dimple imm$iately disappe>s1 j z ! depression caus$ by pu%+ ! f+] into a /ret*$ %eet ( indi>ubb] becomes /raight imm$iately ! f+] is remov$4 99,ela/ic ,sk9 ( o!r ,liquids--,m9imum ,!rmomet]499--,! possession ( an ela/ic sk9 at ! surface is n conf9$ to wat]1 b is common to all liquids4 ,! /r5g? ( ! sk9 v>ies ) diff]5t liquids1 mo/ ( :i* are inf]ior to wat] 9 ?is respect4 ,! surface ( petroleum1 = example1 is ruptur$ by a weight :i* a wat] surface c readily su/a94 ,b :]ev] we h a free liquid surface1 we %all always f9d ?is ela/ic lay] at ! b\nd>y1 & ,i w n[ %[1 by ! aid ( lant]n projection1 an example 9 :i* ! pres5ce ( ?is lay] is utiliz$4 ,on ! scre5 is %[n ! /em ( a m9imum !rmomet]--t is1 a !rmomet] int5d$ to indicate ! l[e/ temp]ature rea*$ dur+ a giv5 p]iod4 ,! liquid us$ 9 ?is in/rum5t is alcohol1 & y w obs]ve t ! t]m9ation ( ! column is curv$ 7,fig4 #b74 ,9 contact ) ! end ( ! column is a ?9 piece ( col\r$ glass1 ) r\nd$ ends1 :i* fits loosely 9 ! /em1 & s]ves z an index4 ,:5 ,i w>m ! bulb ( ! !rmomet]1 y notice t ! end ( ! column moves =w>d1 b ! index1 r\nd :i* ! alcohol c fl[ freely1 does n *ange its position4 ,on incl9+ ! /em1 ! index slides to ! end ( ! column1 b its r\nd$ end does n p5etrate ! ela/ic sk9 at ! surface4 ,i n[ p\r cold wat] ov] ! bulb1 :i* causes ! alcohol to contract1 & consequ5tly ! end ( ! column moves t[>ds ! bulb4 ,9 do+ s1 x enc\nt]s ! opposition ( ! index1 :i* endeav\rs to p5etrate ! surface2 b we see t ! ela/ic sk91 al?\gh some:at flatt5$1 is n pi]c$1 b is /rong en\gh to pu% ! index 9 front ( x4 ,& s ! index is c>ri$ t[>ds ! bulb1 & its position indicates ! l[e/ po9t atta9$ by ! end ( ! column--t is1 ! m9imum temp]ature4 ,obvi\sly1 a !rmomet] ( ?is k9d mu/ be m\nt$ horizontally1 to prev5t ! index fall+ by its own weight4 ,illu/ration3 ,fig4 #b4--;,column & index ( m9imum !rmomet]4 99,b\nd>y ,surface ( two ,liquids499--,s f> we h be5 consid]+ surfaces b\nd$ by air1 or--9 ! case ( ! alcohol !rmomet]--by vap\r4 ,x is possible1 h[ev]1 = ! surface ( "o liquid to be b\nd$ by a second liquid1 provid$ ! two d n mix4 ,we may1 = example1 p\r petroleum on to wat]1 :5 ! top ( ! wat] w be 9 contact ) ! float+ oil4 ,if n[ we l[] our piece ( silv] foil ?r\gh ! petroleum1 & all[ x to rea* ! surface ( ! wat]1 we f9d t ! ela/ic sk9 is /ill capable ( su/a9+ ! weight2 & ?us we see t ! ela/ic lay] is pres5t at ! junction ( ! two liquids4 ,:at is true ( wat] & oil 9 ?is respect also holds good = ! b\nd>y or int]face ( any two liquids :i* d n mix4 ,evid5tly1 if ! two liquids int]m+l$1 !re w\ld be no def9ite b\nd>y betwe5 !m2 & ?is w\ld be ! case ) wat] & alcohol1 = example4 99,area ( ,/ret*$ ,surface499--,we w n at pres5t discuss ! nature ( ! =ces :i* give rise to ?is rem>kable prop]ty ( a liquid surface1 b w consid] "o ( ! effects4 ,! t5d5cy1 z 9 ! case ( all /ret*$ membranes1 w be to r$uce ! area ( ! surface to a m9imum4 ,if we take a disc ( /ret*$ indi>ubb] & place a weight ^u x1 we cause a depression :i* increases ! area ( ! surface4 ,b on remov+ ! weight1 ! disc imm$iately flatt5s out1 & ! surface is re/or$ to its orig9al smalle/ dim5sion4 ,n[1 9 practice1 ! surface ( a liquid is frequ5tly prev5t$ f atta9+ ! smalle/ possible area1 ow+ to ! contr>y action ( sup]ior =ces2 b ! t5d5cy is always manife/1 & :5 ! oppos+ =ces are abs5t or balanc$ ! surface always possesses ! m9imum size4 ,a simple exp]im5t w s]ve to illu/rate ?is po9t4 ,i dip a glass rod into treacle or gold5 syrup1 & )draw x ) a small quantity ( ! syrup adh]+ to ! end4 ,i !n hold ! rod ) ! sme>$ end d[nw>ds1 & ! syrup falls f x sl[ly 9 ! =m ( a long1 tap]$ column4 ,:5 ! column has become v ?91 h[ev]1 ow+ to ! dim9i%$ supply ( syrup f ! rod1 we notice t x breaks across1 & ! upp] portion !n %r9ks upw>ds & rema9s atta*$ to ! rod 9 ! =m ( a small drop 7,fig4 #c74 ,s long z ! column 0 ?ick1 ! t5d5cy ( ! surface lay] to r$uce its area to ! smalle/ dim5sions 0 ov]p[]$ by gravity2 b :5 ! column became ?91 & consequ5tly less 9 weight1 ! ela/ic =ce ( ! out] surface 0 /rong en\gh to ov]come gravitation1 & ! column 0 !re=e lift$1 its area ( surface gr[+ less & less z x rose1 until ! smalle/ area possible "u ! conditions 0 atta9$4 ,illu/ration3 ,fig4 #c4--,?read ( gold5 syrup ris+ & =m+ a drop4 99,%ape ( ,deta*$ ,masses ( ,liquid499--,let u n[ pay a little att5tion to ! small drop ( syrup :i* rema9s hang+ f ! rod4 ,x is 9 contact ) ! glass at ! top "p only1 & ! l[] portion is only prev5t$ f fall+ by ! ela/ic sk9 ar\nd x1 :i* su/a9s ! weight4 ,we may comp>e x to a bladd] full ( liquid1 9 :i* case also ! weight is borne by ! conta9+ sk94 ,n[ suppose we c\ld sep>ate ! drop ( syrup entirely f ! rod2 :at %ape w\ld x take8 ,we "k t its surface1 if n prev5t$ by outside =ces f do+ s1 w\ld become ( m9imum area4 ,assum+ su* extrane\s =ces to be abs5t or c\nt]balanc$1 :at w\ld !n be ! %ape ( ! drop8 ,x w\ld be an exact sph]e4 ,= a sph]e has a less surface-area 9 proportion to its volume ?an any o!r %ape2 & h5ce a free drop ( liquid1 if its outl9e 7 det]m9$ solely by its ela/ic sk91 w\ld be sph]ical4 ,a num]ical example w s]ve to illu/rate ?is prop]ty ( a sph]e4 ,suppos+ we con/ruct ?ree clos$ vessels1 ea* to conta9 #a cubic foot1 ! fir/ be+ a cube1 ! second a cyl9d] ( l5g? equal to its diamet]1 & ! ?ird a sph]e4 ,! areas ( ! surfaces w\ld !n be3-- ,cube 4 4 4 4 #f squ>e feet4 ,cyl9d] 4 4 4 4 #e4hf 11 11 ,sph]e 4 4 4 4 #d4i 11 11 ---------------------------------------- -------------- ,& :atev] %ape we make ! vessel1 x w always be f\nd t ! sph]ical =m possesses ! lea/ surface4 ,illu/ration3 ,fig4 #d4--;,drops ( diff]5t sizes re/+ on flat plate4 ,n[ let u exam9e "s ( ! %apes :i* drops actually assume4 ,i take a glass plate cov]$ ) a ?9 lay] ( grease1 :i* prev5ts adhesion ( wat] to ! glass1 & =m ^u x drops ( wat] ( v>i\s sizes by ! aid ( a pipette4 ,y see !m project$ on ! scre5 7,fig4 #d74 ,! l>g] drops are flatt5$ above & bel[1 b possess r\nd$ sides & resemble a teacake 9 %ape4 ,^? ( int]m$iate size are m globul>1 b /ill %[ signs ( flatt5+2 :il/ ! v small ones1 s f> z ! eye c judge1 are sph]ical4 ,evid5tly1 ! %ape dep5ds ^u ! size2 & ?is calls = "s explanation4 ,if we take a balloon ( indi>ubb] fill$ ) wat]1 & re/ x on a table1 ! weight ( ! enclos$ wat] w naturally t5d to /ret* ! balloon sideways1 & s to flatt5 x4 ,a small] balloon1 made ( rubb] ( ! same /r5g?1 w n be /ret*$ s mu*1 z ! weight ( ! enclos$ wat] w\ld be less2 & if ! balloon 7 v small1 b /ill _h walls ( ! same /r5g?1 ! weight ( ! enclos$ wat] w\ld be incompet5t to produce any visible di/ortion4 ,x is evid5t1 h[ev]1 t s long z x is "u ! influ5ce ( gravitation1 ev5 ! smalle/ drop _c be truly sph]ical1 b w be slightly flatt5$4 ,! t5d5cy ( drops to become sph]ical1 h[ev]1 is always pres5t4 ,illu/ration3 ,fig4 #e4--;,=mation ( a sph]e ( or?otoluid9e4 99,production ( ,true ,sph]es ( ,liquids499--,n[ x is q possible to produce true sph]es ( liquid1 ev5 ( l>ge size1 if we cancel ! effect ( gravity2 & we may obta9 a h9t z to h[ ?is may be accompli%$ by consid]+ ! case ( a soap-bubble1 :i*1 :5 float+ 9 air1 is sph]ical 9 %ape4 ,su* a bubble is m]ely a sk9 ( liquid enclos+ air2 b be+ surr\nd$ by air ( ! same d5sity1 !re is no t5d5cy = ! bubble to di/ort1 nor w\ld x fall to ! gr\nd 7 x n = ! weight ( ! extremely ?9 sk94 ,! d[nw>d pull ( gravity on ! air inside ! bubble is balanc$ by ! buoyancy ( ! outside air2 & h5ce ! sk91 unhamp]$ by any extrane\s =ce1 assumes & reta9s ! sph]ical =m4 ,& simil>ly1 if we c arrange to surr\nd a drop ( liquid by a m$ium ( ! same d5sity1 x w 9 turn become a sph]e4 ,evid5tly ! m$ium us$ mu/ n mix ) ! liquid compos+ ! drop1 z x w\ld !n be impossible to e/abli% a b\nd>y surface betwe5 ! two4 ,plateau1 _m ye>s ago1 produc$ liquid sph]es 9 ?is mann]4 ,he prep>$ a mixture ( alcohol & wat] exactly equal 9 d5sity to olive oil1 & dis*>g$ ! oil into ! mixture1 ! buoyancy ( :i* exactly c\nt]act$ ! effect ( gravity on ! oil1 & h5ce sph]es 7 =m$4 ,! prep>ation ( an alcohol-wat] mixture ( exactly correct d5sity is a t$i\s process1 & we are n[ able to disp5se ) x & =m true sph]es 9 a m conv5i5t way4 ,!re is a liquid kn[n z or?otoluid9e1 :i* possesses a beautiful r$ col\r1 does n mix ) wat]1 & :i* has exactly ! same d5sity z wat] :5 ! temp]ature ( bo? is #ge deg4 ,f4 or #bd deg4 ,c4 ,at ?is temp]ature1 !re=e1 if or?otoluid9e be run into wat]1 sph]es %\ld be =m$2 & !re is no reason :y we %\ld n be able to make "o z l>ge z a cricket-ball1 or ev5 l>g]4 ,i take a flat-sid$ vessel = ?is exp]im5t1 9 ord] t ! appe>ance ( ! drop w n be di/ort$ z x w\ld be 9 a beak]1 & p\r into x wat] at #ge deg4 ,f4 until x is ab\t two-?irds full4 ,i n[ take a pipette conta9+ a #c p] c5t4 solution ( common salt1 & dis*>ge x at ! bottom ( ! wat]4 ,be+ heavi]1 ! salt solution w rema9 bel[ ! wat]1 & w s]ve z a re/+-place = ! drop4 ,! or?otoluid9e is conta9$ 9 a vessel provid$ ) a tap & wide /em1 :i* is n[ ins]t$ 9 ! wat] s t ! end ( ! /em is ab\t #a in* above ! top ( ! salty lay]4 ,i n[ op5 ! tap s z to all[ ! or?otoluid9e to fl[ out gradually2 & we !n see ! ball ( liquid gr[+ at ! end ( ! /em 7,fig4 #e74 ,by us+ a graduat$ vessel1 we c read (f ! quantity ( or?otoluid9e :i* runs out1 & ?us measure ! volume ( ! sph]e =m$4 ,:5 ! l[] "p rea*es ! lay] ( salt solution1 we raise ! deliv]y tube g5tly1 & repeat ?is z ne$$ dur+ ! gr[? ( ! sph]e4 ,we h n[ run out #ajj cubic c5timetres1 or ab\t "o-six? ( a p9t1 & our sph]e consequ5tly has a diamet] ( #e #c_/d c5timetres1 or #b #a_/d in*es4 ,to set x free 9 ! wat] we lift ! deliv]y tube rapidly--& !re is ! sph]e float+ 9 ! wat] 7,fig4 #f74 ,we c\ld h made x z mu* l>g] z we pleas$1 b ! pres5t sph]e w s]ve all our requirem5ts4 ,illu/ration3 ,fig4 #f4--,! deta*$ sph]e float+ "u wat]4 ,illu/ration3 ,fig4 #g4--,! ,c5trifugoscope4 99,! ,c5trifugoscope499--,i h "h a toy1 :i* we may suitably call ! c5trifugoscope1 :i* %[s 9 a simple way ! =mation ( sph]es ( liquid 9 a m$ium ( practically equal d5sity4 ,x consi/s ( a l>ge glass bulb atta*$ to a /em1 ab\t ?ree-qu>t]s full ( wat]1 ! rema9+ qu>t] be+ occupi$ by or?otoluid9e4 ,?is liquid1 be+ slightly d5s] ?an wat] at ! temp]ature ( ! room1 re/s on ! bottom ( ! bulb4 ,:5 ,i hold ! /em horizontally1 & rotate x--sudd5ly at fir/1 & /eadily aft]w>ds--a numb] ( fragm5ts are deta*$ f ! or?otoluid9e1 :i* imm$iately become sph]ical1 & rotate ne> ! out] side ( ! bulb4 ,! ma9 mass ( ! r$ liquid rises to ! c5tre ( ! bulb1 & rotates on its axis 7,fig4 #g71 & we ?us get an imitation ( ! sol> sy/em1 ) ! planets ( v>i\s sizes revolv+ r\nd ! c5tral mass2 & ev5 ! a/]oids are repres5t$ by ! num]\s t9y sph]es :i* are always torn (f f ! ma9 body ( liquid along ) ! l>g] ones4 ,:5 ! rotation ceases1 ! deta*$ sph]es s9k1 & aft] a %ort "t jo9 ! p>5t mass ( or?otoluid9e4 ,we c !re=e take ?is simple app>atus at any "t1 & use x to %[ t a mass ( liquid1 possess+ a free surface all r\nd1 & unaffect$ by gravity1 automatically becomes a sph]e4 ,aft] all1 ?is is only :at we %\ld expect ( an ela/ic sk9 fill$ ) a free-fl[+ m$ium4 99,effect ( ,temp]ature on ,sph]e ( ,or?otoluid9e499--,i w n[ return to ! l>ge sph]e =m$ "u wat] 9 ! flat-sid$ vessel1 & direct y\r att5tion to an exp]im5t :i* tea*es an important lesson4 ,by plac+ a little ice on ! top ( ! wat]1 we are enabl$ to cool ! cont5ts ( ! vessel1 & we soon notice t ! r$-col\r$ sph]e becomes flatt5$ on ! top & bel[1 & s9ks a %ort di/ance into ! sal9e lay]4 ,evid5tly ! cool+ action1 :i* has affect$ bo? liquids1 has caus$ ! or?otoluid9e to become d5s] ?an wat]4 ,i n[ surr\nd ! vessel ) w>m wat]1 & all[ ! cont5ts gradually to atta9 a temp]ature high] ?an #ge deg4 ,f4 ,y obs]ve t ! flatt5$ drop *anges 9 %ape until x is aga9 sph]ical2 & z ! heat+ is cont9u$ elongates 9 a v]tical direction1 & !n rises to ! surface1 be+ n[ less d5se ?an wat]4 ,s s5sitive are ^! temp]ature effects t a diff]5ce ( #a degree on ei!r side ( #ge deg4 ,f4 causes a p]ceptible dep>ture f ! sph]ical %ape 9 ! case ( a l>ge drop4 ,x !re=e foll[s t or?otoluid9e may be ei!r heavi] or light] ?an wat]1 accord+ to temp]ature1 & ?is fact admits ( a simple explanation4 ,or?otoluid9e exp&s m ?an wat] on heat+1 & contracts m on cool+4 ,! effect ( expansion is to decrease ! d5sity1 & ( contraction to increase x2 h5ce ! reason :y w>m air rises ?r\gh cold air1 & vice v]sa4 ,n[ if or?otoluid9e & wat]1 :i* are equal 9 d5sity at #ge deg4 ,f41 exp&$ or contract$ equally on heat+ above or cool+ bel[ ?is temp]ature1 _! d5sities w\ld always be id5tical4 ,b inasmu* z or?otoluid9e increases 9 volume to a great] ext5t ?an wat] on heat+1 & %r9ks m on cool+1 x becomes light] ?an wat] :5 bo? are hott] ?an #ge deg4 ,f41 & heavi] :5 bo? are cold]4 ,we call ! temp]ature :5 bo? are equal 9 d5sity ! equi-d5sity temp]ature4 ,"h are "s figures :i* %[ h[ ! d5sities ( ^! two liquids div]ge f a common value on heat+ or cool+1 & :i* e/abli% ! conclusions we h drawn3-- ---------------------------------------- --------------------------- ,temp]ature4 ,d5sity4 ,deg4 ,f4 ,deg4 ,c4 ,wat]4 ,or?otoluid9e4 ---------------------------------------- --------------------------- #ej #aj #j4iiig #a4jji #ei #ae #j4iiia #a4jje #fh #bj #j4iihb #a4jja ,equal3 #ge #bd #j4iigc #j4iig #hf #cj #j4iieg #j4iib #ie #ce #j4iidj #j4ihh #ajd #dj #j4iibc #j4ihc ---------------------------------------- --------------------------- ,illu/ration3 ,fig4 #h4--;,anil9e drops fall+ ?r\gh cold wat] & asc5d+ ?r\gh hot wat]4 99,o!r ,examples ( ,equi-,d5sity499--,!re are _m o!r liquids :i*1 l or?otoluid9e1 may be heavi] or light] ?an wat]1 accord+ to temp]ature1 & ,i n[ wi% to br+ to y\r notice ! rem>kable liquid anil9e1 :i* falls "u ?is head4 ,anil9e is an oily liquid1 :i*1 unless specially purifi$1 has a deep r$ col\r4 ,x =ms ! basis ( ! beautiful & v>i$ col\r+ mat]ials kn[n z ! anil9e dyes1 :i* we owe to ! skill ( ! *emi/4 ,! equi-d5sity temp]ature ( wat] & anil9e is #adg deg4 ,f4 or #fd deg4 ,c42 t is1 anil9e w s9k 9 wat] if bo? be cold] ?an #adg deg4 ,f41 & rise to ! surface if ?is temp]ature be exce$$4 ,we may illu/rate ?is fact by a simple b /rik+ exp]im5t4 ,"h are two tall beak]s side by side1 & above !m a ci/]n conta9+ anil9e 7,fig4 #h74 ,! /em ( ! ci/]n communicates ) ! two bran*es ( a horizontal tube1 ! t]m9ation ( "o bran* be+ ne> ! top ( "o ( ! beak]s1 :il/ ! o!r bran* is prolong$ to ! bottom ( ! second beak]1 & is curv$ upw>ds at ! end4 ,bo? bran*es are provid$ ) taps to regulate ! fl[ ( liquid1 & to comm5ce ) are full ( anil9e4 ,cold wat] is p\r$ into ! beak] conta9+ ! %ort] bran* until ! end is subm]g$2 & wat] ne>ly boil+ is plac$ 9 ! second beak] to an equal height4 ,i n[ op5 ! taps1 s t ! anil9e may fl[ gradually into ea* beak]2 & y notice t ! drops ( anil9e s9k ?r\gh ! cold wat] & rise ?r\gh ! hot4 ,we h ?us ! same liquid desc5d+ & asc5d+ simultane\sly 9 wat]1 ! only diff]5ce be+ t ! wat] is cold on ! "o side & hot on ! o!r4 ,prolong+ ! deliv]y-tube to ! bottom ( ! beak] conta9+ ! hot wat] enables ! ris+ drops to be obs]v$ ?r\gh\t ! l5g? ( ! column ( wat]2 & 9 addition enables ! cold anil9e f ! ci/]n to be w>m$ up on its way to ! outlet1 s t by ! "t x escapes its temp]ature is practically ! same z t ( ! wat]4 ,if ?is temp]ature exce$ #adg deg4 ,f41 ! drops w rise4 ,we might1 9 ?is exp]im5t1 h us$ or?otoluid9e in/ead ( anil9e2 or1 inde$1 any o!r liquid equal 9 d5sity to wat] at "s temp]ature int]m$iate betwe5 ^? ( ! hot & cold wat]--always provid$ t ! liquid *os5 did n mix ) wat]4 ,among/ su* o!r liquids may be m5tion$ anisol2 butyl b5zoate2 & aceto-acctic e!r2 b none ( ^! possess ! f9e col\r ( anil9e or its *emical relative or?otoluid9e1 & 9 addition are m co/ly liquids4 ,besides ^! are a numb] ( o!r liquids r>] /ill1 practically only kn[n to ! *emi/1 :i* behave 9 ! same way4 ,^! liquids are all c>bon comp\nds1 & m or less oily 9 "*4 ,!re is a simple rule :i* may be us$ to pr$ict :e!r any organic liquid w be bo? light] & heavi] ?an wat]1 accord+ to temp]ature4 ,"h x is3 ,if ! d5sity ( ! liquid at #cb deg4 ,f4 or #j deg4 ,c4 be n great] ?an #a4ab1 ! liquid w become less d5se ?an wat] bel[ #bab deg4 ,f4 or #ajj deg4 ,c41 at :i* temp]ature wat] boils4 ,?is rule is d]iv$ f a k ( ! ext5t to :i* ! expansion ( organic liquids 9 g5]al exce$s t ( wat]4 ,i h consid]$ x necess>y to ent] at "s l5g? into ?is subject ( equi-d5sity1 z mu* t w foll[ involves a k ( ?is physical relation betwe5 liquids4 99,anil9e ,films or ,sk9s499--,we h previ\sly conclud$1 l>gely f circum/antial evid5ce1 t a liquid drop is encas$ 9 a sk9 or :at is equival5t to a sk91 & ,i propose n[ to %[ by exp]im5ts ) anil9e h[ we c con/ruct a drop1 comm5c+ ) a sk9 ( liquid4 ,"h is "s anil9e 9 a vessel1 cov]$ by wat]4 ,i l[] into ! anil9e a circul> frame ( wire1 :i* ,i !n raise sl[ly into ! ov]ly+ wat]2 & y obs]ve t a film ( anil9e rema9s /ret*$ across ! frame4 ,by lift+ ! frame up & d[n 9 ! wat] ! sk9 is /ret*$1 =m+ a drop :i* is con/rict$ ne> ! frame 7,fig4 #i74 ,on lift+ ! wire m sudd5ly1 ! sk9 ( anil9e closes 9 completely at ! n>r[ "p1 & a sph]e ( wat]1 encas$ 9 an anil9e sk91 !n falls ?r\gh ! wat] 9 ! beak]1 & comes to re/ on ! anil9e bel[--into :i*1 h[ev]1 x soon m]ges4 ,y 7 previ\sly ask$ to reg>d a drop ( liquid z be+ simil> to a fill$ soap-bubble2 & ?is exp]im5t realizes ! t]ms ( ! def9ition4 ,& x requires only a little imag9ation to picture a drop surr\nd$ by its own sk9 in/ead ( t ( ano!r liquid4 ,x is easy to make "o ( ^! enclos$ wat]-drops by imitat+ ! bl[+ ( a soap-bubble--us+1 h[ev]1 wat] in/ead ( air4 ,9 ord] to d ?is ,i take a piece ( glass tub+1 op5 at bo? ends1 & pass x d[n ! vessel1 until x rea*es ! anil9e4 ,wat]1 9 ! meantime1 has ent]$ ! tube1 to ! same height z t at :i* x /&s 9 ! vessel4 ,on rais+ ! tube g5tly1 a sk9 ( anil9e adh]es to ! end2 & z we raise x /ill fur!r1 ! wat] 9 ! tube1 s9k+ s z to rema9 at ! level 9 ! vessel1 exp&s ! sk9 into a sph]e 7,fig4 #i7--! equival5t ( a fill$ soap-bubble4 ,on )draw+ ! tube gradually1 ! composite sph]e is left hang+ f ! surface ( ! wat]4 ,illu/ration3 ,fig4 #i4--;,anil9e sk9s envelop+ wat]4 99,surface ,t5sion499--,be=e proce$+ fur!r1 x w be advisable to introduce & expla9 ! t]m surface t5sion4 ,we frequ5tly use x1 )\t atta*+ to x any num]ical value1 to express ! fact t ! free surface ( a liquid is subject$ to /ret*+ =ces1 or is 9 a /ate ( t5sion2 & ?us we say t c]ta9 ph5om5a are due to surface t5sion4 ,b ! physici/ does n cont5t himself ) m]ely obs]v+ occurr5ces2 he tries also to measure1 9 def9ite units1 ! quantities involv$ 9 ! ph5om5a4 ,& h5ce surface t5sion is def9$ z ! =ce t5d+ to pull ap>t ! two portions ( ! surface on ei!r side ( a l9e #a c5timetre 9 l5g?4 ,t is1 we imag9e a l9e #a c5timetre long on ! surface ( ! liquid1 divid+ ! surface into two portions on opposite sides ( ! l9e1 & we call ! =ce t5d+ to pull ^! two portions away f ea* o!r ! surface t5sion4 ,exp]im5ts %[ t ?is =ce1 9 ! case ( cold wat]1 is equal to ab\t #ge dynes1 or ne>ly #h_/ajj ( a gramme4 ,if we *oose a l9e #a in* long on ! surface ( wat]1 ! surface t5sion is repres5t$ by ab\t #c #a_/f gra9s4 ,x is always necess>y to specify ! l5g? :5 assign+ a value to ! surface t5sion2 & unless o!rwise /at$ a l5g? ( #a c5timetre is impli$4 ,! values = diff]5t liquids v>y consid]ably2 & x is also necess>y to note t ! figure = a giv5 liquid dep5ds ^u ! nature ( ! m$ium by :i* x is b\nd$--:e!r1 = example1 ! surface is 9 contact ) air or ano!r liquid4 ,! foll[+ table gives ! values = sev]al liquids :5 ! surfaces are 9 contact ) air3-- ---------------------------------------- -------------------------- ,liquid4 ,t5sion at #ae deg4 ,c4 7#ei deg4 ,f471 dynes p] cm4 ---------------------------------------- -------------------------- ,wat] #ge ,anil9e #dc ,olive ,oil #cb ,*lor(orm #bg ,alcohol #be ---------------------------------------- -------------------------- ,:5 "o liquid is b\nd$ by ano!r1 ! int]facial t5sion1 z x is call$1 is g5]ally less ?an :5 9 contact ) air4 ,?us ! value = wat] & olive oil is ab\t #ba dynes p] c5timetre at #ae deg4 ,c4 ,we are n[ 9 a position to speak ( surface t5sion quantitatively1 & %all frequ5tly f9d x necess>y to d s 9 ord] to expla9 matt]s :i* w come "u our notice lat]4 ,illu/ration3 ,figs4 #aj1 #aa & #ab4--,! ,div+ ,drop4 ,?ree /ages4 99,! ,div+ ,drop499--,9 ord] to illu/rate ! t5sion at ! b\nd>y surface ( two liquids1 ,i n[ %[ an exp]im5t 9 :i* a drop is =cibly project$ d[nw>ds by ! op]ation ( ?is t5sion4 ,i p\r "s wat] into a n>r[ glass vessel1 & float ^u x a liquid call$ dime?yl-anil9e1 s z to =m a lay] ab\t #a in* 9 dep?4 ,a glass tube1 op5 at bo? ends1 is n[ pass$ d[n ! float+ liquid into ! wat]1 & !n rais$ gradually1 ) ! result t a sk9 ( wat] adh]es to ! end1 & is inflat$ by ! upp] liquid1 =m+ a sph]e on ! end ( ! tube 7,fig4 #aj74 ,on )draw+ ! tube f ! upp] surface1 ! sph]e is deta*$ & falls to ! b\nd>y surface1 :]e x re/s = a few seconds1 & is !n sudd5ly %ot d[nw>ds into ! wat] 7,figs4 #aa & #ab74 ,x !n rises to ! int]face2 breaks ?r\gh1 & m+les ) ! float+ liquid1 !reby los+ its id5tity4 ,:y %\ld ! drop1 :i* is less d5se ?an wat]1 dive bel[ 9 ?is mann]8 ,! explanation is t ! drop 7:i* consi/s ( a sk9 ( wat] fill$ ) dime?yl-anil9e71 aft] re/+ = a "t on ! jo9+ surface1 loses ! "u "p ( its sk91 :i* m]ges into ! wat] bel[4 ,! %ape ( ! b\nd>y ( ! two liquids is !reby alt]$1 ! sides n[ be+ cont9u\s ) ! sk9 =m+ ! upp] "p ( ! drop4 ,?is is an un/able %ape2 & accord+ly ! b\nd>y surface flatt5s to its normal condition1 & ) su* =ce z to cause ! drop b5ea? x to dive into ! wat]1 al?\gh ! liquid is light] ?an wat] & t5ds to float4 ,! result is ! same z t :i* w\ld occur if a m>ble 7 press$ on to a /ret*$ disc ( rubb]1 & !n releas$1 :5 x w\ld be project$ upw>ds ow+ to ! /raight5+ ( ! disc4 ,i n[ repeat ! exp]im5t1 us+ p>aff9 oil in/ead ( dime?yl-anil9e2 b 9 ?is case ! drop is only project$ to a small dep?1 & ! effect is n s m>k$4 ,! exp]im5t furni%es conclusive evid5ce ( ! exi/5ce ( ! int]facial t5sion4 99,=mation ( ,fall+ ,drops ( ,liquid499--,we w n[ direct our att5tion to "o ( ! mo/ beautiful ( natural ph5om5a--! gr[? & p>tition ( a drop ( liquid4 ,let u obs]ve1 by ! aid ( ! lant]n1 ?is process 9 ! case ( wat]1 fall+ 9 drops f ! end ( a glass tube4 ,! fl[ ( wat] is controll$ by a tap1 & y obs]ve t ! drop on ! end gradually gr[s 9 size1 !n becomes n>r[] ne> ! end ( ! tube1 & breaks across at ?is n>r[ "p1 ! sep>at$ drop fall+ to ! gr\nd4 ,ano!r drop !n gr[s & breaks away2 b ! process is s rapid t ! details _c be obs]v$4 ,none ( y saw1 = example1 t ea* l>ge drop aft] sev]ance 0 foll[$ by a small droplet1 =m$ f ! n>r[$ portion f :i* ! ma9 drop p>t$4 ,b ! small1 second>y drop is always pres5t1 & is call$1 9 hon\r ( its discov]]1 ,plateau's sph]ule4 ,nor did any ( y obs]ve t ! l>ge drop1 imm$iately aft] sep>ation1 became flatt5$ at ! top1 nor 7 y able to notice ! *ang+ %ape ( ! n>r[ portion4 ,to %[ all ^! ?+s x w be necess>y to modify ! exp]im5tal conditions4 ,mr4 ,h4 ,g4 ,wells1 9 "o ( 8 %ort /ories1 describes ! wond]ful effects ( a dose ( a peculi>ly pot5t drug1 call$ by him ! ,accel]ator4 ,:ile its influ5ce la/$1 all ! p]ceptions 7 spe$$ up to a rem>kable degree1 s t occurr5ces :i* normally appe>$ to be rapid seem$ absurdly sl[4 ,a cycli/1 = example1 al?\gh travell+ at 8 be/ pace1 sc>cely appe>$ to be mak+ any movem5t2 & a fall+ body look$ z if x 7 /ation>y4 ,n[ if we c\ld come into possession ( "s ( ?is m>vell\s comp\nd1 & take ! prescrib$ quantity1 we %\ld !n be able to exam9e all t happ5s :5 a drop =ms & falls at our leisure4 ,b x is n necess>y to resort to su* means z ?is to r5d] ! process visible to ! eye4 ,we c\ld1 = example1 take a numb] ( photographs succe$+ ea* o!r by v m9ute int]vals ( "t--a k9d ( mov+ picture--f :i* ! details might be glean$ by exam9+ ! individual photographs4 ,?is proc$ure1 h[ev]1 w\ld be tr\blesome2 & evid5tly ! simple/ plan1 if x c\ld be accompli%$1 w\ld be to draw out ! "t tak5 by a drop 9 =m+ & fall+4 ,& our previ\s exp]im5ts indicate h[ ?is may be done1 z we %all see :5 we h consid]$ ! =ces at "w on ! escap+ liquid4 ,a liquid issu+ f a tube is pull$ d[nw>ds by ! =ce ( gravitation1 & !re=e is always t5d+ to fall4 ,at fir/1 :5 ! drop is small1 ! action ( gravity is ov]come by ! surface t5sion ( ! liquid2 b z ! drop gr[s 9 size & increases 9 weight1 a po9t arrives at :i* ! surface t5sion is ov]p[]$4 ,!n comm5ces ! =mation ( a neck1 :i* gr[s n>r[] "u ! /ret*+ =ce ex]t$ by ! weight ( ! drop1 until rupture takes place4 ,n[ if we wi% to make ! process m gradual1 x w be necess>y to r$uce ! effect ( gravity1 z we _c increase ! surface t5sion4 ,we h already se5 h[ ?is may be done 9 connexion ) liquid sph]es--inde$1 we 7 able to cancel ! influ5ce ( gravity entirely1 by surr\nd+ ! work+ liquid by a second liquid ( exactly equal d5sity4 ,we require n[1 h[ev]1 to all[ ! d[nw>d pull ( ! drop ultimately to ov]come ! surface t5sion1 & we mu/ !re=e =m ! drop 9 a less d5se liquid4 ,if ?is surr\nd+ liquid be only slightly less d5se1 we %\ld be able to produce a v l>ge drop2 & if we make its gr[? sl[ we may obs]ve ! :ole process ( =mation & sep>ation ) ! unaid$ eye4 ,illu/ration3 ,fig4 #ac4--;,app>atus = =m+ asc5d+ or desc5d+ drops ( liquids4 ,n[ x s happ5s t we h to h& two liquids :i*1 )\t any prep>ation1 fulfil our requirem5ts4 ,or?otoluid9e1 at temp]atures bel[ #ge deg4 ,f4 or #bd deg4 ,c41 is d5s] ?an wat] ( equal temp]ature4 ,at #ge deg4 ,f4 _! d5sities are id5tical2 & z ! ord9>y temp]ature ( a room lies betwe5 #fj deg4 & #gj deg4 ,f41 wat]1 "u ! prevail+ conditions1 w be slightly ! less d5se ( ! two1 & w !re=e =m a suitable m$ium 9 :i* to =m a l>ge drop ( or?otoluid9e4 ,i !re=e run ?is r$-col\r$ liquid into wat] f a funnel controll$ by a tap 7,fig4 #ac71 & 9 ord] to make a l>ge drop ! end ( ! /em is wid5$ to a diamet] ( #a #a_/b in*es4 ,x is be/1 :5 />t+1 to place ! end ( ! /em 9 contact ) ! surface ( ! wat]1 z ! fir/ quantity ( or?otoluid9e :i* runs d[n !n spreads ov] ! surface & atta*es itself to ! rim ( ! wid5$ end ( ! /em4 ,! tap is regulat$ s t ! liquid fl[s out sl[ly1 & we may n[ wat* ! =mation ( ! drop4 ,at fir/ x is ne>ly hemisph]ical 9 %ape2 gradually1 z y see1 x becomes m elongat$2 n[ ! "p ne> ! top comm5ces to n>r[1 =m+ a neck1 :i*1 "u ! gr[+ weight ( ! l[] portion1 is /ret*$ until x breaks1 sett+ ! l>ge drop free 7,figs4 #ad to #ah74 ,& !n foll[s ! droplet2 v small by comp>ison ) ! big drop1 b pla9ly visible 7,figs4 #ai & #bj74 ,! graceful outl9e ( ! drop at all /ages ( ! =mation mu/ appeal to all :o possess an eye = beauty 9 =m2 free-fl[+ curves t no arti/ c\ld surpass1 *ang+ cont9u\sly until ! process is complete4 ,sl[ z 0 ! =mation ( ?is drop1 x 0 /ill too rapid to enable y to trace ! orig9 ( ! droplet4 ,x came1 z x always does come1 f ! drawn-out neck4 ,:5 ! l>ge drop is sev]$1 ! mass ( liquid cl++ to ! deliv]y-tube %r9ks upw>ds1 z ! d[nw>d pull ^u x is n[ reliev$4 ,! result ( ?is %r9kage--:i*1 z usual1 r$uces ! area ( surface to ! m9imum possible--is to cut (f ! elongat$ neck1 at its upp] "p1 ?us leav+ free a sp9dle-%ap$ column ( liquid4 ,?is column imm$iately contracts1 ow+ to its surface t5sion1 until its surface is a m9imum--t is1 x becomes practically a sph]e2 & ?is con/itutes ! droplet4 ,9 a lat] exp]im5t1 9 :i* ! =mation is sl[] /ill1 & ! liquid m visc\s1 ! orig9 ( ! droplet w be pla9ly se51 & ! correctness ( ! description v]ifi$4 ,! recoil due to ! lib]ation ( ! /ret*+ =ce aft] rupture ( ! neck 0 visible on ! top ( ! l>ge drop1 & also on ! bottom ( ! portion ( liquid :i* rema9$ atta*$ to ! tube1 bo? ( :i* 7 mom5t>ily flatt5$ 7,figs4 #ai & #bj7 be=e assum+ _! f9al r\nd$ %ape4 ,?is is exactly :at we %\ld expect to happ5 if a fill$ sk9 ( indi>ubb] 7 /ret*$ until x gave way at ! n>r[e/ "p4 ,illu/ration3 ,fig4 #ad4 ,z a v>iation on ! two liquids j us$1 ,i n[ take ! yell[ liquid nitrob5z5e1 & run x into nitric acid 7or o!r suitable m$ium7 ( specific gravity #a4b1 & y obs]ve ! same sequ5ce ( ev5ts z 9 ! previ\s exp]im5t1 ev5 to ! details4 ,v rapid photography %[s t ! break+ away ( a drop ( wat] f ! end ( a tube 9 air is 9 all respects id5tical ) :at we h j se5 on a l>ge scale4 ,illu/ration3 ,figs4 #ad to #bj4--;,=mation ( a drop ( or?otoluid9e1 %[+ ! droplet4 ,sev5 /ages4 99,asc5d+ or ,inv]t$ ,drops499--,if we dis*>ge or?otoluid9e into wat] :5 bo? are hott] ?an #ge deg4 ,f41 ! =m] liquid w rise1 z its d5sity is n[ less ?an t ( wat]4 ,if1 !re=e1 ,i take a funnel ) ! /em b5t into a p>allel bran*1 s z to dis*>ge upw>ds 7,a1 ,fig4 #ac7 & raise ! temp]ature ( bo? liquids above #ge deg4 ,f41 we see t ! drop gradually gr[s t[>ds ! top ( ! wat]1 f9ally break+ away & giv+ rise to ! droplet4 ,ev]y?+1 9 fact1 0 ! same z 9 ! case ( a fall+ drop1 except t ! direction 0 rev]s$4 ,a slight rise 9 temp]ature has ?us turn$ ! :ole process topsy-turvy1 b ! action is really ! same 9 bo? cases4 ,:51 on heat+1 ! wat] acquir$ ! great] d5sity1 its buoyancy ov]came ! pull ( gravitation on ! or?otoluid9e1 & accord+ly ! drop 0 pu%$ upw>ds1 ! result be+ ! same z :5 x 0 pull$ d[nw>ds4 ,an inv]t$ drop may always be obta9$ by dis*>g+ a light liquid into a heavi] "o1 e4g4 olive oil into wat]1 or wat] into any ( ! liquids m5tion$ on p4 #ai1 bel[ ! equi-d5sity temp]ature4 ,,lecture ,,ii 99,automatic ,anil9e ,drops499--,9 ! =ego+ exp]im5ts ! drop 0 enl>g$ until x broke away by fe$+ x ) liquid2 b x is possible to arrange t ! =mation %all be q automatic4 ,! exp]im5t1 z we %all see1 is extremely simple1 & yet x conta9s an elem5t ( surprise4 ,into a beak] conta9+ wat] ne>ly boil+ ,i p\r a consid]able quantity ( anil9e1 :i* at fir/ breaks up into a l>ge numb] ( drops4 ,aft] a %ort "t1 h[ev]1 all ! anil9e floats to ! surface1 hav+ be5 w>m$ by contact ) ! wat] to a temp]ature high] ?an t ( equi-d5sity 7#adg deg4 ,f41 or #fd deg4 ,c47--:i* is exactly :at we %\ld expect to happ54 ,!re x rema9s = a brief p]iod 9 ! =m ( a l>ge mass ) ! l[] portion curv$ 9 outl9e4 ,soon1 h[ev]1 we obs]ve ! c5tre ( ! mass s9k+ 9 ! wat]1 & tak+ on ! n[ famili> outl9e ( a fall+ drop4 ,gradually1 x n>r[s at ! neck & breaks away2 b z anil9e is a visc\s liquid1 ! neck 9 ?is case is long & !re=e easily se54 ,! l>ge drop breaks away & falls to ! bottom ( ! beak]1 its upp] surface ris+ & fall+ = "s "t ow+ to ! recoil ( its sk9 aft] sep>ation1 f9ally becom+ p]man5tly convex4 ,imm$iately aft] ! l>ge drop has p>t$1 ! upp] mass %r9ks upw>ds1 spread+ out fur!r on ! surface ( ! wat]1 ) ! result t ! long neck is sev]$ at ! top1 its own weight assi/+ ! breakage4 ,n[ foll[s ! resolution ( ! deta*$ neck into two or m sph]es1 usually a l>ge & a small 7,fig4 #bb74 ,& n[1 to ^? :o view ! exp]im5t = ! fir/ "t1 comes ! surprise4 ,! l>ge drop1 :i* 0 m or less flatt5$ :5 x came to re/ at ! bottom ( ! beak]1 becomes m & m r\nd$1 & f9ally sph]ical4 ,!n1 unaid$1 x rises to ! top & m+les itself ) ! anil9e :i* rema9$ on ! surface4 ,aft] a brief int]val a second drop falls1 imitat+ ! p]=mance ( ! fir/ "o2 &1 l its pr$ecessor1 rises to ! surface1 aft] rema9+ = a %ort "t at ! bottom ( ! vessel4 ,& s long z we keep ! temp]ature a few degrees above t ( equi-d5sity1 ! process ( p>tition & reunion goes on indef9itely4 ,! action is automatic & cont9u\s1 & ! l>ge size ( ! drop & ( ! neck1 & ! sl[ness ( ! proc$ure1 enables u to foll[ ) ease e /age 9 ! =mation ( a p>t+ drop4 ,illu/ration3 ,fig4 #ba4 ,illu/ration3 ,figs4 #ba & #bb4--;,automatically =m$ anil9e drops1 %[+ ! =mation ( droplets f ! neck4 ,& n[ z to ! explanation ( ?is curi\s p]=mance4 ,:5 ! anil9e rea*es ! surface1 & spreads out1 x cools by contact ) ! air m rapidly ?an ! wat] bel[4 ,z x cools1 its d5sity increases1 & soon becomes great] ?an t ( ! wat]1 9 :i* x !n attempts to s9k4 ,! =ces ( surface t5sion prev5t ! :ole ( ! anil9e f fall+--! wat] surface c su/a9 a c]ta9 weight ( ! liquid--b ! surplus weight _c be held1 & !re=e breaks away4 ,b :5 ! deta*$ drop rea*es ! bottom ( ! vessel1 x is w>m$ up aga92 & :5 its temp]ature rises above t ( equi-d5sity x floats up to ! top4 ,& s ! cycle ( op]ations becomes cont9u\s1 ow+ to cool+ tak+ place at ! top & heat+ at ! bottom4 ,p]petual motion1 y might sugge/4 ,no?+ ( ! k9d4 ,p]petual motion means ! cont9u\s p]=mance ( "w )\t any supply ( en]gy2 x does n mean m]ely cont9u\s movem5t4 ,a /eam-eng9e works s long z x is provid$ ) /eam1 & an electric motor s long z x is f$ ) electricity2 b bo? /op :5 ! supply ( en]gy is )drawn4 ,s ) our anil9e drop1 :i* d]ives its en]gy f ! heat ( ! wat]1 & :i* comes to re/ imm$iately ! temp]ature falls bel[ #adg deg4 ,f4 or #fd deg4 ,c4 ,b 9 ord] t ! process ( sep>ation & reunion may cont9ue1 ! cool+ at ! top is q z necess>y z ! heat+ at ! bottom4 ,our anil9e drop is 9 ess5ce a heat-eng9e--al?\gh x does no ext]nal "w--& l all heat-eng9es possesses a s\rce f :i* heat is d]iv$1 & a s9k into :i* heat at a l[] temp]ature is reject$4 ,we might1 ) c]ta9 /ipulations1 "w out an indicator diagram = our liquid eng9e1 b t w\ld be /ray+ too f> f our pres5t subject4 99,automatic ,drops ( o!r ,liquids499--,liquids :i* possess a l[ equi-d5sity temp]ature ) wat] d n =m automatic drops l anil9e1 z ! rate ( cool+ at ! surface is too sl[1 & h5ce ! float+ mass ( liquid does n atta9 a d5sity 9 excess ( t ( ! wat] b5ea?4 ,aceto-acetic e!r1 h[ev]1 behaves l anil9e1 if ! temp]ature ( ! wat] be ma9ta9$ at ab\t #agj deg4 ,f4 7#gg deg4 ,c471 b z ?is liquid is fairly soluble 9 hot wat] fur!r quantities mu/ be add$ dur+ ! progress ( ! exp]im5t4 ,results equal to ^? obta9$ ) anil9e1 h[ev]1 may be secur$ by us+ nitrob5z5e 9 nitric acid ( specific gravity #a4b at #ei deg4 ,f4 7#ae deg4 ,c471 ! acid be+ heat$ to #ahe deg4 ,f4 7#he deg4 ,c472 & "h y see ! yell[ drop p]=m+ its alt]nate asc5ts & desc5ts exactly z 9 ! case ( anil9e & wat]4 ,o!r examples might be giv52 b we may take x z a g5]al rule t :5 ! equi-d5sity temp]ature ( ! liquid & m$ium is above #abe deg4 ,f4 7#eb deg4 ,c471 ! ph5om5on ( ! automatic drop may usually be obs]v$ :5 ! temp]ature is rais$ by #cj deg4 ,f4 7#ag deg4 ,c471 above ?is po9t4 99,liquid ,jets499--,s f> we h be5 obs]v+ ! =mation ( s+le drops1 gr[+ sl[ly at ! end ( a tube1 or break+ away f a l>ge mass ( ! float+ liquid4 ,if1 h[ev]1 we accel]ate ! spe$ at :i* ! liquid escapes1 ! drop has no "t to =m at ! outlet1 & a jet is !n =m$4 ,we are all famili> ) a jet ( wat] escap+ f a tap2 x consi/s ( an unbrok5 column ( ! liquid up to a c]ta9 di/ance1 dep5d+ ^u ! pressure1 b ! l[] "p is brok5 up into a l>ge numb] ( drops1 :i* break away f ! column at a def9ite di/ance f ! tap4 ,!re are _m rem>kable features ab\t jets :i* ,i d n int5d to discuss "h1 z x is only int5d$ to consid] ! mann] 9 :i* ! drops at ! end are =m$4 ,to obs]ve ?is proc$ure1 x is necess>y aga9 to resort to our me?od ( sl[+ d[n ! rate ( =mation1 by all[+ ! liquid to fl[ into a m$ium only slightly inf]ior 9 d5sity4 ,= ?is purpose1 or?otoluid9e fall+ into wat] at ! ord9>y room temp]ature is em95tly satisfactory2 & we see on ! scre5 ! projection ( a pipe1 ) its end "u wat]1 plac$ s t a jet ( or?otoluid9e may be dis*>g$ v]tically d[nw>ds f a /opp]$ funnel4 ,i op5 ! tap slightly at fir/1 & we !n m]ely =m a s+le drop at ! end4 ,n[ x is op5$ m widely1 & y obs]ve t ! drop breaks away "s di/ance bel[ ! outlet1 be+ rapidly succe$$ by ano!r & ano!r 7,fig4 #bc74 ,on /ill fur!r op5+ ! tap ! drops =m at a /ill great] di/ance f ! end ( ! pipe1 & succe$ ea* o!r m rapidly1 s t q a numb] appe> 9 view at any giv5 mom5t 7,figs4 #bd & #be74 ,notice h[ ! drop is di/ort$ by break+ away f ! /ream ( liquid1 & h[ x gradually recov]s its sph]ical %ape dur+ its fall ?r\gh ! wat]4 ,f9ally1 ,i increase ! dis*>ge to su* an ext5t t ! =mation ( ! t]m9al drops is s rapid z to be no long] visible to ! eye1 b appe>s l ! turmoil obs]v$ at ! end ( a jet ( wat] escap+ into air4 ,illu/ration3 ,figs4 #bc1 #bd1 #be4--;,jets ( ,or?otoluid9e1 dis*>g$ "u wat]4 ,illu/ration3 ,fig4 #bf4--,wat] /ret*$ betwe5 a tube & a plate4 99,liquid ,columns499--,a simple exp]im5t w suffice to illu/rate :at is meant by a liquid column4 ,"h is a drop ( wat] hang+ f ! end ( a glass tube4 ,i place x 9 ! lant]n & obta9 a magnifi$ image on ! scre51 & !n br+ up a flat plate ( glass until x j t\*es ! susp5d$ drop4 ,z soon z contact is e/abli%$1 ! wat] spreads outw>ds ov] ! plate1 caus+ ! drop to contract 9 diamet] at or ne> its middle "p1 s t its outl9e resembles t ( a cap/an 7,fig4 #bf74 ,! end ( ! glass tube is n[ connect$ to ! plate by a column ( wat] ( curv$ outl9e1 :i* is q /able if undi/urb$4 ,if1 h[ev]1 ,i gradually raise ! tube1 or l[] ! plate1 ! n>r[ "p ( ! column becomes /ill n>r[]1 & f9ally breaks across4 ,9 ! same way we may produce columns ( o!r liquids2 ^? obta9$ ) visc\s liquids su* z glyc]9e be+ capable ( /ret*+ to a great] ext5t ?an wat]1 b %[+ ! same g5]al *>act]i/ics4 ,a liquid column1 !n1 is 9 reality a support$ drop1 & ! sev]ance effect$ by l[]+ ! support is simil> to t :i* occurs :5 a p5d5t drop breaks away ow+ to its weight4 ,9 our previ\s exp]im5ts we h se5 t 9 ord] to produce l>ge drops ( a giv5 liquid1 ! surr\nd+s %\ld be ( ne>ly ! same d5sity1 s z l>gely to dim9i% ! effective weight ( ! susp5d$ mass4 ,we might !re=e expect t l>ge columns ( liquid c\ld be produc$ "u simil> conditions2 & our conjecture is correct4 ,we may1 = example1 use ! app>atus by means ( :i* l>ge drops ( or?otoluid9e 7 =m$ 7,fig4 #ac71 us+ a %all[ lay] ( wat]1 s t ! l[] end ( ! drop w\ld come into contact ) ! bottom ( ! vessel be=e ! break+ /age 0 rea*$1 & ?us produce1 on a l>ge scale1 ! same result z t we h j a*iev$ by all[+ a hang+ drop ( wat] to t\* a glass plate4 ,?is me?od1 h[ev]1 re/ricts ! diamet] ( ! top ( ! column to t ( ! deliv]y tube1 & 9 ?is respect ! %ape is /ra9$4 ,! rem$y = ?is is to hang ! drop f ! surface ( ! wat]1 :5 a degree ( fre$om is conf]r$ ^u ! upp] "p1 :i* enables ! column to assume a great] v>iety ( %apes4 ,9 ord] to %[ h[ ?is may be accompli%$1 ,i p\r a small quantity ( wat] into ! r\nd$ end ( a wide te/-tube1 :i* is n[ se5 project$ on ! scre51 & !n p\r g5tly d[n ! side a quantity ( e?yl b5zoate1 a liquid slightly d5s] ?an wat]4 ,y obs]ve t ! liquid spreads out on ! surface ( ! wat]1 =m+ a hang+ drop :i* at fir/ is ne>ly hemisph]ical 9 %ape2 b z ,i cont9ue to add ! liquid ! drop gr[s 9 size d[nw>ds1 & f9ally rea*es ! bottom ( ! tube4 ,!re is our liquid column 7,fig4 #bg71 :i* has =m$ itself 9 its own way1 free f ! re/riction impos$ by a deliv]y tube4 ,notice ! graceful curv$ outl9e1 produc$ by a beautiful balance betwe5 ! =ces ( surface t5sion & gravitation2 & notice also h[ ! outl9e may be v>i$ by ! gradual addition ( wat]1 :i* causes ! upp] surface to rise1 & ?us /ret*es ! column 7,fig4 #bh74 ,! middle becomes m & m n>r[ 7,fig4 #bi71 & f9ally breaks across1 leav+ a portion ( ! =m] column hang+ f ! surface1 & ! rema9d]1 9 r\nd$ =m 7,fig4 #cj71 at ! bottom ( ! tube4 ,&1 z usual1 ! p>tition 0 accompani$ by ! =mation ( a small droplet4 ,illu/ration3 ,figs4 #bg1 #bh1 #bi1 #cj4--;,a liquid column /ret*$ upw>ds until brok5 by addition ( wat]4 ,f\r /ages4 ,x is possible1 by us+ o!r liquids1 & diff]5t diamet]s ( vessels1 to produce columns ( a l>ge v>iety ( outl9es4 ,"s liquids spread ov] a great] area on ! surface ( wat] ?an o!rs1 & !re=e produce columns ) wid] tops4 ,"h we see a column ( or?otoluid9e1 :i* has a top diamet] ( #b in*es2 & "h aga91 9 contra/1 is a column ( aceto-acetic e!r1 ! surface diamet] ( :i* is only #a_/b in* 7,fig4 #ca74 ,o!r liquids1 su* z anil9e1 give an int]m$iate result4 ,! l[] diamet] is det]m9$ by ! wid? ( ! vessel2 & h5ce we are able to produce an almo/ endless numb] ( %apes4 ,x is int]e/+ to note h[ work]s 9 glass & pott]y h unconsci\sly imitat$ ^! %apes2 & ,i h "h a v>iety ( articles :i* simulate ! outl9es ( "o or o!r ( ! liquid columns y h j se54 ,x is possible t design]s 9 ^! bran*es ( indu/ry might obta9 useful ideas f a /udy ( liquid columns1 :i* pres5t an almo/ limitless field = ! practical obs]vation ( curv$ =ms4 ,illu/ration3 ,fig4 #ca4--;,a column ( aceto-acetic e!r 9 wat]4 99,communicat+ ,drops499--,!re is a well-kn[n exp]im5t1 :i* "s ( y may h se51 9 :i* two soap-bubbles are bl[n on sep>ate tubes1 & are !n plac$ 9 communication int]nally4 ,if ! bubbles are exactly equal 9 size1 no alt]ation takes place 9 ei!r2 b if unequal1 ! small] bubble %r9ks1 & =ces ! air 9 its int]ior into ! l>g] "o1 :i* !re=e increases 9 size4 ,f9ally1 ! small bubble is resolv$ into a slightly-curv$ sk9 :i* cov]s ! end ( ! tube on :i* x 0 orig9ally bl[n4 ,x is evid5t f ?is exp]im5t t ! pressure p] unit area ex]t$ by ! surface ( a bubble on ! air inside is great] 9 a small ?an 9 a l>ge bubble4 ,! int]nal pressure may be prov$ to v>y inv]sely z ! radius ( ! bubble2 ?us by halv+ ! radius we d\ble ! pressure due to ! ela/ic surface1 & s on4 ,! reciprocal ( ! radius ( a sph]e is call$ its curvature1 & we may !re=e /ate t ! pressure ex]t$ by ! walls ( ! bubble on ! int]ior v>y directly z ! curvature4 ,illu/ration3 ,fig4 #cb4--;,app>atus = communicat+ drops1 ) ext5sions ( unequal l5g? atta*$4 ,we h already se5 t a drop ( liquid possesses an ela/ic surface1 & is practically ! same ?+ z a soap-bubble fill$ ) liquid in/ead ( air4 ,we might !re=e expect ! same results if two susp5d$ drops ( liquid 7 plac$ 9 communication z ^? obs]v$ 9 ! case ( soap-bubbles4 ,& our reason+ is correct1 z we may n[ demon/rate4 ,! app>atus consi/s 7,fig4 #cb7 ( two p>allel tubes1 ea* provid$ ) a tap1 & communicat+ ) a cross-bran* at ! top1 :i* conta9s a res]voir to hold ! liquid us$4 ,ab\t half-way d[n ! p>allel tubes a cross-piece1 provid$ ) a tap1 is plac$4 ,we comm5ce by fill+ ! :ole ( ! sy/em ) ! liquid "u trial1 & ! p>allel tubes equal 9 l5g?4 ,drops are !n =m$ at ! ends ( ea* v]tical tube by op5+ ! taps on ^! 9 turn1 & clos+ aft] suitable drops h be5 =m$4 ,!n1 by op5+ ! tap on ! horizontal cross-piece1 we place ! drops 9 communication & wat* ! result4 ,i h *os5 or?otoluid9e z ! liquid1 & by plac+ ! ends ( ! v]tical tubes "u wat]--:i* at ! temp]ature ( ! room is slightly less d5se ?an or?otoluid9e--,i am able to =m mu* l>g] drops ?an w\ld be possible 9 air4 ,y n[ see a small & a l>ge drop project$ on ! scre52 & ,i n[ op5 ! cross-tap1 s t !y may communicate4 ,notice h[ ! little drop %r9ks until x =ms m]ely a slightly-curv$ prom95ce at ! end ( its tube4 ,x atta9s a position ( re/ :5 ! curvature ( ?is prom95ce is equal to t ( ! n[ enl>g$ drop :i* has swall[$ up ! cont5ts ( ! small] "o4 ,s f> ! result is id5tical ) t obta9$ ) soap-bubbles2 b we c ext5d ! exp]im5t 9 su* a way z to rev]se ! process1 & make ! little drop absorb ! big "o4 ,9 ord] to d ?is ,i fa/5 an ext5sion to "o ( ! tubes1 & =m a small drop deep d[n 9 ! wat]1 & a l>g] "o on ! unext5d$ bran* ne> ! top4 ,:5 ,i op5 ! communicat+ top1 ! sy/em becomes a k9d ( siphon1 ! or?otoluid9e t5d+ to fl[ out ( ! end ( ! long] tube4 ,! t5d5cy ( ! l>ge drop to siphon ov] is oppos$ by ! sup]ior pressure ex]t$ by ! sk9 ( ! small] drop2 b ! =m] n[ prevails1 & ! big drop gradually %r9ks & ! little "o is obs]v$ to gr[ l>g]4 ,x is possible by regulat+ ! dep? at :i* ! small] drop is plac$1 to balance ! two t5d5cies1 s t ! sup]ior pressure due to ! less] drop is equall$ by ! extra d[nw>d pressure due to ! great] l5g? ( ! column ( :i* x =ms ! t]m9us4 ,bo? pressures are num]ically v small1 b are /ill ( suffici5t magnitude to cause a fl[ ( liquid 9 "o or o!r direction :5 n exactly 9 equilibrium4 ,9 ! case ( communicat+ soap-bubbles1 conta9+ air & surr\nd$ by air1 locat+ ! small bubble at a l[] level w\ld n rev]se ! direction ( fl[1 :i* we succe$$ 9 accompli%+ ) liquid drops =m$ 9 a m$ium ( slightly inf]ior d5sity4 ,illu/ration3 ,fig4 #cc4--;,comb9$ drops ( vap\r & liquid4 99,comb9$ ,vap\r & ,liquid ,drops499--,all liquids :5 heat$ give (f vap\r1 ! am\nt increas+ z ! temp]ature rises4 ,! vap\r =m$ 9 ! l[] "p ( ! vessel 9 :i* ! liquid is heat$ rises 9 ! =m ( bubbles1 :i* may cond5se aga9 if ! upp] "p ( ! liquid be cold4 ,:5 ! liquid becomes hot ?r\gh\t1 h[ev]1 ! vap\r bubbles rea* ! surface & break1 all[+ ! cont5ts to escape into ! air above4 ,ev]yone :o has wat*$ a liquid boil+ w be famili> ) ?is process1 b x %\ld be rememb]$ t a liquid may give (f l>ge quantities ( vap\r )\t actually boil+4 ,a di% ( cold wat]1 if expos$ to ! air1 w gradually evaporate away2 :il/ o!r liquids1 su* z petrol & alcohol1 w disappe> rapidly "u ! same circum/ances--& h5ce are call$ volatile liquids4 ,! =mation ( vap\r & its subsequ5t escape at ! surface ( ! liquid1 enable u to produce a v novel k9d ( drop2 if1 in/ead ( all[+ ! bubbles to escape into air1 we cause !m to ent] a second liquid4 ,"h1 = example1 is a col\r$ lay] ( *lor(orm#a at ! bottom ( a beak]1 ) a column ( wat] above4 ,i project ! image ( ! beak] on ! scre51 & !n heat x bel[4 ,! *lor(orm vap\r escapes 9 bubbles2 b notice t ea* bubble c>ries ) x a quantity ( liquid1 torn (f1 z x 71 at ! mom5t ( sep>ation4 ,! vap\r bubbles & _! liquid app5dages v>y 9 size1 b "s ( !m1 y obs]ve1 h an av]age d5sity ab\t equal to t ( ! wat]1 & float ab\t l weight$ balloons4 ,"s rise ne>ly to ! surface1 :]e ! wat] is colde/2 & !n ! vap\r p>tially cond5ses1 ) ! result t its lift+ p[] is dim9i%$1 & h5ce ! drops s9k into ! l[] "p ( ! beak]4 ,b ! wat] is w>m] 9 ?is region1 & consequ5tly ! vap\r bubble increases 9 size & lift+ p[] until aga9 able to lift its load to ! surface4 ,s ! composite drops g up & d[n1 until f9ally !y rea* ! surface1 :5 ! vap\r passes into ! air1 & ! susp5d$ liquid falls back to ! mass at ! bottom ( ! beak]4 ,notice t ! drop ( liquid atta*$ to ea* bubble is elongat$ v]tically4 ,?is is because *lor(orm is a mu* d5s] liquid ?an wat] 7,fig4 #cc74 ,!re is a practical lesson to be drawn f ?is exp]im5t4 ,:5ev] a bubble ( vap\r breaks ?r\gh ! surface ( a liquid1 x t5ds to c>ry ) x "s ( ! liquid1 :i* is dragg$ me*anically into ! space above4 ,9 our exp]im5t ! space 0 occupi$ by wat]1 :i* enabl$ ! bubble to deta* a mu* great] weight ?an w\ld be possible if ! surface ( escape _h be5 cov]$ by air1 :i* is f> less buoyant ?an wat]4 ,b ev5 :5 ! bubbles escape into air1 t9y quantities ( liquid are deta*$2 s t /eam f boil+ wat]1 = example1 is nev] entirely free f liquid4 ,all us]s ( /eam are well acqua9t$ ) ?is fact4 #a ,mono-brom-b5z5e is bett] ?an *lor(orm = ?is exp]im5t1 b is m co/ly4 ,x may be col\r$ ) indigo4 ,*lor(orm may be col\r$ ) iod9e4 99,cond5sation ( ,drops f ,vap\r1--,mi/s1 ,fogs & ,ra9drops499--,! atmosph]e is ! great laboratory = ! manufacture ( drops4 ,x is cont9ually receiv+ wat] 9 ! =m ( vap\r f ! surface ( ! sea1 f lakes1 f runn+ wat]1 & ev5 f sn[ & ice4 ,all ?is vap\r is ultimately turn$ into drops1 & return$ aga9 to ! surface1 & to ?is nev]-ceas+ ex*ange all ! ph5om5a connect$ ) ! precipitation ( moi/ure are due4 ,! atmosph]e is only capable ( hold+ a c]ta9 quantity ( wat] 9 ! =m ( vap\r1 & ! l[] ! temp]ature ! less ! capacity = invisible moi/ure4 ,:5 fully *>g$1 ! atmosph]e is said to be saturat$--a condition realiz$ on ! small scale by air 9 a cork$ bottle conta9+ "s wat]1 :i* evaporates until ! air c hold no m4 ,! maximum weight ( vap\r t c be held by #a cubic metre ( air at diff]5t temp]atures is %[n 9 ! table3-- ---------------------------------------- -------------------------- ,temp]ature4 ,weight ( wat] vap\r 7grammes7 requir$ to ,deg4 ,c4 ,deg4 ,f4 saturate #a cubic metre4 ---------------------------------------- -------------------------- #j #cb #d4h #e #da #f4h #aj #ej #i4c #ae #ei #ab4g #bj #fh #ag4a #be #gg #bb4h #cj #hf #cj4j #ce #ie #ci4b #dj #ajd #ej4f ---------------------------------------- -------------------------- ,x w be se5 f ! table t air on a w>m day 9 summ]1 ) a temp]ature ( #gg deg4 ,f41 c hold ne>ly five times z mu* moi/ure z air at ! freez+ po9t1 or #cb deg4 ,f4 ,! am\nt actually pres5t1 h[ev]1 is usually bel[ ! maximum1 & is record$ = meteorological purposes z a p]c5tage ( ! maximum4 ,?us if ! relative humidity at #gg deg4 ,f4 7 #gj p] c5t41 x w\ld imply t ! weight ( moi/ure 9 #a cubic metre 0 #gj p] c5t4 ( #bb4h grammes2 t is1 ne>ly #af grammes4 ,if #a cubic metre ( air at #gg deg4 ,f41 conta9+ #af grammes ( moi/ure1 7 cool$ to #ej deg4 ,f41 a quantity ( wat] equal to 7#af-i4c7 #f4g grammes w\ld sep>ate out1 z ! maximum cont5t at ! l[] temp]ature is #i4c grammes4 ,precipitation w\ld comm5ce at #ff deg4 ,f41 at :i* temp]ature #a cubic metre is saturat$ by #af grammes4 ,& simil>ly = all /ates ( ! atmosph]e ) respect to moi/ure1 cool+ to a suffici5t ext5t causes deposition ( wat] to comm5ce imm$iately bel[ ! saturation temp]ature1 & ! cold] ! air becomes aft]w>ds ! great] ! am\nt :i* settles out4 ,! temp]ature at :i* deposition comm5ces is call$ ! dew po9t4 ,:5ev] atmosph]ic moi/ure assumes ! liquid =m1 drops are inv>iably =m$4 ,^! may v>y 9 size1 f ! t9y sph]es :i* =m a mi/ to ! l>ge ra9drops :i* accompany a ?und]/orm4 ,b 9 e in/ance x is necess>y t ! air %all be cool$ bel[ its saturation po9t be=e ! sep>ation c comm5ce2 & keep+ ?is fact 9 m9d we c n[ proce$ to demon/rate ! production ( mi/s & fogs4 ,"h is a l>ge flask conta9+ "s wat]1 fitt$ ) a cork ?r\gh :i* is pass$ a glass tube provid$ ) a tap4 ,i pump "s air into x ) a bicycle pump1 & !n close ! tap4 ,z excess ( wat] is pres5t1 ! enclos$ air w be saturat$4 ,n[ a compress$ gas1 on exp&+ into ! atmosph]e1 does "w1 & is !re=e cool$2 & consequ5tly if ,i op5 ! tap ! air 9 ! flask w be cool$1 & z x 0 already saturat$ ! result ( cool+ w be to cause "s ( ! moi/ure to liquefy4 ,accord+ly1 :5 ,i op5 ! tap1 ! int]ior ( ! flask imm$iately becomes fill$ ) mi/4 ,if we exam9e ! mi/ 9 a /rong light by ! aid ( a magnify+ glass1 we obs]ve t x consi/s ( myriads ( t9y sph]es ( wat]1 :i* float 9 ! air1 & only subside v gradually1 ow+ to ! friction betwe5 _! surfaces & ! surr\nd+ air prev5t+ a rapid fall4 ,! small] ! sph]e1 ! great] ! area ( surface 9 proportion to mass1 & !re=e ! sl[] its fall4 ,& s 9 nature1 ! mi/s are =m$ by ! cool+ ( ! atmosph]e by contact ) ! surface1 until1 aft] ! saturation po9t is rea*$1 ! surplus moi/ure settles out 9 ! =m ( t9y sph]es1 :i* float ne> ! surface1 & are dissipat$ :5 ! sun w>ms up ! gr\nd & ! mi/y air1 & ?us enables ! wat] aga9 to be held z vap\r4 ,fogs1 l mi/s1 are compos$ ( small sph]es ( wat] cond5s$ f ! atmosph]e by cool+2 b 9 ^! unwelcome visitors ! region ( cool+ ext5ds to a high] level1 & ! l[]+ ( temp]ature is due to o!r causes ?an contact ) ! cold surface ( ! e>?4 ,9 our popul\s cities1 ! d5sity ( ! fogs is acc5tuat$ by ! pres5ce ( l>ge quantities ( solid p>ticles 9 ! atmosph]e1 :i* arise f ! smoke f coal fires1 & ! abrasion ( ! roads by traffic4 ,we c make a city fog 9 our flask4 ,i bl[ 9 "s tobacco smoke1 & !n pump 9 air z be=e4 ,y w notice t ! smoke1 :i* is n[ dissem9at$ ?r\gh ! air 9 ! flask1 is sc>cely visible2 b n[1 on op5+ ! tap1 ! int]ior becomes mu* d>k] ?an 0 ! case 9 our previ\s exp]im5t4 ,we h produc$ a g5u9e yell[ fog1 t is1 a d5se mi/ col\r$ by smoke4 ,:5 we h le>n$ h[ to aboli% smoke1 & h[ to prev5t du/ aris+ f ! /reets1 our wor/ fogs w be r$uc$ to d5se mi/s1 su* z are n[ met ) on ! sea or on l& remote f l>ge c5tres ( habitation4 ,!re is "o feature common to ! sph]es :i* compose a mi/ or fog1 or inde$ to any k9d ( drop result+ f ! cond5sation ( moi/ure 9 ! atmosph]e4 ,z %[n by ! deeply int]e/+ rese>*es ( ,aitk5 & o!rs1 ea* sep>ate sph]e =ms r\nd a core or nucleus1 :i* is usually a small speck ( du/1 & h5ce an atmosph]e *>g$ ) solid p>ticles l5ds itself to ! =mation ( d5se fogs imm$iately ! temp]ature falls bel[ ! dew-po9t4 ,b du/ p>ticles are n indisp5sable to ! production ( cond5s$ sph]es1 = x has be5 %[n t ! extremely small bodies we call ions1 :i* are electrically *>g$ atoms1 c act z c5tres r\nd :i* ! wat] w collect2 & mu* atmosph]ic cond5sation at high elevations is probably due to ! aid ( ions4#b ,ne> ! surface1 h[ev]1 :]e du/ is ev] pres5t1 cond5sation r\nd ! innum]able specks or motes is ! rule4 ,"h1 = example1 is a jet ( /eam escap+ into air1 =m+ a :ite cl\d compos$ ( a multitude ( small sph]es ( cond5s$ wat]4 ,if n[ ,i all[ ! /eam to ent] a l>ge flask conta9+ air f :i* ! du/ has be5 remov$ by filtration ?r\gh cotton wool1 no cl\d is =m$ 9 ! int]ior1 b in/ead cond5sation takes place at ! end ( ! jet1 f :i* l>ge drops fall1 & on ! cold sides ( ! flask4 ,! cl\d we see 9 du/y air is entirely abs5t1 & ! effect ( solid p>ticles 9 ! process ( cond5sation is ?us %[n 9 a /rik+ mann]4 ,cl\ds are masses ( ?ick mi/ float+ at v>y+ heights 9 ! atmosph]e4 ,on s9k+ into a w>m] lay] ( dry air ! p>ticles ( :i* cl\ds are compos$ w evaporate & vani% f sight4 ,if ! cond5sation cont9ue1 h[ev]1 ! sph]es w gr[ 9 size until ! friction ( ! atmosph]e is unable to arre/ _! fall2 & !n we h ra94 ,& :e!r ! precipitation be v g5tle1 & compos$ ( small drops fall+ sl[ly1 z 9 a ,scot* mi/1 or 9 ! =m ( rapid-fall+ l>ge drops su* z accompany a ?und]/orm1 ! processes at "w are id5tical4 ,e p>ticle ( a mi/ or cl\d1 & e ra9drop1 is =m$ r\nd a nucleus1 & owes its sph]ical %ape to ! t5sion at ! surface4 #b ,mr4 ,c4 ,t4 ,r4 ,wilson has rec5tly devis$ an app>atus = mak+ visible ! tracks ( ioniz+ rays1 by ! cond5sation ( wat] vap\r r\nd ! fre%ly lib]at$ ions4 99,liquid ,cl\ds 9 ,liquid ,m$ia499--,j z ! excess ( moi/ure is precipitat$ f saturat$ air :5 ! temp]ature falls1 s is ! excess ( "o liquid dissolv$ 9 ano!r ?r[n d[n by cool+ bel[ ! saturation temp]ature4 ,moreov]1 a liquid :5 precipitat$ 9 a second liquid appe>s 9 ! =m ( myriads ( small sph]es1 :i* h ! appe>ance ( a d5se cl\d4 ,"h is "s boil+ wat] to :i* an excess ( anil9e has be5 add$1 s t ! wat] has dissolv$ z mu* anil9e z x c hold4 ,anil9e dissolves m freely 9 hot wat] ?an 9 cold1 s t if ,i remove ! flame1 & all[ ! beak] to cool1 ! surplus ( dissolv$ anil9e w settle out4 ,cool+ takes place mo/ rapidly at ! surface1 & y obs]ve :ite /reaks fall+ f ! top into ! int]ior1 :]e !y are w>m$ up & disappe>4 ,soon1 h[ev]1 ! cool+ spreads ?r\gh\t2 & n[ ! /reaks become p]man5t1 & ! wat] becomes opaque1 ow+ to ! ?ick :ite cl\d ( precipitat$ anil9e4 ,! abs5ce ( ! r$ col\r *>act]i/ic ( anil9e is due to ! extremely f9e /ate ( division assum$ 9 ! process4 ,if left = "s h\rs1 ! :ite cl\d s9ks ?r\gh ! wat] to ! bottom ( ! beak]1 :]e ! small p>ticles coalesce & =m l>ge drops1 leav+ ! ov]ly+ wat] q transp>5t4 ,! process is q analog\s to ! precipitation ( moi/ure f ! atmosph]e 9 ! =m ( small sph]es1 :i*1 if undi/urb$1 w\ld gradually s9k to ! gr\nd & leave ! air cle>4 99,ov]heat$ ,drops499--,! temp]ature at :i* a liquid boils1 "u normal conditions1 dep5ds only ^u ! pressure on its surface4 ,?us wat] boil+ 9 air1 :5 ! pressure is #gf c5timetres or #bi4ib in*es ( m]cury1 correspond+ to #ad4g p\nds p] squ>e in*1 possesses a temp]ature ( #ajj deg4 ,c4 or #bab deg4 ,f4 ,at high] elevations1 :]e ! pressure is less1 ! boil+ po9t is l[]2 ?us ,tyndall obs]v$ t on ! summit ( ! ,f9/]a>horn 7#ad1jjj feet7 wat] boil$ at #hf deg4 ,c4 or #ahg deg4 ,f4 ,conv]sely1 "u increas$ pressure1 ! boil+ po9t rises2 s t at a pressure ( #ce p\nds p] squ>e in* wat] does n boil until ! temp]ature rea*es #abe deg4 ,c4 or #beg deg4 ,f4 ,!re are c]ta9 abnormal conditions1 h[ev]1 "u :i* ! boil+ po9t ( a liquid may be rais$ consid]ably )\t any increase 9 ! pressure at ! surface2 & x is !n said to be ov]-heat$4 ,duf\r %[$ t :5 drops ( wat] are float+ 9 ano!r liquid ( ! same d5sity1 !y may become greatly ov]heat$1 & if v small 9 size may atta9 a temp]ature ( #aej deg4 ,c4 or #cjb deg4 ,f41 or ev5 high]1 be=e bur/+ into /eam4 ,9 ord] to provide a m$ium 9 :i* wat] drops w\ld float at ^! temp]atures1 ,duf\r made a mixture ( l9se$ oil & oil ( cloves1 :i* possess$ ! necess>y equi-d5sity temp]ature ) wat]4 ,to demon/rate ?is curi\s ph5om5on1 ,i take a mixture ( #d volumes ( e?yl b5zoate & #a volume ( anil9e1 :i* at #abe deg4 ,c4 or #beg deg4 ,f4 is exactly equal 9 d5sity to wat] at ! same temp]ature4 ,i add to ! mixture two or ?ree cubic c5timetres ( fre%ly-boil$ wat]1 ! temp]ature be+ ma9ta9$ at #abe deg4 ,c4 by surr\nd+ ! vessel ) glyc]9e heat$ by a flame4 ,at fir/ ! wat] s9ks1 b on atta9+ ! temp]ature ( ! mixture x breaks up ) "s viol5ce1 =m+ sph]es ( v>i\s sizes :i* rema9 susp5d$ 9 ! mixture4 ,any portion ( ! wat] :i* has rea*$ ! surface boils vigor\sly1 & escapes 9 ! =m ( /eam2 & "s ( ! l>g] sph]es may be obs]v$ to be giv+ (f /eam1 :i* rises to ! surface4 ,mo/ ( ! sph]es1 h[ev]1 rema9 p]fectly tranquil1 9 spite ( ! fact t ! wat] ( :i* !y are compos$ is _m degrees above its normal boil+ po9t4 ,if ,i p5etrate "o ( ^! sph]es ) a wire1 y notice t x breaks up imm$iately1 ) a rapid g5]ation ( /eam4 ,a complete explanation ( ?is abnormal condition ( wat] is difficult to foll[1 z a numb] ( factors are involv$4 ,"o ( ! contributory causes--?\gh possibly a m9or "o--is ! opposition (f]$ to ! lib]ation ( /eam by ! t5sion at ! surface ( ! sph]es4 ,illu/ration3 ,fig4 #cd4--,sph]oid ( wat] on a hot plate4 99,float+ ,drops on ,hot ,surfaces499--,if a liquid be all[$ to fall 9 small quantity on to a v hot solid1 x does n spread out ov] ! surface1 b =ms into drops :i* run ab\t & gradually evaporate4 ,by c>eful proc$ure1 we may =m a v l>ge1 flatt5$ drop on a hot surface1 & on inve/igation we %all notice "s rem>kable facts4 ,i take a plate ( alum9ium1 ) a dimple 9 ! c5tre1 & make x v hot by means ( a burn]4 ,y see ! upp] surface ( ?is plate project$ on ! scre54 ,i n[ all[ wat] to fall on ! plate drop by drop1 & y he> a hiss+ noise produc$ :5 ea* drop /rikes ! plate4 ,! sep>ate drops ga!r toge!r 9 ! depression at ! c5tre ( ! plate1 =m+ a v l>ge flatt5$ globule4 ,y might h expect$ ! wat] to boil vigor\sly1 b no signs ( ebullition are visible2 & :at is m rem>kable1 ! temp]ature ( ! drop1 9 spite ( its surr\nd+s1 is actually less ?an ! ord9>y boil+ po9t4 ,notice n[ h[ ! drop has comm5c$ to rotate1 & has be5 set into vibration1 caus+ ! edges to become scallop$ 7,fig4 #cd74 ,! drop1 al?\gh n actually boil+1 is giv+ (f vap\r rapidly1 & !re=e gradually dim9i%es 9 size4 ,& n[ ,i want to prove t ! drop is n really t\*+ ! plate1 b float+ above x4 ,to d ?is ,i make an electric circuit conta9+ a cell & galvanomet]1 & connect "o t]m9al to ! plate & place ! o!r 9 ! drop4 ,no movem5t is %[n on ! galvanomet]1 z w\ld be ! case if ! drop t\*$ ! plate & ?us complet$ ! electric circuit4 ,& at close range we c actually see a gap betwe5 ! drop & ! plate1 s t ! evid5ce is conclusive4 ,if n[ ,i remove ! flame--leav+ ! electric circuit intact--& all[ ! plate to cool1 we notice aft] a "t t ! globule flatt5s out sudd5ly & t\*es ! plate1 z %[n by ! deflection ( ! galvanomet]2 & simultane\sly a l>ge cl\d ( /eam arises1 due to ! rapid boil+ :i* occurs imm$iately contact is made4 ,:at we h se5 9 ! case ( wat] is %[n by mo/ liquids :5 pres5t$ to a surface possess+ a temp]ature mu* high] ?an ! boil+ po9t ( ! liquid4 ,a liquid held up 9 ?is mann] above a hot surface is said to be 9 ! sph]oidal /ate1 to di/+ui% x f ! flat /ate usually assum$ by spread+ :5 contact occurs betwe5 ! liquid & ! surface4 ,x is d\btful :e!r any satisfactory explanation ( ! sph]oidal /ate has ev] be5 giv54 ,evid5tly1 ! lay] ( vap\r betwe5 ! plate & ! drop mu/ ex]t a consid]able upw>d pressure 9 ord] to su/a9 ! drop1 b ! exact orig9 ( ?is pressure is difficult to trace4 ,,lecture ,,iii 99,spread+ ( ,oil on ! ,surface ( ,wat]499--,if a small drop ( oil be plac$ on ! surface ( wat] x w be obs]v$ to spread imm$iately until x =ms a ?9 lay] cov]+ ! surface4 ,if a fur!r addition ( ! oil be made1 globules w be =m$1 :i*1 z y n[ see ^u ! scre51 rema9 float+ on ! surface4 ,! spread+ ( ! oil 9 all directions f ! place on :i* ! small quantity ( oil 0 dropp$ is due to ! sup]ior surface t5sion ( wat]1 :i* pulls ! oil outw>ds4 ,! surface t5sion ( ! oil opposes t ( ! wat]1 & w\ld prev5t ! drop f spread+ 7 x n ov]come by a great] =ce4 ,! result is ! same z w\ld be obs]v$ if ! c5tre or any o!r "p ( a /ret*$ rubb] disc 7 weak5$2 ! weak "p w\ld be /ret*$ 9 all directions1 & ! re/ ( ! disc w\ld %r9k t[>ds ! sides4 ,:5 ! oil has spread out1 h[ev]1 & contam9at$1 z x 71 ! surface ( ! wat]1 ! surface t5sion is r$uc$1 & is n suffici5tly /rong to /ret* out a fur!r quantity ( oil1 :i*1 if add$1 rema9s 9 ! =m ( a float+ globule4 ,illu/ration3 ,fig4 #ce4--;,=ces act+ on a float+ globule4 ,let u /udy ! =ces at "w on ! float+ globule a little m closely4 ,its upp] surface is 9 contact ) air1 & ! surface t5sion t5ds1 z usual1 to r$uce ! area to a m9imum4 ,! top ( ! globule is n flat1 b curv$ 7,fig4 #ce71 & its surface meets t ( ! wat] at an angle2 & ! c\nt]-pull ex]t$ aga9/ ! /ret*+-pull ( ! wat] surface is n horizontal1 b incl9$ 9 ! direction ( ! angle ( contact1 z %[n by ! l9e ,b4 ,! "u "p ( ! globule is also curv$1 & meets ! wat] surface f bel[ at an angle2 & "h also is ex]t$ a pull 9 opposition to t ( ! wat] surface1 diff]5t 9 magnitude to ! =ce at ! upp] surface1 b also direct$ at ! angle ( contact z %[n by ! l9e ,c4 ,?is t5sion at ! jo9+ surface ( two liquids is call$ ! int]facial t5sion1 to di/+ui% x f t ( a surface 9 contact ) air4 ,act+ aga9/ ^! two t5sions is t ( ! wat]1 :i* is direct$ horizontally along ! surface1 z %[n by ! l9e ,a4 ,! l9es ,a1 ,b1 & ,c indicate ! =ces act+ at a s+le po9t2 b ! same =ces are at "w at e po9t r\nd ! circle ( contact ( ! globule & ! surface ( ! wat]4 ,& !re=e ! t5d5cy on ! "p ( ! wat] t5sion is to cause ! globule to spread out 9 all directions1 :]eas ! o!r two t5sions t5d to prev5t any enl>gem5t ( its surface4 ,! result dep5ds ^u ! magnitudes & directions ( ! conflict+ =ces4 ,we c imag9e a k9d ( tug-(-w> tak+ place1 9 :i* "o conte/ant1 ,a1 is oppos$ to two o!rs1 ,b & ,c1 all pull+ 9 ! directions indicat$ 9 ,fig4 #ce4 ,al?\gh ,a is s+le-h&$1 he has ! advantage ( a /raight pull1 :]eas ,b & ,c c only ex]t _! /r5g? at an angle1 & ! l>g] ! angle ! m !y are h&icapp$4 ,if ,a be m p[]ful ?an ,b & ,c1 ! globule w spread2 b ! result ( ! spread+ is to dim9i% ! angles at :i* ! pulls ( ,b & ,c are incl9$ to ! surface1 & h5ce _! effective opposition to ,a w be increas$4 ,moreov]1 ! spread+ ( ! liquid dim9i%es ! surface t5sion ( ! wat]--t is1 weak5s ,a--& h5ce x becomes possible = ,b & ,c to prevail & draw back ! surface ( ! globule :i* ,a _h previ\sly /ret*$4 ,if1 9 spite ( ^! disabilities1 ,a %\ld /ill be ! /rong]1 ! globule w be /ret*$ until x cov]s ! :ole surface2 :]eas if ,b & ,c ov]come ,a1 ! globule w %r9k1 increas+ ! angles at :i* ,b & ,c op]ate1 & !re=e r$uc+ _! effective pulls1 until _! comb9$ /r5g? is equal to t ( ,a1 :5 ! globule w rema9 at re/4 ,be>+ ^! facts 9 m9d1 we c und]/& :y a small drop ( oil plac$ on a clean wat] surface spreads across2 = 9 ?is case ,a is /rong] ?an ,b & ,c comb9$4 ,b :5 ! surface ( ! wat] is cov]$ ) a lay] ( oil1 ,a is weak5$1 & c no long] ov]come ! oppos+ pulls ( ,b & ,c4 ,h5ce a fur!r drop ( oil p\r$ on to ! surface rema9s 9 ! =m ( a globule4 99,movem5ts due to ,solubility499--,:5 small fragm5ts ( camphor are plac$ on ! surface ( wat] "s rem>kable movem5ts are se54#c ,! bits ( camphor move ab\t ) great rapidity ov] ! surface1 & g5]ally1 9 addition1 %[ a rapid rot>y motion4 ,! explanation usually giv5 is t ! camphor dissolves 9 ! wat] at ! po9ts ( contact =m+ a solution :i* possesses a less surface t5sion ?an pure wat]4 ,?is solution is 9 consequ5ce /ret*$ by ! t5sion ( ! re/ ( ! surface1 & ! camphor float+ on its solution is !re=e made to move 9 ! direction ( ! l9e along :i* ! /ret*+ =ce happ5s to be ! greate/4 ,b ! camphor cont9ues to dissolve :]ev] x goes1 & is !re=e cont9u\sly pull$ ab\t z a result ( ?is int]play ( t5sions4 ,t\*+ ! surface ) a wire :i* has be5 dipp$ 9 oil imm$iately arre/s ! movem5ts1 ow+ to ! t5sion ( ! wat] be+ dim9i%$ to su* an ext5t by ! sk9 ( oil t x is no long] compet5t to /ret* ! "p on :i* ! camphor floats4 ,no d\bt ?is explanation is correct s f> z x goes1 b x is highly probable t :5 ! float+ sub/ance dissolves1 o!r =ces are call$ into action 9 addition to ! t5sions4 #c ,^! movem5ts 7 fir/ record$ by ,romieu 9 #agdh & 7 ascrib$ by him to electricity4 ,illu/ration3 ,fig4 #cf4--;,anil9e globules on a wat] surface4 99,movem5ts ( ,anil9e ,globules on a ,wat] ,surface499--,if we all[ a small quantity ( anil9e to run on to ! surface ( wat]1 x =ms itself into a numb] ( float+ globules4 ,i n[ project on ! scre5 a wat] surface on :i* a little anil9e has be5 p\r$1 & we are ?us enabl$ to wat* ! movem5ts :i* occur4 ,all ! globules appe> to be twit*+ or %udd]+2 & if y obs]ve closely y w notice ! surface ( ea* globule /ret*+ & recoil+ alt]nately4 ,! recoil is accompani$ by ! projection ( t9y globules f ! rim1 :i* becomes scallop$ :5 ! globule is /ret*$4 ,! small globules ?r[n (f appe> to be =m$ f ! protub]ances at ! edge 7,fig4 #cf71 & aft] leav+ ! ma9 globule !y spread out ov] ! surface1 or dissolve4 ,?is process cont9ues = a long "t1 gradually dim9i%+ 9 vig\r1 until small /ation>y globules are left float+ on ! surface1 :i* is n[ cov]$ ) a sk9 ( anil9e4 ,?is action is 9 /rik+ contra/ to ! tranquil =mation ( float+ globules ( oil1 & calls = "s special comm5t4 ,let u recall aga9 ! ?ree =ces at "w at ! edge ( a float+ globule 7,fig4 #ce74 ,! surface t5sion ( ! wat]1 act+ horizontally1 t5ds to /ret* ! globule1 & is successful mom5t>ily 9 ov]com+ ! oppos+ t5sions1 ea* ( :i* pulls at an angle to ! surface4 ,enl>gem5t ( ! upp] surface ( ! globule1 h[ev]1 r$uces ! angles at :i* ! t5sions ,b & ,c act1 & 9 consequ5ce _! effective /r5g? is increas$4 ,! spread+ ( ! anil9e ov] ! wat] surface dim9i%es ! pull ,a1 :i* ,b & ,c comb9$ n[ ov]come1 & h5ce ! surface ( ! globule %r9ks aga94 ,= "s unexpla9$ reason bo? ! /ret*+ & recoil ( ! globule occur sudd5ly1 !re be+ an int]val ( repose betwe5 ea*1 & ^! j]ky movem5ts result 9 small portions ( ! rim be+ deta*$1 ea* ( :i* =ms a sep>ate small globule4 ,! anil9e :i* spreads ov] ! surface ( ! wat] dissolves1 & ! wat] t5sion ,a1 :i* _h be5 enfeebl$ by ! pres5ce ( ! anil9e sk91 recov]s its =m] /r5g?1 & aga9 /ret*es ! globule2 & s ! :ole process is repeat$4 ,:5 ! surface ( ! wat] becomes p]man5tly cov]$ ) a sk91 :i* occurs :5 ! top lay] is saturat$ ) anil9e1 ! globule rema9s at re/1 & has su* a %ape t ! t5sions ,b & ,c act at angles :i* enable !m j to balance ! weak5$ pull ( ,a4 ,:y ! edge ( ! globule becomes ind5t$ dur+ ! movem5ts1 & :y ^! movem5ts are spasmodic in/ead ( gradual1 has n be5 cle>ly made out4 ,x is int]e/+ to recall t a sph]oid ( liquid on a hot plate also possesses a scallop$ edge1 & x may be t ! two ph5om5a h some?+ 9 common4 ,illu/ration3 ,fig4 #cg4--,or?otoluid9e globules on a wat] surface4 99,movem5ts ( ,or?otoluid9e & ,xylid9e #a-c-d on a ,wat] ,surface499--,we w n[ obs]ve1 by ! aid ( ! lant]n1 movem5ts ( globules m /rik+1 & c]ta9ly m puzzl+1 ?an ^? ( anil9e4 ,i place on ! surface ( ! wat] a quantity ( a special sample ( or?otoluid9e1 & y see t imm$iately a numb] ( globules are =m$ :i* are end[$ ) rem>kable activity4 ,!y become ind5t$ at "o side1 & !n d>t across ! surface at a great spe$1 usually break+ into two z a result ( ! viol5t action 7,fig4 #cg74 ,!n foll[s a %ort p]iod ( re/1 :5 sudd5ly1 z if 9 response to a signal1 all ! l>g] globules aga9 become ind5t$1 =m+ %apes l kidneys1 & aga9 %oot across ! surface1 break+ up into small] globules4 ,notice t ! v small globules rema9 at re/2 x is only ^? above a c]ta9 size t display ?is rem>kable activity4 ,a film ( ! liquid =ms on ! wat]1 & ! action gradually becomes m int]mitt5t1 ceas+ altoge!r :5 a sk9 is well e/abli%$1 & ! l>ge globules h sub-divid$ into v small ones4 ,my sample ( or?otoluid9e is some:at unique1 z o!r specim5s ( ! liquid1 obta9$ f ! same & o!r s\rces1 d n %[ ! same lively *>act]i/ics4 ,z 9 ! case ( camphor1 t\*+ ! surface ) a drop ( oil arre/s ! movem5ts imm$iately4 ,! organic liquid xylid9e #a-c-d1 h[ev]1 exhibits ! same movem5ts1 z y n[ see on ! scre52 &1 if any?+1 is ev5 m active ?an ! or?otoluid9e previ\sly %[n4 ,x may be add$ t occasional samples ( anil9e %[ simil> movem5ts1 b ( less int5sity4 ,n[ if ,i am ask$ to expla9 ^! extraord9>y movem5ts1 ,i am b\nd to confess my inability to d s at pres5t4 ,:y %\ld ! globules become ind5t$ on "o side only8 ,! two t5sions act+ at ! edge 9 opposition to ! wat] t5sion are at "w all r\nd ! globule1 & x is n easy to see :y !y %\ld prevail to su* a m>k$ degree at "o spot only4 ,! movem5t across ! surface1 if we foll[$ our previ\s explanations1 w\ld be due to ! sup]ior pull ( ! wat] t5sion beh9d ! globule1 opposite ! ind5t$ "p2 al?\gh to look at x w\ld seem z if "s s+le =ce produc$ ! ind5tation & pu%$ ! globule along bodily4 ,are !re local weaknesses 9 ! t5sion ( ! wat]1 &1 if s1 :y %\ld su* weak spots =m simultane\sly ne> ea* globule1 caus+ ea* to move at ! same mom5t8 ,any explanation we may give z to ! orig9 ( ! cavity 9 ! side ( ! globule does n suffice to acc\nt = ! int]mitt5t "* ( ! movem5t1 & its simultane\s occurr5ce ov] ! :ole surface4 ,we mu/ !re=e leave ! problem at pres5t1 & tru/ to future inve/igation to provide a solution4 ,illu/ration3 ,,fig4 #ch4--,resolution ( a float+ sk9 into globules4 99,production ( ,globules f ,films499--,:5 a film ( oil spreads ov] a wat] surface x sometimes rema9s z su* indef9itely4 ,c]ta9 o!r liquids1 h[ev]1 =m films :i* aft] a %ort int]val break up into globules1 & ! process ( transition is at once /rik+ & beautiful4 ,9 ord] to %[ x1 ,i project a wat] surface on ! scre51 & p\r on to x a v small quantity ( dime?yl-anil9e--an oily liquid relat$ to b di/9ct f ord9>y anil9e4 ,x spreads out into a film ( irregul> outl9e1 :i* floats quietly = a %ort "t4 ,soon1 h[ev]1 ind5tations are =m$ at ! edges1 :i* p5etrate ! film1 & f ! sides ( ! ind5tations bran*es spread :i* 9 turn become bran*$2 & %ortly ! :ole film becomes ramifi$1 resembl+ a mass ( coral1 or1 to use a m homely illu/ration1 a jig-saw puzzle 7,fig4 #ch74 ,! v>i\s bran*es jo9 9 num]\s places1 cutt+ (f small isl&s f ! film2 & imm$iately ea* isl& becomes circul> 9 outl9e--& ! resolution into globules is complete4 ,we h witness$ "o ( ! beauty-sights ( ,nature4 ,! same me?od ( globule =mation is %[n by nitro-b5zol & qu9ol9e1 & z ! action is m gradual 9 ! case ( ! latt] sub/ance1 ,i %[ x 9 ord] t we may /udy ! process 9 great] detail4 ,notice ! =mation ( ! ind5tations & _! subsequ5t bran*+2 & also t holes =m 9 ! sk9 f :i* bran*+s also proce$4 ,9 ?is in/ance ! film is brok5 up 9 sections1 b ! action cont9ues until no?+ b globules rema9 on ! surface4#d ,x is n easy to see :y ! canals ( wat] p5etrate ! film & split x up into small sections1 nor :y entry takes place at c]ta9 po9ts on ! edge 9 pref]5ce to o!rs4 ,"s ord]ly int]play ( =ces1 n yet prop]ly und]/ood1 gives rise to ! action2 & a satisfactory explanation has yet to be giv54 #d ,! break+-up ( films on ! surface ( wat] 0 fir/ notic$ by ,toml9son ab\t #ej ye>s ago4 ,he us$ ess5tial oils1 & call$ ! patt]ns cohesion figures4 99,network =m$ f a ,film499--,a fur!r example ( ! break+ up ( a film is furni%$ by c]ta9 oils d]iv$ f coal-t>1 ! result 9 ?is case be+ ! =mation ( a network or cellul> /ructure4 ,i place on ! surface ( wat] 9 a glass di% a small quantity ( t>-oil1 & project x on ! scre54 ,x spreads out at fir/ into a ?9 film1 :i*1 by reflect$ light1 %[s a gorge\s display ( col\rs4 ,aft] a %ort "t1 little holes make an appe>ance 9 ! film1 & ^! holes gradually increase 9 size until ! :ole ( ! film is honeycomb$ 7,fig4 #ci71 ! oil hav+ be5 heap$ up into ! walls :i* divide ! sep>ate comp>tm5ts4 ,"h aga9 ! accept$ views on surface t5sion d n appe> compet5t to expla9 ! action4 ,x appe>s to be ! case t mo/ films on ! surface ( wat] %[ ?is t5d5cy to p]=ation1 :i* may be due to inequalities 9 ! ?ickness ( ! film1 or 9 ! di/ribution ( ! /ra9 to :i* x is subject$4#e #e ,an int]e/+ discussion on cellul> /ructures ( ?is type may be f\nd 9 ,nature1 ,april #af to ,june #aa1 #aiad4 ,illu/ration3 ,fig4 #ci4--,network =m$ f a film ( t>-oil on ! surface ( wat]4 ,illu/ration3 ,fig4 #dj4--,qu9ol9e r+s & p]=at$ plates4 99,qu9ol9e ,r+s499--,ref]5ce has already be5 made to ! break+-up ( a qu9ol9e film into globules4 ,b if we exam9e ! surface ab\t half an h\r aft] ! =mation ( ^! globules1 we f9d t ea* has be5 p]=at$ 9 ! c5tre1 =m+ a r+ or annulus 7,fig4 #dj74 ,"s ( ! l>g] globules h und]gone p]=ation 9 sev]al places1 =m+ honeycomb$ plates4 ,^! r+s & plates1 :i* y n[ see project$ on ! scre51 rema9 un*ang$1 & app>5tly repres5t ! f9al /age ( equilibrium "u ! action ( ! v>i\s =ces4 ,qu9ol9e1 s f> z obs]vations h be5 made1 appe>s to be unique 9 respect to ! =mation ( /able r+s f globules4 ,illu/ration3 ,fig4 #da4--,! exp&+ globule4 99,exp&+ ,globules499--,i n[ wi% to %[1 by an exp]im5t1 h[ s5sitive a float+ globule is to di/urbances 9 ! exi/+ t5sions1 :i* ma9ta9 x at re/4 ,on ! scre5 is project$ a globule ( dime?yl-anil9e1 float+ tranquilly on ! surface ( wat]4 ,i n[ all[ a small drop ( qu9ol9e to fall ^u x1 & imm$iately x spreads out ov] ! surface1 =m+ a hole 9 its c5tre 7,fig4 #da71 aft] :i* x gradually resumes its =m] %ape4 ,sometimes ! action is s viol5t t ! globule is split up into sev]al portions1 :i*1 h[ev]1 jo9 toge!r aga9 aft] a %ort "t4 ,9 ord] to expla9 ?is action1 we mu/ aga9 ref] to ! ?ree t5sions op]at+ on ! globule 7,fig4 #ce74 ,:5 9 equilibrium1 ,a is balanc$ by ! jo9t pull ( ,b & ,c2 & h5ce if ei!r ( ! latt] be weak5$1 ,a w pr$om9ate & /ret* ! globule4 ,9 our exp]im5t x is ! int]facial t5sion1 ,c1 :i* has be5 dim9i%$ 9 /r5g?1 z we may n[ prove by a second exp]im5t4 ,9 ?is in/ance ,i float on ! wat] surface a globule ( lubricat+ oil1 ) :i* qu9ol9e does n readily mix1 & :i* does n act s imm$iately z dime?yl-anil9e4 ,on all[+ ! drop ( qu9ol9e to fall into x1 no action is obs]v$ until ! drop has re/$ on ! junction ( ! oil & wat] = a %ort "t2 b :5 x has p5etrat$ ! int]face ! oil globule sudd5ly spreads ov] ! wat] surface1 & ) su* viol5ce z to deta* sev]al portions f ! ma9 globule4 ,m]ely t\*+ ! upp] surface ( ! oil ) a rod moi/5$ ) qu9ol9e has no effect1 & h5ce ! result is due to ! weak5+ ( ! int]facial t5sion4 ,a simil> effect is obta9$ :5 qu9ol9e is dropp$ into a globule ( anil9e1 & may be obta9$ ) v>i\s o!r liquids4 99,attraction betwe5 ,float+ ,globules4--,! ,dev\r+ ,globule499 ,:5 globules ( diff]5t liquids are float+ on ! same wat] surface1 a t5d5cy to coalesce is sometimes notic$1 b is by no means g5]al4 ,i w %[ "o example :i* possesses /rik+ features1 %[+ z x does ! rem>kable results :i* may be br\ght ab\t by surface =ces4 ,fir/ ( all1 we =m a numb] ( active or?otoluid9e globules on ! surface ( a di% ( wat]1 :i* y see wriggl+ ab\t 9 _! *>act]i/ic fa%ion4 ,aft] _! activity has subsid$ some:at1 ,i float on to ! surface a l>ge globule ( dime?yl-anil9e4 ,attraction ( "s k9d is at once app>5t1 = ! ne>e/ globule ( or?otoluid9e imm$iately approa*es ! intrud]4 ,& n[ comes ! process ( absorption4 ,! l>ge globule ( dime?yl-anil9e develops a protub]ance 9 ! direction ( its victim 7,figs4 #db & #dc71 & ! small globule ( or?otoluid9e coalesces ) ?is feel]1 :i* !n %r9ks back into ! l>ge globule1 convey+ ) x ! entangl$ or?otoluid9e4 ,?is1 h[ev]1 by no means satisfies ! dev\r+ globule1 z a second victim is at once appropriat$ 9 ! same mann]2 & y w notice a nibbl+ process at "w r\nd ! edges cont9u\sly1 :i* is due to ! absorption ( ! small] globules ( or?otoluid9e4 ,! action cont9ues until ! :ole ( ! surface has be5 cle>$ ( or?otoluid9e1 aft] :i* ! l>ge globule floats tranquilly 9 ! c5tre ( ! vessel1 app>5tly re/+ aft] its heavy meal4 ,! int]action ( ! =ces :i* gives rise to ?is ph5om5on is difficult to fa?om2 !re are no d\bt sev]al t5sions1 con/antly *ang+ 9 magnitude1 :i* 9 ! result cause ! liquids ( ! l>ge & small globules to int]m+le4 ,sep>ate globules ( a s+le liquid sometimes unite 9 ?is mann]1 b ?is is n common1 x be+ m usual = ! scatt]$ units to rema9 ap>t4 ,illu/ration3 ,fig4 #db4--,! dev\r+ globule4 ,five /ages4 ,illu/ration3 ,fig4 #dc4--,photograph ( "o globule absorb+ ano!r4 99,analogies ( ,surface ,t5sion ,ph5om5a ) ,life499--,:5 we wat* ! movem5ts ( globules on ! surface ( wat]1 ! resemblance to ! antics ( ! l[] =ms ( life imm$iately occurs to our m9ds4 ,n[ ,i d n int5d "h to intrude any op9ion on ! mu*-discuss$ subject ( ! ,orig9 ( ,life1 b m]ely to po9t out t c]ta9 ph5om5a1 usually suppos$ to be associat$ only ) liv+ ?+s1 may result f ! int]play ( surface t5sions4 ,9 our exp]im5ts we h witness$ expansive & contractile motion 7anil9e globules on wat]72 movem5t ( translation1 ( a v vigor\s k9d 7xylid9e & or?otoluid9e globules72 incorporation ( ext]nal matt]1 or fe$+ 7dime?yl-anil9e absorb+ or?otoluid9e7--we are gett+ q famili> ) ^! long names n[--1 splitt+ up ( masses1 or division 7sk9s ( qu9ol9e1 etc41 break+ up into bran*$ portions1 & sub-division ( l>ge globules72 & =mation ( cellul> /ructure 7t>-oil on wat]74 ,& ! conclusion we may legitimately draw is ?is3 t me*anical =ces may acc\nt = _m obs]v$ ph5om5a 9 connexion ) life :i* =m]ly 7 attribut$ to ! action ( vital =ces4 ,mod]n biological rese>* all po9ts 9 ! same direction1 & x seems probable t ! op]ations ( ! animate & inanimate are controll$ by ! same =ces4 ,b ! my/]y ( ,life /ill rema9s4 99,conclusion499--,i h endeav\r$ 9 ^! lectures to br+ to y\r notice "s ( ! rem>kable results :i* may be produc$ by ! use ( wat] & a few o!r liquids1 & ! sci5tific conclusions :i* may be drawn f !m4 ,x may be t ! ph5om5a we h consid]$ h little or no comm]cial application2 b sci5ce has o!r uses 9 addition to its fruitful alliance ) comm]ce4 ,! /udy ( ! me?ods by :i* ,nature a*ieves h] ends /imulates ! imag9ation & quick5s ! p]ceptions1 & is !re=e ( ! highe/ educational value4 ,x is a great sci5tific a*ievem5t to run a railway to ! summit ( ! ,jungfrau1 b we %\ld n envy ! m5tal condition ( ! individual to :om t glori\s m\nta9 appeal$ only ?r\gh ! railway divid5ds4 ,& ,i tru/ t we %all nev] become s imbu$ ) ! indu/rial aspects ( sci5ce1 z to less5 our appreciation ( ! works ( ,nature1 :e!r manife/$ 9 ! sn[-clad peak or ! equally wond]ful drop ( wat]4 ,,app5dix ,app>atus & ,mat]ials requir$ = ,exp]im5ts on ,drops & ,globules4 99,vessels499--,= direct obs]vation ( liquid sph]es1 l>ge drops1 etc41 beak]s ab\t #f in*es 9 height & #d in*es 9 diamet] are suitable4 ,x mu/ be rememb]$1 h[ev]1 t a beak] conta9+ wat] behaves l a cyl9drical l5s1 & h5ce objects 9 ! int]ior appe> di/ort$ 9 %ape4 ,9 ord] to obs]ve ! true dim5sions1 flat-sid$ vessels mu/ be us$1 9 :i* ! faces are ( uni=m ?ickness4 ,glass batt]y-vessels1 :i* are made ( a s+le piece ( glass1 h sides ( irregul> ?ickness1 & are n to be recomm5d$4 ,a useful =m ( vessel is "o 9 :i* ! bottom & edges are made ( copp]1 ! sides be+ =m$ ( w9d[s ( plate glass cem5t$ to ! copp] framework4 ,wat] may be boil$ 9 su* a vessel )\t dang] to ! glass1 />t+ ) cold wat]2 x is n advisable to p\r hot wat] into ! cold vessel1 h[ev]1 z ! glass may crack4 ,suitable dim5sions = a vessel ( ?is k9d are #f in*es high1 & #d in*es 9 wid? & ?ickness4 ,a beak] conta9+ wat]1 9 :i* drops are =m$ may be plac$ 9 ?is squ>e vessel1 & surr\nd$ by wat]1 :5 di/ortion w be abs5t2 & ! :ole ( ! cont5ts may be kept hot--z requir$1 = example1 ) ! automatic anil9e drop4 ,x is be/ to conduct ! exp]im5ts 9 beak]s imm]s$ z describ$1 z ! mat]ials us$ may !n be easily recov]$ )\t hav+ to clean out ! flat vessel4 ,= ! =mation ( liquid columns1 te/-tubes1 ( diamet] #a to #b in*es1 or small beak]s1 may be us$4 ,te/-tubes provid$ ) a foot1 :i* w /& upright1 are mo/ satisfactory2 & ! true %ape may be se5 by imm]s+ ! te/-tube or beak] 9 wat] 9 a flat-sid$ vessel ( ! =m describ$ above4 ,! effect ( heat on ! %ape ( ! column may be obs]v$ by w>m+ ! wat] 9 ! vessel4 ,! c5trifugoscope 7,fig4 #g7 & ! app>atus depict$ 9 ,figs4 #h1 #ac1 & #cb1 may be procur$ f ! mak]s1 ,messrs4 ,a4 ,gall5kamp ,co41 ,sun ,/reet1 ,e4,c4 ,exp]im5ts ) sk9s & globules may be conduct$ 9 beak]s ( ab\t #d in*es diamet]1 or 9 small porcela9 photographic di%es4 ,if int5d$ = lant]n projection %all[ cells1 ) a bottom ( plate glass1 are necess>y1 & may be obta9$ f deal]s 9 sci5tific app>atus4 99,mat]ials499--,suffici5t quantities ( ! v>i\s liquids us$ may be procur$ f deal]s 9 *emicals at a small co/4 ,anil9e & or?otoluid9e1 :i* figure l>gely 9 ! exp]im5ts1 %\ld be obta9$ 9 ! comm]cial =m1 :i* is ! *eape/ & mo/ suitable4 ,! rema9+ liquids %\ld be ( ! v>iety describ$ z pure 9 ! catalogues4 ,:5 us$ = ! =mation ( films1 !y %\ld be kept 9 bottles 9 :i* ! glass /opp] is prolong$ into a tap]$ rod1 :i* dips into ! liquid1 & :i*1 on removal1 c>ries a conv5i5t quantity ( liquid to drop on to ! wat] surface4 ,accessories su* z glass rods1 plates1 tub+ ( v>i\s diamet]s1 ?9 copp] wire1 & an alum9ium plate = ! sph]oidal /ate1 c be obta9$ f any deal] 9 app>atus2 & ! same applies to clamp-/&s = hold+ funnels1 etc4 99,wat]499--,ord9>y tap-wat] suffices = all ! exp]im5ts describ$1 & = "w ) films & globules is sup]ior to di/ill$ wat]1 :i* (t5 possesses a surface s greasy z to ret>d or ev5 entirely prev5t ! desir$ result4 ,all exp]im5ts conduct$ on ! surface ( wat] %\ld be p]=m$ 9 a clean vessel :i* has be5 r9s$ out sev]al times ) tap-wat] be=e fill+4 99,lant]n ,projection499--,9 demon/rat+ ! ph5om5a to an audi5ce1 a lant]n may be us$ to advantage4 ,x %\ld be ( ! type n[ procurable1 :i* is arrang$ = ! projection ( exp]im5ts conduct$ ei!r 9 a horizontal or v]tical position1 by ! use ( ! electric arc or o!r suitable s\rce ( light4 ,flat-sid$ vessels are ess5tial = ! successful projection ( views ( objects 9 a v]tical position2 & = %[+ globules1 etc41 on ! surface ( wat]1 bett] def9ition is secur$ if cells ) plate-glass bottoms are us$ in/ead ( vessels made ( a s+le piece ( glass4 ,! au?or has g5]ally us$ a ,k]%aw lant]n = lecture purposes1 ) q satisfactory results4 ,?is lant]n may also be adapt$ = project+ solid objects by reflect$ light--z1 = example1 a hot plate on :i* a sph]oid ( wat] is float+ 7,fig4 #cd74 ,! contrivance kn[n z ! ,mirrorscope may also be us$1 ) slight modification1 = produc+ a magnifi$ image ( solid objects on ! scre54 ,,index ,a ,,page ,aceto-acetic e!r1 automatic drops (1 4 4 4 #cg columns (1 4 4 4 4 4 4 #dd ,anil9e1 automatic drops (1 4 4 4 4 #cc equi-d5sity temp]ature (1 4 4 4 #ag films or sk9s1 4 4 4 4 4 #ai globules1 movem5ts (1 4 4 4 #fc ,anisol1 4 4 4 4 4 4 4 4 #ai ,area ( /ret*$ surfaces1 4 4 4 4 4 #g ,b ,b\nd>y surface ( two liquids1 4 4 4 4 #f ,butyl b5zoate1 4 4 4 4 4 4 4 #ai ,c ,camphor1 movem5ts ( on ! surface ( wat]1 4 #fc ,c5trifugoscope1 4 4 4 4 4 4 #ad ,*lor(orm1 composite drops (1 4 4 4 4 #dh ,d ,dime?yl-anil9e1 sk9 ( on wat]1 4 4 4 #fh ,div+ drop1 4 4 4 4 4 4 4 #bb ,droplet1 =mation (1 4 4 4 4 #bh1 #cd ,drops ( liquid1 app>atus =1 4 4 4 4 #bg automatic1 4 4 4 #cc1 #cg comb9$ ) vap\r1 4 4 #dg communicat+1 4 4 4 #dd cond5sation ( f vap\r1 4 #di float+ on hot surface1 4 4 #eg =mation (1 4 4 #bd1 #cc1 #cg ov]heat$1 4 4 4 4 #ee %apes (1 4 4 #aj1 #bi1 #cj1 #ca ,e ,ela/ic sk9 ( liquids1 4 4 4 4 4 #e ,equi-d5sity temp]atures1 4 4 4 #af1 #ag1 #ai ,e?yl b5zoate1 columns (1 4 4 4 4 #db ,f ,fogs1 4 4 4 4 4 4 4 4 #eb ,g ,globule1 =ces act+ on1 4 4 4 4 4 #fa ! dev\r+1 4 4 4 4 4 #gd ,globules1 attraction betwe51 4 4 4 4 #gc exp&+1 4 4 4 4 4 4 #gb production f films1 4 4 4 4 #fi surface movem5ts on wat]1 4 4 #fc1 #ff ,gold5 syrup1 exp]im5t )1 4 4 4 4 #h ,i ,int]facial t5sion1 4 4 4 4 4 #bb1 #fa ,ions1 cond5sation on1 4 4 4 4 4 #ec ,j ,jets ( liquid1 4 4 4 4 4 4 4 #ch ,l ,liquid cl\ds 9 liquid m$ia1 4 4 4 4 #ed columns1 4 4 4 4 4 4 #dj jets1 4 4 4 4 4 4 #ch ,liquids1 g5]al prop]ties (1 4 4 4 4 #b orig9 (1 4 4 4 4 4 4 #a prop]ties ( surface (1 4 4 4 #c ,m ,m9imum !rmomet]1 4 4 4 4 4 4 #f ,mi/s1 4 4 4 4 4 4 4 4 #di ,mono-brom-b5z5e1 4 4 4 4 4 4 #dh ,n ,network =m$ f film1 4 4 4 4 4 #gj ,nitrob5z5e1 drops (1 4 4 4 4 #bi1 #cg films1 4 4 4 4 4 4 #fi ,o ,or?otoluid9e columns1 4 4 4 4 4 #db drops1 4 4 4 4 4 4 #bg equi-d5sity temp]ature (1 4 4 4 #af globules1 movem5ts (1 4 4 4 4 #ff jets1 4 4 4 4 4 4 4 #ci sph]es1 4 4 4 4 4 #aa1 #ad ,p ,petroleum1 b\nd>y surface ) wat]1 4 4 4 #f ,plateau's sph]ule1 4 4 4 4 4 4 #be ,q ,qu9ol9e1 =mation ( globules (1 4 4 4 #fi r+s (1 4 4 4 4 4 4 #ga ,r ,ra9drops1 4 4 4 4 4 4 4 #ed ,s ,%ape ( deta*$ masses ( liquid1 4 4 4 #h ,silv] float+ on wat]1 4 4 4 4 4 #d ,solubility1 movem5ts due to1 4 4 4 4 #fc ,sph]es ( liquids1 effect ( temp]ature on1 4 #ae production (1 4 4 #aj ,sph]oidal /ate ( liquids1 4 4 4 4 #ei ,spread+ ( oil on wat]1 4 4 4 4 4 #fj ,surface sk9 ( wat]1 prop]ties (1 4 4 4 #c t5sion1 def9ition (1 4 4 4 4 #ba ph5om5a1 analogies to life1 4 #ge value = v>i\s liquids1 4 4 #bb ,w ,wat]1 column (1 4 4 4 4 4 4 #dj surface t5sion (1 4 4 4 4 #ba beetle1 4 4 4 4 4 4 #d ,x ,xylid9e #a-c-d1 movem5ts ( globules (1 4 4 #ff 7,pr #abff7 -------- ,butl] ,tann] ,frome & ,london ,transcription note ,! foll[+ m9or typographical flaws h be5 correct$3 - ,fig4 #g3 miss+ p]iod at ! end ( ! caption - feel]1' unnecess>y additional clos+ quote - 99,index399 ,drops ( liquid1 %apes (1 #aj1 #bi1 #cj1 #ca miss+ commas - 99,index399 ,mono-brom-b5z5e add$ hyph5 to con=m ) ref]5ce 9 text ,footnotes h be5 r5umb]$ progressively ?r\gh\t ! book4