,,! ,,/ory ,,( ,,g]m ,,life ,,by ,h4 ,w4 ,,conn ,,pr(essor ,,( ,,biology ,,at ,,wesleyan ,,univ]sity1 ,,au?or ,,( ,,evolution ,,( ,,to-,,day1 ,,! ,,liv+ ,,_w1 ,,etc4 ,,preface4 ,s9ce ! fir/ edition ( ?is book 0 publi%$ ! popul> idea ( bact]ia to :i* att5tion 0 drawn 9 ! orig9al preface has und]gone consid]able modification4 ,exp]im5tal m$ic9e has add$ con/antly to ! li/ ( diseases caus$ by bact]ial organisms1 & ! g5]al public has be5 educat$ to an adequate conception ( ! importance ( ! g]m z ! *ief ag5cy 9 ! transmission ( disease1 ) correspond+ advantage to ! effici5cy ( p]sonal & public hygi5e4 ,at ! same "t k ( ! b5ign bact]ia & ! enorm\s role !y play 9 ! indu/ries & ! arts has become mu* m widely diffus$4 ,bact]iology is be+ /udi$ 9 colleges z "o ( ! cultural sci5ces2 x is be+ widely adopt$ z a subject ( in/ruction 9 high s*ools2 & s*ools ( agriculture & h\sehold sci5ce turn out ea* ye> ?\s&s ( graduates famili> ) ! functions ( bact]ia 9 daily life4 ,?r\gh ^! ag5cies ! popul> misconception ( ! nature ( micro- organisms & _! relations to man is be+ gradually displac$ by a g5]al appreciation ( _! manifold s]vices4 ,x is n unreasonable to hope t ! _m ?\s&s ( copies ( ?is little manual :i* h be5 circulat$ & read h contribut$ mat]ially to t end4 ,if its popul>ity is a safe crit]ion1 ! book has amply fulfill$ its purpose ( plac+ be=e ! g5]al read] 9 a simple & direct /yle ! ma9 facts ( bact]iology4 ,beg9n+ ) a discussion ( ! nature ( bact]ia1 x %[s _! position 9 ! scale ( plant & animal life4 ,! middle *apt]s describe ! functions ( bact]ia 9 ! arts1 9 ! dairy1 & 9 agriculture4 ,! f9al *apt]s discuss ! relation ( bact]ia to disease & ! me?ods by :i* ! new & gr[+ sci5ce ( prev5tive m$ic9e combats & c\nt]acts _! dang]\s p[]s4 ,,july1 #aiae4 ,,cont5ts4 ,i4--,,bact]ia ,,z ,,plants ,hi/orical4--,=m ( bact]ia4--,multiplication ( bact]ia4--,spore =mation4--,motion4--,int]nal /ructure4--,animals or plants8-- ,classification4--,v>iation4--,:]e bact]ia are f\nd4 ,,ii4--,,miscellane\s ,,uses ,,( ,,bact]ia ,,9 ,,! ,,arts4 ,mac]ation indu/ries4--,l954--,jute4--,hemp4--,spon ges4--,lea!r4 --,f]m5tative indu/ries4--,v9eg>--,lactic acid4--,butyric acid4-- ,bact]ia 9 tobacco cur+4--,tr\blesome f]m5tations4 ,,iii4--,,bact]ia ,,9 ,,! ,,dairy4 ,s\rces ( bact]ia 9 milk4--,effect ( bact]ia on milk4-- ,bact]ia us$ 9 butt] mak+4--,bact]ia 9 *eese mak+4 ,,iv4--,,bact]ia ,,9 ,,natural ,,processes4 ,bact]ia z scav5g]s4--,bact]ia z ag5ts 9 ,nature's food cycle4--,relation ( bact]ia to agriculture4--,spr\t+ ( se$s4 --,! silo4--,! f]tility ( ! soil4--,bact]ia z s\rces ( tr\ble to ! f>m]4--,coal =mation4 ,v4--,,p>asitic ,,bact]ia ,,& ,,_! ,,relation ,,to ,,disease ,me?od ( produc+ disease4--,pa?og5ic g]ms n /rictly p>asitic4--,pa?og5ic g]ms t are true p>asites4--,:at diseases are due to bact]ia4--,v>iability ( pa?og5ic p[]s4-- ,susceptibility ( ! individual4--,recov]y f bact]iological diseases4--,diseases caus$ by organisms o!r ?an bact]ia4 ,,vi4--,,me?ods ,,( ,,combat+ ,,p>asitic ,,bact]ia ,prev5tive m$ic9e4--,bact]ia 9 surg]y4--,prev5tion by inoculation4--,limits ( prev5tive m$ic9e4--,curative m$ic9e4 --,drugs--,vis m$icatrix naturae4--,antitox9es & _! use4-- ,conclusion4 ,,! ,,/ory ,,( ,,g]m ,,life4 ,,*apt] ,i4 ,,bact]ia ,,z ,,plants4 ,dur+ ! la/ fifte5 ye>s ! subject ( bact]iology ,footnote3 ,! t]m microbe is simply a ^w :i* has be5 co9$ to include all ( ! microscopic plants commonly includ$ "u ! t]ms bact]ia & yea/s4 has develop$ ) a m>vell\s rapidity4 ,at ! beg9n+ ( ! n9? decade ( ! c5tury bact]ia 7 sc>cely he>d ( outside ( sci5tific circles1 & v little 0 kn[n ab\t !m ev5 among sci5ti/s4 ,today !y are almo/ h\sehold words1 & ev]yone :o reads is beg9n+ to recognise t !y h important relations to 8 ev]yday life4 ,! organisms call$ bact]ia comprise simply a small class ( l[ plants1 b ?is small gr\p has prov$ to be ( su* va/ importance 9 its relation to ! _w 9 g5]al t its /udy has little by little cry/alliz$ into a sci5ce by itself4 ,x is a some:at anomal\s fact t a special bran* ( sci5ce1 int]e/+ su* a l>ge numb] ( p1 %\ld be develop$ ar\nd a small gr\p ( l[ plants4 ,! importance ( bact]iology is n due to any importance bact]ia h z plants or z memb]s ( ! vegetable k+dom1 b solely to _! p[]s ( produc+ pr(\nd *anges 9 ,nature4 ,!re is no "o family ( plants t beg9s to comp>e ) !m 9 importance4 ,x is ! object ( ?is "w to po9t out briefly h[ mu* bo? ( good & ill we owe to ! life & gr[? ( ^! microscopic organisms4 ,z we h le>n$ m & m ( !m dur+ ! la/ fifty ye>s1 x has become m & m evid5t t ?is "o little class ( microscopic plants fills a place 9 ,nature's processes :i* 9 "s respects balances t fill$ by ! :ole ( ! gre5 plants4 ,m9ute z !y are1 _! importance c h>dly be ov]rat$1 = ^u _! activities is f\nd$ ! cont9u$ life ( ! animal & vegetable k+dom4 ,= good & = ill !y are ag5ts ( nev]ceas+ & almo/ unlimit$ p[]s4 ,,hi/orical4 ,! /udy ( bact]ia practically began ) ! use ( ! microscope4 ,x 0 t[>d ! close ( ! sev5te5? c5tury t ! ,dut* microscopi/1 ,leeuw5hoek1 work+ ) 8 simple l5ses1 fir/ saw ! organisms :i* we n[ "k "u ?is "n1 ) suffici5t cle>ness to describe !m4 ,beyond m5tion+ _! exi/5ce1 h[ev]1 8 obs]vations told little or no?+4 ,nor c mu* m be said ( ! /udies :i* foll[$ dur+ ! next "o hundr$ & fifty ye>s4 ,dur+ ?is long p]iod _m a microscope 0 turn$ to ! obs]vation ( ^! m9ute organisms1 b ! majority ( obs]v]s 7 cont5t$ ) simply see+ !m1 m>vell+ at _! m9ut5ess1 & utt]+ _m exclamations ( a/oni%m5t at ! wond]s ( ,nature4 ,a few m5 ( m /rictly sci5tific natures paid "s att5tion to ^! little organisms4 ,among !m we %\ld p]haps m5tion ,von ,glei*51 ,mull]1 ,spallanzani1 & ,ne$ham4 ,ea* ( ^!1 z well z o!rs1 made "s contributions to our k ( microscopical life1 & among o!r organisms /udi$ ^? :i* we n[ call bact]ia4 ,speculations 7 ev5 made at ^! e>ly dates ( ! possible causal connection ( ^! organisms ) diseases1 & = a little ! m$ical pr(ession 0 int]e/$ 9 ! sugge/ion4 ,x 0 impossible !n1 h[ev]1 to obta9 any evid5ce = ! tru? ( ?is speculation1 & x 0 ab&on$ z unf\nd$1 & ev5 =gott5 completely1 until reviv$ aga9 ab\t ! middle ( ! #ai? c5tury4 ,dur+ ?is c5tury ( wond] a suffici5cy ( exactness 01 h[ev]1 introduc$ into ! /udy ( microscopic organisms to call = ! use ( names1 & we f9d ,mull] us+ ! names ( ,monas1 ,proteus1 ,vibrio1 ,bacillus1 & ,spirillum1 names :i* /ill cont9ue 9 use1 al?\gh commonly ) a diff]5t significance f t giv5 !m by ,mull]4 ,mull] did inde$ make a /udy suffici5t to recognise ! sev]al di/9ct types1 & attempt$ to classsify ^! bodies4 ,!y 7 n reg>d$ z ( mu* importance1 b simply z ! mo/ m9ute organisms kn[n4 ,no?+ ( importance came f ?is "w1 h[ev]1 p>tly because ( ! inadequacy ( ! microscopes ( ! day1 & p>tly because ( a failure to und]/& ! real problems at issue4 ,:5 we rememb] ! m9ut5ess ( ! bact]ia1 ! impossibility ( /udy+ any "o ( !m = m ?an a few mom5ts at a "t --only s long1 9 fact1 z x c be foll[$ "u a microscope2 :5 we rememb]1 too1 ! imp]fection ( ! comp\nd microscopes :i* made high p[]s practical impossibilities2 &1 above all1 :5 we appreciate ! loos5ess ( ! ideas :i* p]vad$ all sci5ti/s z to ! necessity ( accurate obs]vation 9 di/9ction f inf]5ce1 x is n /range t ! la/ c5tury gave u no k ( bact]ia beyond ! m]e fact ( ! exi/5ce ( "s extremely m9ute organisms 9 diff]5t decay+ mat]ials4 ,nor did ! #ai? c5tury add mu* to ?is until t[>d its middle4 ,x is true t ! microscope 0 va/ly improv$ e>ly 9 ! c5tury1 & s9ce ?is improvem5t s]v$ z a decid$ /imulus to ! /udy ( microscopic life1 among o!r organisms /udi$1 bact]ia receiv$ "s att5tion4 ,ehr5b]g1 ,duj>d91 ,fu*s1 ,p]ty1 & o!rs left ! impress ( _! "w ^u bact]iology ev5 be=e ! middle ( ! c5tury4 ,x is true t ,s*wann %rewdly drew conclusions z to ! relation ( microscopic organisms to v>i\s processes ( f]m5tation & decay--conclusions :i*1 al?\gh n accept$ at ! "t1 h subsequ5tly prov$ to be correct4 ,x is true t ,fu*s made a c>eful /udy ( ! infection ( blue milk1 rea*+ ! correct conclusion t ! infection 0 caus$ by a microscopic organism :i* he discov]$ & c>efully /udi$4 ,x is true t ,h5le made a g5]al !ory z to ! relation ( su* organisms to diseases1 & po9t$ out ! logically necess>y /eps 9 a demon/ration ( ! causal connection betwe5 any organism & a disease4 ,x is true also t a g5]al !ory ( ! production ( ail k9ds ( f]m5tation by liv+ organisms _h be5 advanc$4 ,b all ^! sugge/ions made little impression4 ,on ! "o h&1 bact]ia 7 n recognis$ z a class ( organisms by !mselves--7 n1 inde$1 di/+ui%$ f yea/s or o!r m9ute animalcuise4 ,_! v>iety 0 n mi/ru/$ & _! significance n conceiv$4 ,z microscopic organisms1 !re 7 no reasons = consid]+ !m ( any m importance ?an any o!r small animals or plants1 & _! extreme m9ut5ess & simplicity made !m ( little int]e/ to ! microscopi/4 ,on ! o!r h&1 _! causal connection ) f]m5tative & putrefactive processes 0 entirely obscur$ by ! ov]%ad[+ weight ( ! *emi/ ,liebig1 :o believ$ t f]m5tations & putrefactions 7 simply *emical processes4 ,liebig insi/$ t all album9oid bodies 7 9 a /ate ( *emically un/able equilibrium1 & if left to !mselves w\ld fall to pieces )\t any ne$ ( ! action ( microscopic organisms4 ,! =ce ( ,liebig's au?ority & ! brilliancy ( 8 expositions l$ to ! wide acceptance ( 8 views & ! tempor>y obscurity ( ! relation ( microscopic organisms to f]m5tative & putrefactive processes4 ,! objections to ,liebig's views 7 h>dly notic$1 & ! =ce ( ! exp]im5ts ( ,s*wann 0 sil5tly ignor$4 ,until ! six? decade ( ! c5tury1 !re=e1 ^! organisms1 :i* h s9ce become ! basis ( a new bran* ( sci5ce1 _h h>dly em]g$ f obscurity4 ,a few microscopi/s recognis$ _! exi/5ce1 j z !y did any o!r gr\p ( small animals or plants1 b ev5 yet !y fail$ to look ^u !m z =m+ a di/9ct gr\p4 ,a gr[+ numb] ( obs]vations 0 accumulat+1 po9t+ t[>d a probable causal connection betwe5 f]m5tative & putrefactive processes & ! gr[? ( microscopic organisms2 b ^! obs]vations 7 kn[n only to a few1 & 7 ignor$ by ! majority ( sci5ti/s4 ,x 0 ,l\is ,pa/eur :o br\ght bact]ia to ! front1 & x 0 by 8 lab\rs t ^! organisms 7 rescu$ f ! obscurity ( sci5tific publications & made objects ( g5]al & cr[n+ int]e/4 ,x 0 ,pa/eur :o fir/ successfully combat$ ! *emical !ory ( f]m5tation by %[+ t album9\s matt] _h no inh]5t t5d5cy to decomposition4 ,x 0 ,pa/eur :o fir/ cle>ly demon/rat$ t ^! little bodies1 l all l>g] animals & plants1 come into exi/5ce only by ord9>y me?ods ( reproduction1 & n by any spontane\s g5]ation1 z _h be5 e>li] claim$4 ,x 0 ,pa/eur :o fir/ prov$ t su* a common ph5om5on z4 ! s\r+ ( milk 0 produc$ by microscopic organisms gr[+ 9 ! milk4 ,x 0 ,pa/eur :o fir/ succe$$ 9 demon/rat+ t c]ta9 species ( microscopic organisms are ! cause ( c]ta9 diseases1 & 9 sugge/+ successful me?ods ( avoid+ !m4 ,all ^! discov]ies 7 made 9 rapid succession4 ,)9 t5 ye>s ( ! "t t 8 "n began to be he>d 9 ?is connection by sci5ti/s1 ! subject _h advanc$ s rapidly t x _h become evid5t t "h 0 a new subject ( importance to ! sci5tific _w1 if n to ! public at l>ge4 ,! o!r important discov]ies :i* ,pa/eur made x is n our purpose to m5tion "h4 ,8 claim to be consid]$ ! f\nd] ( bact]iology w be recognis$ f :at has already be5 m5tion$4 ,x 0 n t he fir/ discov]$ ! organisms1 or fir/ /udi$ !m2 x 0 n t he fir/ sugge/$ _! causal connection ) f]m5tation & disease1 b x 0 because he = ! fir/ "t plac$ ! subject ^u a firm f\ndation by prov+ ) rigid exp]im5t "s ( ! sugge/ions made by o!rs1 & 9 ?is way turn$ ! att5tion ( sci5ce to ! /udy ( micro-organisms4 ,aft] ! importance ( ! subject _h be5 demon/rat$ by ,pa/eur1 o!rs turn$ _! att5tion 9 ! same direction1 ei!r = ! purpose ( v]ification or refutation ( ,pa/eur's views4 ,! advance 0 n v rapid1 h[ev]1 s9ce bact]iological exp]im5tation prov$ to be a subject ( extraord9>y difficulty4 ,bact]ia 7 n ev5 yet recognis$ z a gr\p ( organisms di/9ct en\gh to be gr\p$ by !mselves1 b 7 ev5 by ,pa/eur at fir/ conf\nd$ ) yea/s4 ,z a di/9ct gr\p ( organisms !y 7 fir/ di/+ui%$ by ,h(fman 9 #ahfi1 s9ce :i* date ! t]m bact]ia1 z apply+ to ?is special gr\p ( organisms1 has be5 com+ m & m into use4 ,s difficult 7 ! inve/igations1 t = ye>s !re 7 h>dly any inve/igators besides ,pa/eur :o c\ld successfully h&le ! subject & rea* conclusions :i* c\ld /& ! te/ ( "t4 ,= ! next ?irty ye>s1 al?\gh inve/igators & inve/igations cont9u$ to increase1 we c f9d little besides dispute & confusion along ?is l9e4 ,! difficulty ( obta9+ = exp]im5t any "o k9d ( bact]ia by itself1 unmix$ ) o!rs 7pure cultures71 r5d]$ advance almo/ impossible4 ,s conflict+ 7 ! results t ! :ole subject soon came into almo/ hopeless confusion1 & v few /eps 7 tak5 ^u any sure basis4 ,s difficult 7 ! me?ods1 s contradictory & confus+ ! results1 because ( impure cultures1 t a /ud5t ( to-day :o wi%es to look up ! previ\s discov]ies 9 almo/ any l9e ( bact]iology ne$ h>dly g back ( #ahhj1 s9ce he c almo/ re/ assur$ t any?+ done e>li] ?an t 0 m likely to be errone\s ?an correct4 ,! la/ fifte5 ye>s h1 h[ev]1 se5 a wond]ful *ange4 ,! difficulties _h be5 mo/ly ^? ( me?ods ( "w1 & ) ! n9? decade ( ! c5tury ^! me?ods 7 simplifi$ by ,rob]t ,ko*4 ,?is simplification ( me?od = ! fir/ "t plac$ ?is l9e ( inve/igation )9 ! rea* ( sci5ti/s :o did n h ! g5ius ( ,pa/eur4 ,x 0 n[ possible to get pure cultures easily1 & to obta9 ) su* pure cultures results :i* 7 uni=m & simple4 ,x 0 n[ possible to take /eps :i* _h ! /amp ( accuracy ^u !m1 & :i* fur!r exp]im5t did n disprove4 ,f ! "t :5 ^! me?ods 7 ?us made manageable ! /udy ( bact]ia increas$ ) a rapidity :i* has be5 fairly />tl+1 & ! in=mation :i* has accumulat$ is almo/ =midable4 ,! v rapidity ) :i* ! inve/igations h progress$ has br\ght consid]able confusion1 f ! fact t ! new discov]ies h n _h "t to be prop]ly assimilat$ into k4 ,today _m facts are kn[n ^: significance is /ill unc]ta91 & a cle> logical discussion ( ! facts ( mod]n bact]iology is n possible4 ,b suffici5t k has be5 accumulat$ & dige/$ to %[ u at lea/ ! direction along :i* bact]iological advance is t5d+1 & x is to ! po9t+ out ( ^! directions t ! foll[+ pages w be devot$4 ,,:at ,,are ,,bact]ia8 ,! mo/ int]e/+ facts connect$ ) ! subject ( bact]iology conc]n ! p[]s & influ5ce 9 ,nature possess$ by ! bact]ia4 ,! morphological side ( ! subject is int]e/+ en\gh to ! sci5ti/1 b to him alone4 ,/ill1 x is impossible to attempt to /udy ! p[]s ( bact]ia )\t kn[+ some?+ ( ! organisms !mselves4 ,to und]/& h[ !y come to play an important "p 9 ,nature's processes1 we mu/ "k fir/ h[ !y look & :]e !y are f\nd4 ,a %ort consid]ation ( c]ta9 morphological facts w !re=e be necess>y at ! />t4 ,,=m ,,( ,,bact]ia4 ,9 %ape bact]ia are ! simple/ conceivable /ructures4 ,al?\gh !re are hundr$s ( diff]5t species1 !y h only ?ree g5]al =ms1 :i* h be5 aptly comp>$ to billi>d balls1 lead p5cils1 & corkscrews4 ,sph]es1 rods1 & spirals repres5t all %apes4 ,! sph]es may be l>ge or small1 & may gr\p !mselves 9 v>i\s ways2 ! rods may be long or %ort1 ?ick or sl5d]2 ! spirals may be loosely or tightly coil$1 & may h only "o or two or may h _m coils1 & !y may be flexible or /iff2 b /ill rods1 sph]es1 & spirals comprise all types4 ,9 size !re is "s v>iation1 ?\gh n v great4 ,all are extremely m9ute1 & nev] visible to ! nak$ eye4 ,! sph]es v>y f #j4be u to #a4e u 7#j4jjjjab to #j4jjjjf in*es74 ,! rods may be no m ?an #j4c u 9 diamet]1 or may be z wide z #a4e u to #b4e u1 & 9 l5g? v>y all ! way f a l5g? sc>cely long] ?an _! diamet] to long ?reads4 ,ab\t ! same may be said ( ! spiral =ms4 ,!y are decid$ly ! smalle/ liv+ organisms :i* our microscopes h reveal$4 ,9 _! me?od ( gr[? we f9d "o ( ! mo/ *>act]i/ic features4 ,!y univ]sally h ! p[] ( multiplication by simple division or fission4 ,ea* individual elongates & !n divides 9 ! middle into two simil> halves1 ea* ( :i* !n repeats ! process4 ,?is me?od ( multiplication by simple division is ! di/+ui%+ m>k :i* sep>ates ! bact]ia f ! yea/s1 ! latt] plants multiply+ by a process kn[n z budd+4 ,fig4 #b %[s ^! two me?ods ( multiplication4 ,:ile all bact]ia ?us multiply by division1 c]ta9 diff]5ces 9 ! details produce r /rik+ diff]5ces 9 ! results4 ,consid]+ fir/ ! sph]ical =ms1 we f9d t "s species divide1 z describ$1 into two1 :i* sep>ate at once1 & ea* ( :i* 9 turn divides 9 ! opposite direction1 call$ ,micrococcus1 7,fig4 #c74 ,o!r species divide only 9 "o direction4 ,frequ5tly !y d n sep>ate aft] divid+1 b rema9 atta*$4 ,ea*1 h[ev]1 aga9 elongates & divides aga91 b all /ill rema9 atta*$4 ,!re are ?us =m$ long *a9s ( sph]es l /r+s ( beads1 call$ ,/reptococci 7,fig4 #d74 ,o!r species divide fir/ 9 "o direction1 !n at "r angles to ! fir/ division1 & a ?ird division foll[s at "r angles to ! plane ( ! fir/ two1 ?us produc+ solid gr\ps ( f\rs1 eights1 or sixte5s 7,fig #e71 call$ ,s>c9a4 ,ea* diff]5t species ( bact]ia is uni=m 9 its me?od ( division1 & ^! diff]5ces are !re=e indications ( diff]5ces 9 species1 or1 accord+ to our pres5t me?od ( classification1 ! diff]5t me?ods ( division repres5t diff]5t g5]a4 ,all bact]ia produc+ ,/reptococcus *a9s =m a s+le g5us ,/reptococcus1 & all :i* divide 9 ?ree division planes =m ano!r g5us1 ,s>c9a1 etc4 ,! rod-%ap$ bact]ia also diff] some:at1 b to a less ext5t4 ,!y almo/ always divide 9 a plane at "r angles to _! longe/ dim5sion4 ,b "h aga9 we f9d "s species sep>at+ imm$iately aft] division1 & ?us always appe>+ z %ort rods 7,fig4 #f71 :ile o!rs rema9 atta*$ aft] division & =m long *a9s4 ,sometimes !y appe> to cont9ue to increase 9 l5g? )\t %[+ any signs ( division1 & 9 ?is way long ?reads are =m$ 7,fig4 #g74 ,^! ?reads are1 h[ev]1 pot5tially at lea/1 long *a9s ( %ort rods1 & "u prop] conditions !y w break up into su* %ort rods1 z %[n 9 ,fig4 #g;a4 ,occasionally a rod species may divide l5g?wise1 b ?is is r>e4 ,exactly ! same may be said ( ! spiral =ms4 ,"h1 too1 we f9d %ort rods & long *a9s1 or long spiral filam5ts 9 :i* c be se5 no division into %ort] elem5ts1 b :i*1 "u c]ta9 conditions1 break up into %ort sections4 ,,rapidity ,,( ,,multiplication4 ,x is ?is p[] ( multiplication by division t makes bact]ia ag5ts ( su* significance4 ,_! m9ute size w\ld make !m h>mless en\gh if x 7 n = an extraord9>y p[] ( multiplication4 ,?is p[] ( gr[? & division is almo/ incr$ible4 ,"s ( ! species :i* h be5 c>efully wat*$ "u ! microscope h be5 f\nd "u fav\rable conditions to gr[ s rapidly z to divide e half h\r1 or ev5 less4 ,! numb] ( (fspr+ t w\ld result 9 ! c\rse ( tw5ty-f\r h\rs at ?is rate is ( c\rse easily comput$4 ,9 "o day ea* bact]ium w\ld produce ov] #af1ejj1jjj desc5dants1 & 9 two days ab\t #bha1ejj1jjj1jjj4 ,x has be5 fur!r calculat$ t ^! #bha1ejj1jjj1jjj w\ld =m ab\t a solid p9t ( bact]ia & weigh ab\t a p\nd4 ,at ! end ( ! ?ird day ! total desc5dants w\ld am\nt to #dg1jjj1jjj1jjj1jjj1 & w\ld weigh ab\t #af1jjj1jjj p\nds4 ,( c\rse ^! numb]s h no significance1 = !y are nev] actual or ev5 possible numb]s4 ,long be=e ! (fspr+ rea* ev5 into ! millions _! rate ( multiplication is *eck$ ei!r by lack ( food or by ! accumulation ( _! own excret$ products1 :i* are injuri\s to !m4 ,b ! figures d h int]e/ s9ce !y %[ fa9tly :at an unlimit$ p[] ( multiplication ^! organisms h1 & ?us %[ u t 9 deal+ ) bact]ia we are deal+ ) =ces ( almo/ inf9ite ext5t4 ,?is wond]ful p[] ( gr[? is *iefly due to ! fact t bact]ia fe$ ^u food :i* is highly organiz$ & already 9 condition = absorption4 ,mo/ plants mu/ manufacture _! own foods out ( simpl] sub/ances1 l c>bonic dioxide 7,co#b7 & wat]1 b bact]ia1 z a rule1 fe$ ^u complex organic mat]ial already prep>$ by ! previ\s life ( plants or animals4 ,= ?is reason !y c gr[ fa/] ?an o!r plants4 ,n be+ oblig$ to make _! own foods l mo/ plants1 nor to se>* = x l animals1 b liv+ 9 its mid/1 _! rapidity ( gr[? & multiplication is limit$ only by _! p[] to seize & assimilate ?is food4 ,z !y gr[ 9 su* masses ( food1 !y cause c]ta9 *emical *anges to take place 9 x1 *anges d\btless directly connect$ ) _! use ( ! mat]ial z food4 ,recognis+ t !y d cause *emical *anges 9 food mat]ial1 & rememb]+ ?is m>vell\s p[] ( gr[?1 we are prep>$ to believe !m capable ( produc+ *anges :]ev] !y get a foo?old & beg9 to gr[4 ,_! p[] ( fe$+ ^u complex organic food & produc+ *emical *anges !re91 toge!r ) _! m>vell\s p[] ( assimilat+ ?is mat]ial z food1 make !m ag5ts 9 ,nature ( extreme importance4 ,,diff]5ces ,,betwe5 ,,diff]5t ,,species ,,( ,,bact]ia4 ,:ile bact]ia are ?us v simple 9 =m1 !re are a few o!r slight v>iations 9 detail :i* assi/ 9 di/+ui%+ !m4 ,! rods are sometimes v blunt at ! ends1 almo/ z if cut squ>e across1 :ile 9 o!r species !y are m r\nd$ & occasionally slightly tap]+4 ,sometimes !y are surr\nd$ by a ?9 lay] ( "s gelat9\s sub/ance1 :i* =ms :at is call$ a capsule 7,fig4 #aj74 ,?is capsule may connect !m & s]ve z a cem5t1 to prev5t ! sep>ate elem5ts ( a *a9 f fall+ ap>t4 ,sometimes su* a gelat9\s secretion w unite great masses ( bact]ia into clu/]s1 :i* may float on ! surface ( ! liquid 9 :i* !y gr[ or may s9k to ! bottom4 ,su* masses are call$ zoogloea1 & _! g5]al appe>ance s]ves z "o ( ! *>act]s = di/+ui%+ diff]5t species ( bact]ia 7,fig4 #aj1 a & b74 ,:5 gr[+ 9 solid m$ia1 su* z a nutriti\s liquid made /iff ) gelat9e1 ! diff]5t species h diff]5t me?ods ( spread+ f _! c5tral po9t ( orig94 ,a s+le bact]ium 9 ! mid/ ( su* a /iff5$ mass w fe$ ^u x & produce desc5dants rapidly2 b ^! desc5dants1 n be+ able to move ?r\gh ! gelat9e1 w rema9 clu/]$ toge!r 9 a mass1 :i* ! bact]iologi/ calls a colony4 ,b _! me?od ( clu/]+1 due to diff]5t me?ods ( gr[?1 is by no means always alike1 & ^! colonies %[ great diff]5ces 9 g5]al appe>ance4 ,! diff]5ces appe> to be con/ant1 h[ev]1 = ! same species ( bact]ia1 & h5ce ! %ape & appe>ance ( ! colony enable bact]iologi/s to disc]n diff]5t species 7,fig4 ,,ii74 ,all ^! po9ts ( diff]5ce are ( practical use to ! bact]iologi/ 9 di/+ui%+ species4 ,,spore ,,=mation4 ,9 addition to _! p[] ( reproduction by simple division1 _m species ( bact]ia h a second me?od by means ( spores4 ,spores are special r\nd$ or oval bits ( bact]ia protoplasm capable ( resi/+ adv]se conditions :i* w\ld de/roy ! ord9>y bact]ia4 ,!y arise among bact]ia 9 two diff]5t me?ods4 ,endog5\s spores4--,^! spores arise inside ( ! rods or ! spiral =ms 7,fig4 #ab74 ,!y fir/ appe> z slight granul> masses1 or z d>k po9ts :i* become gradually di/9ct f ! re/ ( ! rod4 ,ev5tually !re is ?us =m$ inside ! rod a cle>1 highly refractive1 sph]ical or oval spore1 :i* may ev5 be ( a great] diamet] ?an ! rod produc+ x1 ?us caus+ x to swell out & become sp9dle =m$ ,fig4 #ab c4 ,^! spores may =m 9 ! middle or at ! ends ( ! rods 7,fig4 #ab74 ,!y may use up all ! protoplasm ( ! rod 9 _! =mation1 or !y may use only a small "p ( x1 ! rod :i* =ms !m cont9u+ its activities 9 spite ( ! =mation ( ! spores )9 x4 ,!y are always cle> & highly refractive f conta9+ little wat]1 & !y d n s readily absorb /a9+ mat]ial z ! ord9>y rods4 ,!y appe> to be cov]$ ) a lay] ( "s sub/ance :i* resi/s ! /a91 & :i* also enables !m to resi/ v>i\s ext]nal ag5cies4 ,?is protective cov]+1 toge!r ) _! small am\nt ( wat]1 enables !m to resi/ almo/ any am\nt ( dry+1 a high degree ( heat1 & _m o!r adv]se conditions4 ,commonly ! spores break out ( ! rod1 & ! rod produc+ !m dies1 al?\gh sometimes ! rod may cont9ue its activity ev5 aft] ! spores h be5 produc$4 ,ar?rog5\s spores 7874--,c]ta9 species ( bact]ia d n produce spores z j describ$1 b may give rise to bodies t are sometimes call$ ar?rospores4 ,^! bodies are =m$ z %ort segm5ts ( rods4 ,a long rod may sometimes break up into sev]al %ort r\nd$ elem5ts1 :i* are cle> & appe> to h a some:at increas$ p[] ( resi/+ adv]se conditions4 ,! same may happ5 among ! sph]ical =ms1 :i* only 9 r>e in/ances =m endog5\s spores4 ,among ! sph]es :i* =m a *a9 ( /reptococci "s may occasionally be slightly diff]5t f ! re/4 ,!y are a little l>g]1 & h be5 ?\ght to h an increas$ resi/+ p[] l t ( true spores 7,fig4 #ac b74 ,x is q d\btful1 h[ev]1 :e!r x is prop] to reg>d ^! bodies z spores4 ,!re is no good evid5ce t !y h any special resi/+ p[] to heat l endog5\s spores1 & bact]iologi/s 9 g5]al are incl9$ to reg>d !m simply z re/+ cells4 ,! t]m ar?rospores has be5 giv5 to !m to indicate t !y are =m$ z jo9ts or segm5ts1 & ?is t]m may be a conv5i5t "o to reta9 al?\gh ! bodies 9 "q are n true spores4 ,/ill a diff]5t me?od ( spore =mation occurs 9 a few peculi> bact]ia4 ,9 ?is case 7,fig4 #ad7 ! protoplasm 9 ! l>ge ?read breaks into _m m9ute sph]ical bodies1 :i* f9ally f9d exit4 ,! spores ?us =m$ may n be all alike1 diff]5ces 9 size be+ notic$4 ,?is me?od ( spore =mation occurs only 9 a few special =ms ( bact]ia4 ,! matt] ( spore =mation s]ves z "o ( ! po9ts = di/+ui%+ species4 ,"s species d n =m spores1 at lea/ "u any ( ! conditions 9 :i* !y h be5 /udi$4 ,o!rs =m !m readily 9 almo/ any condition1 & o!rs aga9 only "u special conditions :i* are adv]se to _! life4 ,! me?od ( spore =mation is always uni=m = any s+le species4 ,:atev] be ! me?od ( ! =mation ( ! spore1 its purpose 9 ! life ( ! bact]ium is always ! same4 ,x s]ves z a means ( keep+ ! species alive "u conditions ( adv]sity4 ,its p[] ( resi/+ heat or dry+ enables x to live :]e ! ord9>y active =ms w\ld be spe$ily kill$4 ,"s ( ^! spores are capable ( resi/+ a heat ( #ahj degrees ,c4 7#cfj degrees ,f47 = a %ort "t1 & boil+ wat] !y c resi/ = a long "t4 ,su* spores :5 subsequ5tly plac$ "u fav\rable conditions w g]m9ate & />t bact]ial activity anew4 ,,motion4 ,"s species ( bact]ia h ! p[] ( active motion1 & may be se5 d>t+ rapidly to & fro 9 ! liquid 9 :i* !y are gr[+4 ,?is motion is produc$ by flagella :i* protrude f ! body4 ,^! flagella 7,fig4 #ae7 arise f a membrane surr\nd+ ! bact]ium1 b h an intimate connection ) ! protoplasmic cont5t4 ,_! di/ribution is diff]5t 9 diff]5t species ( bact]ia4 ,"s species h a s+le flagellum at "o end 7,fig4 #ae a74 ,o!rs h "o at ea* end 7,fig4 #ae b74 ,o!rs1 aga91 h1 at lea/ j be=e divid+1 a bun* at "o or bo? ends 7,fig4 #ae c & d71 :ile o!rs1 aga91 h _m flagella di/ribut$ all ov] ! body 9 d5se pr(usion 7,fig4 #ae e74 ,^! flagella keep up a la%+ to & fro 9 ! liquid1 & ! la%+ s]ves to propel ! bact]ia ?r\gh ! liquid4 ,,int]nal ,,/ructure4 ,x is h>dly possible to say mu* ab\t ! /ructure ( ! bact]ia beyond ! description ( _! ext]nal =ms4 ,) all ! v>iations 9 detail m5tion$1 !y are extraord9>ily simple1 & ab\t all t c be se5 is _! ext]nal %ape4 ,( c\rse1 !y h "s int]nal /ructure1 b we "k v little 9 reg>d to x4 ,"s microscopi/s h describ$ c]ta9 appe>ances :i* !y ?9k indicate int]nal /ructure4 ,fig4 #af %[s "s ( ^! appe>ances4 ,! matt] is z yet v obscure1 h[ev]4 ,! bact]ia appe> to h a membran\s cov]+ :i* sometimes is ( a cellulose nature4 ,)9 x is protoplasm :i* %[s v>i\s unc]ta9 appe>ances4 ,"s microscopi/s h ?\ght !y c\ld f9d a nucleus1 & h reg>d$ bact]ia z cells ) inclos$ nucleii 7,figs4 #aj a & #ae f74 ,o!rs h reg>d$ ! :ole bact]ium z a nucleus )\t any protoplasm1 :ile o!rs1 aga91 h conclud$ t ! disc]n$ int]nal /ructure is no?+ except an appe>ance pres5t$ by ! physical arrangem5t ( ! protoplasm4 ,:ile we may believe t !y h "s int]nal /ructure1 we mu/ recognise t z yet microscopi/s h n be5 able to make x out4 ,9 %ort1 ! bact]ia aft] two c5turies ( /udy appe> to u ab\t z !y did at fir/4 ,!y mu/ /ill be describ$ z m9ute sph]es1 rods1 or spirals1 ) no fur!r disc]nible /ructure1 sometimes motile & sometimes /ation>y1 sometimes produc+ spores & sometimes n1 & multiply+ univ]sally by b9>y fission4 ,) all ! developm5t ( ! mod]n microscope we c h>dly say m ?an ?is4 ,our advance 9 k ( bact]ia is connect$ almo/ :olly ) _! me?ods ( gr[? & ! effects !y produce 9 ,nature4 ,,animals ,,or ,,plants8 ,!re has be5 9 ! pa/ n a little "q z to :e!r bact]ia %\ld be rightly class$ ) plants or ) animals4 ,!y c]ta9ly h *>act]s :i* ally !m ) bo?4 ,_! v common p[] ( active indep5d5t motion & _! common habit ( liv+ ^u complex bodies = foods are animal *>act]s1 & h l5t =ce to ! sugge/ion t !y are true animals4 ,b _! g5]al =m1 _! me?od ( gr[? & =mation ( ?reads1 & _! me?od ( spore =mation are q plantlike4 ,_! g5]al =m is v simil> to a gr\p ( l[ gre5 plants kn[n z ,oscill>ia4 ,fig4 #ag %[s a gr\p ( ^! ,oscill>iae1 & ! simil>ity ( ?is to "s ( ! ?read-l bact]ia is decid$4 ,! ,oscill>iae are1 h[ev]1 true plants1 & are ( a gre5 col\r4 ,bact]ia are !re=e to- day look$ ^u z a l[ type ( plant :i* has no *lorophyll1 ,footnote3 ,*lorophyll is ! gre5 col\r+ matt] ( plants4 b is relat$ to ,oscill>iae4 ,! abs5ce ( ! *lorophyll has =c$ !m to adopt new relations to food1 & compels !m to fe$ ^u complex foods in/ead ( ! simple ones1 :i* =m ! food ( gre5 plants4 ,we may h no hesitation1 !n1 9 call+ !m plants4 ,x is int]e/+ to notice t ) ?is idea _! place 9 ! organic _w is r$uc$ to a small "o sy/ematically4 ,!y d n =m a class by !mselves1 b are simply a subclass1 or ev5 a family1 & a family closely relat$ to sev]al o!r common plants4 ,b ! abs5ce ( *lorophyll & ! result+ peculi> life has br\ght ab\t a curi\s anomaly4 ,:]eas _! close/ allies are kn[n only to botani/s1 & are ( no int]e/ outside ( _! sy/ematic relations1 ! bact]ia are famili> to e "o1 & are dem&+ ! life att5tion ( hundr$s ( inve/igators4 ,x is _! abs5ce ( *lorophyll & _! consequ5t dep5d5ce ^u complex foods :i* has produc$ ?is anomaly4 ,,classification ,,( ,,bact]ia4 ,:ile x has g5]ally be5 recognis$ t bact]ia are plants1 any fur!r classification has prov$ a matt] ( great difficulty1 & bact]iologi/s f9d x extremely difficult to devise means ( di/+ui%+ species4 ,_! extreme simplicity makes x no easy matt] to f9d po9ts by :i* any species c be recognis$4 ,b 9 spite ( _! simil>ity1 !re is no d\bt t _m diff]5t species exi/4 ,bact]ia :i* appe> to be almo/ id5tical1 "u ! microscope prove to h entirely diff]5t prop]ties1 & mu/ !re=e be reg>d$ z di/9ct species4 ,b h[ to di/+ui% !m has be5 a puzzle4 ,microscopi/s h come to look ^u ! diff]5ces 9 %ape1 multiplication1 & =mation ( spores z furni%+ data suffici5t to enable !m to divide ! bact]ia into g5]a4 ,! g5us ,bacillus1 = in/ance1 is ! "n giv5 to all rod-%ap$ bact]ia :i* =m endog5\s spores1 etc4 ,b to di/+ui% small] subdivisions x has be5 f\nd necess>y to fall back ^u o!r *>act]s1 su* z ! %ape ( ! colony produc$ 9 solid gelat9e1 ! p[] to produce disease1 or to oxidize nitrites1 etc4 ,?us at pres5t ! diff]5t species are di/+ui%$ r by _! physiological ?an _! morphological *>act]s4 ,?is is an unsatisfactory basis ( classification1 & has produc$ mu* confusion 9 ! attempts to classify bact]ia4 ,! problem ( det]m9+ ! species ( bact]ia is to-day a v difficult "o1 & ) our be/ me?ods is /ill unsatisfactorily solv$4 ,a few species ( m>k$ "* are well kn[n1 & _! p[]s ( action s well und]/ood t !y c be readily recognis$2 b ( ! great ho/ ( bact]ia /udi$1 ! l>ge majority h be5 s slightly exp]im5t$ ^u t _! *>act]s are n kn[n1 & x is impossible1 !re=e1 to di/+ui% _m ( !m ap>t4 ,we f9d t ea* bact]iologi/ work+ 9 any special l9e commonly keeps a li/ ( ! bact]ia :i* he f9ds1 ) su* data 9 reg>d to !m z he has collect$4 ,su* a li/ is ( value to him1 b commonly ( little value to o!r bact]iologi/s f ! insuffici5cy ( ! data4 ,?us x happ5s t a l>ge "p ( ! diff]5t species ( bact]ia describ$ 9 lit]ature to- day h be5 f\nd & /udi$ by "o inve/igator alone4 ,by him !y h be5 describ$ & p]haps nam$4 ,q likely ! same species may h be5 f\nd by two or ?ree o!r bact]iologi/s1 b ow+ to ! difficulty ( comp>+ results & ! incomplet5ess ( ! descriptions ! id5tity ( ! species is n discov]$1 & !y are probably describ$ aga9 "u diff]5t names4 ,! same process may be repeat$ ov] & ov] aga91 until ! same species ( bact]ium w come to be kn[n by sev]al diff]5t names1 z x has be5 /udi$ by diff]5t obs]v]s4 ,,v>iation ,,( ,,bact]ia4 ,?is matt] is made ev5 m confus+ by ! fact t any species ( bact]ium may %[ m or less v>iation4 ,at "o "t 9 ! hi/ory ( bact]iology1 a p]iod la/+ = _m ye>s1 x 0 ! preval5t op9ion t !re 0 no con/ancy among bact]ia1 b t ! same species might assume almo/ any ( ! v>i\s =ms & %apes1 & possess v>i\s prop]ties4 ,bact]ia 7 reg>d$ by "s z /ages 9 ! life hi/ory ( high] plants4 ,?is "q z to :e!r bact]ia rema9 con/ant 9 "* = any consid]able l5g? ( "t has ev] be5 a prom95t "o ) bact]iologi/s1 & ev5 to-day we h>dly "k :at ! f9al answ] w be4 ,x has be5 demon/rat$ beyond p]adv5ture t "s species may *ange _! physiological *>act]s4 ,disease bact]ia1 = in/ance1 "u c]ta9 conditions lose _! p[]s ( develop+ disease4 ,species :i* s\r milk1 or o!rs :i* turn gelat9e gre51 may lose _! *>act]s4 ,n[1 s9ce x is ^u j su* physiological *>act]s z ^! t we mu/ dep5d 9 ord] to sep>ate diff]5t species ( bact]ia f ea* o!r1 x w be se5 t great confusion & unc]ta9ty w result 9 our attempts to def9e species4 ,fur!r1 x has be5 prov$ t !re is sometimes m or less ( a metamorphosis 9 ! life hi/ory ( c]ta9 species ( bact]ia4 ,! same species may =m a %ort rod1 or a long ?read1 or break up into sph]ical spores1 & ?us ei!r a %ort rod1 or a ?read1 or a sph]ical =m may belong to ! same species4 ,o!r species may be motile at "o "t & /ation>y at ano!r1 :ile at a ?ird p]iod x is a simple mass ( sph]ical spores4 ,a sph]ical =m1 :5 x l5g!ns be=e divid+1 appe>s z a %ort rod1 & a %ort rod =m aft] divid+ may be s %ort z to appe> l a sph]ical organism4 ,) all ^! reasons = confusion1 x is n to be wond]$ at t no satisfactory classification ( bact]ia has be5 rea*$1 or t diff]5t bact]iologi/s d n agree z to :at con/itutes a species1 or :e!r two =ms are id5tical or n4 ,b ) all ! confusion !re is sl[ly be+ obta9$ some?+ l sy/em4 ,9 spite ( ! fact t species may v>y & %[ diff]5t prop]ties "u diff]5t conditions1 ! fundam5tal con/ancy ( species is ev]y:]e recognis$ to-day z a fact4 ,! memb]s ( ! same species may %[ diff]5t prop]ties "u diff]5t conditions1 b x is believ$ t "u id5tical conditions ! prop]ties w be con/ant4 ,x is no m possible to conv]t "o species into ano!r ?an x is among ! high] ord]s ( plants4 ,x is believ$ t bact]ia d =m a gr\p ( plants by !mselves1 & are n to be reg>d$ z /ages 9 ! hi/ory ( high] plants4 ,x is believ$ t1 toge!r ) a consid]able am\nt ( v>iability & an occasional some:at long life hi/ory ) successive /ages1 !re is also an ess5tial con/ancy4 ,a sy/ematic classification has be5 made :i* is becom+ m or less satisfactory4 ,we are con/antly le>n+ m & m ( ! *>act]s1 s t !y c be recognis$ 9 diff]5t places by diff]5t obs]v]s4 ,x is ! conviction ( all :o "w ) bact]ia t1 9 spite ( ! difficulties1 x is only a matt] ( "t :5 we %all h a classification & description ( bact]ia s complete z to *>act]ize ! diff]5t species accurately4 ,ev5 ) our pres5t incomplete k ( :at *>act]izes a species1 x is necess>y to use "s names4 ,bact]ia are commonly giv5 a g5]ic "n bas$ ^u _! microscopic appe>ance4 ,!re are only a few ( ^! names4 ,micrococcus1 ,/reptococcus1 ,/aphylococcus1 ,s>c9a1 ,bact]ium1 ,bacillus1 ,spirillum1 are all ! names 9 common use apply+ to ! ord9>y bact]ia4 ,!re are a few o!rs less commonly us$4 ,to ?is g5]ic "n a specific "n is commonly add$1 bas$ ^u "s physiological "*4 ,= example1 ,bacillus typhosus is ! "n giv5 to ! bacillus :i* causes typhoid fev]4 ,su* names are ( great use :5 ! species is a common & well-kn[n "o1 b ( d\btful value = less-kn[n species ,x frequ5tly happ5s t a bact]iologi/ makes a /udy ( ! bact]ia f\nd 9 a c]ta9 locality1 & obta9s ?us a long li/ ( species hi!rto unkn[n4 ,9 ^! cases x is common simply to numb] ^! species r ?an "n !m4 ,?is me?od is frequ5tly advisable1 s9ce ! bact]iologi/ c seldom hunt up all bact]iological lit]ature ) suffici5t accuracy to det]m9e :e!r "s o!r bact]iologi/ may n h f\nd ! same species 9 an entirely diff]5t locality4 ,"o bact]iologi/1 = example1 f9ds "s sev5ty diff]5t species ( bact]ia 9 diff]5t *eeses4 ,he /udies !m en\gh = 8 own purposes1 b n suffici5tly to det]m9e :e!r "s o!r p]son may n h f\nd ! same species p]haps 9 milk or wat]4 ,he !re=e simply numb]s !m--a me?od :i* conveys no sugge/ion z to :e!r !y may be new species or n4 ,?is me?od avoids ! giv+ ( sep>ate names to ! same species f\nd by diff]5t obs]v]s1 & x is hop$ t gradually accumulat+ k w 9 "t gr\p toge!r ! =ms :i* are really id5tical1 b :i* h be5 describ$ by diff]5t obs]v]s4 ,,:]e ,,bact]ia ,,are ,,f\nd4 ,!re are no o!r plants or animals s univ]sally f\nd 9 ,nature z ! bact]ia4 ,x is ?is univ]sal pres5ce1 toge!r ) _! great p[]s ( multiplication1 :i* r5d]s !m ( s mu* importance 9 ,nature4 ,!y exi/ almo/ ev]y:]e on ! surface ( ! e>?4 ,!y are 9 ! soil1 especially at its surface4 ,!y d n ext5d to v great dep?s ( soil1 h[ev]1 few exi/+ bel[ f\r feet ( soil4 ,at ! surface !y are v abundant1 especially if ! soil is moi/ & full ( organic mat]ial4 ,! numb] may range f a few hundr$ to "o hundr$ millions p] gramme4 ,footnote3 ,"o gramme is fifte5 gra9s4 ,! soil bact]ia v>y also 9 species1 "s two-score diff]5t species hav+ be5 describ$ z common 9 soil4 ,!y are 9 all bodies ( wat]1 bo? at ! surface & bel[ x4 ,!y are f\nd at consid]able dep?s 9 ! ocean4 ,all bodies ( fre% wat] conta9 !m1 & all s$im5ts 9 su* bodies ( wat] are fill$ ) bact]ia4 ,!y are 9 /reams ( runn+ wat] 9 ev5 great] quantity ?an 9 /&+ wat]4 ,?is is simply because runn+ /reams are be+ con/antly suppli$ ) wat] :i* has be5 wa%+ ! surface ( ! c\ntry & ?us c>ry+ (f all surface accumulations4 ,lakes or res]voirs1 h[ev]1 by /&+ quiet all[ ! bact]ia to settle to ! bottom1 & ! wat] ?us gets some:at purifi$4 ,!y are 9 ! air1 especially 9 regions ( habitation4 ,_! numb]s are greate/ ne> ! surface ( ! gr\nd1 & decrease 9 ! upp] /rata ( air4 ,any?+ :i* t5ds to raise du/ increases ! numb] ( bact]ia 9 ! air greatly1 & ! du/ & emanations f ! clo!s ( p cr[d$ 9 a close room fill ! air ) bact]ia 9 v great numb]s4 ,!y are f\nd 9 excessive abundance 9 e bit ( decay+ matt] :]ev] x may be4 ,manure heaps1 dead bodies ( animals1 decay+ trees1 fil? & slime & muck ev]y:]e are fill$ ) !m1 = x is 9 su* places t !y f9d _! be/ n\ri%m5t4 ,! bodies ( animals conta9 !m 9 ! m\?1 /oma*1 & inte/9e 9 great numb]s1 & ?is is1 ( c\rse1 equally true ( man4 ,on ! surface ( ! body !y cl+ 9 great quantity2 atta*$ to ! clo!s1 "u ! f+] nails1 among ! hairs1 9 e possible crevice or hid+ place 9 ! sk91 & 9 all secretions4 ,!y d n1 h[ev]1 occur 9 ! tissues ( a heal?y individual1 ei!r 9 ! blood1 muscle1 gl&1 or any o!r organ4 ,secretions1 su* z milk1 ur9e1 etc41 always conta9 !m1 h[ev]1 s9ce ! bact]ia d exi/ 9 ! ducts ( ! gl&s :i* conduct ! secretions to ! ext]ior1 & ?us1 :ile ! bact]ia are nev] 9 ! heal?y gl& itself1 !y always succe$ 9 contam9at+ ! secretion z x passes to ! ext]ior4 ,n only high] animals1 b ! l[] animals also h _! bodies m or less cov]$ ) bact]ia4 ,flies h !m on _! feet1 bees among _! hairs1 etc4 ,9 %ort1 :]ev] on ! face ( ,nature !re is a lodg+ place = du/ !re w be f\nd bact]ia4 ,9 mo/ ( ^! localities !y are dormant1 or at lea/ gr[+ only a little4 ,! bact]ia cl++ to ! dry hair c gr[ b little1 if at all1 & ^? 9 pure wat] multiply v little4 ,:5 dri$ z du/ !y are entirely dormant4 ,b ea* individual bact]ium or spore has ! pot5tial p[] ( multiplication already notic$1 & z soon z x by accid5t falls ^u a place :]e !re is food & moi/ure x w beg9 to multiply4 ,ev]y:]e 9 ,nature1 !n1 exi/s ?is gr\p ( organisms ) its almo/ inconceivable p[] ( multiplication1 b a p[] held 9 *eck by lack ( food4 ,furni% !m ) food & _! pot5tial p[]s become actual4 ,su* food is provid$ by ! dead bodies ( animals or plants1 or by animal secretions1 or f v>i\s o!r s\rces4 ,! bact]ia :i* are =tunate en\gh to get furni%$ ) su* food mat]ial cont9ue to fe$ ^u x until ! food supply is exhau/$ or _! gr[? is *eck$ 9 "s o!r way4 ,!y may be reg>d$1 !re=e1 z a con/ant & univ]sal p[] usually held 9 *eck4 ,) _! univ]sal pres5ce & _! p[]s ( produc+ *emical *anges 9 food mat]ial1 !y are ev] ready to produce *anges 9 ! face ( ,nature1 & to ^! *anges we w n[ turn4 ,,*apt] ,,ii4 ,,miscellane\s ,,use ,,( ,,bact]ia ,,9 ,,! ,,arts4 ,! foods ^u :i* bact]ia live are 9 endless v>iety1 almo/ e product ( animal or vegetable life s]v+ to supply _! ne$s4 ,"s species appe> to require some:at def9ite k9ds ( food1 & h !re=e r n>r[ conditions ( life1 b ! majority may live ^u a great v>iety ( organic comp\nds4 ,z !y consume ! mat]ial :i* s]ves !m z food !y produce *emical *anges !re94 ,^! *anges are l>gely ( a nature t ! *emi/ kn[s z decomposition *anges4 ,by ?is is meant t ! bact]ia1 seiz+ hold ( +r$i5ts :i* con/itute _! food1 break !m to pieces *emically4 ,! molecule ( ! orig9al food matt] is split into simpl] molecules1 & ! food is ?us *ang$ 9 its *emical nature4 ,z a result1 ! comp\nds :i* appe> 9 ! decompos+ solution are commonly simpl] ?an ! orig9al food molecules4 ,su* products are 9 g5]al call$ decomposition products1 or sometimes cleavage products4 ,sometimes1 h[ev]1 ! bact]ia h1 9 addition to _! p[] ( pull+ _! food to pieces1 a fur!r p[] ( build+ o!r comp\nds out ( ! fragm5ts1 ?us build+ up z well z pull+ d[n4 ,b1 h[ev] !y d x1 bact]ia :5 gr[+ 9 any food mat]ial h ! p[] ( giv+ rise to num]\s products :i* did n exi/ 9 ! food mass be=e4 ,because ( _! extraord9>y p[]s ( reproduction !y are capable ( produc+ ^! *anges v rapidly & c give rise 9 a %ort "t to l>ge am\nts ( ! peculi> products ( _! gr[?4 ,x is to ^! p[]s ( produc+ *emical *anges 9 _! food t bact]ia owe all _! importance 9 ! _w4 ,_! p[] ( *emically de/roy+ ! food products is 9 itself ( no little importance1 b ! products :i* arise z ! result ( ?is s]ies ( *emical *anges are ( an importance 9 ! _w :i* we are only j beg9n+ to appreciate4 ,9 our attempt to outl9e ! ag5cy :i* bact]ia play 9 our indu/ries & 9 natural processes z well1 we %all notice t !y are sometimes ( value simply = _! p[] ( produc+ decomposition2 b _! greate/ value lies 9 ! fact t !y are important ag5ts because ( ! products ( _! life4 ,we may notice1 9 ! fir/ place1 t 9 ! arts !re are sev]al indu/ries :i* may prop]ly be class$ toge!r z mac]ation indu/ries1 all ( :i* are bas$ ^u ! decomposition p[]s ( bact]ia4 ,h>dly any animal or vegetable sub/ance is able to resi/ _! s(t5+ influ5ce1 & ! artisan relies ^u ?is p[] 9 sev]al diff]5t directions4 ,,b5efits ,,d]iv$ ,,f ,,p[]s ,,( ,,decomposition4 ,l954--,l95 consi/s ( c]ta9 woody fibres ( ! /em ( ! flax4 ,! flax /em is n made up entirely ( ! valuable fibres1 b l>gely ( m brittle wood fibres1 :i* are ( no use4 ,! valuable fibres are1 h[ev]1 closely unit$ ) ! wood & ) ea* o!r 9 su* an intimate fa%ion t x is impossible to sep>ate !m by any me*anical means4 ,! :ole cellul> sub/ance ( ! /em is b\nd toge!r by "s cem5t+ mat]ials :i* hold x 9 a compact mass1 probably a salt ( calcium & pect9ic acid4 ,! art ( prep>+ flax is a process ( gett+ rid ( ! wor?less wood fibres & pres]v+ ! valuable1 long]1 t\gh]1 & m valuable fibres1 :i* are !n made into l954 ,b to sep>ate !m x is necess>y fir/ to s(t5 ! :ole tissue4 ,?is is always done ?r\gh ! aid ( bact]ia4 ,! flax /ems1 aft] prop] prep>ation1 are expos$ to ! action ( moi/ure & heat1 :i* soon develops a rapid bact]ial gr[?4 ,sometimes ?is is done by simply expos+ ! flax to ! dew & ra9 & all[+ x to lie ?us expos$ = "s "t4 ,by ano!r process ! /ems are completely imm]s$ 9 wat] & all[$ to rema9 = t5 to f\rte5 days4 ,by a ?ird process ! wat] 9 :i* ! flax is imm]s$ is heat$ f #ge degrees to #ij degrees ,f41 ) ! addition ( c]ta9 *emicals1 = "s fifty to sixty h\rs4 ,9 all cases ! effect is ! same4 ,! moi/ure & ! heat cause a gr[? ( bact]ia :i* proce$s ) m or less rapidity accord+ to ! temp]ature & o!r conditions4 ,a putrefactive f]m5tation is ?us set up :i* s(t5s ! gummy sub/ance hold+ ! fibres toge!r4 ,! process is kn[n z rett+1 & aft] x is complet$ ! fibres are easily isolat$ f ea* o!r4 ,a purely me*anical process n[ easily sep>ates ! valuable fibres f ! wood fibres4 ,! :ole process is a typical f]m5tation4 ,a disagreeable od\r arises f ! f]m5t+ flax1 & ! liquid aft] ! f]m5tation is fill$ ) products :i* make valuable manure4 ,! process has n be5 sci5tifically /udi$ until v rec5tly4 ,! bacillus :i* produces ! rett+ is kn[n n[1 h[ev]1 & x has be5 %[n t ! rett+ is a process ( decomposition ( ! pect9 cem5t4 ,no me?od ( sep>at+ ! l95 fibres 9 ! flax f ! wood fibres has yet be5 devis$ :i* disp5ses ) ! aid ( bact]ia4 ,jute & ,hemp4--,almo/ exactly ! same use is made ( bact]ial action 9 ! manufacture ( jute und hemp4 ,! comm]cial aspect ( ! jute indu/ry has gr[n to be a l>ge "o1 involv+ _m millions ( doll>s4 ,l l951 jute is a fibre ( ! inn] b>k ( a plant1 & is mix$ 9 ! b>k ) a mass ( o!r useless fibr\s mat]ial4 ,z 9 ! case ( l951 a f]m5tation by bact]ia is dep5d$ ^u z a means ( s(t5+ ! mat]ial s t ! fibres c be disassociat$4 ,! process is call$ rett+1 z 9 ! l95 manufacture4 ,! details ( ! process are some:at diff]5t4 ,! jute is commonly f]m5t$ 9 tanks ( /agnant wat]1 al?\gh sometimes x is all[$ to soak 9 riv] wat] = a suffici5t l5g? ( "t to produce ! s(t5+4 ,aft] ! f]m5tation is ?us />t$ ! jute fibre is sep>at$ f ! wood1 & is ( a suffici5t flexibility & t\ghness to be wov5 into sack+1 c>pets1 curta9s1 table cov]s1 & o!r co>se clo?4 ,practically ! same me?od is us$ 9 sep>at+ ! t\gh fibres ( ! hemp4 ,! hemp plant conta9s "s long flexible fibres ) o!rs ( no value1 & bact]ial f]m5tation is reli$ ^u to s(t5 ! tissues s t !y may be sep>at$4 ,cocoanut fibre1 a some:at simil> mat]ial is obta9$ f ! husk ( ! cocoanut by ! same means4 ,! unrip5$ husk is all[$ to /eep & f]m5t 9 wat] = a long "t1 six mon?s or a ye> be+ requir$4 ,by ?is "t ! husk has become s s(t5$ t x c be beat5 until ! fibres sep>ate & c be remov$4 ,!y are subsequ5tly made into a numb] ( co>se articles1 especially valuable = _! t\ghness4 ,door mats1 bru%es1 %ips' f5d]s1 etc41 are illu/rations ( ! sort ( articles made f !m4 ,9 ea* ( ^! processes ! f]m5tation mu/ h a t5d5cy to s(t5 ! desir$ fibres z well z ! connect+ sub/ance4 ,putrefaction attacks all k9ds ( vegetable tissue1 & if ?is rett+ cont9ues too long ! desir$ fibre is decid$ly injur$ by ! s(t5+ effect ( ! f]m5tation4 ,x is q probable t1 ev5 z commonly c>ri$ on1 ! f]m5tation has "s slight injuri\s effect ^u ! fibre1 & t if "s purely me*anical means c\ld be devis$ = sep>at+ ! fibre f ! wood x w\ld produce a bett] mat]ial4 ,b su* me*anical means has n be5 devis$1 & at pres5t a putrefactive f]m5tation appe>s to be ! only practical me?od ( sep>at+ ! fibres4 ,sponges4--,a some:at simil> use is made ( bact]ia 9 ! comm]cial prep>ation ( sponges4 ,! sponge ( comm]ce is simply ! fibr\s skeleton ( a m>9e animal4 ,:5 x is alive ?is skeleton is completely fill$ ) ! s(t] p>ts ( ! animal1 & to fit ! sponge = use ?is s(t] organic mat]ial mu/ be got rid (4 ,x is easily accompli%$ by rott+4 ,! fre% sponges are all[$ to /& 9 ! w>m sun & v rapidly decay4 ,bact]ia make _! way into ! sponge & ?or\ghly decompose ! s(t tissues4 ,aft] a %ort putrefaction ( ?is sort ! s(t5$ organic matt] c be easily wa%$ out ( ! skeleton & leave ! clean fibre ready = m>ket4 ,lea!r prep>ation4--,! tann+ ( lea!r is a purely *emical process1 & 9 "s processes ! :ole op]ation ( prep>+ ! lea!r is a *emical "o4 ,9 o!rs1 h[ev]1 especially 9 ,am]ica1 bact]ia are br\ght into action at "o /age4 ,! dri$ hide :i* comes to ! tann]y mu/ fir/ h ! hair remov$ toge!r ) ! out] sk94 ,! hide = ?is purpose mu/ be moi/5$ & s(t5$4 ,9 "s tann]ies ?is is done by /eep+ x 9 *emicals4 ,9 o!rs1 h[ev]1 x is put into wat] & slightly heat$ until f]m5tation arises4 ,! f]m5tation s(t5s x s t ! out] sk9 c be easily remov$ ) a knife1 & ! removal ( hair is accompli%$ at ! same "t4 ,bact]ial putrefaction 9 ! tann]y is ?us an assi/ance 9 prep>+ ! sk9 = ! tann+ prop]4 ,ev5 9 ! subsequ5t tann+ a bact]ial f]m5tation appe>s to play a "p1 b little is yet kn[n 9 reg>d to x4 ,mac]ation ( skeletons4--,! mak+ ( skeletons = museums & anatomical in/ruction 9 g5]al is no v great indu/ry1 & yet x is "o ( importance4 ,9 ! mak+ ( skeletons ! process ( mac]ation is commonly us$ z an aid4 ,! mac]ation consi/s simply 9 all[+ ! skeleton to soak 9 wat] = a day or two aft] clean+ away ! bulk ( ! muscles4 ,! putrefaction t arises s(t5s ! connective tissues s mu* t ! bones may be readily clean$ ( fle%4 ,citric acid4--,bact]ial f]m5tation is employ$ also 9 ! ord9>y prep>ation ( citric acid4 ,! acid is made *iefly f ! juice ( ! lemon4 ,! juice is press$ f ! fruit & !n all[$ to f]m5t4 ,! f]m5tation aids 9 sep>at+ a mucilag9\s mass & mak+ x ?us possible to obta9 ! citric acid 9 a pur] condition4 ,! action is probably simil> to ! mac]ation processes describ$ above1 al?\gh x has n z yet be5 /udi$ by bact]iologi/s4 ,,b5efits ,,d]iv$ ,,f ,,! ,,products ,,( ,,bact]ial ,,life4 ,:ile bact]ia ?us play a "p 9 our indu/ries simply f _! p[] ( produc+ decomposition1 x is prim>ily because ( ! products ( _! action t !y are ( value4 ,:]ev] bact]ia seize hold ( organic matt] & fe$ ^u x1 !re are c]ta9 to be develop$ new *emical comp\nds1 result+ l>gely f decomposition1 b p>tly also f con/ructive processes4 ,^! new comp\nds are ( great v>iety4 ,diff]5t species ( bact]ia d n by any means produce ! same comp\nds ev5 :5 gr[+ 9 & decompos+ ! same food mat]ial4 ,moreov]1 ! same species ( bact]ia may give rise to diff]5t products :5 gr[+ 9 diff]5t food mat]ials4 ,"s ( ! comp\nds produc$ by su* processes are poison\s1 o!rs are h>mless4 ,"s are gase\s1 o!rs are liquids4 ,"s h peculi> od\rs1 z may be recognis$ f ! smell aris+ f a bit ( decay+ meat4 ,o!rs h peculi> ta/es1 z may be realiz$ 9 ! gamy ta/e ( meat :i* is 9 ! incipi5t /ages ( putrefaction4 ,by purely empirical means mank9d has le>n$ me?ods ( enc\rag+ ! developm5t ( "s ( ^! products1 & is to-day mak+ practical use ( ?is p[]1 possess$ by bact]ia1 ( furni%+ desir$ *emical comp\nds4 ,indu/ries involv+ ! inve/m5t ( hundr$s ( millions ( doll>s are f\nd$ ^u ! products ( bact]ial life1 & !y h a f> m important relation to our ev]yday life ?an is commonly imag9$4 ,9 _m cases ! artisan :o is dep5d5t ^u ?is action ( microscopic life is unaw>e ( ! fact4 ,8 processes are ^? :i* exp]i5ce has taught produce desir$ results1 b1 nev]!less1 8 dep5d5ce ^u bact]ia is none ! less fundam5tal4 ,,bact]ia ,,9 ,,! ,,f]m5tative ,,indu/ries4 ,we may notice1 fir/1 sev]al miscellane\s in/ances ( ! application ( bact]ia to v>i\s f]m5tative indu/ries :]e _! aid is ( m or less value to man4 ,9 "s ( ! examples to be m5tion$ ! influ5ce ( bact]ia is pr(\nd & fundam5tal1 :ile 9 o!rs x is only incid5tal4 ,! f]m5tative indu/ries ( civilization are gigantic 9 ext5t1 & h come to be an important factor 9 mod]n civiliz$ life4 ,! l>ge "p ( ! f]m5tation is bas$ ^u ! gr[? ( a class ( microscopic plants :i* we call yea/s4 ,bact]ia & yea/s are bo? microscopic plants1 & p]haps some:at closely relat$ to ea* o!r4 ,! botani/ f9ds a diff]5ce betwe5 !m1 bas$ ^u _! me?od ( multiplication1 & !re=e places !m 9 diff]5t classes 7,fig4 #b1 page #ai74 ,9 _! g5]al p[] ( produc+ *emical *anges 9 _! food products1 yea/s agree closely ) bact]ia1 ?\gh ! k9ds ( *emical *anges are diff]5t4 ,! :ole ( ! great f]m5tative indu/ries1 9 :i* are inve/$ hundr$s ( millions ( doll>s1 is bas$ ^u *emical decompositions produc$ by microscopic plants4 ,9 ! great "p ( comm]cial f]m5tations alcohol is ! product desir$1 & alcohol1 ?\gh x is sometimes produc$ by bact]ia1 is 9 comm]cial quantities produc$ only by yea/s4 ,h5ce x is t1 al?\gh ! f]m5tations produc$ by bact]ia are m common 9 ,nature ?an ^? produc$ by yea/s & give rise to a mu* l>g] numb] ( decomposition products1 /ill _! comm]cial aspect is decid$ly less important ?an t ( yea/s4 ,nev]!less1 bact]ia are n )\t _! importance 9 ! ord9>y f]m5tative processes4 ,al?\gh !y are ( no importance z aids 9 ! common f]m5tative processes1 !y are n infrequ5tly ! cause ( mu* tr\ble4 ,9 ! f]m5tation ( malt to produce be]1 or grape juice to produce w9e1 x is ! desire ( ! brew] & v9tn] to h ?is f]m5tation produc$ by pure yea/s1 unmix$ ) bact]ia4 ,if ! yea/ is pure ! f]m5tation is uni=m & successful4 ,b ! brew] & v9tn] h long kn[n t ! f]m5tation is frequ5tly int]f]$ ) by irregul>ities4 ,! tr\bles :i* arise h long be5 kn[n1 b ! bact]iologi/ has f9ally discov]$ _! cause1 & 9 g5]al _! rem$y4 ,! cause ( ! *ief tr\bles :i* arise 9 ! f]m5tation is ! pres5ce ( contam9at+ bact]ia among ! yea/s4 ,^! bact]ia h be5 m or less c>efully /udi$ by bact]iologi/s1 & _! effect ^u ! be] or w9e det]m9$4 ,"s ( !m produce acid & r5d] ! products s\r2 o!rs make !m bitt]2 o!rs1 aga91 produce a slimy mat]ial :i* makes ! w9e or be] ropy4 ,some?+ l a score ( bact]ia species h be5 f\nd liable to occur 9 ! f]m5t+ mat]ial & de/roy ! value ( ! product ( bo? ! w9e mak] & ! be] brew]4 ,! species ( bact]ia :i* infect & injure w9e are diff]5t f ^? :i* infect & injure be]4 ,!y are ev] pres5t z possibilities 9 ! great alcoholic f]m5tations4 ,!y are dang]s :i* mu/ be gu>d$ aga9/4 ,9 =m] ye>s ! tr\bles f ^! s\rces 7 mu* great] ?an !y are at pres5t4 ,s9ce x has be5 demon/rat$ t ! diff]5t imp]fections 9 ! f]m5tative process are due to bact]ial impurities1 commonly 9 ! yea/s :i* are us$ to produce ! f]m5tation1 me?ods ( avoid+ !m are readily devis$4 ,to-day ! v9tn] has ready comm& ( processes = avoid+ ! tr\bles :i* arise f bact]ia1 & ! brew] is always provid$ ) a microscope to %[ him ! pres5ce or abs5ce ( ! contam9at+ bact]ia4 ,:ile1 !n1 ! alcoholic f]m5tations are n dep5d5t ^u bact]ia1 ! prop] managem5t ( ^! f]m5tations requires a k ( _! habits & *>act]s4 ,!re are c]ta9 o!r f]m5tative processes ( m or less importance 9 _! comm]cial aspects1 :i* are directly dep5d5t ^u bact]ial action1 ,"s ( !m we %\ld unhesitat+ly look ^u z f]m5tations1 :ile o!rs w\ld h>dly be ?\ght ( z belong+ to ! f]m5tation indu/ries4 ,,v9eg>4 ,! comm]cial importance ( ! manufacture ( v9eg>1 ?\gh l>ge1 does n1 ( c\rse1 comp>e 9 ext5t ) t ( ! alcoholic f]m5tations4 ,v9eg> is a weak solution ( acetic acid1 toge!r ) v>i\s o!r +r$i5ts :i* h come f ! mat]ials furni%+ ! acid4 ,9 ! manufacture ( v9eg>1 alcohol is always us$ z ! s\rce ( ! acetic acid4 ,! production ( acetic acid f alcohol is a simple oxidation4 ,! equation ,c#b;,h#f,o ,o#b ,c#b;,h#d,o#b ,h#b,o %[s ! *emical *ange t occurs4 ,?is oxidation c be br\ght ab\t by purely *emical means4 ,:ile alcohol w n readily unite ) oxyg5 "u common conditions1 if ! alcohol is all[$ to pass ov] a bit ( plat9um sponge ! union readily occurs & acetic acid results4 ,?is me?od ( acetic-acid production is possible exp]im5tally1 b is impracticable on any l>ge scale4 ,9 ! ord9>y manufacture ( v9eg> ! oxidation is a true f]m5tation1 & br\ght ab\t by ! gr[? ( bact]ia4 ,9 ! comm]cial manufacture ( v9eg> sev]al diff]5t weak alcoholic solutions are us$4 ,! mo/ common ( ^! are f]m5t$ malt1 weak w9e1 cid]1 & sometimes a weak solution ( _s to :i* is add$ sug> & malt4 ,if ^! solutions are all[$ to /& = a "t 9 contact ) air1 !y sl[ly turn s\r by ! gradual conv]sion ( ! alcohol into acetic acid4 ,at ! close ( ! process practically all ( ! alcohol has disappe>$4 ,ord9>ily1 h[ev]1 n all ( x has be5 conv]t$ into acetic acid1 = ! oxidation does n all /op at ?is /ep4 ,z ! oxidation goes on1 "s ( ! acid is oxidiz$ into c>bonic dioxide1 :i* is1 ( c\rse1 dissipat$ at once into ! air1 & if ! process is all[$ to cont9ue un*eck$ = a long en\gh p]iod mu* ( ! acetic acid w be lo/ 9 ?is way4 ,! oxidation ( ! alcohol 9 all comm]cial production ( v9eg> is br\ght ab\t by ! gr[? ( bact]ia 9 ! liquid4 ,:5 ! v9eg> production is go+ on prop]ly1 !re is =m$ on ! top ( ! liquid a d5se felt$ mass kn[n z ! "m ( v9eg>4 ,?is mass proves to be made ( bact]ia :i* h ! p[] ( absorb+ oxyg5 f ! air1 or1 at all ev5ts1 ( caus+ ! alcohol to unite ) oxyg54 ,x 0 at fir/ ?\ght t a s+le species ( bact]ium 0 ?us ! cause ( ! oxidation ( alcohol1 & ?is 0 nam$ ,mycod]ma aceti4 ,b fur!r /udy has %[n t sev]al h ! p[]1 & t ev5 9 ! comm]cial manufacture ( v9eg> sev]al species play a "p 7,fig4 #ah71 al?\gh ! diff]5t species are n yet v ?or\ghly /udi$4 ,ea* appe>s to act be/ "u diff]5t conditions4 ,"s ( !m act sl[ly1 & o!rs rapidly1 ! sl[- gr[+ species appe>+ to produce ! l>g] am\nt ( acid 9 ! end4 ,aft] ! am\nt ( acetic acid rea*es a c]ta9 p]c5tage1 ! bact]ia are unable to produce m1 ev5 ?\gh !re be alcohol /ill left unoxidiz$4 ,a p]c5tage z high z f\rte5 p] c5t1 commonly de/roys all _! p[] ( gr[?4 ,! production ( ! acid is :olly dep5d5t ^u ! gr[? ( ! bact]ia1 & ! secret ( ! successful v9eg> manufacture is ! skilful manipulation ( ^! bact]ia s z to keep !m 9 ! pure/ condition & to give !m ! be/ opportunity = gr[?4 ,"o me?od ( v9eg> manufacture :i* is q rapid is c>ri$ on 9 a slightly diff]5t mann]4 ,a tall cyl9drical *amb] is fill$ ) wood %av+s1 & a weak solution ( alcohol is all[$ to trickle sl[ly ?r\gh x4 ,! liquid aft] pass+ ov] ! %av+s comes out aft] a numb] ( h\rs well *>g$ ) acetic acid4 ,?is process at fir/ sight appe>s to be a purely *emical "o1 & rem9ds u ( ! oxidation :i* occurs :5 alcohol is all[$ to pass ov] a plat9um sponge4 ,x has be5 claim$1 inde$1 t ?is is a *emical oxidation 9 :i* bact]ia play no "p4 ,b ?is appe>s to be an error4 ,x is always f\nd necess>y 9 ?is me?od to />t ! process by p\r+ ^u ! %av+s "s w>m v9eg>4 ,unless 9 ?is way ! %av+s become *>g$ ) ! v9eg>-hold+ bact]ia ! alcohol w n und]go oxidation dur+ its passage ov] !m1 & aft] ! bact]ia ?us introduc$ h gr[n en\gh to coat ! %av+s ?or\ghly ! acetic-acid production is mu* m rapid ?an at fir/4 ,if v9eg> is all[$ to trickle sl[ly d[n a susp5d$ /r+1 s t its bact]ia may di/ribute !mselves ?r\gh ! /r+1 & !n alcohol be all[$ to trickle ov] x 9 ! same way1 ! oxidation takes place & acetic acid is =m$4 ,f ! accumulation ( su* facts x has come to be recognis$ t all processes = ! comm]cial manufacture ( v9eg> dep5d ^u ! action ( bact]ia4 ,:ile ! oxidation ( alcohol into acetic acid may take place by purely *emical means1 ^! processes are n practical on a l>ge scale1 & v9eg> manufactur]s ev]y:]e dep5d ^u bact]ia z _! ag5ts 9 produc+ ! oxidation4 ,^! bact]ia1 sev]al species 9 all1 fe$ ^u ! nitrog5\s matt] 9 ! f]m5t+ mass & produce ! desir$ *ange 9 ! alcohol4 ,?is v9eg> f]m5tation is subject to c]ta9 irregul>ities1 & ! v9eg> manufactur]s c n always dep5d ^u its occurr+ 9 a satisfactory mann]4 ,j z 9 brew+1 s "h1 contam9at+ bact]ia sometimes f9d _! way into ! f]m5t+ mass & int]f]e ) its normal c\rse4 ,9 p>ticul>1 ! flav\r ( ! v9eg> is liable to suff] f su* causes4 ,z yet our v9eg> manufactur]s h n appli$ to acetic f]m5tation ! same pr9ciple :i* has be5 s successful 9 brew+--namely1 ! use1 z a />t] ( ! f]m5tation1 ( a pure culture ( ! prop] species ( bact]ia4 ,?is has be5 done exp]im5tally & proves to be feasible4 ,9 practice1 h[ev]1 v9eg> mak]s f9d t simpl] me?ods ( obta9+ a />t]--by means ( :i* !y procure a culture ne>ly ?\gh n absolutely pure--are p]fectly satisfactory4 ,x is unc]ta9 :e!r really pure cultures w ev] be us$ 9 ?is indu/ry4 ,,lactic ,,acid4 ,! manufacture ( lactic acid is an indu/ry ( less ext5t ?an t ( acetic acid1 & yet x is "o :i* has "s consid]able comm]cial importance4 ,lactic acid is us$ 9 no l>ge quantity1 al?\gh x is ( "s value z a m$ic9e & 9 ! arts4 ,= its production we are :olly dep5d5t ^u bact]ia4 ,x is ?is acid :i*1 z we %all see1 is produc$ 9 ! ord9>y s\r+ ( milk1 & a l>ge numb] ( species ( bact]ia are capable ( produc+ ! acid f milk sug>4 ,any sample ( s\r milk may !re=e always be dep5d$ ^u to conta9 pl5ty ( lactic organisms4 ,9 its manufacture = comm]cial purposes milk is sometimes us$ z a s\rce1 b m commonly o!r sub/ances4 ,sometimes a mixture ( cane sug> & t>t>ic acid is us$4 ,to />t ! f]m5tation ! mixture is inoculat$ ) a mass ( s\r milk or decay+ *eese1 or bo?1 su* a mixture always conta9+ lactic organisms4 ,to be sure1 x also conta9s _m o!r bact]ia :i* h diff]5t effects1 b ! acid produc]s are always s abundant & gr[ s vigor\sly t ! lactic f]m5tation occurs 9 spite ( all o!r bact]ia4 ,"h also !re is a possibility ( an improvem5t 9 ! process by ! use ( pure cultures ( lactic organisms4 ,up to ! pres5t1 h[ev]1 !re has be5 no application ( su* me?ods4 ,! comm]cial aspects ( ! indu/ry are n ^u a suffici5tly l>ge scale to call = mu* 9 ?is direction4 ,at ! pres5t "t ! only me?od we h = ! manufacture ( lactic acid is dep5d5t ^u bact]ia4 ,*emical processes = its manufacture are kn[n1 b n employ$ comm]cially4 ,!re are sev]al diff]5t k9ds ( lactic acid4 ,!y diff] f ea* o!r 9 ! relations ( ! atoms )9 _! molecule1 & 9 _! relation to pol>iz$ light1 "s =ms rotat+ ! plane ( pol>iz$ light to ! "r1 o!rs to ! left1 :ile o!rs are inactive 9 ?is respect4 ,all ! types are produc$ by f]m5tation processes1 diff]5t species ( bact]ia hav+ p[]s ( produc+ ! diff]5t types4 ,,butyric ,,acid4 ,butyric acid is ano!r acid = :i* we are *iefly dep5d5t ^u bact]ia4 ,?is acid is ( no v great importance1 & its manufacture c h>dly be call$ an indu/ry2 /ill x is to a c]ta9 ext5t made1 & is an article ( comm]ce4 ,x is an acid t c be manufactur$ by *emical means1 b1 z 9 ! case ( ! la/ two acids1 its comm]cial manufacture is bas$ ^u bact]ial action4 ,q a numb] ( species ( bact]ia c produce butyric acid1 & !y produce x f a v>iety ( diff]5t s\rces4 ,butyric acid is a common +r$i5t 9 old milk & 9 butt]1 & its =mation by bact]ia 0 hi/orically "o ( ! fir/ bact]ial f]m5tations to be cle>ly und]/ood4 ,x c be produc$ also 9 v>i\s sug> & />*y solutions4 ,glyc]9e may also und]go a butyric f]m5tation4 ,! pres5ce ( ?is acid is occasionally tr\blesome1 s9ce x is "o ( ! factors 9 ! rancidity ( butt] & o!r simil> mat]ials4 ,,indigo ,,prep>ation4 ,! prep>ation ( indigo f ! indigo plant is a f]m5tative process br\ght ab\t by a specific bact]ium4 ,! leaves ( ! plant are imm]s$ 9 wat] 9 a l>ge vat1 & a rapid f]m5tation arises4 ,z a result ( ! f]m5tation ! "p ( ! plant :i* is ! basis ( ! indigo is sep>at$ f ! leaves & dissolv$ 9 ! wat]2 & z a second feature ( ! f]m5tation ! soluble mat]ial is *ang$ 9 its *emical nature into indigo prop]4 ,z ?is *ange occurs ! *>act]i/ic blue col\r is develop$1 & ! mat]ial is r5d]$ insoluble 9 wat]4 ,x !re=e makes its appe>ance z a blue mass sep>at$ f ! wat]1 & is !n remov$ z indigo4 ,( ! nature ( ! process we z yet "k v little4 ,t x is a f]m5tation is c]ta91 & x has be5 prov$ t x is produc$ by a def9ite species ( bact]ium :i* occurs on ! indigo leaves4 ,if ! /]iliz$ leaves are plac$ 9 /]ile wat] no f]m5tation occurs & no indigo is =m$4 ,if1 h[ev]1 "s ( ! specific bact]ia are add$ to ! mass ! f]m5tation soon beg9s & ! blue col\r ( ! indigo makes its appe>ance4 ,x is pla91 !re=e1 t indigo is a product ( bact]ial f]m5tation1 & commonly due to a s+le def9ite species ( bact]ium4 ,( ! details ( ! =mation1 h[ev]1 we z yet "k little1 & no practical application ( ! facts h yet be5 made4 ,,bact]ia ,,9 ,,tobacco ,,cur+4 ,a f]m5tative process ( q a diff]5t nature1 b ( imm5se comm]cial value1 is f\nd 9 ! prep>ation ( tobacco4 ,! process by :i* tobacco is prep>$ is a long & some:at complicat$ "o1 consi/+ ( a numb] ( diff]5t /ages4 ,! tobacco1 aft] be+ fir/ dri$ 9 a c>eful mann]1 is subsequ5tly all[$ to absorb moi/ure f ! atmosph]e1 & is !n plac$ 9 l>ge heaps to und]go a fur!r *ange4 ,?is process appe>s to be a f]m5tation1 = ! temp]ature ( ! mass rises rapidly1 & e indication ( a f]m5tative action is se54 ,! tobacco 9 ^! heaps is *ang$ occasionally1 ! heap be+ ?r[n d[n & built up aga9 9 su* a way t ! portion :i* 0 fir/ at ! bottom comes to ! top1 & 9 ?is way all p>ts ( ! heap may become equally affect$ by ! process4 ,aft] ?is process ! tobacco is s5t to ! diff]5t manufactur]s1 :o f9i% ! process ( cur+4 ,! fur!r treatm5t x receives v>ies widely accord+ to ! desir$ product1 :e!r = smok+ or = snuff1 etc4 ,9 all cases1 h[ev]1 f]m5tations play a prom95t "p4 ,sometimes ! leaves are directly inoculat$ ) f]m5t+ mat]ial4 ,9 ! prep>ation ( snuff ! details ( ! process are m complicat$ ?an 9 ! prep>ation ( smok+ tobacco4 ,! tobacco1 aft] be+ gr\nd & mix$ ) c]ta9 +r$i5ts1 is all[$ to und]go a f]m5tation :i* la/s = weeks1 & inde$ = mon?s4 ,9 ! diff]5t me?ods ( prep>+ snuff ! f]m5tations take place 9 diff]5t ways1 & sometimes ! tobacco is subject$ to two or ?ree diff]5t f]m5tative actions4 ,! result ( ! :ole is ! sl[ prep>ation ( ! comm]cial product4 ,x is dur+ ! f9al f]m5tative processes t ! peculi> col\r & flav\r ( ! snuff are develop$1 & x is dur+ ! f]m5tation ( ! leaves ( ! smok+ tobacco--ei!r ! orig9al f]m5tation or ! subsequ5t ones-- t ! special flav\rs & aromas ( tobacco are produc$4 ,x c n be claim$ = a mom5t t ^! *anges by :i* ! tobacco is cur$ & f9ally br\ght to a m>ketable condition are due :olly to bact]ia4 ,!re is no "q t *emical & physical ph5om5a play an important "p 9 !m4 ,nev]!less1 f ! mom5t :5 ! tobacco is cut 9 ! fields until ! "t x is ready = m>ket ! cur+ is v intimately associat$ ) bact]ia & f]m5tative organisms 9 g5]al4 ,"s ( ^! processes are :olly br\ght ab\t by bact]ial life2 9 o!rs ! micro-organisms aid ! process1 ?\gh !y p]haps c n be reg>d$ z ! sole ag5ts4 ,at ! outset ! tobacco produc] has to cont5d ) a numb] ( micro-organisms :i* may produce diseases 9 8 tobacco4 ,dur+ ! dry+ process1 if ! temp]ature or ! am\nt ( moi/ure or ! access ( air is n kept 9 a prop] condition1 v>i\s tr\bles arise & v>i\s diseases make _! appe>ance1 :i* ei!r injure or ru9 ! value ( ! product4 ,^! appe> to be produc$ by micro-organisms ( diff]5t sorts4 ,dur+ ! f]m5tation :i* foll[s ! dry+ ! produc] has to cont5d ) micro-organisms t are tr\blesome to him2 = unless ! ph5om5a are prop]ly regulat$ ! f]m5tation t occurs produces effects ^u ! tobacco :i* ru9 its "*4 ,f ! "t ! tobacco is cut until ! f9al /age 9 ! cur+ ! p]sons engag$ 9 prep>+ x = m>ket mu/ be on a con/ant wat* to prev5t ! gr[? )9 x ( undesirable organisms4 ,! prep>ation ( tobacco is = ?is reason a delicate op]ation1 & "o t w be v likely to fail unless ! greate/ c>e is tak54 ,9 ! sev]al f]m5tative processes :i* occur 9 ! prep>ation !re is no "q t micro-organisms aid ! tobacco produc] & manufactur]4 ,bact]ia produce ! fir/ f]m5tation t foll[s ! dry+1 & x is ^! organisms too1 9 l>ge measure1 t give rise to all ! subsequ5t f]m5tations1 al?\gh seem+ly 9 "s cases purely *emical processes mat]ially aid4 ,n[ ! special quality ( ! tobacco is 9 "p dep5d5t ^u ! peculi> type ( f]m5tation :i* occurs 9 "o or ano!r ( ^! f]m5t+ actions4 ,x is ! f]m5tation t gives rise to ! peculi> flav\r & to ! aroma ( ! diff]5t grades ( tobacco4 ,inasmu* z ! v>i\s flav\rs :i* *>act]ize tobacco ( diff]5t grades are develop$1 at lea/ to a l>ge ext5t1 dur+ ! f]m5tation processes1 x is a natural supposition t ! diff]5t qualities ( ! tobacco1 s f> z conc]ns flav\r1 are due to ! diff]5t types ( f]m5tation4 ,! numb] ( species ( bact]ia :i* are f\nd ^u ! tobacco leaves 9 ! v>i\s /ages ( its prep>ation is q l>ge1 & f :at we h already le>n$ x is inevitable t ! diff]5t k9ds ( bact]ia w produce diff]5t results 9 ! f]m5t+ process4 ,x w\ld seem natural1 !re=e1 to assume t ! diff]5t flav\rs ( diff]5t grades may n unlikely be due to ! fact t ! tobacco 9 ! diff]5t cases has be5 f]m5t$ "u ! influ5ce ( diff]5t k9ds ( bact]ia4 ,nor is ?is simply a matt] ( inf]5ce4 ,to a c]ta9 ext5t exp]im5tal evid5ce has borne out ! conclusion1 & has giv5 at lea/ a slight indication ( practical results 9 ! future4 ,act+ ^u ! sugge/ion t ! diff]5ce betwe5 ! high grades ( tobacco & ! poor] grades is due to ! "* ( ! bact]ia t produce ! f]m5tation1 c]ta9 bact]iologi/s h attempt$ to obta9 f a high quality ( tobacco ! species ( bact]ia :i* are infe/+ x4 ,^! bact]ia h !n be5 cultivat$ by bact]iological me?ods & us$ 9 exp]im5ts = ! f]m5tation ( tobacco4 ,if x is true t ! flav\r ( high grade tobacco is 9 l>ge measure1 or ev5 9 "p1 due to ! action ( ! peculi> microbes f ! soil :]e x gr[s1 x ought to be possible to produce simil> flav\rs 9 ! leaves ( tobacco gr[n 9 o!r localities1 if ! f]m5tation ( ! leaves is c>ri$ on by means ( ! pure cultures ( bact]ia obta9$ f ! high grade tobacco4 ,n v mu* has be5 done or is kn[n 9 ?is connection z yet4 ,two bact]iologi/s h exp]im5t$ indep5d5tly 9 f]m5t+ tobacco leaves by ! action ( pure cultures ( bact]ia obta9$ f su* s\rces4 ,ea* ( !m reports successful exp]im5ts4 ,ea* claims t !y h be5 able to improve ! quality ( tobacco by inoculat+ ! leaves ) a pure culture ( bact]ia obta9$ f tobacco hav+ high quality 9 flav\r4 ,9 addition to ?is1 sev]al o!r bact]iologi/s h c>ri$ on exp]im5ts suffici5t to indicate t ! flav\rs ( ! tobacco & ! "* ( ! rip5+ may be decid$ly *ang$ by ! use ( diff]5t species ( micro-organisms 9 ! f]m5tations t g on dur+ ! cur+ processes4 ,9 reg>d to ! :ole matt]1 h[ev]1 we mu/ recognise t z yet we h v little k4 ,! subject has be5 "u inve/igation = only a %ort "t2 &1 :ile consid]able in=mation has be5 d]iv$1 ?is in=mation is n ?or\ghly und]/ood1 & our k 9 reg>d to ! matt] is z yet 9 r a *aotic condition4 ,x seems c]ta91 h[ev]1 t ! quality ( tobacco is 9 l>ge measure dep5d5t ^u ! "* ( ! f]m5tations t occur at diff]5t /ages ( ! cur+4 ,x seems c]ta9 also t ^! f]m5tations are :olly or *iefly produc$ by microorganisms1 & t ! "* ( ! f]m5tation is 9 l>ge measure dep5d5t ^u ! species ( micro-organisms t produce x4 ,if ^! are facts1 x w\ld seem n improbable t a fur!r /udy may produce practical results = ?is great indu/ry4 ,! /udy ( yea/s & ! me?ods ( keep+ yea/ f contam9ations has revolutionis$ ! brew+ indu/ry4 ,p]haps 9 ?is o!r f]m5tative indu/ry1 :i* is ( su* great comm]cial ext5t1 ! use ( pure cultures ( bact]ia may 9 ! future produce z great revolutions 9 me?ods z x has 9 ! indu/ry ( ! alcoholic f]m5tation4 ,x mu/ n1 h[ev]1 be inf]r$ t ! diff]5ces 9 grades ( tobacco gr[n 9 diff]5t p>ts ( ! _w are due solely to v>iations 9 ! cur+ processes & to ! types ( f]m5tation4 ,!re are diff]5ces 9 ! texture ( ! leaves1 diff]5ces 9 ! *emical composition ( ! tobaccoes1 :i* are due und\bt$ly to ! soils & ! climatic conditions 9 :i* !y gr[1 & ^!1 ( c\rse1 w nev] be affect$ by *ang+ ! "* ( ! f]m5t active processes4 ,x is1 h[ev]1 probable t 9 s f> z ! flav\rs t di/+ui% ! high & l[ grades ( tobacco are due to ! "* ( ! f]m5tative processes1 !y may be 9 ! future1 at lea/ to a l>ge ext5t1 controll$ by ! use ( pure cultures 9 cur+ processes4 ,seem+ly1 !n1 !re is z great a future 9 ! developm5t ( ?is f]m5tative indu/ry z !re has be5 9 ! pa/ 9 ! developm5t ( ! f]m5tative indu/ry associat$ ) brew+ & v9t+4 ,,opium4 ,opium = smok+ purposes is commonly all[$ to und]go a cur+ process :i* la/s sev]al mon?s4 ,?is appe>s to be some:at simil> to ! cur+ ( tobacco4 ,app>5tly x is a f]m5tation due to ! gr[? ( microorganisms4 ,! organisms 9 "q are n1 h[ev]1 bact]ia 9 ?is case1 b a species ( alli$ fungus4 ,! plant is a m\ld1 & x is claim$ t inoculation ( ! opium ) cultures ( ?is m\ld ha/5s ! cur+4 ,,tr\blesome ,,f]m5tations4 ,be=e leav+ ?is bran* ( ! subject x is necess>y to notice "s ( ! tr\blesome f]m5tations :i* are ev] int]f]+ ) our indu/ries1 requir+ special me?ods1 or1 inde$1 sometimes develop+ special indu/ries to meet !m4 ,z ag5ts ( decomposition1 bact]ia w ( c\rse be a tr\ble :5ev] !y get into mat]ial :i* x is desir$ to pres]ve4 ,s9ce !y are abundant ev]y:]e1 x is necess>y to c\nt ^u _! attack+ ) c]ta9ty any f]m5table sub/ance :i* is expos$ to air & wat]4 ,h5ce !y are frequ5tly ! cause ( mu* tr\ble4 ,9 ! f]m5tative indu/ries !y occasionally cause an improp] sort ( f]m5tation to occur unless c>e is tak5 to prev5t undesir$ species ( bact]ia f be+ pres5t4 ,9 v9eg> mak+1 improp] species ( bact]ia obta9+ access to ! solution give rise to undesirable flav\rs1 greatly injur+ ! product4 ,9 tobacco cur+ x is v common = ! wrong species ( bact]ia to ga9 access to ! tobacco at "s /age ( ! cur+ & by _! gr[? give rise to v>i\s tr\bles4 ,x is ! ubiquit\s pres5ce ( bact]ia :i* makes x impossible to pres]ve fruits1 meats1 or vegetables = any l5g? ( "t )\t special me?ods4 ,?is fact 9 itself has caus$ ! developm5t ( "o ( our mo/ important indu/ries4 ,cann+ meats or fruits consi/s 9 no?+ m ?an br++ !m into a condition 9 :i* !y w be pres]v$ f attack ( ^! micro-organisms4 ,! me?od is extremely simple 9 !ory4 ,x is no?+ m ?an heat+ ! mat]ial to be pres]v$ to a high temp]ature & !n seal+ x h]metically :ile x is /ill hot4 ,! heat kills all ! bact]ia :i* may *ance to be lodg$ 9 x1 & ! h]metical seal+ prev5ts o!r bact]ia f obta9+ access4 ,inasmu* z all organic decomposition is produc$ by bact]ial gr[?1 su* /]iliz$ & seal$ mat]ial w be pres]v$ indef9itely :5 ! op]ation is p]=m$ c>efully en\gh4 ,! me?ods ( accompli%+ ?is ) suffici5t c>e are some:at v>i$ 9 diff]5t indu/ries1 b !y are all fundam5tally ! same4 ,x is an int]e/+ fact t ?is me?od ( pres]v+ meats 0 devis$ 9 ! la/ c5tury1 be=e ! relation ( micro-organisms to f]m5tation & putrefaction 0 really suspect$4 ,= a long "t x _h be5 9 practical use :ile sci5ti/s 7 /ill disput+ :e!r putrefaction c\ld be avoid$ by prev5t+ ! access ( bact]ia4 ,! indu/ry has1 h[ev]1 develop$ wond]fully )9 ! la/ few ye>s1 s9ce ! pr9ciples und]ly+ x h be5 und]/ood4 ,?is und]/&+ has l$ to bett] me?ods ( de/roy+ bact]ial life & to prop] seal+1 & ^! h ( c\rse l$ to great] success 9 ! pres]vation1 until to-day ! cann+ indu/ries are among ^? :i* involve capital reckon$ 9 ! millions4 ,occasionally bact]ia are ( "s value 9 food products4 ,! gamy flav\r ( meats is no?+ m ?an incipi5t decomposition4 ,sau] ,kraut is a food mass int5tionally all[$ to f]m5t & s\r4 ,! value ( bact]ia 9 produc+ butt] & *eese flav\rs is notic$ else:]e4 ,b commonly our aim mu/ be to prev5t ! gr[? ( bact]ia 9 foods4 ,foods mu/ be dri$ or cook$ or kept on ice1 or "s o!r means adopt$ = prev5t+ bact]ial gr[? 9 !m4 ,x is _! pres5ce t =ces u to keep our ice box1 ?us f\nd+ ! ice bus9ess1 z well z t ( ! manufacture ( refrig]ators4 ,x is _! pres5ce1 aga91 t =ces u to smoke hams1 to salt mack]el1 to dry fi% or o!r meats1 to keep pork 9 br9e1 & to introduce num]\s o!r details 9 ! me?ods ( food prep>ation & pres]vation4 ,,*apt] ,,iii4 ,,relation ,,( ,,bact]ia ,,to ,,! ,,dairy ,,indu/ry4 ,dairy+ is "o ( ! mo/ primitive ( our indu/ries4 ,f ! v e>lie/ p]iod1 ev] s9ce man began to keep dome/ic cattle1 he has be5 famili> ) dairy+4 ,dur+ ^! _m c5turies c]ta9 me?ods ( proc$ure h be5 develop$ :i* produce desir$ results4 ,^! me?ods1 h[ev]1 h be5 devis$ simply f ! accumulation ( exp]i5ce1 ) v little k z to ! reasons und]ly+ !m4 ,! me?ods ( pa/ c5turies are1 h[ev]1 ceas+ to be satisfactory4 ,! advance ( our civilization dur+ ! la/ half c5tury has se5 a m>k$ expansion 9 ! ext5t ( ! dairy indu/ry4 ,) ?is expansion has appe>$ ! necessity = new me?ods1 & dairym5 h = ye>s be5 look+ = !m4 ,! la/ few ye>s h be5 tea*+ u t ! new me?ods are to be f\nd along ! l9e ( ! application ( ! discov]ies ( mod]n bact]iology4 ,we h be5 le>n+ t ! dairyman is m closely relat$ to bact]ia & _! activities ?an almo/ any o!r class ( p]sons4 ,mod]n dairy+1 ap>t f ! matt] ( keep+ ! c[1 consi/s l>gely 9 try+ to prev5t bact]ia f gr[+ 9 milk or 9 /imulat+ _! gr[? 9 cream1 butt]1 & *eese4 ,^! *ief products ( ! dairy w be consid]$ sep>ately4 ,,s\rces ,,( ,,bact]ia ,,9 ,,milk4 ,! fir/ fact t claims our att5tion is1 t milk at ! "t x is secret$ f ! udd] ( ! heal?y c[ conta9s no bact]ia4 ,al?\gh bact]ia are almo/ ubiquit\s1 !y are n f\nd 9 ! circulat+ fluids ( heal?y animals1 & are n secret$ by _! gl&s4 ,milk :5 fir/ secret$ by ! milk gl& is !re=e free f bact]ia4 ,x has tak5 a long "t to demon/rate ?is fact1 b x has be5 f9ally satisfactorily prov$4 ,secondly1 x has be5 demon/rat$ t practically all ( ! normal *anges :i* occur 9 milk aft] its secretion are caus$ by ! gr[? ( bact]ia4 ,?is1 too1 0 long d5i$1 & = q a numb] ( ye>s aft] putrefactions & f]m5tations 7 g5]ally ackn[l$g$ to be caus$ by ! gr[? ( micro- organisms1 ! *anges :i* occurr$ 9 milk 7 except$ f ! rule4 ,! uni=mity ) :i* milk w s\r1 & ! difficulty1 or seem+ impossibility1 ( prev5t+ ?is *ange1 l$ to ! belief t ! s\r+ ( milk 0 a normal *ange *>act]i/ic ( milk1 j z clott+ is *>act]i/ic ( blood4 ,?is 01 h[ev]1 ev5tually disprov$1 & x 0 f9ally demon/rat$ t1 beyond a few physical *anges connect$ ) evaporation & a slight oxidation ( ! fat1 milk1 if kept free f bact]ia1 w und]go no *ange4 ,if bact]ia are n pres5t1 x w rema9 sweet indef9itely4 ,b x is impossible to draw milk f ! c[ 9 su* a mann] t x w be free f bact]ia except by ! use ( precautions absolutely impracticable 9 ord9>y dairy+4 ,z milk is commonly drawn1 x is sure to be contam9at$ by bact]ia1 & by ! "t x has ent]$ ! milk pail x conta9s frequ5tly z _m z half a million1 or ev5 a million1 bact]ia 9 e cubic in* ( ! milk4 ,?is seems almo/ incr$ible1 b x has be5 demon/rat$ 9 _m cases & is beyond "q4 ,s9ce ^! bact]ia are n 9 ! secret$ milk1 !y mu/ come f "s ext]nal s\rces1 & ^! s\rces are ! foll[+3 ,! fir/ 9 importance is ! c[ h]self2 = :ile h] milk :5 secret$ is /]ile1 & :ile !re are no bact]ia 9 h] blood1 nev]!less ! c[ is ! mo/ prolific s\rce ( bact]ial contam9ation4 ,9 ! fir/ place1 ! milk ducts are full ( !m4 ,aft] ea* milk+ a little milk is always left 9 ! duct1 & ?is furni%es an ideal place = bact]ia to gr[4 ,"s bact]ia f ! air or else:]e are sure to get into ^! ducts aft] ! milk+1 & !y beg9 at once to multiply rapidly4 ,by ! next milk+ !y become v abundant 9 ! ducts1 & ! fir/ milk drawn wa%es mo/ ( !m at once into ! milk pail1 :]e !y c cont9ue _! gr[? 9 ! milk4 ,aga91 ! ext]ior ( ! c['s body conta9s !m 9 abundance4 ,e hair1 e p>ticle ( dirt1 e bit ( dri$ manure1 is a lurk+ place = millions ( bact]ia4 ,! h9d qu>t]s ( a c[ are commonly 9 a condition ( mu* fil?1 = ! f>m] r>ely grooms 8 c[1 & dur+ ! milk+1 by h] movem5ts1 by ! swit*+ ( h] tail1 & by ! rubb+ %e gets f ! milk]1 no inconsid]able am\nt ( ?is dirt & fil? is bru%$ (f & falls into ! milk pail ,! f>m] und]/&s ?is s\rce ( dirt & usually feels x necess>y to /ra9 ! milk aft] ! milk+4 ,b ! /ra9+ x receives ?r\gh a co>se clo?1 :ile x w remove ! co>s] p>ticles ( dirt1 has no effect ^u ! bact]ia1 = ^! pass ?r\gh any /ra9] unimp$$4 ,aga91 ! milk vessels !mselves conta9 bact]ia1 = !y are nev] wa%$ absolutely clean4 ,aft] ! mo/ ?or\gh wa%+ :i* ! milk pail receives f ! kit*51 !re w always be left _m bact]ia cl++ 9 ! cracks ( ! t9 or 9 ! wood1 ready to beg9 to gr[ z soon z ! milk once m fills ! pail ,! milk] himself contributes to ! supply1 = he goes to ! milk+ ) unclean h&s1 unclean clo!s1 & n a few bact]ia get f him to 8 milk pail4 ,la/ly1 we f9d ! air ( ! milk+ /all furni%+ its quota ( milk bact]ia4 ,?is s\rce ( bact]ia is1 h[ ev]1 n s great z 0 =m]ly believ$4 ,t ! air may conta9 _m bact]ia 9 its du/ is c]ta91 & d\btless ^! fall 9 "s quantity into ! milk1 especially if ! cattle are all[$ to fe$ ^u du/y hay be=e & dur+ ! milk+4 ,b unless ! air is ?us full ( du/ ?is s\rce ( bact]ia is n v great1 & comp>$ ) ! bact]ia f ! o!r s\rces ! air bact]ia are unimportant4 ,! milk ?us gets fill$ ) bact]ia1 & s9ce x furni%es an excell5t food ^! bact]ia beg9 at once to gr[4 ,! milk :5 drawn is w>m & at a temp]ature :i* especially /imulates bact]ial gr[?4 ,!y multiply ) great rapidity1 & 9 ! c\rse ( a few h\rs increase p]haps a ?\s&fold4 ,! numb]s :i* may be f\nd aft] tw5ty-f\r h\rs are sometimes inconceivable2 m>ket milk may conta9 z _m z five hundr$ millions p] cubic in*2 & :ile ?is is a decid$ly extreme numb]1 milk t is a day old w almo/ always conta9 _m millions 9 ea* cubic in*1 ! numb] dep5d+ ^u ! age ( ! milk & its temp]ature4 ,dur+ ?is gr[? ! bact]ia h1 ( c\rse1 n be5 )\t _! effect4 ,recognis+ z we d t bact]ia are ag5ts = *emical *ange1 we are prep>$ to see ! milk und]go+ "s modifications dur+ ?is rapid multiplication ( bact]ia4 ,! *anges :i* ^! bact]ia produce 9 ! milk & its products are num]\s1 & decid$ly affect its value4 ,!y are bo? advantage\s & disadvantage\s to ! dairyman4 ,!y are nuisances s f> z conc]ns ! milk produc]1 b allies ( ! butt] & *eese mak]4 ,,! ,,effect ,,( ,,bact]ia ,,on ,,milk4 ,! fir/ & mo/ univ]sal *ange effect$ 9 milk is its ,,s\r+4 ,s univ]sal is ?is ph5om5on t x is g5]ally reg>d$ z an inevitable *ange :i* c n be avoid$1 &1 z already po9t$ out1 has 9 ! pa/ be5 reg>d$ z a normal prop]ty ( milk4 ,to-day1 h[ev]1 ! ph5om5on is well und]/ood4 ,x is due to ! action ( c]ta9 ( ! milk bact]ia ^u ! milk sug> :i* conv]ts x into lactic acid1 & ?is acid gives ! s\r ta/e & curdles ! milk4 ,aft] ?is acid is produc$ 9 small quantity its pres5ce proves delet]i\s to ! gr[? ( ! bact]ia1 & fur!r bact]ial gr[? is *eck$4 ,aft] s\r+1 !re=e1 ! milk = "s "t does n ord9>ily und]go any fur!r *anges4 ,milk s\r+ has be5 commonly reg>d$ z a s+le ph5om5on1 alike 9 all cases4 ,:5 x 0 fir/ /udi$ by bact]iologi/s x 0 ?\ght to be due 9 all cases to a s+le species ( micro-organism :i* 0 discov]$ to be commonly pres5t & nam$ ,bacillus acidi lactici 7,fig4 #ai74 ,?is bact]ium has c]ta9ly ! p[] ( s\r+ milk rapidly1 & is f\nd to be v common 9 dairies 9 ,europe4 ,z soon z bact]iologi/s turn$ _! att5tion m closely to ! subject x 0 f\nd t ! spontane\s s\r+ ( milk 0 n always caus$ by ! same species ( bact]ium4 ,in/ead ( f9d+ ?is ,bacillus acidi lactici always pres5t1 !y f\nd t q a numb] ( diff]5t species ( bact]ia h ! p[] ( s\r+ milk1 & are f\nd 9 diff]5t specim5s ( s\r$ milk4 ,! numb] ( species ( bact]ia :i* h be5 f\nd to s\r milk has increas$ until some?+ ov] a hundr$ are kn[n to h ?is p[]4 ,^! diff]5t species d n affect ! milk 9 ! same way4 ,all produce "s acid1 b !y diff] 9 ! k9d & ! am\nt ( acid1 & especially 9 ! o!r *anges :i* are effect$ at ! same "t t ! milk is s\r$1 s t ! result+ s\r$ milk is q v>iable4 ,9 spite ( ?is v>iety1 h[ev]1 ! mo/ rec5t "w t5ds to %[ t ! majority ( cases ( spontane\s s\r+ ( milk are produc$ by bact]ia :i*1 ?\gh some:at v>iable1 probably con/itute a s+le species1 & are id5tical ) ! ,bacillus acidi lactici 7,fig4 #ai74 ,?is species1 f\nd common 9 ! dairies ( ,europe1 accord+ to rec5t inve/igations occurs 9 ?is c\ntry z well4 ,we may say1 !n1 t :ile !re are _m species ( bact]ia infe/+ ! dairy :i* c s\r ! milk1 !re is "o :i* is m common & m univ]sally f\nd ?an o!rs1 & ?is is ! ord9>y cause ( milk s\r+4 ,:5 we /udy m c>efully ! effect ^u ! milk ( ! diff]5t species ( bact]ia f\nd 9 ! dairy1 we f9d t !re is a great v>iety ( *anges :i* !y produce :5 !y are all[$ to gr[ 9 milk4 ,! dairyman exp]i5ces _m tr\bles ) 8 milk4 ,x sometimes curdles )\t becom+ acid4 ,sometimes x becomes bitt]1 or acquires an unpleasant ta9t$ ta/e1 or1 aga91 a soapy ta/e4 ,occasionally a dairyman f9ds 8 milk becom+ slimy1 in/ead ( s\r+ & curdl+ 9 ! normal fa%ion4 ,at su* times1 aft] a numb] ( h\rs1 ! milk becomes s slimy t x c be drawn into long ?reads4 ,su* an infection proves v tr\blesome1 = _m a "t x p]si/s 9 spite ( all attempts made to rem$y x4 ,aga91 9 o!r cases ! milk w turn blue1 acquir+ ab\t ! "t x becomes s\r a beautiful sky-blue col\r4 ,or x may become r$1 or occasionally yell[4 ,all ( ^! tr\bles ! dairyman owes to ! pres5ce 9 8 milk ( unusual species ( bact]ia :i* gr[ !re abundantly4 ,bact]iologi/s h be5 able to make out satisfactorily ! connection ( all ^! infections ) diff]5t species ( ! bact]ia4 ,a l>ge numb] ( species h be5 f\nd to curdle milk )\t r5d]+ x acid1 sev]al r5d] x bitt]1 & a numb] produce a ta9t$ & "o a soapy ta/e4 ,a score or m h be5 f\nd :i* h ! p[] ( r5d]+ ! milk slimy4 ,two diff]5t species at lea/ h ! p[] ( turn+ ! milk to sky-blue col\r2 two or ?ree produce r$ pigm5ts 7,fig4 #bj71 & "o or two h be5 f\nd :i* produce a yell[ col\r4 ,9 %ort1 x has be5 det]m9$ beyond "q t all ^! infections1 :i* are m or less tr\blesome to dairym51 are due to ! gr[? ( unusual bact]ia 9 ! milk4 ,^! v>i\s infections are all tr\blesome1 & inde$ x may be said t1 s f> z conc]ns ! milk produc] & ! milk consum]1 bact]ia are f beg9n+ to end a s\rce ( tr\ble4 ,x is ! desire ( ! milk produc] to avoid !m z f> z possible--a desire :i* is %>$ also by ev]yone :o has any?+ to d ) milk z milk4 ,hav+ recognis$ t ! v>i\s tr\bles1 :i* occasionally occur ev5 9 ! bett] class ( dairies1 are due to bact]ia1 ! dairyman is1 at lea/ 9 a measure1 prep>$ to avoid !m4 ,! avoid+ ( ^! tr\bles is mod]ately easy z soon z dairym5 recognise ! s\rce f :i* ! infecti\s organisms come1 & also ! fact t l[ temp]atures w 9 all cases rem$y ! evil to a l>ge ext5t4 ,) ?is k 9 h& ! avoidance ( all ^! tr\bles is only a "q ( c>e 9 h&l+ ! dairy4 ,x mu/ be recognis$ t mo/ ( ^! tr\blesome bact]ia come f "s unusual s\rces ( infection4 ,by unusual s\rces are meant ^? :i* ! ex]cise ( c>e w avoid4 ,x is true t ! s\r+ bact]ia appe> to be s univ]sally di/ribut$ t !y c n be avoid$ by any ord9>y means4 ,b all o!r tr\blesome bact]ia appe> to be )9 control4 ,! milkman mu/ rememb] t ! s\rces ( ! tr\bles :i* are liable to arise 9 8 milk are 9 "s =m ( fil?3 ei!r fil? on ! c[1 or du/ 9 ! hay :i* is scatt]$ ?r\gh ! b>n1 or dirt on c[s' udd]s1 or "s o!r unusual & avoidable s\rce4 ,^! s\rces1 f :at we h already notic$1 w always furni% ! milk ) bact]ia2 b "u common conditions1 & :5 ! c[ is kept 9 conditions ( ord9>y cleanl9ess1 & frequ5tly ev5 :5 n cleanly1 w only furni% bact]ia t produce ! univ]sal s\r+4 ,recognis+ ?is1 ! dairyman at once le>ns t 8 rem$ies = ! tr\blesome infections are cleanl9ess & l[ temp]atures4 ,if he is c>eful to keep 8 milk vessels scrupul\sly clean2 if he w keep 8 c[ z cleanly z he does 8 horse2 & if he w use c>e 9 & ar\nd ! b>n & dairy1 & !n apply l[ temp]atures to ! milk1 he ne$ nev] be di/urb$ by slimy or ta9t$ milk1 or any ( ^! o!r tr\bles2 or he c remove su* infections spe$ily %\ld !y once appe>4 ,pure sweet milk is only a "q ( suffici5t c>e4 ,b c>e means lab\r & exp5se4 ,z long z we dem& *eap milk1 s long w we be suppli$ ) milk procur$ "u conditions ( fil?4 ,b :5 we le>n t *eap milk is poor milk1 & :5 we are will+ to pay a little m = x1 !n only may we expect ! use ( great] c>e 9 ! h&l+ ( ! milk1 result+ 9 a pur] product4 ,bact]iology has !re=e taught u t ! :ole "q ( ! milk supply 9 our communities is "o ( avoid+ ! too rapid gr[? ( bact]ia4 ,^! organisms are uni=mly a nuisance to ! milkman4 ,to avoid _! evil influ5ce h be5 design$ all ! me?ods ( c>+ = ! dairy & ! b>n1 all ! me?ods ( di/ribut+ milk 9 ice c>s4 ,moreov]1 all ! special devices connect$ ) ! great indu/ry ( milk supply h = _! f\ndation ! attempt to avoid1 9 ! fir/ place1 ! pres5ce ( too great a numb] ( bact]ia1 &4 9 ! second place1 ! gr[? ( ^! bact]ia4 ,,bact]ia ,,9 ,,butt] ,,mak+4 ,,cream ,,rip5+4--,pass+ f milk to butt]1 we f9d a some:at diff]5t /ory1 inasmu* z "h bact]ia are direct allies to ! dairyman r ?an 8 enemies4 ,)\t be+ aw>e ( x1 butt] mak]s h = ye>s be5 mak+ use ( bact]ia 9 _! butt] mak+ & h be5 pr(it+ by ! products :i* ! bact]ia h furni%$ !m4 ,cream1 z x is obta9$ f milk1 w always conta9 bact]ia 9 l>ge quantity1 & ^! bact]ia w gr[ z readily 9 ! cream z !y w 9 ! milk4 ,! butt] mak] seldom *urns 8 cream :5 x is fre%ly obta9$ f ! milk4 ,!re are1 x is true1 "s places :]e sweet cream butt] is made & is 9 dem&1 b 9 ! majority ( butt]-consum+ c\ntries a diff]5t quality ( butt] is desir$1 & ! cream is subject$ to a process kn[n z rip5+ or s\r+ be=e x is *urn$4 ,9 rip5+1 ! cream is simply all[$ to /& 9 a vat = a p]iod v>y+ f twelve h\rs to two or ?ree days1 accord+ to circum/ances4 ,dur+ ?is p]iod c]ta9 *anges take place !re94 ,! bact]ia :i* 7 9 ! cream orig9ally1 get an opportunity to gr[1 & by ! "t ! rip5+ is complete !y become extremely num]\s4 ,z a result1 ! "* ( ! cream *anges j z ! milk is *ang$ "u simil> circum/ances4 ,x becomes some:at s\r$2 x becomes slightly curdl$1 & acquires a peculi>ly pleasant ta/e & an aroma :i* 0 n pres5t 9 ! orig9al fre% cream4 ,aft] ?is rip5+ ! cream is *urn$4 ,x is dur+ ! rip5+ t ! bact]ia produce _! effect1 = aft] ! *urn+ !y are ( less importance4 ,"p ( !m collect 9 ! butt]1 "p ( !m are wa%$ (f f ! butt] 9 ! butt]milk & ! subsequ5t processes4 ,mo/ ( ! bact]ia t are left 9 ! butt] soon die1 n f9d+ !re a fav\rable condition = gr[?2 "s ( !m1 h[ev]1 live & gr[ = "s "t & are prom95t ag5ts 9 ! *anges by :i* butt] becomes rancid4 ,! butt] mak] is conc]n$ ) ! rip5+ r ?an ) lat] processes4 ,! object ( ! rip5+ ( cream is to r5d] x 9 a bett] condition = butt] mak+4 ,! butt] mak] has le>n$ by long- exp]i5ce t rip5$ cream *urns m rapidly ?an sweet cream1 & t he obta9s a l>g] yield ( butt] !refrom4 ,! great object ( ! rip5+1 h[ev]1 is to develop 9 ! butt] ! peculi> flav\r & aroma :i* is *>act]i/ic ( ! highe/ product4 ,sweet cream butt] lacks flav\r & aroma1 hav+ inde$ a ta/e almo/ id5tically ! same z cream4 ,butt]1 h[ev]1 t is made f rip5$ cream has a peculi> delicate flav\r & aroma :i* is well kn[n to lov]s ( butt]1 & :i* is develop$ dur+ ! rip5+ process4 ,bact]iologi/s h be5 able to expla9 ) a consid]able degree ( accuracy ! object ( ?is rip5+4 ,! process is really a f]m5tation comp>able to ! f]m5tation t takes place 9 a brew]'s malt4 ,! gr[? ( bact]ia dur+ ! rip5+ produces *emical *anges ( a some:at complicat$ "*1 & conc]ns ea* ( ! +r$i5ts ( ! milk4 ,! lactic-acid organisms affect ! milk sug> & produce lactic acid2 o!rs act ^u ! fat1 produc+ slight *anges !re92 :ile o!rs act ^u ! case9 & ! album5s ( ! milk4 ,z a result1 v>i\s biproducts ( decomposition arise1 & x is ^! biproducts ( decomposition t make ! diff]5ce betwe5 ! rip5$ & ! unrip5$ cream4 ,!y r5d] x s\r & curdle x1 & !y also produce ! flav\rs & aromas t *>act]ize x4 ,products ( decomposition are g5]ally look$ ^u z undesirable = food1 & ?is is equally true ( ^! products t arise 9 cream if ! decomposition is all[$ to cont9ue long en\gh4 ,if ! rip5+1 in/ead ( be+ /opp$ at ! end ( a day or two1 is all[$ to cont9ue sev]al days1 ! cream becomes decay$ & ! butt] made !refrom is decid$ly (f5sive4 ,b "u ! conditions ( ord9>y rip5+1 :5 ! process is /opp$ at ! "r mom5t1 ! decomposition products are pleasant r ?an unpleasant1 & ! flav\rs & aromas :i* !y imp>t to ! cream & to ! subsequ5t butt] are ^? t are desir$4 ,x is ^! decomposition products t give ! peculi> "* to a high quality ( butt]1 & ?is peculi> quality is a matt] t det]m9es ! price :i* ! butt] mak] c obta9 = 8 product4 ,b1 un=tunately1 ! butt] mak] is n always able to dep5d ^u ! rip5+4 ,:ile commonly x progresses 9 a satisfactory mann]1 sometimes1 = no reason t he c assign1 ! rip5+ does n progress normally4 ,in/ead ( develop+ ! pleasant aroma & flav\r ( ! prop]ly rip5$ cream1 ! cream develops unpleasant ta/es4 ,x may be bitt] or some:at ta9t$1 & j z sure z ^! flav\rs develop 9 ! cream1 s sure does ! quality ( ! butt] suff]4 ,moreov]1 x has be5 le>n$ by exp]i5ce t "s cream]ies are incapable ( obta9+ an equally good rip5+ ( _! cream4 ,:ile "s ( !m w obta9 fav\rable results1 o!rs1 ) equal c>e1 w obta9 a f> less fav\rable flav\r & aroma 9 _! butt]4 ,! reason = all ?is has be5 expla9$ by mod]n bact]iology4 ,9 ! milk1 & consequ5tly 9 ! cream1 !re are always f\nd _m bact]ia1 b ^! are n always ( ! same k9ds4 ,!re are scores1 & probably hundr$s1 ( species ( bact]ia common 9 & ar\nd our b>ns & dairies1 & ! bact]ia t are abundant & t gr[ 9 diff]5t lots ( cream w n be always ! same4 ,x makes a decid$ diff]5ce 9 ! "* ( ! rip5+1 & 9 ! consequ5t flav\rs & aromas1 :e!r "o or ano!r species ( bact]ia has be5 gr[+ 9 ! cream4 ,"s species are f\nd to produce good results ) desir$ flav\rs1 :ile o!rs1 "u id5tical conditions1 produce decid$ly poor results ) undesir$ flav\rs4 ,if ! butt] mak] obta9s cream :i* is fill$ ) a l>ge numb] ( bact]ia capable ( produc+ good flav\rs1 !n ! rip5+ ( 8 cream w be satisfactory & 8 butt] w be ( high quality4 ,if1 h[ev]1 x *ances t 8 cream conta9s only ! species :i* produce unpleasant flav\rs1 !n ! "* ( ! rip5+ w be decid$ly inf]ior & ! butt] w be ( a poor] grade4 ,=tunately ! majority ( ! k9ds ( bact]ia liable to get into ! cream f ord9>y s\rces are su* z produce ei!r good effects ^u ! cream or d n mat]ially influ5ce ! flav\r or aroma4 ,h5ce x is t ! rip5+ ( cream w commonly produce good results4 ,bact]iologi/s h le>n$ t !re are "s species ( bact]ia m or less common ar\nd our b>ns :i* produce undesirable effects ^u flav\r1 & %\ld ^! become especially abundant 9 ! cream1 !n ! "* ( ! rip5+ & ! quality ( ! subsequ5t butt] w suff]4 ,^! malign species ( bact]ia1 h[ev]1 are n v common 9 prop]ly kept b>ns & dairies4 ,h5ce ! process t is s widely us$1 ( simply all[+ cream to rip5 "u ! influ5ce ( any bact]ia t happ5 to be 9 x1 ord9>ily produces good results4 ,b our butt] mak]s sometimes f9d1 at ! times :5 ! cattle *ange f w9t] to summ] or f summ] to w9t] fe$1 t ! rip5+ is abnormal4 ,! reason appe>s to be t ! cream has become infe/$ ) an abundance ( malign species4 ,! rip5+ t !y produce is !re=e an undesirable "o1 & ! quality ( ! butt] is sure to suff]4 ,s long z butt] 0 made only 9 private dairies x 0 a matt] ( comp>atively little importance if !re 0 an occasional fall+ (f 9 quality ( ?is sort4 ,:5 x 0 made a few p\nds at a "t1 & only once or twice a week1 x 0 n a v s]i\s matt] if a few *urn+s ( butt] did suff] 9 quality4 ,b to-day ! butt]-mak+ indu/ries are becom+ m & m conc5trat$ into l>ge cream]ies1 & x is a matt] ( a good deal m importance to discov] "s means by :i* a uni=mly high quality c be insur$4 ,if a cream]y :i* makes five hundr$ p\nds ( butt] p] day suff]s f su* an injuri\s rip5+1 ! quality ( its butt] w fall (f to su* an ext5t z to comm& a l[] price1 & ! cream]y suff]s mat]ially4 ,p]haps ! cont9uation ( su* a tr\ble = two or ?ree weeks w\ld make a diff]5ce betwe5 f9ancial success & failure 9 ! cream]y4 ,) our conc5tration ( ! butt]- mak+ indu/ries x is becom+ ?us desirable to discov] "s means ( regulat+ ?is process m accurately4 ,! rem$y ( ^! occasional ill effects 9 cream rip5+ has n be5 )9 ! rea* ( ! butt] mak]4 ,! butt] mak] mu/ make butt] ) ! cream t is furni%$ him1 & if t cream is already impregnat$ ) malign species ( bact]ia he is helpless4 ,x is true t mu* c be done to rem$y ^! difficulties by ! ex]cise ( especial c>e 9 ! b>ns ( ! patrons ( ! cream]y4 ,if ! b>ns1 ! c[s1 ! dairies1 ! milk vessels1 etc41 are all kept 9 condition ( /rict cleanl9ess1 if especial c>e is tak5 p>ticul>ly at ! seasons ( ! ye> :5 tr\ble is likely to arise1 & if "s att5tion is paid to ! k9d ( food :i* ! cattle eat1 z a rule ! cream w n become infect$ ) injuri\s bact]ia4 ,x may be tak5 z a demon/rat$ fact t ^! malign bact]ia come f s\rces ( fil?1 & ! c>eful avoidance ( all su* s\rces ( fil? w 9 a v l>ge measure prev5t _! occurr5ce 9 ! cream4 ,su* measures z ^! h be5 f\nd to be practicable 9 _m cream]ies4 ,cream]ies :i* make ! highe/ pric$ & ! mo/ uni=m quality ( butt] are ^? 9 :i* ! greate/ c>e is tak5 9 ! b>ns & dairies to insure cleanl9ess & 9 ! h&l+ ( ! milk & cream4 ,) su* att5tion a l>ge portion ( ! tr\ble :i* arises 9 ! cream]ies f malign bact]ia may be avoid$4 ,b ^! me?ods furni% no sure rem$y aga9/ evils ( improp] species ( bact]ia 9 cream rip5+1 & d n furni% any sure means ( obta9+ uni=m flav\r 9 butt]4 ,ev5 "u ! v be/ conditions ! flav\r ( ! butt] w v>y ) ! season ( ! ye>4 ,butt] made 9 ! w9t] is inf]ior to t made 9 ! summ] mon?s2 & :ile ?is is d\btless due 9 "p to ! diff]5t food :i* ! cattle h & to ! "* ( ! cream result+ !refrom1 ^! diff]5ces 9 ! flav\r ( ! butt] are also 9 "p dep5d5t ^u ! diff]5t species ( bact]ia :i* are pres5t 9 ! rip5+ ( cream at diff]5t seasons4 ,! species ( bact]ia 9 ,june cream are diff]5t f ^? t are commonly pres5t 9 ,janu>y cream1 & ?is is c]ta9ly a factor 9 det]m9+ ! diff]5ce betwe5 w9t] & summ] butt]4 ,,use ,,( ,,artificial ,,bact]ia ,,cultures ,,= ,,cream ,,rip5+4 ,bact]iologi/s h be5 = "s "t endeav\r+ to aid butt] mak]s 9 ?is direction by furni%+ !m ) ! bact]ia ne$ful = ! be/ results 9 cream rip5+4 ,! me?od ( do+ ?is is extremely simple 9 pr9ciple1 b proves to be some:at difficult 9 practice4 ,x is only necess>y to obta9 ! species ( bact]ia t produce ! highe/ results1 & !n to furni% ^! 9 pure culture & 9 l>ge quantity to ! butt] mak]s1 to enable !m to inoculate _! cream ) ! species ( bact]ia :i* w produce ! results t !y desire4 ,= ?is purpose bact]iologi/s h be5 = sev]al ye>s se>*+ = ! prop] species ( bact]ia to produce ! be/ results1 & !re h be5 put ^u ! m>ket = sale sev]al di/9ct pure cultures = ?is purpose4 ,^! h be5 obta9$ by diff]5t bact]iologi/s & dairym5 9 ! nor!rn ,european c\ntries & also 9 ! ,unit$ ,/ates4 ,^! pure cultures are furni%$ to ! dairym5 9 v>i\s =ms1 b !y always consi/ ( great quantities ( c]ta9 k9ds ( bact]ia :i* exp]i5ce has f\nd to be advantage\s = ! purpose ( cream rip5+4 ,!re h hi!rto appe>$ a numb] ( difficulties 9 ! way ( rea*+ complete success 9 ^! directions4 ,! mo/ prom95t arises 9 devis+ a me?od ( us+ pure cultures 9 ! cream]y4 ,! cream :i* ! butt] mak]s desire to rip5 is1 z we h se51 already impregnat$ ) bact]ia1 & w\ld rip5 9 a fa%ion ( its own ev5 if no pure culture ( bact]ia 7 add$ !reto4 ,pure cultures c n !re=e be us$ z simply z c yea/ 9 bread d\gh4 ,x is pla9 t ! simple addition ( a pure culture to a mass ( cream w\ld n produce ! desir$ effects1 because ! cream w\ld be rip5$ !n1 n by ! pure culture alone1 b by ! pure culture plus all ( ! bact]ia t 7 orig9ally pres5t4 ,x w\ld1 ( c\rse1 be some?+ ( a "q z to :e!r "u ^! conditions ! results w\ld be fav\rable1 & x w\ld seem t ?is me?od w\ld n furni% any means ( gett+ rid ( bad ta/es & flav\rs :i* h come f ! pres5ce ( malign species ( bact]ia4 ,x is pla9ly desirable to get rid ( ! cream bact]ia be=e ! pure culture is add$4 ,?is c be readily done by heat+ x to a temp]ature ( #fi degrees ,c4 7#aee degrees ,f47 = a %ort "t1 ?is temp]ature be+ suffici5t to de/roy mo/ ( ! bact]ia4 ,! subsequ5t addition ( ! pure culture ( cream-rip5+ bact]ia w cause ! cream to rip5 "u ! influ5ce ( ! add$ culture alone4 ,?is me?od proves to be successful1 & 9 ! butt] mak+ c\ntries 9 ,europe x is becom+ rapidly adopt$4 ,9 ?is c\ntry1 h[ev]1 ?is process has n z yet become v popul>1 inasmu* z ! heat+ ( ! cream is a matt] ( consid]able exp5se & tr\ble1 & our butt] mak]s h n be5 v ready to adopt x4 ,= ?is reason1 & also = ! purpose ( famili>iz+ butt] mak]s ) ! use ( pure cultures1 x has be5 attempt$ to produce some:at simil> ?\gh less uni=m results by ! use ( pure cultures 9 cream )\t previ\s heal+4 ,9 ! use ( pure cultures 9 ?is way1 ! butt] mak] is direct$ to add to 8 cream a l>ge am\nt ( a prep>$ culture ( c]ta9 species ( bact]ia1 ^u ! pr9ciple t ! addition ( su* a l>ge numb] ( bact]ia to ! cream1 ev5 ?\gh ! cream is already inoculat$ ) c]ta9 bact]ia1 w produce a rip5+ ( ! cream *iefly influ5c$ by ! artificially add$ culture4 ,! culture ?us add$1 be+ pres5t 9 v mu* great] quantity ?an ! o!r wild species1 w h a mu* great] effect ?an any ( !m4 ,?is me?od1 ( c\rse1 _c insure uni=mity4 ,:ile x may "w satisfactorily 9 _m cases1 x is v evid5t t 9 o!rs1 :5 ! cream is already fill$ ) a l>ge numb] ( malign species ( bact]ia1 su* an artificial culture w\ld n produce ! desir$ results4 ,?is appe>s to be n only ! !oretical b ! actual exp]i5ce4 ,! addition ( su* pure cultures 9 _m cases produces fav\rable results1 b x does n always d s1 & ! result is n uni=m4 ,:ile ! use ( pure cultures 9 ?is way is an advantage ov] ! me?od ( simply all[+ ! cream to rip5 normally )\t su* additions1 x is a me?od t is decid$ly inf]ior to t :i* fir/ pa/eurizes ! cream & subsequ5tly adds a />t]4 ,!re is /ill ano!r me?od ( add+ bact]ia to cream to insure a m advantage\s rip5+1 :i* is frequ5tly us$1 &1 be+ simpl]1 is 9 _m cases a decid$ advantage4 ,?is me?od is by ! use ( :at is call$ a natural />t]4 ,a natural />t] consi/s simply ( a lot ( cream :i* has be5 tak5 f ! mo/ fav\rable s\rce possible--t is1 f ! cleane/ & be/ dairy1 or f ! h]d produc+ ! be/ quality ( cream--& all[+ ?is cream to /& 9 a w>m place = a c\ple ( days until x becomes s\r4 ,! cream w by t "t be fill$ ) l>ge numb]s ( bact]ia1 & ?is is !n put z a />t] into ! vat ( cream to be rip5$4 ,( c\rse1 9 ! use ( ?is me?od ! butt] mak] has no control ov] ! k9ds ( bact]ia t w gr[ 9 ! />t]1 b x is f\nd1 practically1 t if ! cream is tak5 f a good s\rce ! results are extremely fav\rable1 & !re is produc$ 9 ?is way almo/ always an improvem5t 9 ! butt]4 ,! use ( pure cultures is /ill q new1 p>ticul>ly 9 ?is c\ntry4 ,9 ! ,european butt]-mak+ c\ntries !y h be5 us$ = a long] p]iod & h become v mu* bett] kn[n4 ,:at ! future may develop along ?is l9e x is difficult to say2 b x seems at lea/ probable t z ! difficulties 9 ! details are ma/]$ ! "t w come :5 />t]s w be us$ by our butt] mak]s = _! cream rip5+1 j z yea/ is us$ by h\sewives = rais+ bread1 or by brew]s = f]m5t+ malt4 ,^! />t]s w probably 9 "t be furni%$ by bact]iologi/s4 ,bact]iology1 9 o!r words1 is (f]+ 9 ! ne> future to our butt] mak]s a me?od ( controll+ ! rip5+ ( ! cream 9 su* a way z to insure ! obta9+ ( a high & uni=m quality ( butt]1 s f>1 at lea/1 z conc]ns flav\r & aroma4 ,,bact]ia ,,9 ,,*eese4 ,*eese rip5+4--,! ?ird great product ( ! dairy indu/ry is *eese1 & 9 connection ) ?is product ! dairyman is ev5 m dep5d5t ^u bact]ia ?an he is 9 ! production ( butt]4 ,9 ! manufacture ( *eese ! case9 ( ! milk is sep>at$ f ! o!r products by ! use ( r5net1 & is collect$ 9 l>ge masses & press$1 =m+ ! fre% *eese4 ,?is *eese is !n set aside = sev]al weeks1 & sometimes = mon?s1 to und]go a process t is kn[n z rip5+4 ,dur+ ! rip5+ !re are develop$ 9 ! *eese ! peculi> flav\rs :i* are *>act]i/ic ( ! complet$ product4 ,! ta/e ( fre%ly made *eese is extremely unlike t ( ! rip5$ product4 ,:ile butt] made f unrip5$ cream has a pleasant flav\r1 & "o :i* is 9 _m places p>ticul>ly enjoy$1 !re is n[h]e a dem& = unrip5$ *eese1 = ! fre%ly made *eese has a ta/e t sc>ce any "o reg>ds z pleasant4 ,inde$1 ! :ole value ( ! *eese is dep5d5t ^u ! flav\r ( ! product1 & ?is flav\r is develop$ dur+ ! rip5+4 ,! *eese mak] f9ds 9 ! rip5+ ( 8 *eese ! mo/ difficult "p ( 8 manufacture4 ,x is inde$ a process ov] :i* he has v little control4 ,ev5 :5 all conditions seem to be correct1 :5 *eese is made 9 ! mo/ c>eful mann]1 x n infrequ5tly occurs t ! rip5+ takes place 9 a mann] t is entirely abnormal1 & ! result+ *eese becomes wor?less4 ,! *eese mak] has be5 at an entire loss to und]/& ^! irregul>ities1 nor has he possess$ any means ( remov+ !m4 ,! abnormal rip5+ t occurs takes on v>i\s types4 ,sometimes ! *eese w become extraord9>ily por\s1 fill$ ) l>ge holes :i* cause ! *eese to swell out ( prop] %ape & become wor?less4 ,at o!r times v>i\s spots ( r$ or blue appe> 9 ! manufactur$ *eese2 :ile aga9 unpleasant ta/es & flav\rs develop :i* r5d] ! product ( no value4 ,sometimes a consid]able portion ( ! product ( ! *eese factory und]goes su* irregul> rip5+1 & ! product = a long "t w ?us be wor?less4 ,if "s means c\ld be discov]$ ( remov+ ^! irregul>ities x w\ld be a great boon to ! *eese manufactur]2 & v _m attempts h be5 made 9 "o way or ano!r to furni% ! *eese mak] ) "s details 9 ! manufacture :i* w enable him 9 a measure to control ! rip5+4 ,! rip5+ ( ! *eese has be5 subject$ to a l>ge am\nt ( /udy on ! "p ( bact]iologi/s :o h be5 int]e/$ 9 dairy products4 ,t ! rip5+ ( *eese is ! result ( bact]ial gr[? !re9 appe>s to be probable f a priori gr\nds4 ,l ! rip5+ ( cream1 x is a process t occurs some:at sl[ly4 ,x is a *emical *ange :i* is accompani$ by ! de/ruction ( proteid matt]2 x takes place be/ at c]ta9 temp]atures1 & temp]atures :i* we "k are fav\rable to ! gr[? ( micro-organisms1 all ( :i* ph5om5a sugge/ to u ! action ( bact]ia4 ,moreov]1 ! flav\rs & ! ta/es t arise h a decid$ resemblance 9 _m cases to ! decomposition products ( bact]ia1 /rik+ly s 9 ,limburg] *eese4 ,:5 we come to /udy ! matt] ( *eese rip5+ c>efully we le>n beyond "q t ?is a priori conclusion is correct4 ,! rip5+ ( any *eese is dep5d5t ^u sev]al diff]5t factors4 ,! me?od ( prep>ation1 ! am\nt ( wat] left 9 ! curd1 ! temp]ature ( rip5+1 & o!r miscellane\s factors connect$ ) ! me*anical process ( *eese manufacture1 affect its "*4 ,b1 9 addition to all ^! factors1 !re is und\bt$ly ano!r "o1 & t is ! numb] & ! "* ( ! bact]ia t *ance to be 9 ! curd :5 ! *eese is made4 ,:ile x is f\nd t *eeses :i* are treat$ by diff]5t processes w rip5 9 a diff]5t mann]1 x is also f\nd t two *eeses :i* h be5 made "u simil> conditions & treat$ 9 id5tically ! same way may also rip5 9 a diff]5t mann]1 s t ! result+ flav\r w v>y4 ,! v>iations betwe5 *eeses ?us made may be slight or !y may be consid]able1 b v>iations c]ta9ly d occur4 ,e "o kn[s ! great diff]5ce 9 flav\rs ( diff]5t *eeses1 & ^! flav\rs are due 9 consid]able measure to factors o!r ?an ! simple me*anical process ( mak+ ! *eese4 ,! g5]al simil>ity ( ! :ole process to a bact]ial f]m5tation leads u to believe at ! outset t "s ( ! diff]5ces 9 "* are due to diff]5t k9ds ( bact]ia t multiply 9 ! *eese & produce decomposition !re94 ,:5 ! matt] comes to be /udi$ by bact]iology1 ! demon/ration ( ?is position becomes easy4 ,t ! rip5+ ( *eese is due to gr[? ( bact]ia is v easily prov$ by manufactur+ *eeses f milk :i* is depriv$ ( bact]ia4 ,= in/ance1 *eeses h be5 made f milk t has be5 ei!r /]iliz$ or pa/euriz$--:i* processes de/roy mo/ ( ! bact]ia !re9--&1 treat$ o!rwise 9 a normal mann]1 are set aside to rip54 ,^! *eeses d ,,n rip51 b rema9 = mon?s ) practically ! same ta/e t !y _h orig9ally4 ,9 o!r exp]im5ts ! *eese has be5 treat$ ) a small am\nt ( dis9fective1 :i* is suffici5t to prev5t bact]ia f gr[+1 & aga9 rip5+ is f\nd to be absolutely prev5t$4 ,fur!rmore1 if ! *eese "u ord9>y conditions is /udi$ dur+ ! rip5+ process1 x is f\nd t bact]ia are gr[+ dur+ ! :ole "t4 ,^! facts all tak5 toge!r pla9ly prove t ! rip5+ ( *eese is a f]m5tation due to bact]ia4 ,x w be notic$1 h[ev]1 t ! conditions 9 ! *eese are n fav\rable = v rapid bact]ial gr[?4 ,x is true t !re is pl5ty ( food 9 ! *eese = bact]ial life1 b ! *eese is n v moi/2 x is extremely d5se1 be+ subject$ 9 all cases to m or less pressure4 ,! p5etration ( oxyg5 into ! c5tre ( ! mass mu/ be extremely slight4 ,! d5sity1 ! lack ( a great am\nt ( moi/ure1 & ! lack ( oxyg5 furni% conditions 9 :i* bact]ia w n gr[ v rapidly4 ,! conditions are f> less fav\rable ?an ^? ( rip5+ cream1 & ! bact]ia d n gr[ ) any?+ l ! rapidity t !y gr[ 9 cream4 ,inde$1 ! gr[? ( ^! organisms dur+ ! rip5+ is extremely sl[ comp>$ to ! possibilities ( bact]ial gr[? t we h already notic$4 ,nev]!less1 ! bact]ia d multiply 9 ! *eese1 & z ! rip5+ goes on !y become m & m abundant1 al?\gh ! numb] fluctuates1 ris+ & fall+ "u diff]5t conditions4 ,:5 ! attempt is made to det]m9e ! relation ( ! diff]5t k9ds ( rip5+ to diff]5t k9ds ( bact]ia1 x has ?us f> met ) extremely little success4 ,t diff]5t flav\rs are due to ! rip5+ produc$ by diff]5t k9ds ( bact]ia w\ld appe> to be almo/ c]ta9 :5 we rememb]1 z we h already notic$1 ! diff]5t k9ds ( decomposition produc$ by diff]5t species ( bact]ia4 ,x w\ld seem1 moreov]1 t x ought n to be v difficult to sep>ate f ! rip5$ *eese ! bact]ia :i* are pres5t1 & ?us obta9 ! k9d ( bact]ia necess>y to produce ! desir$ rip5+4 ,b = "s reason ?is does n prove to be s easy 9 practice z x seems to be 9 !ory4 ,_m diff]5t species ( bact]ia h be5 sep>at$ f *eeses4 ,"o bact]iologi/1 /udy+ sev]al *eeses1 sep>at$ ab\t eighty diff]5t species !refrom1 & o!rs h f\nd p]haps z _m m f diff]5t s\rces4 ,moreov]1 exp]im5ts h be5 made ) a consid]able numb] ( ^! diff]5t k9ds ( bact]ia to det]m9e :e!r !y are capable ( produc+ normal rip5+4 ,^! exp]im5ts consi/ ( mak+ *eese out ( milk t has be5 depriv$ ( its bact]ia1 & :i* has be5 inoculat$ ) l>ge quantities ( ! species 9 "q4 ,hi!rto ^! exp]im5ts h n be5 v satisfactory4 ,9 "s cases ! *eese appe>s to rip5 sc>cely at all2 9 o!r cases ! rip5+ occurs1 b ! result+ *eese is ( a peculi> "*1 entirely unlike ! *eese t x is desir$ to imitate4 ,!re h be5 "o or two exp]im5ts 9 rec5t times t give a little m promise ( success ?an ! e>li] ones1 = a few species ( bact]ia h be5 us$ 9 rip5+ ) :at ! au?ors h ?\ght to be promis+ success4 ,! *eese made f ! milk artificially inoculat$ ) ^! species rip5s 9 a satisfactory mann] & gives "s ( ! "* desir$1 ?\gh up to ! pres5t "t 9 no case has ! typical normal rip5+ be5 produc$ 9 any ( ^! exp]im5ts4 ,b ^! exp]im5ts h demon/rat$ beyond "q t ! abnormal rip5+ :i* is common 9 *eese factories is due to ! pres5ce ( undesirable species ( bact]ia 9 ! milk4 ,_m ( ! exp]im5ts 9 mak+ *eeses by means ( artificial cultures ( bact]ia h result$ 9 decid$ly abnormal *eeses4 ,_m ( ! *eeses ?us manufactur$ h %[n imp]fections 9 rip5+ :i* are id5tical ) ^? actually occurr+ 9 ! *eese factory4 ,sev]al diff]5t species ( bact]ia h be5 f\nd :i*1 :5 artificially us$ ?us = rip5+ *eese1 w give rise to ! porosity & ! abnormal swell+ ( ! *eese already ref]r$ to 7,fig4 #bd74 ,o!rs produc$ bad ta/es & flav\rs1 & en\gh has be5 done 9 ?is l9e to demon/rate beyond p]adv5ture t ! abnormal rip5+ ( *eese is due prim>ily to ! gr[? ( improp] species !re94 ,q a long li/ ( species ( bact]ia :i* produce abnormal rip5+ h be5 isolat$ f *eeses1 & h be5 /udi$ & exp]im5t$ ) by bact]iologi/s4 ,z a result ( ?is /udy ( abnormal rip5+1 !re has be5 sugge/$ a me?od ( p>tially controll+ ^!--rem$y+ !m4 ,! me?od consi/s simply 9 te/+ ! f]m5t+ qualities ( ! milk us$4 ,a small sample ( milk f diff]5t dairies is all[$ to /& 9 ! *eese factory by itself until x und]goes its normal s\r+4 ,if ! f]m5tation or s\r+ t ?us occurs is ( a normal "*1 ! milk is reg>d$ z prop] = *eese mak+4 ,b if ! f]m5tation t occurs 9 any p>ticul> sample ( milk is unusual2 if an extraord9>y am\nt ( gas bubbles are produc$1 or if unpleasant smells & ta/es arise1 ! sample is reg>d$ z unfav\rable = *eese mak+1 & z likely to produce abnormal rip5+ 9 ! *eeses4 ,milk f ?is s\rce w\ld !re=e be exclud$ f ! milk t is to be us$ 9 *eese mak+4 ,?is1 ( c\rse1 is a t5tative & an unsatisfactory me?od ( controll+ ! rip5+1 & yet x is "o ( "s practical value to *eese mak]s4 ,x is ! only me?od t has yet be5 sugge/$ ( controll+ ! rip5+4 ,our bact]iologi/s1 ( c\rse1 are q confid5t t 9 ! future m practical results w be obta9$ along ?is l9e ?an 9 ! pa/4 ,if x is true t *eeses are rip5$ by bact]ia2 if x is true t diff]5t qualities 9 ! *eese are due to ! gr[? ( diff]5t species ( bact]ia dur+ ! rip5+1 x w\ld seem to be possible to obta9 ! prop] k9d ( bact]ia & to furni% !m to ! *eese mak] = artificially inoculat+ 8 *eese1 j z x has be5 possible to furni% artificially cultivat$ yea/s to ! brew]1 & z x has become possible to furni% artificially cultivat$ bact]ia to ! butt] mak]4 ,we mu/1 h[ev]1 recognise ?is to be a matt] = ! future4 ,up to ! pres5t "t no practical results along ! l9es ( bact]ia h be5 obta9$ :i* our *eese manufactur]s c make use ( 9 ! way ( controll+ ) any accuracy ?is process ( *eese rip5+4 ,?us x w be se5 t 9 ?is la/ dairy product bact]ia play ev5 a m important "p ?an 9 any ( ! o!rs4 ,! food value ( *eese is dep5d5t ^u ! case9 :i* is pres5t4 ,! m>ket price1 h[ev]1 is controll$ entirely by ! flav\r1 & ?is flav\r is a product ( bact]ial gr[?4 ,^u ! action ( bact]ia1 !n1 ! *eese mak] is absolutely dep5d5t2 & :5 our bact]iologi/s are able 9 ! future to inve/igate ?is matt] fur!r1 x seems to be at lea/ possible t !y may obta9 "s means ( enabl+ ! *eese mak] to control ! rip5+ accurately4 ,n only s1 b recognis+ ! great v>iety 9 ! flav\rs ( *eese1 & recognis+ t diff]5t k9ds ( bact]ia und\bt$ly produce diff]5t k9ds ( decomposition products1 x seems to be at lea/ possible t a "t w come :5 ! *eese mak] w be able to produce at-- w any p>ticul>ly desir$ flav\r 9 8 *eese by ! addition to x ( p>ticul> species ( bact]ia1 or p>ticul> mixtures ( species ( bact]ia :i* h be5 discov]$ to produce ! desir$ effects4 ,,*apt] ,,iv4 ,,bact]ia ,,9 ,,natural ,,processes4--,,agriculture4 ,?us f>1 9 consid]+ ! relations ( bact]ia to mank9d1 we h tak5 into acc\nt only ! arts & manufactures1 & h f\nd bact]ia play+ no unimportant "p 9 _m ( ! indu/ries ( our mod]n civiliz$ life4 ,s important are !y t !re is no "o :o is n directly affect$ by !m4 ,!re is h>dly a mom5t 9 our life :5 we are n us+ "s ( ! direct or indirect products ( bact]ial action4 ,we turn n[1 h[ev]1 to ! consid]ation ( a matt] ( ev5 m fundam5tal importance2 = :5 we come to /udy bact]ia 9 ,nature1 we f9d t !re are c]ta9 natural processes connect$ ) ! life ( animals & plants t are fundam5tally bas$ ^u _! p[]s4 ,liv+ ,nature appe>s limitless1 = life processes h be5 go+ on 9 ! _w ?r\gh c\ntless c5turies ) seem+ly unimpair$ vig\r4 ,at ! v bottom we f9d ?is nev]-end+ exhibition ( vital p[] dep5d5t ^u c]ta9 activities ( micro-organisms4 ,s ?or\ghly is ?is true t1 z we %all f9d aft] a %ort consid]ation1 ! cont9uance ( life ^u ! surface ( ! _w w\ld be impossible if bact]ial action 7 *eck$ = any consid]able l5g? ( "t4 ,! life ( ! globe is1 9 %ort1 dep5d5t ^u ^! micro-organisms4 ,,bact]ia ,,z ,,scav5g]s4 ,9 ! fir/ place1 we may notice ! value ( ^! organisms simply z scav5g]s1 keep+ ! surface ( ! e>? 9 ! prop] condition = ! gr[? ( animals & plants4 ,a l>ge tree 9 ! =e/ dies & falls to ! gr\nd4 ,= a :ile ! tree trunk lies !re a massive /ructure1 b 9 ! c\rse ( mon?s a sl[ *ange takes place 9 x4 ,! b>k becomes s(t5$ & falls f ! wood4 ,! wood also becomes m or less s(t5$2 x is prey$ ^u !n by insect life2 its d5sity decreases m & m1 until f9ally x crumbles into a s(t1 br[ni%1 p[d]y mass1 & ev5tually ! :ole s9ks into ! soil1 is ov]gr[n by mosses & o!r vegetation1 & ! tree trunk has disappe>$ f view4 ,9 ! same way ! body ( ! dead animal und]goes ! process ( ! s(t5+ ( its tissues by decay4 ,! s(t] p>ts ( ! body rapidly dissipate1 & ev5 ! bones !mselves ev5tually are cov]$ ) ! soil & dis9tegrat$1 until 9 "t !y1 too1 disappe> f any visible exi/5ce4 ,?is :ole process is "o ( decay1 & ! result is t ! solid mass ( ! body ( ! tree or ( ! animal has be5 decompos$4 ,:at has become ( x8 ,! answ] holds ! secret ( ,nature's et]nal fre%ness4 ,"p ( x has dissipat$ into ! air 9 ! =m ( gases & wat] vap\r2 "p ( x has *ang$ its composition & has become incorporat$ into ! soil1 ! f9al result be+ t ! body ( ! plant or animal disappe>s z su*1 & its sub/ance is conv]t$ into gase\s =m1 :i* is dissipat$ 9 ! air or into simple comp\nds :i* s9k into ! e>?4 ,?is :ole process ( decay ( organic life is "o 9 :i* bact]ia play ! mo/ important "p4 ,9 ! case ( ! decomposition ( ! woody matt] ( ! tree trunk1 ! process is begun by ! ag5cy ( m\lds1 = ?is gr\p ( organisms alone appe>s to be capable ( attack+ su* h>d woody /ructure4 ,! lat] "p ( ! decay1 h[ev]1 is l>gely c>ri$ on by bact]ial life4 ,9 ! decomposition ( ! animal tissues1 bact]ia alone are ! ag5ts4 ,?us ! process by :i* organic matt] is dissipat$ into ! air or incorporat$ into ! soil is "o :i* is prim>ily presid$ ov] by bact]ial life4 ,view+ ?is matt] 9 a purely me*anical light1 ! importance ( bact]ia 9 ?us act+ z scav5g]s c h>dly be ov]e/imat$4 ,if we ?9k = a mom5t ( ! condition ( ! _w 7 !re no su* decompos+ ag5ts to rid ! e>?'s surface ( ! dead bodies ( animals & plants1 we %all see t long s9ce ! e>? w\ld h be5 un9habitable4 ,if ! dead bodies ( plants & animals ( pa/ ages simply accumulat$ on ! surface ( ! gr\nd )\t any =ces to r$uce !m into simple comp\nds = dissipation1 by _! v bulk !y w\ld h long s9ce completely cov]$ ! surface ( ! e>? s z to af=d no possible room = fur!r gr[? ( plants & animals4 ,9 a purely me*anical way1 !n1 bact]ia z decomposition ag5ts are necess>y to keep ! surface ( ! e>? fre% & un5cumb]$ s t life c cont9ue4 ,,bact]ia ,,z ,,ag5ts ,,9 ,,nature',s ,,food ,,cycle4 ,b ! matt] by no means ends "h4 ,:5 we come to ?9k ( x1 x is a matt] ( consid]able surprise t ! surface ( ! e>? has be5 able to cont9ue produc+ animals & plants = ! _m millions ( ye>s dur+ :i* life has be5 9 exi/5ce4 ,plants & animals bo? require food1 animals dep5d+ :olly ^u plants !re=4 ,plants1 h[ev]1 equally ) animals1 require food1 & al?\gh !y obta9 a consid]able portion ( _! food f ! air1 yet no inconsid]able "p ( x is obta9$ f ! soil4 ,! "q is =c$ ^u u1 !re=e1 z to :y ! soil has n long s9ce become exhau/$ ( food4 ,h[ c\ld ! soil cont9ue to support plants ye> aft] ye> = millions ( ye>s1 & yet rema9 z f]tile z ev]8 ,! explanation ( ?is ph5om5on is 9 ! simple fact t ! processes ( ,nature are su* t ! same food is us$ ov] & ov] aga91 fir/ by ! plant1 !n by ! animal1 & !n aga9 by ! plant1 & !re is no necessity = any end ( ! process s long z ! sun furni%es en]gy to keep ! circulation cont9u\s4 ,"o phase ( ?is transf]5ce ( food f animal to plant & f plant to animal is famili> to ne>ly e "o4 ,x is a well-kn[n fact t animals 9 _! respiration consume oxyg51 b exhale x aga9 9 comb9ation ) c>bon z c>bonic dioxide4 ,on ! o!r h&1 plants 9 _! life consume ! c>bonic dioxide & exhale ! oxyg5 aga9 z free oxyg54 ,?us ea* ( ^! k+doms makes use ( ! excret$ product ( ! o!r1 & ?is process c g on indef9itely1 ! animals furni%+ our atmosph]e ) pl5ty ( c>bonic acid = plant life1 & ! plants excret+ into ! atmosph]e at ! same "t an abundant suffici5cy ( oxyg5 = animal life4 ,! oxyg5 ?us passes 9 an endless r\nd f animal to plant & f plant to animal4 ,a simil> cycle is true ( all ! o!r foods ( animal & plant life1 ?\gh 9 reg>d to ! o!rs ! op]ation is m complex & m memb]s are requir$ to complete ! *a94 ,! transf]5ce ( matt] ?r\gh a s]ies ( *anges by :i* x is br\ght f a condition 9 :i* x is prop] food = plants back aga9 into a condition :5 x is once m a prop] food = plants1 is "o ( ! int]e/+ discov]ies ( mod]n sci5ce1 & "o 9 :i*1 z we %all see1 bact]ia play a mo/ important "p4 ,?is food cycle is illu/rat$ r\ghly by ! accompany+ diagram2 b 9 ord] to und]/& x1 an explanation ( ! v>i\s /eps 9 ?is cycle is necess>y4 ,x w be notic$ t at ! bottom ( ! circle repres5t$ 9 ,fig4 #be1 at ,a1 are giv5 v>i\s +r$i5ts :i* are f\nd 9 ! soil & :i* =m plant foods4 ,plant foods1 z may be se5 !re1 are obta9$ p>tly f ! air z c>bonic dioxide & wat]2 b ano!r portion comes f ! soil4 ,among ! soil +r$i5ts ! mo/ prom95t are nitrates1 :i* are ! =ms ( nitrog5 comp\nds mo/ easily made use ( by plants z a s\rce ( ?is important elem5t4 ,x %\ld be /at$ also t !re are o!r comp\nds 9 ! soil :i* furni% plants ) "p ( _! food--comp\nds conta9+ potassium1 phosphorus1 & "s o!r elem5ts4 ,= simplicity's sake1 h[ev]1 ^! w be left out ( consid]ation4 ,beg9n+ at ! bottom ( ! cycle 7,fig4 #be ,a71 plant life seizes ! gases f ! air & ^! foods f ! soil1 & by means ( ! en]gy furni%$ x by ! sun's rays builds ^! simple *emical comp\nds into m complex ones4 ,?is gives u ! second /ep1 z %[n 9 ,fig4 #be ,b1 ! products ( plant life4 ,^! products ( plant life consi/ ( su* mat]ials z sug>1 />*es1 fats1 & proteids1 all ( :i* h be5 manufactur$ by ! plant f ! +r$i5ts furni%$ x f ! soil & air1 & ?r\gh ! ag5cy ( ! sun's rays4 ,^! products ( plant life n[ =m foods = ! animal k+dom4 ,/>*es1 fats1 & proteids are animal foods1 & ^u su* complex bodies alone c ! animal k+dom be f$4 ,animal life1 /&+ high up 9 ! circle1 is n capable ( extract+ its nutrim5t f ! soil1 b mu/ take ! m complex foods :i* h be5 manufactur$ by plant life4 ,^! complex foods ent] n[ into ! animal & take _! place 9 ! animal body4 ,by ! animal activities1 "s ( ! foods are at once decompos$ into c>bonic acid & wat]1 :i*1 be+ dissipat$ into ! air1 are br\ght back at once into ! condition 9 :i* !y c s]ve aga9 z plant food4 ,?is "p ( ! food is ?us br\ght back aga9 to ! bottom ( ! circle 7,fig4 #be1 dott$ l9es74 ,b :ile x is true t animals d ?us r$uce "s ( _! foods to ! simple condition ( c>bonic acid & wat]1 ?is is n true ( mo/ ( ! foods :i* conta9 nitrog54 ,! nitrog5\s foods are z necess>y = ! life z ! c>bon foods1 & animals d n r$uce _! nitrog5\s foods to ! condition 9 :i* plants c prey ^u !m4 ,:ile plants furni% !m ) nitrog5\s food1 !y c n give x back to ! plants4 ,"p ( ! nitrog5\s foods animals build into new album9s 7,fig4 #be ,c72 b a "p ( !m !y r$uce at once into a some:at simpl] condition kn[n z urea4 ,urea is ! =m 9 :i* ! nitrog5 is commonly excret$ f ! animal body4 ,b urea is n a plant food2 = ord9>y plants are entirely unable to make use ( x4 ,"p ( ! nitrog5 eat5 by ! animal is /or$ up 9 its body1 & ?us ! body ( ! animal1 aft] x has di$1 conta9s ^! nitrog5 comp\nds ( high complexity4 ,b plants are n able to use ^! comp\nds4 ,a plant c n be f$ ^u muscle tissue1 nor ^u fats1 nor bones1 = ^! are comp\nds s complex t ! simple plant is unable to use !m at all4 ,s f>1 !n1 9 ! food cycle ! comp\nds tak5 f ! soil h be5 built up into comp\nds ( great] & great] complexity2 !y h rea*$ ! top ( ?is circle1 & no "p ( !m1 except "p ( ! c>bon & oxyg51 has become r$uc$ aga9 to plant food4 ,9 ord] t ?is mat]ial %\ld aga9 become capable ( ent]+ into ! life ( plants s z to g ov] ! circle aga91 x is necess>y = x to be once m r$uc$ f its highly complex condition into a simpl] "o4 ,n[ come into play ^! decomposition ag5cies :i* we h be5 /udy+ "u ! head ( scav5g]s4 ,x w be notic$ t ! next /ep 9 ! food cycle is tak5 by ! decomposition bact]ia4 ,^! organisms1 exi/+1 z we h already se51 9 ! air1 9 ! soil1 9 ! wat]1 & always ready to seize hold ( any organic sub/ance t may furni% !m ) food1 fe$ ^u ! products ( animal life1 :e!r !y are su* products z muscle tissue1 or fat1 or sug>1 or :e!r !y are ! excret$ products ( animal life1 su* z urea1 & produce !re9 ! *emical decomposition *anges already notic$4 ,z a result ( ?is *emical decomposition1 ! complex bodies are brok5 into simpl] & simpl] comp\nds1 & ! f9al result is a v ?or\gh de/ruction ( ! animal body or ! mat]ial excret$ by animal life1 & its r$uction into =ms simple en\gh = plants to use aga9 z foods4 ,?us ! bact]ia come 9 z a necess>y l9k to connect ! animal body1 or ! excretion f ! animal body1 ) ! soil aga91 & !re=e ) t "p ( ! circle 9 :i* ! mat]ial c once m s]ve z plant food4 ,b 9 ! decomposition t ?us occurs ?r\gh ! ag5cy ( ! putrefactive bact]ia x v commonly happ5s t "s ( ! food mat]ial is brok5 d[n into comp\nds too simple = use z plant food4 ,z w be se5 by a glance at ! diagram 7,fig4 #be ,d71 a portion ( ! cleavage products result+ f ! de/ruction ( ^! animal foods takes ! =m ( c>bonic-acid gas & wat]4 ,^! +r$i5ts are at once 9 condition = plant life1 z %[n by ! dott$ l9es4 ,!y pass (f into ! air1 & ! gre5 leaves ( vegetation ev]y:]e aga9 seize !m1 assimilate !m1 & use !m z food4 ,?us x is t ! c>bon & ! oxyg5 h complet$ ! cycle1 & h come back aga9 to ! position 9 ! circle :]e !y />t$4 ,9 reg>d to ! nitrog5 portion ( ! food1 h[ev]1 x v commonly happ5s t ! products :i* arise z ! result ( ! decomposition processes are n yet 9 prop] condition = plant food4 ,!y are r$uc$ into a condition actually too simple = ! use ( plants4 ,z a result ( ^! putrefactive *anges1 ! nitrog5 products ( animal life are brok5 frequ5tly into comp\nds z simple z ammonia 7,,nh#c71 or into comp\nds :i* ! *emi/s speak ( z nitrites 7,fig4 #be at ,d74 ,n[ ^! comp\nds are n ord9>ily )9 ! rea* ( plant life4 ,! luxuriant vegetation ( ! globe extracts its nitrog5 f ! soil 9 a =m m complex ?an ei!r ( ! comp\nds "h m5tion$2 =1 z we h se51 x is nitrates *iefly t furni% plants ) _! nitrog5 food factor4 ,b nitrates conta9 consid]able oxyg54 ,ammonia1 :i* is "o ( ! products ( putrefactive de- composition1 conta9s no oxyg51 & nitrites1 ano!r factor1 conta9s less oxyg5 ?an nitrates4 ,^! bodies are ?us too simple = plants to make use ( z a s\rce ( nitrog54 ,! *emical de/ruction ( ! food mat]ial :i* results f ! action ( ! putrefactive bact]ia is too ?or\gh1 & ! nitrog5 foods are n yet 9 condition to be us$ by plants4 ,n[ comes 9 ! ag5cy ( /ill ano!r class ( micro-organisms1 ! exi/5ce ( :i* has be5 demon/rat$ to u dur+ ! la/ few ye>s4 ,9 ! soil ev]y:]e1 especially 9 f]tile soil1 is a class ( bact]ia :i* has receiv$ ! "n ( nitrify+ bact]ia 7,fig4 #bf74 ,^! organisms gr[ 9 ! soil & fe$ ^u ! soil +r$i5ts4 ,9 ! c\rse ( _! life !y h some:at ! same action ^u ! simple nitrog5 cleavage products j m5tion$ z we h already notic$ ! v9eg>- produc+ species h ^u alcohol1 viz41 ! br++ ab\t a union ) oxyg54 ,!re are app>5tly sev]al diff]5t k9ds ( nitrify+ bact]ia ) diff]5t p[]s4 ,"s ( !m cause an oxidation ( ! nitrog5 products by means ( :i* ! ammonia is unit$ ) oxyg5 & built up into a s]ies ( products f9ally result+ 9 nitrates 7,fig4 #bf74 ,by ! action ( o!r species /ill high] nitrog5 comp\nds1 includ+ ! nitrites1 are fur!r oxidiz$ & built up into ! =m ( nitrates4 ,?us ^! nitrify+ organisms =m ! la/ l9k 9 ! *a9 t b9ds ! animal k+dom to ! vegetable k+dom 7,fig4 #be at #d74 ,= aft] ! nitrify+ organisms h oxidiz$ nitrog5 cleavage products1 ! results ( ! oxidation 9 ! =m ( nitrates or nitric acid are left 9 ! soil1 & may n[ be seiz$ ^u by ! roots ( plants1 & beg9 once m _! j\rney ar\nd ! food cycle4 ,9 ?is way x w be se5 t :ile plants1 by build+ up comp\nds1 =m ! connect+ l9k betwe5 ! soil & animal life1 bact]ia 9 ! o!r half ( ! cycle1 by r$uc+ !m aga91 give u ! connect+ l9k betwe5 animal life & ! soil4 ,! food cycle w\ld be z incomplete )\t ! ag5cy ( bact]ial life z x w\ld be )\t ! ag5cy ( plant life4 ,b ev5 yet ! food cycle is n complete4 ,"s ( ! processes ( decomposition appe> to cause a portion ( ! nitrog5 to fly out ( ! circle at a tang5t4 ,9 ! process ( decomposition :i* is go+ on ?r\gh ! ag5cy ( micro-organisms1 a consid]able "p ( ! nitrog5 is dissipat$ into ! air 9 ! =m ( free nitrog54 ,:5 a bit ( meat decays1 "p ( ! meat is1 inde$1 conv]t$ into ammonia or o!r nitrog5 comp\nds1 b if ! putrefaction is all[$ to g on1 9 ! end a consid]able portion ( x w be brok5 into /ill simpl] =ms1 & ! nitrog5 w f9ally be dissipat$ into ! air 9 ! =m ( free nitrog54 ,?is dissipation ( free nitrog5 into ! air is go+ on 9 ! _w :]ev] putrefaction takes place4 ,:]ev] decomposition ( nitrog5 products occurs "s free nitrog5 is elim9at$4 ,n[1 ?is "p ( ! nitrog5 has pass$ beyond ! rea* ( plants1 = plants c n extract free nitrog5 f ! air4 ,9 ! diagram ?is is repres5t$ z a portion ( ! mat]ial :i*1 ?r\gh ! ag5cy ( ! decomposition bact]ia1 has be5 ?r[n out ( ! cycle at a tang5t 7,fig4 #be ,e74 ,x w1 ( c\rse1 be pla9 f ?is t ! /ore ( nitrog5 food mu/ be con/antly dim9i%+4 ,! soil may h be5 orig9ally suppli$ ) a giv5 quantity ( nitrog5 comp\nd1 b if ! decomposition products are caus+ consid]able quantities ( ?is nitrog5 to be dissipat$ 9 ! air1 x pla9ly foll[s t ! total am\nt ( nitrog5 food ^u :i* ! animal & vegetable k+doms c dep5d is becom+ con/antly r$uc$ by su* dissipation4 ,!re are /ill o!r me?ods by :i* nitrog5 is be+ lo/ f ! food cycle4 ,fir/1 we may notice t ! ord9>y processes ( vegetation result 9 a gradual dra9+ ( ! soil & a ?r[+ ( its nitrog5 into ! ocean4 ,! body ( any animal or any plant t *ances to fall into a brook or riv] is ev5tually c>ri$ to ! sea1 & ! products ( its decomposition pass into ! ocean & are1 ( c\rse1 lo/ to ! soil4 ,n[1 :ile ?is gradual extraction ( nitrog5 f ! soil by dra9age is a sl[ "o1 x is nev]!less a sure "o4 ,x is f> m rapid 9 ^! ye>s ( civiliz$ life ?an 9 =m] times1 s9ce ! products ( ! soil are giv5 to ! city1 & !n are ?r[n into its sewage ,our cities1 !n1 ) our pres5t sy/em ( dispos+ ( sewage1 are dra9+ f ! soil ! nitrog5 comp\nds & ?r[+ !m away4 ,9 yet ano!r direction mu/ x be notic$ t our nitrog5 comp\nds are be+ lo/ to plant life--viz41 by ! use ( v>i\s nitrog5 comp\nds to =m explosives4 ,gunp[d]1 nitro-glyc]9e1 dynamite1 9 fact1 ne>ly all ! explosives t are us$ ! _w ov] = all sorts ( purposes1 are nitrog5 comp\nds4 ,:5 !y are explod$ ! nitrog5 ( ! comp\nd is dissipat$ into ! air 9 ! =m ( gas1 mu* ( x 9 ! =m ( free nitrog54 ,! basis f :i* explosive comp\nds are made conta9s nitrog5 9 ! =m 9 :i* x c be us$ by plants4 ,saltpetre1 = example1 is equally good z a f]tiliz] & z a basis = gunp[d]4 ,! products ( ! explosion are gases no long] capable ( use by plants1 & ?us e explosion ( nitrog5 comp\nds aids 9 ?is gradual dissipation ( nitrog5 products1 tak+ !m f ! /ore ( plant foods & ?r[+ !m away4 ,all ( ^! ag5cies contribute to r$uce ! am\nt ( mat]ial circulat+ 9 ! food cycle ( ,nature1 & ?us seem to t5d inevitably 9 ! end t[>d a t]m9ation ( ! processes ( life2 = z soon z ! soil becomes exhau/$ ( its nitrog5 comp\nds1 s soon w plant life cease f lack ( nutrition1 & ! disappe>ance ( animal life w foll[ rapidly4 ,x is ?is loss ( nitrog5 9 l>ge measure t is =c+ our agriculturi/s to pur*ase f]tiliz]s4 ,! la/ fifte5 ye>s h %[n u1 h[ev]1 t "h aga9 we may look ^u our fri5ds1 ! bact]ia1 z ag5ts = c\nt]act+ ?is dissipat+ t5d5cy 9 ! g5]al processes ( ,nature4 ,bact]ial life 9 at lea/ two diff]5t ways appe>s to h ! function ( reclaim+ f ! atmosph]e m or less ( ?is dissipat$ free nitrog54 ,9 ! fir/ place1 x has be5 f\nd 9 ! la/ few ye>s t soil entirely free f all common plants1 b conta9+ c]ta9 k9ds ( bact]ia1 if all[$ to /& 9 contact ) ! air1 w sl[ly b surely ga9 9 ! am\nt ( nitrog5 comp\nds t x conta9s4 ,^! nitrog5 comp\nds are pla9ly manufactur$ by ! bact]ia 9 ! soil2 = unless ! bact]ia are pres5t !y d n accumulate1 & !y d accumulate inevitably if ! bact]ia are pres5t 9 ! prop] quantity & ! prop] species4 ,x appe>s t1 z a rule1 ?is fixation ( nitrog5 is n p]=m$ by any "o species ( microorganisms1 b by two or ?ree ( !m act+ toge!r4 ,c]ta9 comb9ations ( bact]ia h be5 f\nd :i*1 :5 inoculat$ 9 ! soil1 w br+ ab\t ?is fixation ( nitrog51 b no "o ( ! species is capable ( produc+ ?is result alone4 ,we d n "k to :at ext5t ^! organisms are di/ribut$ 9 ! soil1 nor h[ widely ?is nitrog5 fixation ?r\gh bact]ial life is go+ on4 ,x is only )9 a %ort "t t x has be5 demon/rat$ to exi/1 b we mu/ look ^u bact]ia 9 ! soil z "o ( ! factors 9 reclaim+ f ! atmosph]e ! dissipat$ free nitrog54 ,! second me?od by :i* bact]ia aid 9 ! reclaim+ ( ?is lo/ nitrog5 is by a comb9$ action ( c]ta9 species ( bact]ia & "s ( ! high] plants4 ,ord9>y gre5 plants1 z already not$1 are unable to make use ( ! free nitrog5 ( ! atmosph]e ,x 0 f\nd1 h[ev]1 "s fifte5 ye>s ago t "s species ( plants1 *iefly ! great family ( legumes1 :i* conta9s ! pea plant1 ! bean1 ! clov]1 etc1 are able1 :5 gr[+ 9 soil t is poor 9 nitrog51 to obta9 nitrog5 f "s s\rce o!r ?an ! soil 9 :i* !y gr[4 ,a pea plant 9 soil t conta9s no nitrog5 products & wat]$ ) wat] t conta9s no nitrog51 w1 aft] spr\t+ & gr[+ = a l5g? ( "t1 be f\nd to h accumulat$ a consid]able quantity ( fix$ nitrog5 9 its tissues ,! only s\rce ( ?is nitrog5 has be5 evid5tly f ! air :i* ba!s ! leaves ( ! plant or p]meates ! soil & ba!s its roots ,?is fact 0 at fir/ disput$1 b subsequ5tly demon/rat$ to be true1 & 0 f\nd lat] to be associat$ ) ! comb9$ action ( ^! legumes & c]ta9 soil bact]ia4 ,:5 a legume ?us ga9s nitrog5 f ! air1 x develops ^u its roots little bun*es kn[n z root nodules or root tub]cles4 ,! nodules are sometimes ! size ( ! head ( a pm1 & sometimes mu* l>g] ?an ?is1 occasionally rea*+ ! size ( a l>ge pea1 or ev5 l>g]4 ,^u microscopic exam9ation !y are f\nd to be little ne/s ( bact]ia ,9 "s way ! soil organisms 7,fig #bg7 make _! way into ! roots ( ! spr\t+ plant1 & f9d+ !re cong5ial environm5t1 develop 9 consid]able quantities & produce root tub]cles 9 ! root4 ,n[1 by "s entirely unkn[n process1 ! legume & ! bact]ia gr[+ toge!r succe$ 9 extract+ ! nitrog5 f ! atmosph]e :i* p]meates ! soil1 & fix+ ?is nitrog5 9 ! tub]cles & ! roots 9 ! =m ( nitrog5 comp\nds4 ,! result is t1 aft] a prop] p]iod ( gr[?1 ! am\nt ( fix$ nitrog5 9 ! plant is f\nd to h v decid$ly increas$ 7,fig #be ,e74 ,?is1 ( c\rse1 furni%es a />t+ po9t = ! reclaim+ ( ! lo/ atmosph]ic nitrog54 ,! legume cont9ues to live its usual life1 p]haps increas+ ! /ore ( nitrog5 9 its roots & /ems & leaves dur+ ! :ole ( its normal gr[?4 ,subsequ5tly1 aft] hav+ f9i%$ its ord9>y life1 ! plant w die1 & !n ! roots & /ems & leaves1 fall+ ^u ! gr\nd & becom+ buri$1 w be seiz$ ^u by ! decomposition bact]ia already m5tion$4 ,! nitrog5 :i* has ?us become fix$ 9 _! tissues w und]go ! de/ructive *anges already describ$4 ,?is w result ev5tually 9 ! production ( nitrates4 ,?us "s ( ! lo/ nitrog5 is re/or$ aga9 to ! soil 9 ! =m ( nitrates1 & may n[ />t on its r\te once m ar\nd ! cycle ( food4 ,x w be se51 !n1 t ! food cycle is a complete "o4 ,beg9n+ ) ! m9]al +r$i5ts 9 ! soil1 ! food matt] may />t on its circulation f ! soil to ! plant1 f ! plant to ! animal1 f ! animal to ! bact]ium & f ! bact]ium ?r\gh a s]ies ( o!r bact]ia back aga9 to ! soil 9 ! condition 9 :i* x />t$4 ,if1 p]*ance1 9 ?is progress ar\nd ! circle "s ( ! nitrog5 is ?r[n (f at a tang5t1 ?is1 too1 is br\ght back aga9 to ! circle ?r\gh ! ag5cy ( bact]ial life4 ,& s ! food mat]ial ( animals & plants cont9ues 9 ?is nev]-ceas+ circulation4 ,x is ! sunlight t furni%es ! en]gy = ! motion4 ,x is ! sunlight t =ces ! food ar\nd ! circle & keeps up ! endless *ange2 & s long z1 ! sun cont9ues to %9e ^u ! e>? !re seems to be no reason :y ! process %\ld ev] cease4 ,x is ?is repeat$ circulation t has made ! cont9uation ( life possible = ! millions & millions ( ye>s ( ! e>?'s hi/ory4 ,x is ?is cont9u$ circulation t makes life possible /ill1 & x is only ?is fact t ! food is ?us capable ( ev] circulat+ f animal to plant & f plant to animal t makes x possible = ! liv+ _w to cont9ue its exi/5ce4 ,b1 ah we h se51 "o half ( ?is great circle ( food *ange is dep5d5t ^u bact]ial life4 ,)\t ! bact]ial life ! animal body & ! animal excretion c\ld nev] be br\ght back aga9 )9 ! rea* ( ! plant2 & ?us1 7 x n = ! action ( ^! micro- organisms ! food cycle w\ld be incomplete & life c\ld n cont9ue indef9itely ^u ! surface ( ! e>?4 ,at ! v f\ndation1 ! cont9uation ( ! pres5t condition ( ,nature & ! exi/5ce ( life dur+ ! pa/ hi/ory ( ! _w has be5 fundam5tally bas$ ^u ! ubiquit\s pres5ce ( bact]ia & ^u _! cont9ual action 9 connection ) bo? de/ructive & con/ructive processes4 ,,relation ,,( ,,bact]ia ,,to ,,agriculture4 ,we h already notic$ t bact]ia play an important "p 9 "s ( ! agricultural indu/ries1 p>ticul>ly 9 ! dairy4 ,f ! consid]ation ( ! matt]s j discuss$1 x is manife/ t ^! organisms mu/ h an ev5 m intimate relation to ! f>m]'s occupation4 ,at ! f\ndation1 f>m+ consi/s 9 ! cultivation ( plants & animals1 & we h already se5 h[ ess5tial are ! bact]ia 9 ! cont9uance ( animal & plant life4 ,b aside f ^! !oretical consid]ations1 a little /udy %[s t 9 a v practical mann] ! f>m] is ev] mak+ use ( bact]ia1 z a rule1 q unconsci\sly1 b none ! less positively4 ,,spr\t+ ,,( ,,se$s4 ,ev5 9 ! spr\t+ ( se$s aft] !y are s[n 9 ! soil bact]ial life has its influ5ce4 ,:5 se$s are plac$ m moi/ soil !y g]m9ate "u ! influ5ce ( heat4 ,! ri* album9\s mat]ial 9 ! se$s furni%es excell5t food1 & inasmu* z bact]ia ab\nd 9 ! soil1 x is inevitable t !y %\ld gr[ 9 & fe$ ^u ! se$4 ,if ! moi/ure is excessive & ! heat consid]able1 !y v frequ5tly gr[ s rapidly 9 ! se$ z to de/roy its life z a se$l+4 ,! se$ rots 9 ! gr\nd z a result4 ,?is does n commonly occur1 h[ev]1 9 ord9>y soil4 ,b ev5 "h bact]ia d gr[ 9 ! se$1 ?\gh n s abundantly z to produce any injury4 ,inde$1 x has be5 claim$ t _! pres5ce 9 ! se$ 9 small quantities is a necessity = ! prop] spr\t+ ( ! se$4 ,x has be5 claim$ t _! gr[? t5ds to s(t5 ! food mat]ial 9 ! se$1 s t ! "y se$l+ c m readily absorb x = its own food1 & t )\t su* a s(t5+ ! se$ rema9s too h>d = ! plant to use4 ,?is may well be d\bt$1 h[ev]1 = se$s c app>5tly spr\t well en\gh )\t ! aid ( bact]ia4 ,b1 nev]!less1 bact]ia d gr[ 9 ! se$ dur+ its g]m9ation1 & ?us d aid ! plant 9 ! s(t5+ ( ! food mat]ial4 ,we c n reg>d !m z ess5tial to se$ g]m9ation4 ,x may well be claim$ t !y ord9>ily play at lea/ an incid5tal "p 9 ?is fundam5tal life process1 al?\gh x is unc]ta9 :e!r ! gr[? ( se$l+s is to any consid]able ext5t aid$ !reby4 ,,! ,,silo4 ,9 ! managem5t ( a silo ! f>m] has und\bt$ly ano!r great bact]iological problem4 ,9 ! attempt to pres]ve 8 summ]-gr[n food = ! w9t] use ( 8 animals1 he is h9d]$ by ! activity ( common bact]ia4 ,if ! food is kept moi/1 x is sure to und]go decomposition & be ru9$ 9 a %ort "t z animal food4 ,! f>m] f9ds x necess>y1 !re=e1 to dry "s k9ds ( foods1 l hay4 ,:ile he c ?us pres]ve "s foods1 o!rs c n be s treat$4 ,mu* ( ! rank gr[? ( ! f>m1 l corn/alks1 is good food :ile x is fre%1 b is ( little value :5 dri$4 ,! f>m] has f exp]i5ce & obs]vation discov]$ a me?od ( manag+ bact]ial gr[? :i* enables him to avoid _! ord9>y evil effects4 ,?is is by ! use ( ! silo4 ,! silo is a l>ge1 heavily built box1 :i* is op5 only at ! top4 ,9 ! silo ! gre5 food is pack$ tightly1 & :5 full all access ( air is exclud$1 except at its surface4 ,"u ^! conditions ! food rema9s moi/1 b nev]!less does n und]go its ord9>y f]m5tations & putrefactions1 & may be pres]v$ = mon?s )\t be+ ru9$4 ,! food 9 su* a silo may be tak5 out mon?s aft] x is pack$1 & w /ill be f\nd to be 9 good condition = food4 ,x is true t x has *ang$ its "* some:at1 b x is n decay$1 & is eag]ly eat5 by cattle4 ,we are yet v ignorant ( ! nature ( ! *anges :i* occur m ! food :ile 9 ! silo4 ,! food is n pres]v$ f f]m5tation4 ,:5 ! siloxis pack$ sl[ly1 a v decid$ f]m5tation occurs by :i* ! mass is rais$ to a high temp]ature 7#adj degrees ,f4 to #afj degrees ,f474 ,?is heat+ is produc$ by c]ta9 species ( bact]ia :i* gr[ readily ev5 at ?is high temp]ature4 ,! f]m5tation uses up ! air 9 ! silo to a c]ta9 ext5t & produces a settl+ ( ! mat]ial :i* /ill fur!r excludes air4 ,! fir/ f]m5tation soon ceases1 & aft]w>d only sl[ *anges occur4 ,c]ta9 acid- produc+ bact]ia aft] a little beg9 to gr[ sl[ly1 & 9 "t ! silage is r5d]$ some:at s\r by ! production ( acetic acid4 ,b ! exclusion ( air1 ! close pack+1 & ! small am\nt ( moi/ure appe> to prev5t ! gr[? ( ! common putrefactive bact]ia1 & ! silage rema9s good = a long "t4 ,9 o!r me?ods ( fill+ ! silo1 ! food is v quickly pack$ & d5sely cr[d$ toge!r s z to exclude z mu* air z possible f ! beg9n+4 ,"u ^! conditions ! lack ( moi/ure & air prev5ts f]m5tative action v l>gely4 ,only c]ta9 acid-produc+ organisms gr[1 & ^! v sl[ly4 ,! ess5tial result 9 ei!r case is t ! common putrefactive bact]ia are prev5t$ f gr[+1 probably by lack ( suffici5t oxyg5 & moi/ure1 & ?us ! decay is prev5t$4 ,! closely pack$ food (f]s j ! same unfav\rable condition = ! gr[? ( common putrefactive bact]ia t we h already se5 (f]$ by ! h>d-press$ *eese1 & ! bact]ia gr[? is 9 ! same way held 9 *eck4 ,our k ( ! matt] is z yet v slight1 b we d "k en\gh to und]/& t ! successful managem5t ( a silo is dep5d5t ^u ! manipulation ( bact]ia4 ,,! ,,f]tility ,,( ,,! ,,soil4 ,! f>m]'s sole duty is to extract food f ! soil4 ,?is he does ei!r directly by rais+ crops1 or indirectly by rais+ animals :i* fe$ ^u ! products ( ! soil4 ,9 ei!r case ! f]tility ( ! soil is ! fundam5tal factor 9 8 success4 ,?is f]tility is a gift to him f ! bact]ia4 ,ev5 9 ! fir/ =mation ( soil he is 9 a measure dep5d5t ^u bact]ia4 ,soil1 z is well kn[n1 is produc$ 9 l>ge "p by ! crumbl+ ( ! rocks into p[d]4 ,?is crumbl+ we g5]ally call wea!r+1 & reg>d x z due to ! effect ( moi/ure & cold ^u ! rocks1 toge!r ) ! oxidiz+ action ( ! air4 ,d\btless ?is is true1 & ! wea!r+ action is l>gely a physical & *emical "o4 ,nev]!less1 9 ?is fundam5tal process ( rock dis9tegration bact]ial action plays a "p1 ?\gh p]haps a small "o4 ,"s species ( bact]ia1 z we h se51 c live ^u v simple foods1 f9d+ 9 free nitrog5 & c>bonates suffici5tly highly complex mat]ial = _! life4 ,^! organisms appe> to gr[ on ! b>e surface ( rocks1 assimilat+ nitrog5 f ! air1 & c>bon f "s widely diffus$ c>bonates or f ! ,,co#b 9 ! air4 ,_! secret$ products ( an acid nature help to s(t5 ! rocks1 & ?us aid 9 p]=m+ ! fir/ /ep 9 wea!r+4 ,! soil is n1 h[ev]1 all made up ( dis9tegrat$ rocks4 ,x conta9s1 besides1 v>i\s +r$i5ts :i* comb9e to make x f]tile4 ,among ^! are v>i\s sulphates :i* =m important p>ts ( plant foods4 ,^! sulphates appe> to be =m$1 9 "p1 at lea/1 by bact]ial ag5cy4 ,! decomposition ( proteids gives rise1 among o!r ?+s1 to hydrog5 sulphide 7,h#b,s74 ,?is gas1 :i* is ( common occurr5ce 9 ! atmosph]e1 is oxidiz$ by bact]ial gr[? into sulphuric acid1 & ?is is ! basis ( "p ( ! soil sulphates4 ,! deposition ( iron phosphates & iron silicates is probably also 9 a measure aid$ by bact]ial action4 ,all ( ^! processes are factors 9 ! =mation ( soil4 ,beyond mu* "q ! rock dis9tegration :i* occurs ev]y:]e 9 ,nature is *iefly ! result ( physical & *emical *anges1 b !re is reason = believ+ t ! physical & *emical processes are1 to a slight ext5t at lea/1 assi/$ by bact]ial life4 ,a m important factor ( soil f]tility is its nitrog5 cont5t1 )\t :i* x is completely b>r54 ,! orig9 ( ^! nitrog5 +r$i5ts has be5 m or less ( a puzzle4 ,f]tile soil ev]y:]e conta9s nitrates & o!r nitrog5 comp\nds1 & 9 c]ta9 p>ts ( ! _w !re are l>ge accumulations ( ^! comp\nds1 l ! nitrate b$s ( ,*ili4 ,t !y h come ultimately f ! free atmosph]ic nitrog5 seems c]ta91 & v>i\s attempts h be5 made to expla9 a me?od ( ?is nitrog5 fixation4 ,x has be5 sugge/$ t electrical dis*>ges 9 ! air may =m nitric acid1 :i* w\ld readily !n unite ) soil +r$i5ts to =m nitrates4 ,!re is little reason1 h[ev]1 = believ+ ?is to be a v important factor ,b 9 ! soil bact]ia we f9d und\bt$ly an effici5t ag5cy m ?is nitrog5 fixation4 ,z already se51 ! bact]ia are able to seize ! free atmosph]ic nitrog51 conv]t+ x into nitrite & nitrates4 ,we h also le>n$ t !y c act 9 connection ) legumes & "s o!r plants1 enabl+ !m to fix atmosph]ic nitrog5 & /ore x m _! roots4 ,by ^! two means ! nitrog5 +r$i5t 9 ! soil is prev5t$ f becom+ exhau/$ by ! processes ( dissipation con/antly go+ on4 ,fur!r1 by "s su* ag5cy mu/ we imag9e ! orig9al nitrog5 soil +r$i5t to h be5 d]iv$4 ,su* an organic ag5cy is ! only "o yet disc]n$ :i* appe>s to h be5 effici5t 9 furni%+ virg9 soil ) its nitrates1 & we mu/ !re=e look ^u bact]ia z ess5tial to ! orig9al f]tility ( ! soil4 ,b 9 ano!r direction /ill does ! f>m] dep5d directly ^u bact]ia ,! mo/ important factor 9 ! f]tility ( ! soil is ! "p ( x call$ humus4 ,?is humus is v complex1 & nev] alike 9 diff]5t soils ,x conta9s nitrog5 comp\nds 9 abundance1 toge!r ) sulphates1 phosphates1 sug>1 & _m o!r sub/ances4 ,x is ?is :i* makes ! g>d5 soil diff]5t f s&1 or ! ri* soil diff]5t f ! /]ile soil4 ,if ! soil is cultivat$ ye> aft] ye>1 its food +r$i5ts are sl[ly b surely exhau/$4 ,some?+ is tak5 f ! humus ea* ye>1 & unless ?is be replac$ ! soil ceases to be able to support life4 ,to keep up a con/ant yield f ! soil ! f>m] und]/&s t he mu/ apply f]tiliz]s m or less con/antly4 ,?is application ( f]tiliz]s is simply fe$+ ! crops4 ,"s ( ^! f]tiliz]s ! f>m] pur*ases1 & kn[s little or no?+ z to _! orig94 ,! mo/ common me?od ( fe$+ ! crops is1 h[ev]1 by ! use ( ord9>y b>ny>d manure4 ,! reason :y ?is mat]ial conta9s plant food we c und]/&1 s9ce x is made ( ! undige/$ "p ( food1 toge!r ) all ! urea & o!r excretions ( animals1 & conta9s1 !re=e1 besides v>i\s m9]als1 all ( ! nitrog5\s wa/e ( animal life4 ,^! secretions are n at fir/ fit = plant food4 ,! f>m] has le>n$ by exp]i5ce t su* excretions1 be=e !y are ( any use on 8 fields1 mu/ und]go a process ( sl[ *ange1 :i* is sometimes call$ rip5+4 ,fre% manure is sometimes us$ on ! fields1 b x is only made use ( by ! plants aft] ! rip5+ process has occurr$4 ,fre% animal excretions are ( little or no value z a f]tiliz]4 ,! f>m]1 !re=e1 commonly all[s x to rema9 9 heaps = "s "t1 & x und]goes a sl[ *ange1 :i* gradually conv]ts x into a condition 9 :i* x c be us$ by plants4 ,?is rip5+ is readily expla9$ by ! facts already consid]$ ,! fre% animal secretions consi/ ( v>i\s highly complex comp\nds ( nitrog51 & ! rip5+ is a process ( _! decomposition4 ,! proteids are brok5 to pieces1 & _! nitrog5 elem5ts r$uc$ to ! =m ( nitrates1 leuc91 etc1 or ev5 to ammonia or free nitrog54 ,fur!r1 a second process occurs1 ! process ( oxidation ( ^! nitrog5 comp\nds already notic$1 & ! ammonia & nitrites result+ f ! decomposition are built into nitrates4 ,9 %ort1 9 ?is rip5+ manure ! processes notic$ 9 ! fir/ "p ( ?is *apt] are tak+ place1 by :i* ! complex nitrog5\s bodies are fir/ r$uc$ & !n oxidiz$ to =m plant food4 ,! rip5+ ( manure is bo? an analytical & a syn!tical process4 ,by ! analysis1 proteids & o!r bodies are brok5 into v simple comp\nds1 "s ( !m1 inde$1 be+ dissipat$ into ! air1 b o!r portions are reta9$ & !n oxidiz$1 & ^! latt] become ! real f]tiliz+ mat]ials4 ,?r\gh ! ag5cy ( bact]ia ! compo/ heap ?us becomes ! great s\rce ( plant food to ! f>m]4 ,into ?is compo/ heap he ?r[s g>bage1 /raw1 vegetable & animal sub/ances 9 g5]al1 or any organic refuse :i* may be at h&4 ,! v>i\s bact]ia seize x all1 & cause ! decomposition :i* conv]ts x into plant food aga94 ,! rott+ ( ! compo/ heap is ?us a gigantic cultivation ( bact]ia4 ,?is k ( ! rip5+ process is fur!r tea*+ ! f>m] h[ to prev5t wa/e4 ,9 ! ord9>y decomposition ( ! compo/ heap n an inconsid]able portion ( ! nitrog5 is lo/ 9 ! air by dissipation z ammonia or free nitrog54 ,ev5 8 nitrates may be ?us lo/ by bact]ial action4 ,?is portion is lo/ to ! f>m] completely1 & he c only hope to replace x ei!r by pur*as+ nitrates 9 ! =m ( comm]cial f]tiliz]s1 or by reclaim+ x f ! air by ! use ( ! bact]ial ag5cies already notic$4 ,) ! k n[ at 8 comm& he is le>n+ to prev5t ?is wa/e4 ,9 ! decomposition "o l>ge factor ( loss is ! ammonia1 :i*1 be+ a gas1 is readily dissipat$ into ! air4 ,kn[+ ?is common result ( bact]ial action1 ! sci5ti/ has told ! f>m] t1 by add+ c]ta9 common *emicals to 8 decompos+ manure heap1 *emicals :i* w readily unite ) ammonia1 he may reta9 mo/ ( ! nitrog5 9 ?is heap 9 ! =m ( ammonia salts1 :i*1 once =m$1 no long] %[ a t5d5cy to dissipate into ! air4 ,ord9>y gypsum1 or sup]phosphates1 or pla/] w readily unite ) ammonia1 & ^! add$ to ! manure heap l>gely c\nt]act ! t5d5cy ( ! nitrog5 to wa/e1 ?us enabl+ ! f>m] to put back into 8 soil mo/ ( ! nitrog5 :i* 0 extract$ f x by 8 crops & !n us$ by 8 /ock4 ,8 vegetable crops raise ! nitrates into proteids4 ,8 animals fe$ ^u ! proteids1 & p]=m 8 "w or furni% him ) milk4 ,!n 8 bact]ia /ock take ! excret$ or refuse nitrog51 & 9 8 manure heap turn x back aga9 into nitrates ready to beg9 ! circle once m4 ,?is might g on almo/ indef9itely 7 x n = two facts1 ! f>m] s5ds nitrog5\s mat]ial (f 8 f>m 9 ! milk or gra9s or o!r nitrog5\s products1 :i* he sells1 & ! decomposition processes1 z we h se51 dissipate "s ( ! nitrog5 into ! air z free nitrog54 ,to meet ?is em]g5cy & loss ! f>m] has ano!r me?od ( enri*+ ! soil1 aga9 dep5d+ ^u bact]ia4 ,?is is ! s- call$ gre5 manur+4 ,"h c]ta9 plants :i* seize nitrog5 f ! air are cultivat$ ^u ! field to be f]tiliz$1 &1 in/ead ( h>ve/+ a crop1 x is pl\gh$ into ! soil4 ,or p]haps ! tops may be h>ve/$1 ! re/ be+ pl\gh$ into ! soil4 ,! vegetable mat]ial ?us pl\gh$ 9 lies ov] a season & enri*es ! soil4 ,"h ! bact]ia ( ! soil come into play 9 sev]al directions4 ,fir/1 if ! crop s[$ be a legume1 ! soil bact]ia assi/ x to seize ! nitrog5 f ! air4 ,! only plants :i* are ( use 9 ?is gre5 manur+ are ^? :i* c1 ?r\gh ! ag5cy ( bact]ia1 obta9 nitrog5 f ! air & /ore x 9 _! roots4 ,second1 aft] ! crop is pl\gh$ into ! soil v>i\s decompos+ bact]ia seize ^u x1 pull+ ! comp\nds to pieces4 ,! c>bon is l>gely dissipat$ into ! air z c>bonic dioxide1 :]e ! next g5]ation ( plants c get hold ( x4 ,! m9]als & ! nitrog5 rema9 9 ! soil4 ,! nitrog5\s portions g ?r\gh ! same s]ies ( decomposition & syn!tical *anges already describ$1 & ?us ev5tually ! nitrog5 seiz$ f ! air by ! comb9$ action ( ! legumes & ! bact]ia is conv]t$ into nitrates1 & w s]ve = food = ! next set ( plants gr[n on ! same soil4 ,"h is ?us a practical me?od ( us+ ! nitrog5 assimilation p[]s ( bact]ia1 & reclaim+ nitrog5 f ! air to replace t :i* has be5 lo/4 ,?us x is t ! f>m]'s nitrog5 problem ( ! f]tile soil appe>s to resolve itself into a prop] h&l+ ( bact]ia4 ,^! organisms h /ock$ 8 soil 9 ! fir/ place4 ,!y conv]t all ( 8 compo/ heap wa/es into simple bodies1 "s ( :i* are *ang$ into plant foods1 :ile o!rs are at ! same "t lo/4 ,la/ly1 !y may be made to reclaim ?is lo/ nitrog51 & ! fann]1 s soon z he has requisite k ( ^! facts1 w be able to keep )9 8 control ! supply ( ?is important elem5t4 ,! cont9u$ f]tility ( ! soil is ?us a gift f ! bact]ia4 ,,bact]ia ,,z ,,s\rces ,,( ,,tr\ble ,,to ,,! ,,f>m]4 ,:ile ! topics already consid]$ comprise ! mo/ important factors 9 agricultural bact]iology1 ! f>m]'s relations to bact]ia d n end "h4 ,^! organisms come incid5tally into 8 life 9 _m ways4 ,!y are n always 8 aids z !y are 9 mo/ ( ! in/ances ?us f> cit$4 ,!y produce disease 9 8 cattle1 z w be notic$ 9 ! next *apt]4 ,bact]ia are ag5ts ( decomposition1 & !y are j z likely to decompose mat]ial :i* ! f>m] wi%es to pres]ve z !y are to decompose mat]ial :i* ! f>m] desires to und]go ! process ( decay4 ,!y are z ready to attack 8 fruits & vegetables z to rip5 8 cream4 ,! sk9 ( fruits & vegetables is a mod]ately good protection ( ! int]ior f ! attack ( bact]ia2 b if ! sk9 be brok5 9 any place1 bact]ia get 9 & cause decay1 & to prev5t x ! f>m] uses a cold cell>4 ,! bact]ia prev5t ! f>m] f pres]v+ meats = any l5g? ( "t unless he *ecks _! gr[? 9 "s way4 ,!y get into ! eggs ( 8 f[ls & ru9 !m4 ,_! tr\blesome nature 9 ! dairy 9 prev5t+ ! keep+ ( milk has already be5 notic$4 ,if he plants 8 se$s 9 v moi/1 damp wea!r1 ! soil bact]ia cause too rapid a decomposition ( ! se$s & !y rot 9 ! gr\nd in/ead ( spr\t+4 ,!y produce disagreeable od\rs1 & are ! cause ( mo/ ( ! peculi> smells1 good & bad1 ar\nd ! b>n4 ,!y attack ! organic matt] :i* gets into 8 well or brook or pond1 decompos+ x1 fill+ ! wat] ) disagreeable & p]haps poison\s products :i* r5d] x unfit to dr9k4 ,!y n only aid 9 ! decay ( ! fall5 tree 9 8 =e/s2 b 9 ! same way attack ! timb] :i* he wi%es to pres]ve1 especially if x is kept 9 a moi/ condition4 ,?us !y contribute l>gely to ! gradual de/ruction ( wood5 /ructures4 ,x is !re=e ! pres5ce ( ^! organisms :i* =ces him to dry 8 hay1 to smoke 8 hams1 to corn 8 beef1 to keep 8 fruits & vegetables cool & prev5t sk9 bruises1 to ice 8 dairy1 to protect 8 timb] f ra91 to use /one in/ead ( wood5 f\ndations = build+s1 etc4 ,9 g5]al1 :5 ! f>m] desires to get rid ( any organic refuse1 he dep5ds ^u bact]ia1 = !y are 8 sole ag5ts 7aside f fire7 = ! f9al de/ruction ( organic matt]4 ,:5 he wi%es to conv]t wa/e organic refuse into f]tiliz+ mat]ial1 he uses ! bact]ia ( 8 compo/ heap4 ,on ! o!r h&1 :5ev] he desires to pres]ve organic mat]ial1 ! bact]ia are ! enemies aga9/ :i* he mu/ c>efully gu>d4 ,?us ! f>m]'s life f ye>'s end to ye>'s end is 9 mo/ intimate association ) bact]ia4 ,^u !m he dep5ds to insure ! cont9u$ f]tility ( 8 soil & ! con/ant cont9u$ production ( good crops4 ,^u !m he dep5ds to turn into plant food all ! organic refuse f 8 h\se or f 8 b>n4 ,^u !m he dep5ds to repl5i% 8 /ock ( nitrog54 ,x is ^! organisms :i* furni% 8 dairy ) its butt] flav\rs & ) ! ta/e ( its *eese4 ,b1 on ! o!r h&1 aga9/ !m he mu/ be con/antly al]t4 ,all 8 food products mu/ be protect$ f _! ravages4 ,a successful f>m]'s life1 !n1 l>gely resolves itself into a skilful managem5t ( bact]ial activity4 ,to aid !m 9 de/roy+ or decompos+ ev]y?+ :i* he does n desire to pres]ve1 & to prev5t _! de/roy+ ! organic mat]ial :i* he wi%es to keep = future use1 is ! object ( a consid]able portion ( f>m lab\r2 & ! mo/ successful f>m] to-day1 & we believe ! mo/ successful f>m] ( ! future1 is ! "o :o mo/ intellig5tly & skilfully manipulates ^! gigantic =ces furni%$ him by ! gr[? ( 8 microscopical allies4 ,,relation ,,( ,,bact]ia ,,to ,,coal4 ,ano!r "o ( ,nature's processes 9 :i* bact]ia h play$ an important "p is 9 ! =mation ( coal4 ,x is unnecess>y to emphasize ! importance ( coal 9 mod]n civilization4 ,aside f its use z fuel1 ^u :i* civilization is dep5d5t1 coal is a s\rce ( an endless v>iety ( valuable products4 ,x is ! s\rce ( our illum9at+ gas1 & ammonia is "o ( ! products ( ! gas manufacture4 ,f ! coal also comes coal t>1 ! mat]ial f :i* su* a long s]ies ( valuable mat]ials1 z anil9e col\rs1 c>bolic acid1 etc1 is d]iv$4 ,! li/ ( products :i* we owe to coal is v long1 & ! value ( ?is mat]ial is h>dly to be ov]rat$4 ,9 ! prep>ation ( ^! +r$i5ts f coal bact]ia d n play any "p4 ,mo/ ( !m are d]iv$ by means ( di/illation4 ,b :5 ask$ = ! ag5ts :i* h giv5 u ! coal ( ! coal b$s1 we %all f9d t "h1 too1 we owe a great debt to bact]ia4 ,coal1 z is well kn[n1 has come f ! accumulation ( ! luxuriant vegetable gr[? ( ! pa/ geological ages4 ,x has !re=e be5 directly furni%$ u by ! vegetation ( ! gre5 plants ( ! pa/1 &1 9 g5]al1 x repres5ts s mu* c>bonic dioxide :i* ^! plants h extract$ f ! atmosph]e4 ,b :ile ! gre5 plants h be5 ! active ag5ts 9 produc+ ?is assimilation1 bact]ia h play$ an important "p 9 coal manufacture 9 two diff]5t directions4 ,! fir/ appe>s to be 9 furni%+ ^! plants ) nitrog54 ,)\t a /ore ( fix$ nitrog5 9 ! soil ^! c>bonif]\s plants c\ld n h gr[n4 ,?is matt] has already be5 consid]$4 ,we h no v absolute k z to ! ag5cy ( bact]ia 9 furni%+ nitrog5 = ?is vegetation 9 pa/ ages1 b !re is e reason to believe t 9 ! pa/1 z 9 ! pres5t1 ! *ief s\rce ( organic nitrog5 has be5 f ! atmosph]e & d]iv$ f ! atmosph]e ?r\gh ! ag5cy ( bact]ia4 ,9 ! abs5ce ( any o!r kn[n factor we may be pretty safe 9 ! assumption t bact]ia play$ an important "p 9 ?is nitrog5 fixation1 & t bact]ia mu/ !re=e be reg>d$ z ! ag5ts :i* h furni%$ u ! nitrog5 /or$ 9 ! coal4 ,b 9 a lat] /age ( coal =mation bact]ia h contribut$ m directly to ! =mation ( coal4 ,coal is n simply accumulat$ vegetation4 ,! coal ( our coal b$s is v diff]5t 9 its *emical composition f ! wood ( ! trees4 ,x conta9s a mu* high] p]c5tage ( c>bon & a l[] p]c5tage ( hydrog5 & oxyg5 ?an ord9>y vegetable sub/ances4 ,! conv]sion ( ! vegetation ( ! c>bonif]\s ages into coal 0 accompani$ by a gradual loss ( hydrog5 & a consequ5t increase 9 ! p]c5tage ( c>bon4 ,x is ?is *ange t has add$ to ! d5sity ( ! sub/ance & makes ! great] value ( coal z fuel4 ,!re is little d\bt n[ z to ! me?od by :i* ?is woody mat]ial ( ! pa/ has be5 conv]t$ into coal4 ,! same process appe>s to be go+ on 9 a simil> mann] to-day 9 ! peat b$s ( v>i\s nor!rn c\ntries4 ,! fall5 vegetation1 trees1 trunks1 bran*es1 & leaves1 accumulate 9 masses1 &1 :5 ! conditions ( moi/ure & temp]ature are "r1 beg9 to und]go a f]m5tation4 ,ord9>ily ?is action ( bact]ia1 z already notic$1 produces an almo/ complete ?\gh sl[ oxidation ( ! c>bon1 & results 9 ! total decay ( ! vegetable matt]4 ,b if ! vegetable mass be cov]$ by wat] & mud "u prop] conditions ( moi/ure & temp]ature1 a diff]5t k9d ( f]m5tation arises :i* does n produce su* complete decay4 ,! cov]+ ( wat] prev5ts ! access ( oxyg5 to ! f]m5t+ mass1 an oxidation ( ! c>bon is l>gely prev5t$1 & ! vegetable matt] sl[ly *anges its "*4 ,"u ! influ5ce ( ?is sl[ f]m5tation1 aid$1 probably by pressure1 ! mass becomes m & m solid & cond5s$1 its woody "* becomes less & less di/9ct1 & !re is a gradual loss ( ! hydrog5 & ! oxyg54 ,d\btless !re is a loss ( c>bon also1 = !re is an evolution ( m>% gas :i* conta9s c>bon4 ,b1 9 ?is sl[ f]m5tation tak+ place "u ! wat] 9 peat bogs & m>%es ! c>bon loss is relatively small2 ! woody mat]ial does n become completely oxidiz$1 z x does 9 free op]ations ( decay4 ,! loss ( hydrog5 & oxyg5 f ! mass is great] ?an t ( c>bon1 & ! p]c5tage ( c>bon !re=e increases4 ,?is is n ! ord9>y k9d ( f]m5tation t goes on 9 vegetable accumulations4 ,x requires special conditions & possibly special k9ds ( f]m5t+ organisms4 ,peat is n =m$ 9 all climates4 ,9 w>m regions1 or :]e ! woody matt] is freely expos$ to ! air1 ! f]m5tation ( vegetable matt] is m complete1 & x is entirely de/roy$ by oxidation4 ,x is only 9 cold] regions & :5 cov]$ ) wat] t ! de/ruction ( ! organic matt] /ops %ort ( decay4 ,b su* incomplete f]m5tation is /ill go+ on 9 _m p>ts ( ! _w1 & by its means vegetable accumulations are be+ conv]t$ into peat4 ,?is =mation ( peat appe>s to be a fir/ /ep 9 ! =mation ( d5s] coal4 ,by a cont9uation ( ! same processes ! mass becomes /ill m d5se & solid4 ,z we pass f ! top to ! bottom ( su* an accumulation ( peat1 we f9d x becom+ d5s] & d5s]1 & at ! bottom x is commonly ( a h>d consi/5ce1 br[ni% 9 col\r1 & ) only slight traces ( ! orig9al woody /ructure4 ,su* mat]ial is call$ lignite4 ,x conta9s a high] p]c5tage ( c>bon ?an peat1 b a l[] p]c5tage ?an coal1 & is pla9ly a /ep 9 coal =mation4 ,b ! process goes on1 ! hydrog5 & oxyg5 loss cont9u+ until !re is f9ally produc$ true coal4 ,if ?is is ! correct und]/&+ ( ! =mation ( coal1 we see t we h pla9ly a process 9 :i* bact]ial life has _h a l>ge & important %>e4 ,we are1 ( c\rse1 d5sely ignorant ( ! exact processes go+ on4 ,we "k no?+ positively z to ! k9d ( microorganisms :i* produce ?is sl[1 peculi> f]m5tation4 ,z yet1 ! f]m5tation go+ on 9 ! =mation ( ! peat has n be5 /udi$ by ! bact]iologi/s1 & we d n "k f direct exp]im5t t x is a matt] ( bact]ial action4 ,x has be5 commonly reg>d$ z simply a sl[ *emical *ange1 b its g5]al simil>ity to o!r f]m5tative processes is s great t we c h little hesitation 9 attribut+ x to micro-organisms1 & d\btless to "s =ms ( plants alli$ to bact]ia4 ,!re is no reason = d\bt+ t bact]ia exi/$ 9 ! geological ages ) ess5tially ! same p[]s z !y n[ possess1 & to "s =ms ( bact]ia :i* gr[ 9 ! abs5ce ( oxyg5 c we probably attribute ! sl[ *ange :i* has produc$ coal4 ,"h1 !n1 is ano!r great s\rce ( weal? 9 ,nature = :i* we are dep5d5t ^u bact]ia4 ,:ile1 ( c\rse1 wat] & pressure 7 v ess5tial factors 9 ! deposition ( coal1 x 0 a peculi> k9d ( f]m5tation occurr+ 9 ! vegetation t br\ght ab\t ! *emical *anges 9 x :i* result$ 9 its trans=mation into coal4 ,! vegetation ( ! c>bonif]\s age 0 dep5d5t ^u ! nitrog5 fix$ by ! bact]ia1 & to ^! organisms also d we owe ! fact t ?is vegetation 0 /or$ = u 9 ! rocks4 ,,*apt] ,v4 ,,p>asitic ,,bact]ia ,,& ,,_! ,,relation ,,to ,,disease4 ,p]haps ! mo/ univ]sally kn[n fact 9 reg>d to bact]ia is t !y are ! cause ( disease4 ,x is ?is fact t has made !m objects ( su* wide int]e/4 ,?is is ! side ( ! subject t fir/ attract$ att5tion1 has be5 mo/ /udi$1 & 9 reg>d to :i* !re has be5 ! greate/ accumulation ( evid5ce4 ,s p]si/5tly has ! relation ( bact]ia to disease be5 discuss$ & emphasiz$ t ! majority ( read]s are h>dly able to disassociate ! two4 ,to mo/ p ! v ^w bact]ia is almo/ equival5t to disease1 & ! ?\ght ( swall[+ microbes 9 dr9k+ wat] or milk is decid$ly repugnant & al>m+4 ,9 ! public m9d x is only necess>y to demon/rate t an article holds bact]ia to ?r[ x "u condemnation4 ,we h already se5 t bact]ia are to be reg>d$ z ag5ts = good1 & t f _! fundam5tal relation to plant life !y mu/ be look$ ^u z our fri5ds r ?an z our enemies4 ,x is true t !re is ano!r side to ! /ory :i* relates to ! p>asitic species4 ,^! p>asitic =ms may d u direct or indirect injury4 ,b ! species ( bact]ia :i* are capable ( do+ u any injury1 ! pa?og5ic bact]ia1 are really v few comp>$ to ! great ho/ ( species :i* are h>mless4 ,a small numb] ( species1 p]haps a score or two1 are pa?og5ic1 :ile a mu* l>g] numb]1 am\nt+ to hundr$s & p]haps ?\s&s ( species1 are p]fectly h>mless4 ,?is latt] class d no injury ev5 ?\gh swall[$ by man 9 ?\s&s4 ,!y are n p>asitic1 & are unable to gr[ 9 ! body ( man4 ,_! pres5ce is entirely consi/5t ) ! mo/ p]fect heal?1 &1 inde$1 !re are "s reasons = believ+ t !y are sometimes directly b5eficial to heal?4 ,x is entirely unju/ to condemn all bact]ia because a few *ance to produce mis*ief4 ,bact]ia 9 g5]al are ag5ts = good r ?an ill4 ,!re are1 h[ev]1 "s species :i* cause mank9d mu* tr\ble by int]f]+ 9 "o way or ano!r ) ! normal processes ( life4 ,^! pa?og5ic bact]ia1 or disease g]ms1 d n all act alike1 b br+ ab\t injury to man 9 a numb] ( diff]5t ways4 ,we may recognise two diff]5t classes among !m1 :i*1 h[ev]1 we %all see are connect$ by int]m$iate types4 ,^! two classes are1 fir/1 ! pa?og5ic bact]ia1 :i* are n /rictly p>asitic b live free 9 ,nature2 &1 second1 ^? :i* live z true p>asites 9 ! bodies ( man or o!r animals4 ,to und]/& ! real relation ( ^! two classes1 we mu/ fir/ notice ! me?od by :i* bact]ia 9 g5]al produce disease4 ,,me?od ,,by ,,:i* ,,bact]ia ,,produce ,,disease4 ,s9ce x 0 fir/ cle>ly recognis$ t c]ta9 species ( bact]ia h ! p[] ( produc+ disease1 ! "q z to h[ !y d s has ev] be5 a prom95t "o ,ev5 if !y d gr[ 9 ! body1 :y %\ld _! pres5ce give rise to ! symptoms *>act]iz+ disease8 ,v>i\s answ]s to ?is "q h be5 giv5 9 ! pa/ ,x has be5 sugge/$ t 9 _! gr[? !y consume ! food ( ! body & ?us exhau/ x1 t !y produce an oxidation ( ! body tissues1 or t !y produce a r$uction ( ^! tissues1 or t !y me*anically int]f]e ) ! circulation ,none ( ^! sugge/ions h prov$ ( mu* value ,ano!r view 0 e>ly advanc$1 & has /ood ! te/ ( "t4 ,?is claim is t ! bact]ia :ile gr[+ 9 ! body produce poisons1 & ^! poisons !n h a direct action on ! body ,we h already notic$ t bact]ia dur+ _! gr[? 9 any m$ium produce a l>ge numb] ( biproducts ( decomposition4 ,we notic$ also t among ^! biproducts !re are "s :i* h a poison\s nature2 s poison\s are !y t :5 inoculat$ into ! body ( an animal !y may produce poison+ & dea?4 ,we h only to suppose t ! pa?og5ic bact]ia1 :5 gr[+ z p>asites 9 man1 produce su* poisons1 & we h at once an explanation ( ! me?od by :i* !y give rise to disease4 ,?is explanation ( g]m disease is m ?an simple !ory4 ,x has be5 9 _m cases cle>ly demon/rat$4 ,x has be5 f\nd t ! bact]ia :i* cause diph!ria1 tetanus1 typhoid1 tub]culosis1 & _m o!r diseases1 produce1 ev5 :5 gr[+ 9 common culture m$ia1 poisons :i* are ( a v viol5t nature4 ,^! poisons :5 inoculat$ into ! bodies ( animals give rise to mu* ! same symptoms z ! bact]ia d !mselves :5 gr[+ z p>asites 9 ! animals4 ,! *ief diff]5ce 9 ! results f inoculat+ an animal ) ! poison & ) ! liv+ bact]ia is 9 ! rapidity ( ! action4 ,:5 ! poison is inject$ ! poison+ symptoms are almo/ imm$iately se51 b :5 ! liv+ bact]ia are inoculat$ ! effect is only se5 aft] sev]al days or long]1 n1 9 %ort1 until ! inoculat$ bact]ia h _h "t en\gh to gr[ 9 ! body & produce ! poison 9 quantity4 ,x has n by any means be5 %[n t all pa?og5ic g]ms produce _! effect 9 ?is way1 b x has be5 prov$ to be ! real me?od 9 q a numb] ( cases1 & is extremely probable 9 o!rs4 ,:ile "s bact]ia p]haps produce results by a diff]5t me?od1 we mu/ recognise ! production ( poisons z at all ev5ts ! common direct cause ( ! symptoms ( disease4 ,?is explanation w enable u m cle>ly to und]/& ! relation ( diff]5t bact]ia to disease4 ,,pa?og5ic ,,g]ms ,,:i* ,,are ,,n ,,/rictly ,,p>asitic ,recognis+ t bact]ia may produce poisons1 we readily see t x is n always necess>y t !y %\ld be p>asites 9 ord] to produce tr\ble4 ,9 _! ord9>y gr[? 9 ,nature su* bact]ia w produce no tr\ble ,! poisons w be produc$ 9 decay+ mat]ial b w seldom be tak5 into ! human body4 ,^! poisons1 produc$ 9 ! fir/ /ages ( putrefaction1 are oxidiz$ by fur!r /ages ( decomposition into h>mless products4 ,b %\ld x happ5 t "s ( ^! bact]ia obta9$ a *ance to gr[ vigor\sly = a :ile 9 organic products t are subsequ5tly swall[$ z man's food1 x is pla9 t evil results might foll[4 ,if su* food is swall[$ by man aft] ! bact]ia h produc$ _! poison\s bodies1 x w t5d to produce an imm$iate poison+ ( 8 sy/em4 ,! effect may be sudd5 & sev]e if consid]able quantity ( ! poison\s mat]ial is swall[$1 or slight b protract$ if small quantities are repeat$ly consum$ 9 food4 ,su* in/ances are n uncommon4 ,well-kn[n examples are cases ( ice-cream poison+1 poison+ f eat+ *eese or f dr9k+ milk1 or 9 n a few in/ances f eat+ fi% or meats )9 :i* bact]ia h _h opportunity = gr[?4 ,9 all ^! cases ! poison is swall[$ 9 quantity suffici5t to give rise quickly to sev]e symptoms1 sometimes result+ fatally1 & at o!r times pass+ (f z soon z ! body succe$s 9 ?r[+ (f ! poisons4 ,9 o!r cases /ill1 h[ev]1 ! am\nt ( poison swall[$ may be v slight1 too slight to produce mu* effect unless ! same be consum$ repeat$ly4 ,all su* tr\ble may be attribut$ to f]m5t$ or p>tly decay$ food4 ,x is difficult to di/+ui% su* in/ances f o!rs produc$ 9 a slightly diff]5t way1 z foll[s3 ,x may happ5 t ! bact]ia :i* gr[ 9 food products cont9ue to gr[ 9 ! food ev5 aft] x is swall[$ & has pass$ into ! /oma* or inte/9es4 ,?is appe>s p>ticul>ly true ( milk bact]ia4 ,"u ^! conditions ! bact]ia are n 9 any prop] s5se p>asitic1 s9ce !y are simply liv+ 9 & fe$+ ^u ! same food :i* !y consume outside ! body1 & are n fe$+ ^u ! tissues ( man4 ,! poisons :i* !y produce w cont9ue to be develop$ z long z ! bact]ia cont9ue to gr[1 :e!r 9 a milk pail or a human /oma*4 ,if n[ ! poisons are absorb$ by ! body1 !y may produce a mild or sev]e disease :i* w be m or less la/+1 cont9u+ p]haps z long z ! same food & ! same bact]ia are suppli$ to ! individual4 ,! mo/ important disease ( ?is class appe>s to be ! dread$ *ol]a infantum1 s common among infants :o fe$ ^u c['s milk 9 w>m wea!r4 ,x is easy to und]/& ! nature ( ?is disease :5 we rememb] ! great numb] ( bact]ia 9 milk1 especially 9 hot wea!r1 & :5 we rememb] t ! delicate organism ( ! infant w be ?r[n at once into disord] by slight am\nts ( poison :i* w\ld h no appreciable effect ^u ! /rong] adult4 ,we c easily und]/&1 fur!r1 h[ ! disease readily yields to treatm5t if c>e is tak5 to /]ilize ! milk giv5 to ! pati5t4 ,we d n "k to-day ! ext5t ( ! tr\bles :i* are produc$ by bact]ia ( ?is sort4 ,!y w1 ( c\rse1 be *iefly connect$ ) our food products1 & commonly1 ?\gh n always1 w affect ! dige/ive functions4 ,x is probable t _m ( ! cases ( summ] di>rhoea are produc$ by "s su* cause1 & if !y c\ld be trac$ to _! s\rce w\ld be f\nd to be produc$ by bact]ial poisons swall[$ ) food or dr9k1 or by simil> poisons produc$ by bact]ia gr[+ 9 su* food aft] x is swall[$ by ! individual4 ,9 hot wea!r1 :5 bact]ia are s abundant ev]y:]e & gr[+ s rapidly1 x is impossible to avoid su* dang]s completely )\t ex]cis+ ov] all food a gu>d :i* w\ld be decid$ly oppressive4 ,x is well to be> 9 m9d1 h[ev]1 t ! mo/ common & mo/ dang]\s s\rce ( su* poisons is milk or its products1 & = ?is reason "o %\ld hesitate to dr9k milk 9 hot wea!r unless x is ei!r q fre% or has be5 boil$ to de/roy its bact]ia4 ,,pa?og5ic ,,bact]ia ,,:i* ,,are ,,true ,,p>asites4 ,?is class ( pa?og5ic bact]ia includes ^? :i* actually invade ! body & fe$ ^u its tissues in/ead ( liv+ simply ^u swall[$ food4 ,x is difficult1 h[ev]1 to draw any %>p l9e sep>at+ ! two classes4 ,! bact]ia :i* cause diph!ria 7,fig4 #bh71 = in/ance1 d n really invade ! body4 ,!y gr[ 9 ! ?roat1 atta*$ to its walls1 & are conf9$ to ?is ext]nal location or to ! sup]ficial tissues4 ,?is bacillus is1 9 %ort1 only f\nd 9 ! m\? & ?roat1 & is practically conf9$ to ! s-call$ false membranes4 ,x nev] ent]s any ( ! tissues ( ! body1 al?\gh atta*$ to ! muc\s membrane4 ,x gr[s vigor\sly 9 ?is membrane1 & !re secretes or 9 "s way produces extremely viol5t poisons4 ,^! poisons are !n absorb$ by ! body & give rise to ! g5]al symptoms ( ! disease4 ,mu* ! same is true ( ! bacillus :i* causes tetanus or lockjaw 7,fig4 #bi74 ,?is bacillus is commonly inoculat$ into ! fle% ( ! victim by a w\nd made ) "s object :i* has be5 ly+ ^u ! e>? :]e ! bacillus lives4 ,! bacillus gr[s readily aft] be+ inoculat$1 b x is localiz$ at ! po9t ( ! w\nd1 )\t invad+ ! tissue to any ext5t4 ,x produces1 h[ev]1 dur+ its gr[? sev]al poisons :i* h be5 sep>at$ & /udi$4 ,among !m are "s ( ! mo/ viol5t poisons ( :i* we h any k4 ,:ile ! bacillus gr[s 9 ! tissues ar\nd ! w\nd x secretes ^! poisons1 :i* are !n absorb$ by ! body g5]ally4 ,_! poison+ effects produce ! viol5t symptoms ( ! disease4 ,( mu* ! same nature is ,asiatic *ol]a4 ,?is is caus$ by a bacillus :i* is able to gr[ rapidly 9 ! inte/9es1 fe$+ p]haps 9 "p on ! food 9 ! inte/9es & p]haps 9 "p ^u ! body secretions4 ,to a slight ext5t also x appe>s to be able to invade ! tissues ( ! body1 = ! bacilli are f\nd 9 ! walls ( ! inte/9es4 ,b x is n a prop] p>asite1 & ! fatal disease x produces is ! result ( ! absorption ( ! poisons secret$ 9 ! inte/9es4 ,x is b a /ep f ?is to ! true p>asites4 ,typhoid fev]1 = example1 is a disease produc$ by bact]ia :i* gr[ 9 ! inte/9es1 b :i* also invade ! tissues m ext5sively ?an ! *ol]a g]ms 7,fig4 #cj74 ,!y d n invade ! body g5]ally1 h[ev]1 b become some:at localiz$ 9 special gl&s l ! liv]1 ! sple51 etc4 ,ev5 "h !y d n appe> to f9d a v fav\rable condition1 = !y d n gr[ ext5sively 9 ^! places4 ,!y are likely to be f\nd 9 ! sple5 9 small gr\ps or c5tres1 b n g5]ally di/ribut$ ?r\gh x4 ,:]ev] !y gr[ !y produce poison1 :i* has be5 call$ typhotox9e1 & x is ?is poison *iefly :i* gives rise to ! fev]4 ,q a consid]able numb] ( ! pa?og5ic g]ms are1 l ! typhoid bacillus1 m or less conf9$ to special places4 ,in/ead ( di/ribut+ !mselves ?r\gh ! body aft] !y f9d entrance1 !y are re/rict$ to special organs4 ,! mo/ common example ( a p>asite ( ?is sort is ! tub]culosis bacillus1 ! cause ( consumption1 scr(ula1 :ite swell+1 lupus1 etc4 7,fig4 #ca74 ,al?\gh ?is bacillus is v common & is able to attack almo/ any organ 9 ! body1 x is usually v re/rict$ 9 gr[?4 ,x may become localiz$ 9 a small gl&1 a s+le jo9t1 a small spot 9 ! lungs1 or 9 ! gl&s ( ! mes5t]y1 ! o!r p>ts ( ! body rema9+ free f infection4 ,n infrequ5tly ! :ole tr\ble is ?us conf9$ to su* a small locality t no?+ s]i\s results4 ,b 9 o!r in/ances ! bacilli may aft] a "t sl[ly or rapidly di/ribute !mselves f ^! c5tres1 attack+ m & m ( ! body until p]haps fatal results foll[ 9 ! end4 ,?is disease is !re=e commonly ( v sl[ progress4 ,aga91 we h /ill o!r p>asites :i* are n ?us conf9$1 b :i*1 z soon z !y ent] ! body1 produce a g5]al infection1 attack+ ! blood & p]haps ne>ly all tissues simultane\sly4 ,! mo/ typical example ( ?is sort is an?rax or malignant pu/ule1 a disease =tunately r>e 9 man 7,fig4 #cb74 ,"h ! bacilli multiply 9 ! blood1 & v soon a g5]al & fatal infection ( ! :ole body arises1 result+ f ! abundance ( ! bacilli ev]y:]e4 ,"s ( ! obscure diseases kn[n z blood poison+ appe> to be ( ! same g5]al nature1 ^! diseases result+ f a v g5]al invasion ( ! :ole body by c]ta9 pa?og5ic bact]ia4 ,9 g5]al1 !n1 we see t ! s-call$ g]m diseases result f ! action ^u ! body ( poisons produc$ by bact]ial gr[?4 ,diff]5ces 9 ! nature ( ^! poisons produce diff]5ces 9 ! "* ( ! disease1 & diff]5ces 9 ! p>asitic p[]s ( ! diff]5t species ( bact]ia produce wide diff]5ces 9 ! c\rse ( ! diseases & _! relation to ext]nal ph5om5a4 ,,:at ,,diseases ,,are ,,due ,,to ,,bact]ia8 ,x is1 ( c\rse1 an extremely important matt] to det]m9e to :at ext5t human diseases are caus$ by bact]ia4 ,x is n easy1 nor inde$ possible1 to d ?is to-day ) accuracy4 ,x is no easy matt] to prove t any p>ticul> disease is caus$ by bact]ia4 ,to d ?is x is necess>y to f9d "s p>ticul> bact]ium pres5t 9 all cases ( ! disease2 to f9d "s me?od ( gett+ x to gr[ outside ! body 9 culture m$ia2 to demon/rate its abs5ce 9 heal?y animals1 or heal?y human individuals if x be a human disease2 &1 f9ally1 to reproduce ! disease 9 heal?y animals by inoculat+ !m ) ! bact]ium4 ,all ( ^! /eps ( pro( pres5t difficulties1 b especially ! la/ "o4 ,9 ! /udy ( animals x is comp>atively easy to reproduce a disease by inoculation4 ,b exp]im5ts ^u man are commonly impossible1 & 9 ! case ( human diseases x is frequ5tly v difficult or impossible to obta9 ! f9al te/ ( ! matt]4 ,aft] f9d+ a specific bact]ium associat$ ) a disease1 x is usually possible to exp]im5t ) x fur!r ^u animals only4 ,b "s human diseases d n attack animals1 & 9 ! case ( diseases t may be giv5 to animals x is frequ5tly unc]ta9 :e!r ! disease produc$ 9 ! animal by su* inoculation is id5tical ) ! human disease 9 "q1 ow+ to ! diff]5ce ( symptoms 9 ! diff]5t animals4 ,z a consequ5ce1 ! pro( ( ! g]m nature ( diff]5t diseases v>ies all ! way f absolute demon/ration to m]e suspicion4 ,to give a complete & correct li/ ( ! diseases caus$ by bact]ia1 or to give a li/ ( ! bact]ia species pa?og5ic to man1 is !re=e at pres5t impossible4 ,! difficulty ( giv+ su* a li/ is r5d]$ great] f ! fact t we h 9 rec5t ye>s le>n$ t ! same species ( pa?og5ic bact]ium may produce diff]5t results "u diff]5t conditions4 ,:5 ! subject ( g]m disease 0 fir/ /udi$ & ! connection betwe5 bact]ia & disease 0 fir/ demon/rat$1 x 0 ?\ght t ea* p>ticul> species ( pa?og5ic bact]ia produc$ a s+le def9ite disease2 & conv]sely1 ea* g]m disease 0 suppos$ to h its own def9ite species ( bact]ium z its cause4 ,rec5t /udy has %[n1 h[ev]1 t ?is is n :olly true4 ,x is true t "s diseases d h su* a def9ite relation to def9ite bact]ia4 ,! an?rax g]m1 = example1 w always produce an?rax1 no matt] :]e or h[ x is inoculat$ into ! body4 ,s1 also1 9 q a numb] ( o!r cases di/9ct specific bact]ia are associat$ ) di/9ct diseases4 ,b1 on ! o!r h&1 !re are "s pa?og5ic bact]ia :i* are n s def9ite 9 _! action1 & produce diff]5t results 9 accordance ) circum/ances1 ! effect v>y+ bo? ) ! organ attack$ & ) ! condition ( ! individual4 ,= in/ance1 a consid]able numb] ( diff]5t types ( blood poison+1 septicaemia1 pyaemia1 gangr5e1 inflammation ( w\nds1 or =mation ( pus f slight sk9 w\nds--inde$1 a ho/ ( miscellane\s tr\bles1 rang+ all ! way f a slight pus =mation to a viol5t & sev]e blood poison+--all appe> to be caus$ by bact]ia1 & x is impossible to make out any def9ite species associat$ ) ! diff]5t types ( ^! tr\bles4 ,!re are ?ree common =ms ( s-call$ pus cocci1 & ^! are f\nd almo/ indiscrim9ately ) v>i\s types ( inflammatory tr\bles4 ,moreov]1 ^! species ( bact]ia are f\nd ) almo/ absolute con/ancy 9 & ar\nd ! body1 ev5 9 heal?4 ,!y are on ! clo?+1 on ! sk91 9 ! m\? & alim5t>y canal4 ,"h !y exi/1 commonly do+ no h>m4 ,!y h1 h[ev]1 ! p[] ( do+ injury if by *ance !y get into w\nds4 ,b _! p[] ( do+ injury v>ies bo? ) ! condition ( ! individual & ) v>iations 9 ! bact]ia !mselves4 ,if ! individual is 9 a good condition ( heal? ^! bact]ia h little p[] ( injur+ him ev5 :5 !y d get into su* w\nds1 :ile at times ( feeble vitality !y may d mu* m injury1 & take ! occasion ( any little cut or bruise to ent] "u ! sk9 & give rise to inflammation & pus4 ,"s p w develop slight abscesses or slight inflammations :5ev] ! sk9 is bruis$1 :ile ) o!rs su* bruises or cuts heal at once )\t tr\ble4 ,bo? are d\btless subject to ! same *ance ( infection1 b ! "o resi/s1 :ile ! o!r does n4 ,9 common p>lance1 we say t su* a t5d5cy to abscesses indicates a bad condition ( ! blood--a phrase :i* means no?+4 ,fur!r1 we f9d t ! same species ( bact]ium may h v>y+ p[]s ( produc+ disease at diff]5t times4 ,"s species are univ]sal inhabitants ( ! alim5t>y canal & are ord9>ily h>mless1 :ile "u o!r conditions ( unkn[n "* !y invade ! tissues & give rise to a s]i\s & p]haps fatal disease4 ,we may ?us recognise "s bact]ia :i* may be comp>$ to =eign invad]s1 :ile o!rs are dome/ic enemies4 ,! =m]1 l ! typhoid bacillus1 always produce tr\ble :5 !y succe$ 9 ent]+ ! body & f9d+ a foo?old4 ,! latt]1 l ! normal inte/9al bacilli1 are always pres5t b commonly h>mless1 only "u special conditions becom+ tr\blesome4 ,all ?is %[s t !re are o!r factors 9 det]m9+ ! c\rse ( a disease1 or ev5 ! exi/5ce ( a disease1 ?an ! simple pres5ce ( a peculi> species ( pa?og5ic bact]ium4 ,f ! facts j /at$ x w be evid5t t any li/ ( g]m diseases w be r unc]ta94 ,/ill1 ! /udies ( ! la/ tw5ty ye>s or m h disclos$ "s def9ite relations ( bact]ia & disease1 & a li/ ( ! diseases m or less def9itely associat$ ) di/9ct species ( bact]ia is ( int]e/4 ,su* a li/1 includ+ only well-kn[n diseases1 is z foll[s3 ,"n ( disease4 ,"n ( bact]ium produc+ ! disease4 ,an?rax 7,malignant pu/ule74 ,bacillus an?racis4 ,*ol]a4 ,spirillum *ol]a3 asiaticae ,cr\p\s pneumonia4 ,micrococcus pneumonia cr\posa4 ,diph!ria4 ,bacillus diph!ria4 ,gl&]s4 ,bacillus mallei4 ,gonorrhoea4 ,micrococcus gonorrhaeae ,influ5za4 ,bacillus ( influ5za4 ,leprosy4 ,bacillus leprae4 ,relaps+ fev]4 ,spirillum ,ob]mei]i4 ,tetanus 7lockjaw74 ,bacillus tetani4 ,tub]culosis 7includ+ consumption1 scr(ula1 etc47 ,bacillus tub]culosis4 ,typhoid fev]4 ,bacillus typhi abdom9alis4 ,v>i\s w\nd infections1 includ+ septicaemia1 pyaemia1 acute abscesses1 ulc]s1 erysipelas1 etc41 are produc$ by a few =ms ( micrococci1 resembl+ ea* o!r 9 _m po9ts b diff]+ slightly4 ,!y are f\nd almo/ indiscrim9ately 9 any ( ^! w\nd infections1 & none ( !m appe>s to h any def9ite relation to any special =m ( disease unless x be ! micrococcus ( erysipelas4 ,! common pus micrococci are gr\p$ "u ?ree species1 ,/aphylococcus pyog5es aureus1 ,/aphylococcus pyog5es1 & ,/reptococcus pyog5es4 ,^! ?ree are ! mo/ common1 b o!rs are occasionally f\nd4 ,9 addition to ^!1 :i* may be reg>d$ z demon/rat$1 ! foll[+ diseases are ) m or less c]ta9ty reg>d$ z caus$ by di/9ct specific bact]ia3 ,bron*itis1 endoc>ditis1 measles1 :oop+-c\gh1 p]itonitis1 pneumonia1 syphilis4 ,/ill ano!r li/ might be giv5 ( diseases ^: g5]al nature indicates t !y are caus$ by bact]ia1 b 9 connection ) :i* no di/9ct bact]ium has yet be5 f\nd4 ,z might be expect$ also1 a l>g] li/ ( animal diseases has be5 demon/rat$ to be caus$ by ^! organisms4 ,9 addition1 q a numb] ( species ( bact]ia h be5 f\nd 9 su* mat]ial z faeces1 putrefy+ blood1 etc41 :i* h be5 %[n by exp]im5t to be capable ( produc+ diseases 9 animals1 b 9 reg>d to :i* we h no evid5ce t !y ev] d produce actual disease "u any normal conditions4 ,^! may contribute1 p]haps1 to ! tr\bles aris+ f poison\s foods1 b c n be reg>d$ z disease g]ms prop]4 ,,v>iability ,,( ,,pa?og5ic ,,p[]s4 ,z has already be5 /at$1 our ideas ( ! relation ( bact]ia to disease h und]gone q a *ange s9ce !y 7 fir/ =mulat$1 & we recognise o!r factors influ5c+ disease besides ! actual pres5ce ( ! bact]ium4 ,^! we may briefly consid] "u two heads1 viz41 v>iation 9 ! bact]ium1 & v>iation 9 ! susceptibility ( ! individual4 ,! fir/ w require only a brief consid]ation4 ,t ! same species ( pa?og5ic bact]ia at diff]5t times v>ies 9 its p[]s to produce disease has long be5 kn[n4 ,v>i\s conditions are kn[n to affect ?us ! virul5ce ( bact]ia4 ,! bacillus :i* is suppos$ to give rise to pneumonia loses its p[] to produce ! disease aft] hav+ be5 cultivat$ = a %ort "t 9 ord9>y culture m$ia 9 ! laboratory4 ,?is is easily und]/ood ^u ! sugge/ion t x is a p>asitic bacillus & does n ?rive except "u p>asitic conditions4 ,its pa?og5ic p[]s c sometimes be re/or$ by pass+ x aga9 ?r\gh "s susceptible animal4 ,"o ( ! mo/ viol5t pa?og5ic bact]ia is t :i* produces an?rax1 b ?is loses its pa?og5ic p[]s if x is cultivat$ = a consid]able p]iod at a high temp]ature4 ,! micrococcus :i* causes f[l *ol]a loses its p[] if x be cultivat$ 9 common culture m$ia1 c>e be+ tak5 to all[ sev]al days to elapse betwe5 ! successive inoculations into new culture flasks4 ,mo/ pa?og5ic bact]ia c 9 "s way be s treat$ z to suff] a dim9ution or complete loss ( _! p[]s ( produc+ a fatal disease4 ,on ! o!r h&1 o!r conditions w cause an increase 9 ! virul5ce ( a pa?og5ic g]m4 ,! virus :i* produces hydrophobia is increas$ 9 viol5ce if x is inoculat$ into a rabbit & subsequ5tly tak5 f ! rabbit = fur!r inoculation4 ,! f[l *ol]a micrococcus1 :i* has be5 weak5$ z j m5tion$1 may be re/or$ to its orig9al viol5ce by inoculat+ x into a small bird1 l a sp>r[1 & inoculat+ a second bird f ?is4 ,a few su* inoculations w make x z active z ev]4 ,^! v>iations d\btless exi/ among ! species 9 ,nature z well z 9 artificial cultures4 ,! bact]ia :i* produce ! v>i\s w\nd infections & abscesses1 etc41 appe> to v>y "u normal conditions f a type capable ( produc+ viol5t & fatal blood poison+ to a type produc+ only a simple abscess1 or ev5 to a type t is entirely innocu\s4 ,x is ?is factor1 d\btless1 :i* 9 a l>ge measure det]m9es ! sev]ity ( any epidemic ( a bact]ial contagi\s disease4 ,,susceptibility ,,( ,,! ,,individual4 ,! v great modification ( our e>ly views has affect$ our ideas z to ! p[] :i* individuals h ( resi/+ ! invasion ( pa?og5ic bact]ia4 ,x has f ! fir/ be5 und]/ood t "s individuals are m susceptible to disease ?an o!rs1 & 9 attempt+ to det]m9e ! significance ( ?is fact _m valuable & int]e/+ discov]ies h be5 made4 ,aft] ! exposure to ! disease !re foll[s a p]iod ( "s l5g? 9 :i* !re are no disc]nible effects4 ,?is is foll[$ by ! onset ( ! disease & its developm5t to a crisis1 &1 if ?is be pass$1 by a recov]y4 ,! g5]al c\rse ( a g]m disease is divid$ into ?ree /ages3 ! /age ( incubation1 ! developm5t ( ! disease1 & ! recov]y4 ,! susceptibility ( ! body to a disease may be be/ consid]$ "u ! ?ree heads ( ,invasion1 ,resi/ance1 ,recov]y4 ,means ( ,invasion4--,9 ord] t a g]m disease %\ld arise 9 an individual1 x is fir/ necess>y t ! special bact]ium :i* causes ! disease %\ld get into ! body4 ,!re are sev]al *annels ?r\gh :i* bact]ia c ?us f9d entrance2 ^! are ?r\gh ! m\?1 ?r\gh ! nose1 ?r\gh ! sk91 & occasionally ?r\gh excretory ducts4 ,^? :i* come ?r\gh ! m\? come ) ! food or dr9k :i* we swall[2 ^? :i* ent] ?r\gh ! nose mu/ be trac$ to ! air2 & ^? :i* ent] ?r\gh ! sk9 come 9 mo/ cases ?r\gh contact ) "s infect$ object1 su* z direct contact ) ! body ( an infect$ p]son or 8 clo?+ or "s objects he has h&l$1 etc4 ,occasionally1 p]haps1 ! bact]ia may get into ! sk9 f ! air1 b ?is is c]ta9ly uncommon & conf9$ to a few diseases4 ,!re are "h two facts ( ! utmo/ importance = e "o to und]/&3 fir/1 t ! *ance ( disease bact]ia be+ c>ri$ to u ?r\gh ! air is v slight & conf9$ to a few diseases1 su* z smallpox1 tub]culosis1 sc>let fev]2 etc41 &1 secondly1 t ! un9jur$ sk9 & ! un9jur$ muc\s membrane also is almo/ a sure protection aga9/ ! invasion ( ! bact]ia4 ,if ! sk9 is :ole1 )\t bruises or cuts1 bact]ia c seldom1 if ev]1 f9d passage ?r\gh x4 ,^! two facts are ( ! utmo/ importance1 s9ce ( all s\rces ( infection we h ! lea/ p[] to gu>d aga9/ infection ?r\gh ! air1 & s9ce ( all means '( entrance we c gu>d ! sk9 ) ! greate/ difficulty4 ,we c easily r5d] food free f pa?og5ic bact]ia by heat+ x4 ,! mat]ial we dr9k c simil>ly be r5d]$ h>mless1 b we c n by any kn[n means avoid brea?+ air1 nor is !re any kn[n me?od ( dis9fect+ ! air1 & x is impossible = ^? :o h any?+ to d ) sick p]sons to avoid entirely hav+ contact ei!r ) ! pati5t or ) infect$ clo?+ or ut5sils4 ,f ! facts "h giv5 x w be se5 t ! individual's susceptibility to disease produc$ by p>asitic bact]ia w dep5d ^u 8 habits ( cleanl9ess1 8 c>e 9 h&l+ infecti\s mat]ial1 or c>e 9 cleans+ ! h&s aft] su* h&l+1 ^u 8 habit ( eat+ food cook$ or raw1 & ^u ! condition ( 8 sk9 & muc\s membranes1 s9ce any k9d ( bruises w increase susceptibility4 ,slight ailm5ts1 su* z colds1 :i* inflame ! muc\s membrane1 w decrease its resi/+ p[] & r5d] ! individual m susceptible to ! entrance ( any pa?og5ic g]ms %\ld !y happ5 to be pres5t4 ,sores 9 ! m\? or decay$ tee? may 9 ! same way be prom95t factors 9 ! individual's susceptibility4 ,?us q a numb] ( purely physical factors may contribute to an individual's susceptibility4 ,resi/+ ,p[] ( ! ,body4--,ev5 aft] ! bact]ia get into ! body x is by no means c]ta9 t !y w give rise to disease1 = !y h n[ a battle to fight be=e !y c be sure ( hold+ _! own4 ,x is n[1 inde$1 t ! actual conflict betwe5 ! p[]s ( ! body & ^! microscopic invad]s beg9s4 ,aft] !y h f\nd entrance into ! body ! bact]ia h array$ aga9/ !m /rong resi/+ =ces ( ! human organism1 endeav\r+ to de/roy & expel !m4 ,_m ( !m are rapidly kill$1 & sometimes !y are all de/roy$ )\t be+ able to ga9 a foo?old4 ,9 su* cases1 ( c\rse1 no tr\ble results4 ,9 o!r cases ! body fails to ov]come ! p[]s ( ! invad]s & !y ev5tually multiply rapidly4 ,9 ?is /ruggle ! success ( ! invad]s is n necess>ily a matt] ( numb]s4 ,!y are simply /ruggl+ to ga9 a position 9 ! body1 :]e !y c fe$ & gr[4 ,a few individuals may be entirely suffici5t to seize su* a foo?old1 & !n ^! by multiply+ may soon become indef9itely num]\s4 ,to protect itself1 !re=e1 ! human body mu/ de/roy e individual bact]ium1 or at lea/ r5d] !m all incapable ( gr[?4 ,_! m>vell\s reproductive p[]s give ! bact]ia an advantage 9 ! battle4 ,on ! o!r h&1 x takes "t ev5 = ^! rapidly multiply+ be+s to become suffici5tly num]\s to d injury4 ,!re is ?us an int]val aft] _! p5etration into ! body :5 ^! invad]s are weak 9 numb]s4 ,dur+ ?is int]val--! p]iod ( incubation--! body may organize a resi/ance suffici5t to expel !m4 ,we d n z yet ?or\ghly und]/& ! =ces :i* ! human organism is able to array aga9/ ^! invad+ foes4 ,"s ( its me?ods ( def5ce are1 h[ev]1 already intelligible to u1 & we "k en\gh1 at all ev5ts1 to give u an idea ( ! int5sity ( ! conflict t is go+ on1 & ( ! vigor\s & p[]ful =ces :i* ! human organism is able to br+ aga9/ its invad+ enemies4 ,9 ! fir/ place1 we notice t a majority ( bact]ia are utt]ly unable to gr[ 9 ! human body ev5 if !y d f9d entrance4 ,!re are kn[n to bact]iologi/s to-day _m hundr$s1 ev5 ?\s&s ( species1 b ! va/ majority ( ^! f9d 9 ! human tissues conditions s ho/ile to _! life t !y are utt]ly unable to gr[ !re94 ,human fle% or human blood w furni% excell5t food = !m if ! individual be dead1 b liv+ human fle% & blood 9 "s way ex]ts a repress+ influ5ce ^u !m :i* is fatal to ! gr[? ( a va/ majority ( species4 ,"s few species1 h[ev]1 are n ?us de/roy$ by ! ho/ile ag5cies ( ! tissues ( ! animal1 b are capable ( gr[+ & multiply+ 9 ! liv+ body4 ,^! alone are :at con/itute ! pa?og5ic bact]ia1 s9ce1 ( c\rse1 ^! are ! only bact]ia :i* c produce disease by gr[+ 9 ! tissues ( an animal4 ,! fact t ! va/ majority ( bact]ia c n gr[ 9 ! liv+ organism %[s cle>ly en\gh t !re are "s conditions exi/+ 9 ! liv+ tissue ho/ile to bact]ial life4 ,!re c be little d\bt1 moreov]1 t x is ^! same ho/ile conditions1 :i* enable ! body to resi/ ! attack ( ! pa?og5ic species 9 cases :]e resi/ance is successfully made4 ,:at are ! =ces array$ aga9/ ^! invad]s8 ,! ess5tial nature ( ! battle appe>s to be a production ( poisons & c\nt] poisons4 ,x appe>s to be an und\bt$ fact t ! fir/ /ep 9 repell+ ^! bact]ia is to flood !m ) c]ta9 poisons :i* *eck _! gr[?4 ,9 ! blood & lymph ( man & o!r animals !re are pres5t c]ta9 products :i* h a direct delet]i\s influ5ce ^u ! gr[? ( micro-organisms4 ,! exi/5ce ( ^! poisons is und\bt$1 _m an exp]im5t hav+ directly atte/$ to _! pres5ce 9 ! blood ( animals4 ,( _! nature we "k v little1 b ( _! repress+ influ5ce ^u bact]ial gr[? we are sure4 ,!y h be5 nam$ alex9es1 & !y are produc$ 9 ! liv+ tissue1 al?\gh z to ! me?od ( _! production we are 9 ignorance4 ,by ! aid ( ^! poisons ! body is able to prev5t ! gr[? ( ! va/ majority ( bact]ia :i* get into its tissues4 ,ord9>y micro-organisms are kill$ at once1 = ^! alex9es act z antiseptics1 & common bact]ia c no m gr[ 9 ! liv+ body ?an !y c\ld 9 a solution conta9+ o!r poisons ,?us ! body has a p]fect protection aga9/ ! majority ( bact]ia4 ,! great ho/ ( species :i* are f\nd 9 wat]1 milk1 air1 9 our m\?s or cl++ to our sk91 & :i* are almo/ omnipres5t 9 ,nature1 are capable ( gr[+ well en\gh 9 ord9>y lifeless organic foods1 b j z soon z !y succe$ 9 f9d+ entrance into liv+ human tissue _! gr[? is *eck$ at once by ^! antiseptic ag5ts :i* are p\r$ ^u !m4 ,su* bact]ia are !re=e n pa?og5ic g]ms1 & n s\rces ( tr\ble to human heal?4 ,!re are1 on ! o!r h&1 a few species ( bact]ia :i* may be able to reta9 _! lodgm5t 9 ! body m spite ( ?is attempt ( ! individual to get rid ( !m4 ,^!1 ( c\rse1 con/itute ! pa?og5ic species1 or s call$ disease g]ms4 ,only su* species z c ov]come ?is fir/ resi/ance c be disease g]ms1 = !y alone c reta9 _! foo?old 9 ! body4 ,b h[ d ^! species ov]come ! poisons1 :i* kill ! o!r h>mless bact]ia8 ,!y1 z well z ! h>mless =ms1 f9d ^! alex9es injuri\s to _! gr[?1 b 9 "s way !y are able to c\nt]act ! poisons4 ,9 ?is g5]al discussion ( poisons we are deal+ ) a subject :i* is some:at obscure1 b app>5tly ! pa?og5ic bact]ia are able to ov]come ! alex9es ( ! body by produc+ 9 _! turn c]ta9 o!r products :i* neutralize ! alex9es1 ?us annull+ _! action4 ,^! pa?og5ic bact]ia1 :5 !y get into ! body1 give rise at once to a gr\p ( bodies :i* h be5 nam$ lys9es4 ,^! lys9es are z my/]i\s to u z ! alex9es1 b !y neutralize ! effect ( ! alex9es & ?us ov]come ! resi/ance ! body (f]s to bact]ial gr[? ,! invad]s c n[ multiply rapidly en\gh to get a la/+ foo?old 9 ! body & !n soon produce ! abnormal symptoms :i* we call disease ,pa?og5ic bact]ia ?us diff] f ! non-pa?og5ic bact]ia prim>ily 9 ?is p[] ( secret+ products :i* c neutralize ! ord9>y effects ( ! alex9es1 & s ov]come ! body's normal resi/ance to _! p>asitic life4 ,ev5 if ! bact]ia d ?us ov]come ! alex9es ! battle is n yet ov]1 = ! individual has ano!r me?od ( def5ce :i* is n[ br\ght into activity to *eck ! gr[? ( ! invad+ organisms4 ,?is second me?od ( resi/ance is by means ( a s]ies ( active cells f\nd 9 ! blood1 kn[n z :ite blood-corpuscles 7,fig4 #cc a1 b74 ,!y are m9ute bits ( protoplasm pres5t 9 ! blood & lymph 9 l>ge quantities4 ,!y are active cells1 capable ( locomotion & able to crawl out ( ! blood-vessels ,n infrequ5tly !y are f\nd to take into _! bodies small objects ) :i* !y come 9 contact4 ,"o ( _! duties is ?us to engulf m9ute irritat+ bodies :i* may be 9 ! tissues1 & to c>ry !m away = excretion4 ,!y ?us act z scav5g]s ,^! corpuscles c]ta9ly h "s ag5cy 9 w>d+ (f ! attacks ( pa?og5ic bact]ia ,v commonly !y collect 9 great numb]s 9 ! region ( ! body :]e invad+ bact]ia are f\nd4 ,su* invad+ bact]ia exi/ ^u !m a /rong attraction1 & ! corpuscles leave ! blood-vessels & sometimes =m a solid phalanx completely surr\nd+ ! invad+ g]ms4 ,_! collection at ^! po9ts may make itself se5 ext]nally by ! ph5om5on we call inflammation4 ,!re is no "q t ! corpuscles engage 9 conflict ) ! bact]ia :5 !y ?us surr\nd !m4 ,!re has be5 n a little dispute1 h[ev]1 z to ! me?od by :i* !y c>ry on ! conflict4 ,x has be5 held by "s t ! corpuscles actually take ! bact]ia into _! bodies1 swall[ !m1 z x 71 & subsequ5tly dige/ !m 7,fig4 #cc c1 d1 e74 ,?is idea gave rise to ! !ory ( phagocytosis1 & ! corpuscles 7 consequ5tly nam$ phagocytes4 ,! /udy ( sev]al ye>s has1 h[ev]1 made x probable t ?is is n ! ord9>y me?od by :i* ! corpuscles de/roy ! bact]ia4 ,accord+ to our pres5t k ! me?od is a *emical "o4 ,^! cells1 :5 !y ?us collect 9 quantities ar\nd ! invad]s1 appe> to secrete f _! own bodies c]ta9 injuri\s products :i* act ^u ! bact]ia mu* z d ! alex9es already m5tion$4 ,^! new bodies h a decid$ly injuri\s effect ^u ! multiply+ bact]ia2 !y rapidly *eck _! gr[?1 &1 act+ 9 union ) ! alex9es1 may p]haps entirely de/roy !m4 ,aft] ! bact]ia are ?us kill$1 ! :ite blood-corpuscles may load !mselves ) _! dead bodies & c>ry !m away 7,fig4 #cc d1 e74 ,sometimes !y pass back into ! blood /ream & c>ry ! bact]ia to v>i\s p>ts ( ! body = elim9ation4 ,n infrequ5tly ! :ite corpuscles die 9 ! conte/1 & !n may accumulate 9 ! =m ( pus & make _! way ?r\gh ! sk9 to be dis*>g$ directly4 ,! battle betwe5 ^! phagocytes & ! bact]ia goes on vigor\sly4 ,if 9 ! end ! phagocytes prove too /rong = ! invad]s1 ! bact]ia are gradually all de/roy$1 & ! attack is repell$4 ,"u ^! circum/ances ! individual commonly kn[s no?+--( ! matt]4 ,?is conflict has tak5 place entirely )\t any consci\sness on 8 "p1 & he may n ev5 "k t he has be5 expos$ to ! attack ( ! bact]ia4 ,9 o!r cases ! bact]ia prove too /rong = ! phagocytes4 ,!y multiply too rapidly1 & sometimes !y produce secretions :i* actually drive ! phagocytes away4 ,commonly1 z already notic$1 ! corpuscles are attract$ to ! po9t ( invasion1 b 9 "s cases1 :5 a p>ticul>ly deadly & vigor\s species ( bact]ia invades ! body1 ! secretions produc$ by !m are s p[]ful z actually to drive ! corpuscles away4 ,"u ^! circum/ances ! invad+ ho/s h a *ance to multiply unimp$$1 to di/ribute !mselves ov] ! body1 & ! disease rapidly foll[s z ! result ( _! poison+ action on ! body tissues4 ,x is pla91 !n1 t ! human body is n helpless 9 ! pres5ce ( ! bact]ia ( disease1 b t x is suppli$ ) p[]ful resi/ant =ces4 ,x mu/ n be suppos$1 h[ev]1 t ! outl9e ( ! action ( ^! =ces j giv5 is any?+ l a complete acc\nt ( ! matt]2 nor mu/ x be inf]r$ t ! resi/ance is 9 all respects exactly z outl9$4 ,! subject has only rec5tly be5 an object ( inve/igation1 & we are z yet 9 ! d>k 9 reg>d to _m ( ! facts4 ,! future may require u to modify to "s ext5t ev5 ! brief outl9e :i* has be5 giv54 ,b :ile we recognise ?is unc]ta9ty 9 ! details1 we may be assur$ ( ! g5]al facts4 ,! liv+ body has "s v efficaci\s resi/ant =ces :i* prev5t mo/ bact]ia f gr[+ )9 its tissues1 & :i* 9 l>ge measure may be reli$ ^u to drive out ! true pa?og5ic bact]ia4 ,^! resi/ant =ces are 9 "p associat$ ) ! productions ( body poisons1 & are 9 "p associat$ ) ! active p[]s ( special cells :i* h be5 call$ phagocytes4 ,! orig9 ( ! poisons & ! exact me?od ( action ( ! phagocytes we may well leave to ! future to expla94 ,^! resi/+ p[]s ( ! body w v>y ) conditions4 ,x is evid5t t !y are natural p[]s1 & !y w d\btless v>y ) ! g5]al condition ( vig\r ( ! individual4 ,robu/ heal?1 a body ^: p[]s are /rong1 well n\ri%$1 & vigor\s1 w pla9ly furni% ! conditions = ! greate/ resi/ance to bact]ial diseases4 ,"o ^: bodily activities are weak5$ by poor nutrition c (f] less resi/ance4 ,! "q :e!r "o %all suff] f a g]m disease is n simply ! "q :e!r he %all be expos$1 or ev5 ! "q :e!r ! bact]ia %all f9d entrance into 8 body4 ,x is equally dep5d5t ^u :e!r he has ! bodily vig\r to produce alex9es 9 prop] quantity1 or to summon ! phagocytes 9 suffici5t abundance & vig\r to w>d (f ! attack4 ,we may d mu* to prev5t disease by sanitation1 :i* aids 9 protect+ ! individual f attack2 b we mu/ n =get t ! o!r half ( ! battle is ( equal importance1 & h5ce we mu/ d all we c to /r5g!n ! resi/+ =ces ( ! organism4 ,,recov]y ,,f ,,g]m ,,diseases4 ,^! resi/+ =ces are n always suffici5t to drive (f ! invad]s4 ,! organisms may reta9 _! hold 9 ! body = a "t & ev5tually break d[n ! resi/ance4 ,aft] ?is !y may multiply unimp$$ & take entire possession ( ! body4 ,z !y become m num]\s _! poison\s products increase & beg9 to produce direct poison+ effects on ! body4 ,! incubation p]iod is ov] & ! disease comes on4 ,! disease n[ runs its c\rse4 ,x becomes commonly m & m sev]e until a crisis is rea*$4 ,!n1 unless ! poison+ is s sev]e t dea? occurs1 ! effects pass away & recov]y takes place4 ,b :y %\ld n a g]m disease be always fatal8 ,if ! bact]ia ?us take possession ( ! body & c gr[ !re1 :y d !y n always cont9ue to multiply until !y produce suffici5t poison to de/roy ! life ( ! individual8 ,su* fatal results d1 ( c\rse1 occur1 b 9 by f> ! l>g] proportion ( cases recov]y f9ally takes place4 ,pla9ly1 ! body mu/ h ano!r set ( resi/+ =ces :i* is conc]n$ 9 ! f9al recov]y4 ,al?\gh weak5$ by ! poison+ & suff]+ f ! disease1 x does n yield ! battle1 b some:at sl[ly organizes a new attack ^u ! invad]s4 ,= a "t ! multiply+ bact]ia h an unimp$$ c\rse & gr[ rapidly2 b f9ally _! fur!r increase is *eck$1 _! vig\r impair$1 & aft] ?is !y dim9i% 9 numb]s & are f9ally expell$ f ! body entirely4 ,( ! nature ( ?is new resi/ance b little is yet kn[n4 ,we notice1 9 ! fir/ place1 t commonly aft] su* a recov]y ! individual has decid$ly increas$ resi/ance to ! disease4 ,?is increas$ resi/ance may be v la/+1 & may be s consid]able z to give almo/ complete immunity f ! disease = _m ye>s1 or = life4 ,"o attack ( sc>let fev] gives ! individual great immunity = ! future4 ,on ! o!r h&1 ! resi/ance ?us d]iv$ may be v tempor>y1 z 9 ! case ( diph!ria4 ,b a c]ta9 am\nt ( resi/ance appe>s to be always acquir$4 ,?is p[] ( resi/+ ! activities ( ! p>asites seems to be increas$ dur+ ! progress ( ! disease1 &1 if x becomes suffici5t1 x f9ally drives (f ! bact]ia be=e !y h produc$ dea?4 ,aft] ?is1 recov]y takes place4 ,to :at ?is newly acquir$ resi/+ p[] is due is by no means cle> to bact]iologi/s1 al?\gh c]ta9 factors are already kn[n4 ,x appe>s beyond "q t 9 ! case ( c]ta9 diseases ! cells ( ! body aft] a "t produce sub/ances :i* s]ve z antidotes to ! poisons produc$ by ! bact]ia dur+ _! gr[? 9 ! body-antitox9es4 ,9 ! case ( diph!ria1 = in/ance1 ! g]ms gr[+ 9 ! ?roat produce poisons :i* are absorb$ by ! body & give rise to ! symptoms ( ! disease2 b aft] a "t ! body cells react1 & !mselves produce a c\nt] toxic body :i* neutralizes ! poison\s effect ( ! diph!ria poison4 ,?is sub/ance has be5 isolat$ f ! blood ( animals t h recov]$ f an attack ( diph!ria1 & has be5 call$ diph!ria antitox9e4 ,b ev5 ) ?is k ! recov]y is n fully expla9$4 ,?is antitox9e neutralizes ! effects ( ! diph!ria tox9e1 & !n ! body develops /r5g? to drive (f ! bact]ia :i* h obta9$ lodgm5t 9 ! ?roat4 ,h[ !y accompli% ?is latt] a*ievem5t we d n "k z yet4 ,! antitoxme develop$ simply neutralizes ! effects ( ! tox9e4 ,"s o!r =ce mu/ be at "w to get rid ( ! bact]ia1 a =ce :i* c only ex]t itself aft] ! poison+ effect ( ! poison is neutraliz$4 ,9 ^! cases1 !n1 ! recov]y is due1 fir/1 to ! developm5t 9 ! body ( ! natural antidotes to ! toxic poisons1 &1 second1 to "s o!r unkn[n =ce :i* drives (f ! p>asites4 ,^! facts are c]ta9ly surpris+4 ,if "o _h be5 ask$ to sugge/ ! lea/ likely !ory to expla9 recov]y f disease1 he c\ld h>dly h f\nd "o m unlikely ?an t ! body cells develop$ dur+ ! disease an antidote to ! poison :i* ! disease bact]ia 7 produc+4 ,nev]!less1 x is beyond "q t su* antidotes are =m$ dur+ ! c\rse ( ! g]m diseases4 ,x has n yet be5 %[n 9 all diseases1 & x w\ld be entirely too mu* to claim t ?is is ! me?od ( recov]y 9 all cases4 ,we may say1 h[ev]1 9 reg>d to bact]ial diseases 9 g5]al1 t aft] ! bact]ia ent] ! body at "s weak po9t !y h fir/ a battle to fight ) ! resi/+ p[]s ( ! body1 :i* appe> to be p>tly biological & p>tly *emical4 ,^! resi/+ p[]s are 9 _m cases entirely suffici5t to prev5t ! bact]ia f obta9+ a foo?old4 ,if ! invad+ ho/ ov]come ! resi/+ p[]s1 !n !y beg9 to multiply rapidly1 & take possession ( ! body or "s "p ( x4 ,!y cont9ue to gr[ until ei!r ! individual dies or some?+ occurs to *eck _! gr[?4 ,aft] ! individual develops ! r5ew$ p[]s ( *eck+ _! gr[?1 recov]y takes place1 & ! individual is !n1 because ( ^! r5ew$ p[]s ( resi/ance1 immune f a second attack ( ! disease = a v>iable l5g? ( "t4 ,?is1 9 ! m]e/ outl9e1 repres5ts ! relation ( bact]ial p>asites to ! human body ,b :ile ?is is a fair g5]al expression ( ! matt]1 x mu/ be recognis$ t diff]5t diseases diff] mu* 9 _! relations1 & no g5]al outl9e w apply to all ,!y diff] 9 _! me?od ( attack & 9 ! po9t ( attack4 ,n only d !y produce diff]5t k9ds ( poisons giv+ rise to diff]5t symptoms ( poison+2 n only d !y produce diff]5t results 9 diff]5t animals2 n only d ! diff]5t pa?og5ic species diff] mu* 9 _! p[] to develop s]i\s disease1 b ! diff]5t species are v p>ticul> z to :at species ( animal !y attack4 ,"s ( !m c live z p>asites 9 man alone2 "s c live z p>asites ^u man & ! m\se & a few o!r animals2 "s c live 9 v>i\s animals b n 9 man2 "s appe> to be able to live 9 ! field m\se1 b n 9 ! common m\se2 "s live 9 ! horse2 "s 9 birds1 b n 9 w>m-blood$ mammals2 :ile o!rs1 aga91 c live almo/ equally well 9 ! tissues ( a long li/ ( animals4 ,^? :i* c live z p>asites ^u man are1 ( c\rse1 especially relat$ to human disease1 & are ( p>ticul> int]e/ to ! physician1 :ile ^? :i* live 9 animals are 9 a simil> way ( int]e/ to vet]9>ians4 ,?us we see t p>asitic bact]ia %[ ! wide/ v>iations4 ,!y diff] 9 po9t ( attack1 9 me?od ( attack1 & 9 ! "p ( ! body :i* !y seize ^u z a nucleus = gr[?4 ,!y diff] 9 viol5ce & 9 ! "* ( ! poisons !y produce1 z well z 9 _! p[] ( ov]com+ ! resi/+ p[]s ( ! body4 ,!y diff] at diff]5t times 9 _! p[]s ( produc+ disease4 ,9 %ort1 !y %[ su* a l>ge numb] ( diff]5t me?ods ( action t no g5]al /atem5ts c be made :i* w apply univ]sally1 & no "o me?od ( gu>d+ aga9/ !m or 9 driv+ !m (f c be hop$ to apply to any ext5d$ li/ ( diseases4 ,,diseases ,,caus$ ,,by ,,o!r ,,organisms ,,?an ,,bact]ia4 ,al?\gh ! purpose ( ?is "w is to deal prim>ily ) ! bact]ial _w1 x w\ld h>dly be fitt+ to leave ! subject )\t "s ref]5ce to diseases caus$ by organisms :i* d n belong to ! gr\p ( bact]ia4 ,:ile mo/ ( ! s-call$ g]m diseases are caus$ by ! bact]ia :i* we h be5 /udy+ 9 ! previ\s *apt]s1 !re are "s ^: incit+ cause is to be f\nd among organisms belong+ to o!r gr\ps4 ,"s ( ^! are plants ( a high] organization ?an bact]ia1 b o!rs are und\bt$ly microscopic animals4 ,_! life habits are some:at diff]5t f ^? ( bact]ia1 & h5ce ! c\rse ( ! diseases is commonly diff]5t4 ,( ! diseases ?us produc$ by microscopic animals or by high] plants1 "o or two are ( importance en\gh to des]ve special m5tion "h4 ,mal>ia4--,! mo/ important ( ^! diseases is mal>ia 9 its v>i\s =ms1 & kn[n "u v>i\s names--*ills & fev]1 autumnal fev]1 etc4 ,?is disease1 s common almo/ ev]y:]e1 has be5 /udi$ by physicians & sci5ti/s = a long "t1 & _m h be5 ! causes assign$ to x4 ,at "o "t x 0 ?\ght to be ! result ( ! gr[? ( a bact]ium1 & a di/9ct bacillus 0 describ$ z produc+ x4 ,x has f9ally be5 %[n1 h[ev]1 to be caus$ by a microscopic organism belong+ to ! gr\p ( unicellul> animals1 & some:at closely relat$ to ! well-kn[n amoeba4 ,?is organism is %[n 9 ,fig4 #cd4 ,! :ole hi/ory ( ! mal>ial organism is n yet kn[n4 ,! foll[+ /atem5ts comprise ! mo/ important facts kn[n 9 reg>d to x1 & its relation to ! disease 9 man4 ,und\bt$ly ! mal>ial g]m has "s home outside ! human body1 b x is n yet v def9itely kn[n :at ?is ext]nal home is2 nor d we "k f :at s\rce ! human p>asite is d]iv$4 ,x appe>s probable t wat] s]ves 9 "s cases z its means ( transf]5ce to man1 & air 9 o!r cases4 ,f "s ext]nal s\rce x ga9s access to man & f9ds its way into ! blood4 ,"h x attacks ! r$ blood-corpuscles1 ea* mal>ial organism mak+ its way into a s+le "o 7,fig4 #cdj74 ,"h x n[ gr[s1 increas+ 9 size at ! exp5se ( ! sub/ance ( ! corpuscle4 ,z x becomes l>g] x becomes granul>1 & soon %[s a t5d5cy to sep>ate into a numb] ( irregul> masses4 ,f9ally x breaks up into _m m9ute bodies call$ spores4 ,^! bodies break out ( ! corpuscle & = a "t live a free life 9 ! blood4 ,aft] a "t !y make _! way into o!r r$ blood-corpuscles1 develop into new mal>ial amoeboid p>asites1 & repeat ! gr[? & sporulation4 ,?is process c app>5tly be repeat$ _m times )\t *eck4 ,^! organisms are ?us to be reg>d$ z p>asites ( ! r$ corpuscles4 ,x is1 ( c\rse1 easy to believe t an ext5sive p>asitism & de/ruction ( ! corpuscles w\ld be disa/r\s to ! heal? ( ! individual1 & ! sev]ity ( ! disease w dep5d ^u ! ext5t ( ! p>asitism4 ,correspond+ to ?is life hi/ory ( ! organism1 ! disease mal>ia is commonly *>act]iz$ by a decid$ int]mitt5cy1 p]iods ( *ill & fev] alt]nat+ ) p]iods ( int]mission 9 :i* ^! symptoms are abat$4 ,! p>oxysms ( ! disease1 *>act]iz$ by ! *ill1 occur at ! "t t ! spores are escap+ f ! blood-corpuscles & float+ 9 ! blood4 ,aft] !y h aga9 f\nd _! way into a blood-corpuscle ! fev] dim9i%es1 & dur+ _! gr[? 9 ! corpuscle until ! next sporulation ! individual has a re/ f ! m sev]e symptoms4 ,!re appe>s to be m ?an "o v>iety ( ! mal>ial organism1 ! diff]5t types diff]+ 9 ! l5g? ( "t x takes = _! gr[? & sporulation4 ,!re is "o v>iety1 ! mo/ common "o1 :i* requires two days = its gr[?1 ?us giv+ rise to ! p>oxysm ( ! disease ab\t once 9 =ty- eight h\rs2 ano!r v>iety appe>s to require ?ree days = its gr[?2 :ile /ill ano!r v>iety appe>s to be decid$ly irregul> 9 its p]iod ( gr[? & sporulation4 ,^! facts readily expla9 "s ( ! v>iations 9 ! disease4 ,c]ta9 o!r irregul>ities appe> to be due to a diff]5t cause4 ,m ?an "o brood ( p>asites may be 9 ! blood ( ! individual at ! same "t1 "o produc+ sporulation at "o "t & ano!r at a diff]5t "t4 ,su* a simultane\s gr[? ( two indep5d5t broods may pla9ly produce almo/ any k9d ( modification 9 ! regul>ity ( ! disease4 ,! mal>ial organism appe>s to be v s5sitive to qu99e1 a v small quantity be+ suffici5t to kill x4 ,^u ?is po9t dep5ds ! value ( qu99e z a m$ic9e4 ,if ! drug be pres5t 9 ! blood at ! "t :5 ! spores are set free f ! blood-corpuscle1 !y are rapidly kill$ by x be=e !y h a *ance to ent] ano!r corpuscle4 ,dur+ _! gr[? 9 ! corpuscle !y are f> less s5sitive to qu99e ?an :5 !y exi/ 9 ! free condition z spores1 & at ?is "t ! drug has little effect4 ,! mal>ial organism is an animal1 & c n be cultivat$ 9 ! laboratory by any artificial me?od yet devis$4 ,its :ole hi/ory is !re=e n kn[n4 ,x d\btless has "s home outside ! blood ( animals1 & v likely x may pass ?r\gh o!r /ages ( a metamorphosis 9 ! bodies ( o!r animals4 ,mo/ p>asitic animals h two or m ho/s ^u :i* !y live1 alt]nat+ f "o to ! o!r1 & t su* is ! case ) ! mal>ial p>asite is at lea/ probable4 ,b z yet bact]iologi/s h be5 unable to discov] any?+ v def9ite 9 reg>d to ! matt]4 ,until we c le>n some?+ 9 reg>d to its life outside ! blood ( man we c d little 9 ! way ( devis+ me?ods to avoid x4 ,mal>ia diff]s f mo/ g]m diseases 9 ! fact t ! organisms :i* produce x are n elim9at$ f ! body 9 any way4 ,9 mo/ g]m diseases ! g]ms are dis*>g$ f ! pati5t by secretions or excretions ( "s k9d1 & f ^! excretions may readily f9d _! way into o!r individuals4 ,! mal>ial organism is n dis*>g$ f ! body 9 any way1 & h5ce is n contagi\s4 ,if ! p>asite does pass "p ( its hi/ory 9 "s o!r animal ?an man1 !re mu/ be "s means by :i* x passes f man to its o!r ho/4 ,x has be5 sugge/$ t "s ( ! insects :i* fe$ ^u human blood may s]ve z ! second ho/ & become inoculat$ :5 fe$+ ^u su* blood4 ,?is has be5 demon/rat$ ) />tl+ success 9 reg>d to ! mosquito 7,anopheles71 "s inve/igators go+ s f> z to say t ?is is ! only way 9 :i* ! disease c be communicat$4 ,sev]al o!r microscopic animals occur z p>asites ^u man1 & "s ( !m are s def9itely associat$ ) c]ta9 diseases z to lead to ! belief t !y are ! cause ( ^! diseases4 ,! only "o ( v common occurr5ce is a species kn[n z ,amaeba coli1 :i* is f\nd 9 cases ( dys5t]y4 ,9 a c]ta9 type ( dys5t]y ?is organism is s univ]sally f\nd t !re is little d\bt t x is 9 "s v intimate way associat$ ) ! cause ( ! disease4 ,def9ite pro( ( ! matt] is1 h[ev]1 z yet want+4 ,on ! side ( plants1 we f9d t sev]al plants ( a high] organization ?an bact]ia may become p>asitic ^u ! body ( man & produce v>i\s types ( disease4 ,^! plants belong mo/ly to ! same gr\p z ! m\lds1 & !y are especially apt to attack ! sk94 ,!y gr[ 9 ! sk91 p>ticul>ly "u ! hair1 & may s5d _! ?readlike bran*es into "s ( ! subd]mal tissues4 ,?is produces irritation & inflammation ( ! sk91 result+ 9 tr\ble1 & mak+ sores difficult to heal4 ,s long z ! plant cont9ues to gr[1 ! sores1 ( c\rse1 c n be heal$1 & :5 ! organisms get into ! sk9 "u ! hair x is frequ5tly difficult to de/roy !m4 ,among ! diseases ?us caus$ are r+worm1 ?ru%1 alopecia1 etc4 ,,*apt] ,,vi4 ,,me?ods ,,( ,,combat+ ,,p>asitic ,,bact]ia4 ,! *ief advantage ( kn[+ ! cause ( disease is t x gives u a vantage gr\nd f :i* we may hope to f9d means ( avoid+ its evils4 ,! /udy ( m$ic9e 9 ! pa/ hi/ory ( ! _w has be5 almo/ purely empirical1 ) a v little ( sci5tific basis4 ,great hopes are n[ ent]ta9$ t ^! new facts w place ?is matt] ^u a m /rictly sci5tific f\ndation4 ,c]ta9ly 9 ! pa/ tw5ty-five ye>s1 s9ce bact]iology has be5 /udi$1 m has be5 done to solve problems connect$ ) disease ?an ev] be=e4 ,?is new k has be5 p>ticul>ly direct$ t[>d means ( avoid+ disease4 ,bact]iology has ?us f> borne fruit l>gely 9 ! l9e ( prev5tive m$ic9e1 al?\gh to a c]ta9 ext5t also along ! l9e ( curative m$ic9e4 ,?is *apt] w be devot$ to consid]+ h[ ! /udy ( bact]iology has contribut$ directly & indirectly to our p[] ( combat+ disease4 ,,prev5tive ,,m$ic9e4 ,9 ! /udy ( m$ic9e 9 ! pa/ c5turies ! only aim has be5 to discov] me?ods ( cur+ disease2 at ! pres5t "t a l>ge & increas+ am\nt ( /udy is devot$ to ! me?ods ( prev5t+ disease4 ,prev5tive m$ic9e is a developm5t ( ! la/ few ye>s1 & is bas$ almo/ :olly ^u our k ( bact]ia4 ,?is subject is ye>ly becom+ ( m importance4 ,=ew>n$ is =e>m$1 & x has be5 f\nd t to "k ! cause ( a disease is a long /ep t[>d avoid+ x4 ,z "s ( our contagi\s & epidemic diseases h be5 /udi$ 9 ! light ( bact]iological k1 x has be5 f\nd possible to det]m9e n only _! cause1 b also h[ infection is br\ght ab\t1 & consequ5tly h[ contagion may be avoid$4 ,"s ( ! results :i* h gr[n up s sl[ly z to be h>dly appreciat$ are really great triumphs4 ,= in/ance1 ! /udy ( bact]iology fir/ l$ u to suspect1 & !n demon/rat$1 t tub]culosis is a contagi\s disease1 & f ! "t t ?is 0 ?us prov$ !re has be5 a sl[1 b1 x is hop$1 a sure decl9e 9 ?is disease4 ,bact]iological /udy has %[n t ! s\rce ( *ol]a infection 9 cases ( rag+ epidemics is1 9 l>ge "p at lea/1 our dr9k+ wat]2 & s9ce ?is has be5 kn[n1 al?\gh *ol]a has twice invad$ ,europe1 & has be5 widely di/ribut$1 x has n obta9$ any /rong foo?old or giv5 rise to any s]i\s epidemic except 9 a few cases :]e its ravages c be trac$ to recognis$ c>elessness4 ,x is v significant to comp>e ! hi/ory ( ! *ol]a epidemics ( ! pa/ few ye>s ) ^? ( e>li] dates4 ,9 ! epidemics ( e>li] ye>s ! *ol]a swept ru?lessly ?r\gh communities )\t *eck4 ,9 ! la/ few ye>s1 al?\gh x has repeat$ly knock$ at ! doors ( _m ,european cities1 x has be5 commonly conf9$ to isolat$ cases1 except 9 a few in/ances :]e ^! facts conc]n+ ! relation to dr9k+ wat] 7 ignor$4 ,! /udy ( prev5tive m$ic9e is yet 9 its infancy1 b x has already accompli%$ mu*4 ,x has develop$ mod]n sy/ems ( sanitation1 has guid$ u 9 ! build+ ( hospitals1 giv5 rules = ! managem5t ( ! sick-room :i* l>gely prev5t contagion f pati5t to nurse2 x has told u :at diseases are contagi\s1 & 9 :at way2 x has told u :at s\rces ( contagion %\ld be suspect$ & gu>d$ aga9/1 & has ?us done v mu* to prev5t ! spread ( disease4 ,its value is se5 9 ! fact t !re has be5 a con/ant decrease 9 ! dea? rate s9ce mod]n ideas ( sanitation began to h any influ5ce1 & 9 ! fact t our g5]al epidemics are less sev]e ?an 9 =m] ye>s1 z well z 9 ! fact t m p escape ! diseases :i* 7 9 =m] times almo/ univ]sal4 ,! /udy ( prev5tive m$ic9e takes into view sev]al factors1 all connect$ ) ! me?od & means ( contagion4 ,!y are ! foll[+3 ,! ,s\rce ( ,infecti\s ,mat]ial4--t has be5 le>n$ t = mo/ diseases ! infecti\s mat]ial comes f individuals suff]+ ) ! disease1 & t except 9 a few cases1 l mal>ia1 we mu/ always look to individuals suff]+ f disease = all s\rces ( contagion4 ,x is f\nd t pa?og5ic bact]ia are 9 all ^! cases elim9at$ f ! pati5t 9 "s way1 ei!r f ! alim5t>y canal or f sk9 secretions or o!rwise1 & t any nurse ) common s5se c h no difficulty 9 det]m9+ 9 :at way ! infecti\s mat]ial is elim9at$ f h] pati5ts4 ,:5 ?is fact is kn[n & tak5 into consid]ation x is a comp>atively easy matt] to devise valuable precautions aga9/ di/ribution ( su* mat]ial4 ,x is ?us ( no small importance to rememb] t ! simple pres5ce ( bact]ia 9 food or dr9k is ( no significance unless ^! bact]ia h come f "s s\rce ( disease infection4 ,! ,me?od ( ,di/ribution4--,! bact]ia mu/ next get f ! orig9al s\rce ( ! disease to ! new susceptible individual4 ,bact]ia h no indep5d5t p[]s ( di/ribution unless !y be imm]s$ 9 liquids1 & !re=e _! passage f individual to individual mu/ be a passive "o4 ,!y are readily transf]r$1 h[ev]1 by a numb] ( diff]5t means1 & ! /udy ( ^! means is aid+ mu* 9 *eck+ contagion ,/udy along ?is l9e has %[n t ! means by :i* bact]ia are c>ri$ are sev]al4 ,fir/ we may notice food z a di/ributor4 ,food may become contam9at$ by infecti\s mat]ial 9 _m ways2 = example1 by contact ) sewage1 or ) pollut$ wat]1 or ev5 ) eat+ ut5sils :i* h be5 us$ by pati5ts4 ,wat] is also likely to be contam9at$ ) infecti\s mat]ial1 & is a f]tile s\rce = di/ribut+ typhoid & *ol]a4 ,milk may become contam9at$ 9 a v>iety ( ways1 & be a s\rce ( di/ribut+ ! bact]ia :i* produce typhoid fev]1 tub]culosis1 diph!ria1 sc>let fev]1 & a few o!r less common diseases4 ,aga91 infect$ clo?+1 b$d+1 or eat+ ut5sils may be tak5 f a pati5t & be us$ by ano!r individual )\t prop] cleans+4 ,direct contact1 or contact ) infect$ animals1 furni%es ano!r me?od4 ,insects sometimes c>ry ! bact]ia f p]son to p]son1 & 9 "s diseases 7tub]culosis1 & p]haps sc>let fev] & smallpox7 we mu/ look to ! air z a di/ributor ( ! infecti\s mat]ial4 ,k ( ^! facts is help+ to acc\nt = multitudes ( my/]i\s cases ( infection1 especially :5 we comb9e !m ) ! kn[n s\rces ( contagi\s matt]4 ,means ( ,invasion4--,bact]iology has %[n u t diff]5t species ( p>asitic bact]ia h diff]5t means ( ent]+ ! body1 & t ea* mu/ ent] ! prop] place 9 ord] to get a foo?old4 ,aft] we le>n t typhoid infecti\s mat]ial mu/ ent] ! m\? 9 ord] to produce ! disease2 t tub]culosis may f9d entrance ?r\gh ! nose 9 brea?+1 :ile types ( blood poison+ ent] only ?r\gh w\nds or brok5 sk91 we le>n at once fundam5tal facts z to ! prop] me?ods ( meet+ ^! dang]s4 ,we le>n t ) "s diseases c>e ex]cis$ to prev5t ! swall[+ ( infecti\s mat]ial is suffici5t to prev5t contagion1 :ile ) o!rs ?is is entirely insuffici5t4 ,:5 all ^! facts are und]/ood x is almo/ always p]fectly possible to avoid contagion2 & z ^! facts become m & m widely kn[n direct contagion is sure to become less frequ5t4 ,above all1 x is tell+ u :at becomes ( ! pa?og5ic bact]ia aft] be+ elim9at$ f ! body ( ! pati5t2 h[ !y may exi/ = a long "t /ill active2 h[ !y may lurk 9 fil? or wat] dormant b alive1 or h[ !y may ev5 multiply !re4 ,prev5tive m$ic9e is tell+ u h[ to de/roy ^? ?us ly+ 9 wait = a *ance ( infection1 by discov]+ dis9fectants & tell+ u especially :]e & :5 to use !m4 ,x has already taught u h[ to cru% out c]ta9 =ms ( epidemics by ! prop] means ( de/roy+ bact]ia1 & is less5+ ! dang]s f contagi\s diseases4 ,9 %ort1 ! /udy ( bact]iology has br\ght u into a condition :]e we are no long] helpless 9 ! pres5ce ( a rag+ epidemic4 ,we no long] sit 9 helpless dismay1 z did our ance/ors1 :5 an epidemic ent]s a community1 b1 kn[+ _! causes & s\rces1 set ab\t at once to remove !m4 ,z a result1 sev]e epidemics are becom+ comp>atively %ort-liv$4 ,,bact]ia ,,9 ,,surg]y4 ,9 no l9e ( prev5tive m$ic9e has bact]iology be5 ( s mu* value & s /rik+ 9 its results z 9 surg]y4 ,ev] s9ce surg]y has be5 practis$ surgeons h _h two difficulties to cont5d )4 ,! fir/ has be5 ! %ock result+ f ! op]ation4 ,?is is dep5d5t ^u ! ext5t ( ! op]ation1 & mu/ always be a "p ( a surgical op]ation4 ,! second has be5 second>y effects foll[+ ! op]ation4 ,aft] ! op]ation1 ev5 ?\gh x 0 successful1 !re 7 almo/ sure to arise second>y complications kn[n z surgical fev]1 inflammation1 blood poison+1 gangr5e1 etc41 :i* frequ5tly result$ fatally4 ,^! second>y complications 7 commonly mu* m s]i\s ?an ! %ock ( ! op]ation1 & x us$ to be ! common occurr5ce = ! pati5t to recov] entirely f ! %ock1 b yield to ! fev]s :i* foll[$4 ,!y appe>$ to be entirely unavoidable1 & 7 inde$ reg>d$ z necess>y p>ts ( ! heal+ ( ! w\nd4 ,too frequ5tly x appe>$ t ! great] ! c>e tak5 ) ! pati5t ! m likely he 0 to suff] f "s ( ^! tr\bles4 ,! soldi] :o 0 treat$ on ! battlefield & nurs$ 9 an improvis$ field hospital w\ld frequ5tly recov]1 :ile ! soldi] :o _h ! =tune to be tak5 into ! regul> hospital1 :]e great] c>e 0 possible1 succumb$ to hospital gangr5e4 ,all ^! facts 7 cle>ly recognis$1 b ! surgeon1 ?r\gh ignorance ( _! cause1 0 helpless 9 ! pres5ce ( ^! inflammatory tr\bles1 & felt x always necess>y to take !m into consid]ation4 ,! demon/ration t putrefaction & decay 7 caus$ by bact]ia1 & ! e>ly pro( t ! silkworm disease 0 produc$ by a micro-organism1 l$ to ! sugge/ion t ! inflammatory diseases accompany+ w\nds 7 simil>ly caus$4 ,!re are _m /rik+ simil>ities betwe5 ^! tr\bles & putrefaction1 & ! sugge/ion 0 an obvi\s "o4 ,at fir/1 h[ev]1 & = q a numb] ( ye>s1 x 0 impossible to demon/rate ! !ory by f9d+ ! di/9ct species ( micro- organisms :i* produc$ ! tr\bles4 ,we h already se5 t !re are sev]al diff]5t species ( bact]ia :i* are associat$ ) ?is g5]al class ( diseases1 b t no specific "o has any p>ticul> relation to a def9ite type ( inflammation4 ,?is fact made discov]ies 9 ?is connection a sl[ matt] f ! microscopical /&po9t4 ,b long be=e ?is demon/ration 0 f9ally rea*$ ! !ory _h receiv$ practical application 9 ! =m ( :at has develop$ into antiseptic or aseptic surg]y4 ,antiseptic surg]y is bas$ simply ^u ! attempt to prev5t ! entrance ( bact]ia into ! surgical w\nd4 ,x is assum$ t if ^! organisms are kept f ! w\nd ! heal+ w take place )\t ! second>y fev]s & inflammations :i* occur if !y d get a *ance to gr[ 9 ! w\nd4 ,! !ory met ) decid$ opposition at fir/1 b accumulat+ facts demon/rat$ its value1 & to-day its me?ods h be5 adopt$ ev]y:]e 9 ! civiliz$ _w4 ,z ! evid5ce has be5 accumulat+1 surgeons h le>n$ _m important facts1 =emo/ among :i* is a k ( ! common s\rces f :i* ! infection ( w\nds occurs4 ,at fir/ x 0 ?\ght t ! air 0 ! great s\rce ( infection1 b ! air bact]ia h be5 f\nd to be usually h>mless4 ,x has appe>$ t ! m common s\rces are ! surgeon's in/rum5ts1 or 8 h&s1 or ! clo?+ or sponges :i* are all[$ to come 9 contact ) ! w\nds4 ,x has also appe>$ t ! bact]ia :i* produce ?is class ( tr\bles are common species1 exi/+ ev]y:]e & univ]sally pres5t ar\nd ! body1 cl++ to ! clo?+ or sk91 & always on h& to ent] ! w\nd if occasion (f]s4 ,!y are always pres5t1 b commonly h>mless4 ,!y are n =eign invad]s l ! m viol5t pa?og5ic species1 su* z ^? ( ,asiatic *ol]a1 b may be comp>$ to dome/ic enemies at h&4 ,x is ^! ev]-pres5t bact]ia :i* ! surgeon mu/ gu>d aga9/4 ,! me?ods by :i* he does ?is ne$ n deta9 u "h4 ,!y consi/ ess5tially 9 bact]iological cleanl9ess4 ,! op]ation is p]=m$ ) /]iliz$ in/rum5ts "u mo/ exact+ conditions ( cleanl9ess4 ,! result has be5 a complete revolution 9 surg]y4 ,z ! me?ods h become bett] und]/ood & m ?or\ghly adopt$1 ! in/ances ( second>y tr\bles foll[+ surgical w\nds h become less & less frequ5t until !y h practically disappe>$ 9 all simple cases4 ,to-day ! surgeon recognises t :5 inflammatory tr\bles ( ?is sort foll[ simple surgical w\nds x is a te/imony to 8 c>elessness4 ,! skilful surgeon has le>n$ t ) ! precautions :i* he is able to take to-day he has to fe> only ! direct effect ( ! %ock ( ! w\nd & its subsequ5t direct influ5ce2 b second>y surgical fev]s1 blood poison+1 & surgical gangr5e ne$ n be tak5 into consid]ation at all4 ,inde$1 ! mod]n surgeon h>dly kn[s :at surgical gangr5e is1 & bact]iologi/s h _h practically no *ance to /udy x4 ,second>y infections h l>gely disappe>$1 & ! surgeon is conc]n$ simply ) ! effect ( ! w\nd itself1 & ! p[] ( ! body to )/& ! %ock & subsequ5tly heal ! w\nd4 ,) ^! second>y tr\bles no long] to di/urb him1 ! surgeon has become m & m bold4 ,op]ations =m]ly n dream$ ( are n[ p]=m$ )\t hesitation4 ,9 =m] ye>s an op]ation :i* op5$ ! abdom9al cavity 0 n ?\ght possible1 or at lea/ x 0 s ne>ly c]ta9 to result fatally t x 0 resort$ to only on ! la/ extremity2 :ile to-day su* op]ations are h>dly reg>d$ z s]i\s4 ,ev5 bra9 surg]y is becom+ m & m common4 ,possibly our surgeons are pass+ too f> to ! o!r extreme1 &1 feel+ _! p[] ( p]=m+ s _m op]ations )\t inconv5i5ce or dang]1 !y are us+ ! knife 9 cases :]e x w\ld be bett] to leave ,nature to h]self = h] own heal+4 ,b1 be ?is z x may1 x is impossible to e/imate ! am\nt ( suff]+ prev5t$ & ! numb] ( lives sav$ by ! ma/]y ( ! second>y inflammatory tr\bles :i* us$ to foll[ surgical w\nds4 ,prev5tive m$ic9e1 !n1 has = its object ! prev5tion r ?an ! cure ( disease4 ,by %[+ ! causes ( disease & tell+ u :]e & h[ !y are contract$1 x is tell+ u h[ !y may to a l>ge ext5t be avoid$4 ,unlike practical m$ic9e1 ?is subject is "o :i* has a direct relation to ! g5]al public4 ,:ile x may be be/ t ! k ( curative me?ods be conf9$ l>gely to ! m$ical pr(ession1 x is em95tly desirable t a k ( all ! facts be>+ ^u prev5tive m$ic9e %\ld be di/ribut$ z widely z possible4 ,"o p]son c n satisfactorily apply 8 k ( prev5tive m$ic9e1 if 8 neighb\r is ignorant ( or c>eless ( ! facts4 ,we c n hope to a*ieve ! possibilities ly+ along ?is l9e until !re is a v wide di/ribution ( k4 ,e epidemic t sweeps ?r\gh our communities is a te/imony to ! cry+ ne$ ( education 9 reg>d to su* simple facts z ! s\rce ( infecti\s mat]ial1 ! me?ods ( its di/ribution1 & ! means ( r5d]+ x h>mless4 ,,prev5tion ,,9 ,,inoculation4 ,x has long be5 recognis$ t 9 mo/ cases recov]y f "o attack ( a contagi\s disease r5d]s an individual m or less immune aga9/ a second attack4 ,x is unusual = an individual to h ! same contagi\s disease twice4 ,?is belief is c]ta9ly bas$ ^u fact1 al?\gh ! immunity ?us acquir$ is subject to wide v>iations4 ,!re are "s diseases 9 :i* !re is little reason = ?9k+ t any immunity is acquir$1 z 9 ! case ( tub]culosis1 :ile !re are o!rs 9 :i* ! immunity is v great & v la/+1 z 9 ! case ( sc>let fev]4 ,moreov]1 ! immunity diff]s ) individuals4 ,:ile "s p]sons appe> to acquire a la/+ immunity by recov]y f a s+le attack1 o!rs w yield to a second attack v readily4 ,b 9 spite ( ?is ! fact ( su* acquir$ immunity is beyond "q4 ,app>5tly all infecti\s diseases f :i* a real recov]y takes place are foll[$ by a c]ta9 am\nt ( protection f a second attack2 b ) "s diseases ! immunity is v fleet+1 :ile ) o!rs x is m la/+4 ,diseases :i* produce a g5]al infection ( ! :ole sy/em are1 z a rule1 m likely to give rise to a la/+ immunity ?an ^? :i* affect only small p>ts4 ,tub]culosis1 :i*1 z already notic$1 is commonly q localiz$ 9 ! body1 has little p[] ( convey+ immunity1 :ile a disease l sc>let fev]1 :i* affects ! :ole sy/em1 conveys a m la/+ protection4 ,su* immunity has long be5 kn[n1 & 9 ! e>li] ye>s 0 sometimes volunt>ily acquir$2 ev5 to-day we f9d "s individuals mak+ use ( ! pr9ciple4 ,x appe>s t a mild attack ( su* diseases produces immunity equally well ) a sev]e attack1 & act+ ^u ?is fact mo!rs h n infrequ5tly int5tionally expos$ _! *ildr5 to c]ta9 diseases at seasons :5 !y are mild1 9 ord] to h ! disease ov] ) & _! *ildr5 protect$ 9 ! future4 ,ev5 ! m sev]e diseases h at times be5 ?us volunt>ily acquir$4 ,9 ,*9a x has sometimes be5 ! cu/om ?us to acquire smallpox4 ,su* me?ods are decid$ly h]oic1 & ( c\rse to be he>tily condemn$4 ,b ! pr9ciple t a mild type ( ! disease conveys protection has be5 made use ( 9 a m logical & def5sible way4 ,! fir/ in/ance ( ?is pr9ciple 0 9 vacc9ation aga9/ smallpox1 n[ practis$ = m ?an a c5tury4 ,c[pox is d\btless closely relat$ to smallpox1 & an attack ( ! =m] conveys a c]ta9 am\nt ( protection aga9/ ! latt]4 ,x 0 easy1 !re=e1 to inoculate man ) "s ( ! infecti\s mat]ial f c[pox1 & ?us give him "s protection aga9/ ! m s]i\s smallpox4 ,?is 0 a purely empirical discov]y1 & vacc9ation 0 practis$ long be=e ! pr9ciple und]ly+ x 0 und]/ood1 & long be=e ! g]m nature ( disease 0 recognis$4 ,! pr9ciple 0 reviv$ aga91 h[ev]1 by ,pa/eur1 & ?is "t ) a logical ?\ght z to its value4 ,:ile work+ ^u an?rax among animals1 he le>n$ t "h1 z 9 o!r diseases1 recov]y1 :5 x occurr$1 convey$ immunity4 ,?is l$ him to ask if x 7 n possible to devise a me?od ( giv+ to animals a mild =m ( ! disease & ?us protect !m f ! m sev]e type4 ,! problem ( giv+ a mild type ( ?is extraord9>ily sev]e disease 0 n an easy "o4 ,x c\ld n be done1 ( c\rse1 by inoculat+ ! animals ) a small numb] ( ! bact]ia1 = _! p[] ( multiplication w\ld soon make !m indef9itely num]\s4 ,x 0 necess>y 9 "s way to dim9i% _! viol5ce4 ,pa/eur succe$$ 9 do+ ?is by caus+ !m to gr[ 9 culture fluids = a "t at a high temp]ature4 ,?is treatm5t dim9i%$ _! viol5ce s mu* t !y c\ld be inoculat$ into cattle1 :]e !y produc$ only ! milde/ type ( indisposition1 f :i* ! animals spe$ily recov]$4 ,b ev5 ?is mild type ( ! disease 0 triumphantly demon/rat$ to protect ! animals f ! mo/ sev]e =m ( an?rax4 ,! discov]y 0 naturally hail$ z a mo/ rem>kable "o1 & "o :i* promis$ great ?+s 9 ! future4 ,if x 0 ?us possible1 by direct laboratory me?ods1 to f9d a means ( inoculat+ aga9/ a s]i\s disease l an?rax1 :y c\ld n ! same pr9ciple be appli$ to human diseases8 ,! en?usia/s began at once to look =w>d to a "t :5 all diseases %\ld be ?us conqu]$4 ,b ! pr9ciple has n borne ! fruit at fir/ expect$4 ,!re is little d\bt t x might be appli$ to q a numb] ( human diseases if a s]i\s attempt %\ld be made4 ,b sev]al objections arise aga9/ its wide application4 ,9 ! fir/ place1 ! inoculation ?us necess>y is really a s]i\s matt]4 ,ev5 vacc9ation1 z is well kn[n1 sometimes1 ?r\gh faulty me?ods1 results fatally1 & x is a v s]i\s ?+ to exp]im5t ^u human be+s ) any?+ s p[]ful = ill z pa?og5ic bact]ia4 ,! s]i\sness ( ! disease smallpox1 its extraord9>y contagi\sness1 & ! comp>atively mild results ( vacc9ation1 h made u will+ to und]go vacc9ation at times ( epidemics to avoid ! some:at great probability ( tak+ ! disease4 ,b mank9d is unwill+ to und]go su* an op]ation1 ev5 ?\gh mild1 = ! purpose ( avoid+ o!r less sev]e diseases1 or diseases :i* are less likely to be tak54 ,we are unwill+ to be inoculat$ aga9/ mild diseases1 or aga9/ ! m sev]e ones :i* are uncommon4 ,= in/ance1 a me?od has be5 devis$ = r5d]+ animals immune aga9/ lockjaw1 :i* w\ld probably apply equally well to man4 ,b mank9d 9 g5]al w nev] adopt x1 s9ce ! dang] f lockjaw is s small4 ,inoculation mu/ !n be res]v$ = diseases :i* are s sev]e & s common1 or :i* occur 9 p]iodical epidemics ( s great sev]ity1 z to make p 9 g5]al will+ to submit to inoculation z a protection4 ,a fur!r objection arises f ! fact t ! immunity acquir$ is n necess>ily la/+4 ,! cattle inoculat$ aga9/ an?rax reta9 _! protective p[]s = only a few mon?s4 ,h[ long simil> immunity might be reta9$ 9 o!r cases we c n say1 b pla9ly ?is fact w\ld effectually prev5t ?is me?od ( protect+ mank9d f be+ us$ except 9 special cases4 ,x is out ( ! "q to ?9k ( con/ant & repeat$ inoculations aga9/ v>i\s diseases4 ,z a result1 ! pr9ciple ( inoculation z an aid 9 prev5tive m$ic9e has n prov$ ( v mu* value4 ,! only o!r human disease 9 :i* x has be5 attempt$ s]i\sly is ,asiatic *ol]a4 ,?is disease 9 times ( epidemics is s sev]e & ! *ance ( infection is s great z to ju/ify su* inoculation4 ,sev]al bact]iologi/s h 9 ! la/ few ye>s be5 try+ to discov] a h>mless me?od ( inoculat+ aga9/ ?is disease4 ,app>5tly !y h succe$$1 = exp]im5ts 9 ,india1 ! home ( ! *ol]a1 h be5 z successful z c\ld be anticipat$4 ,bact]iological sci5ce has n[ 9 its possession a means ( inoculation aga9/ *ol]a :i* is p]haps z efficaci\s z vacc9ation is aga9/ smallpox4 ,:e!r x w ev] be us$ to any ext5t is d\btful1 s9ce1 z already po9t$ out1 we are 9 a position to avoid *ol]a epidemics by o!r means4 ,if we c protect our communities by gu>d+ ! wat] supply1 x is n likely t ! me?od ( inoculation w ev] be widely us$4 ,ano!r in/ance ( ! application ( prev5tive inoculation has be5 made1 b "o bas$ ^u a diff]5t pr9ciple4 ,hydrophobia is c]ta9ly "o ( ! mo/ horrible ( diseases1 al?\gh comp>atively r>e4 ,its r>ity w\ld effectually prev5t mank9d f submitt+ to a g5]al inoculation aga9/ x1 b its sev]ity w\ld make "o :o _h be5 expos$ to x by ! bite ( a rabid animal ready to submit to almo/ any treatm5t t promis$ to w>d (f ! disease4 ,9 ! attempt to discov] a means ( inoculat+ aga9/ ?is disease x 0 necess>y1 !re=e1 to f9d a me?od t c\ld be appli$ aft] ! "t ( exposure--i4e41 aft] ! individual _h be5 bitt5 by ! rabid animal4 ,=tunately1 ! disease has a long p]iod ( incubation1 & "o t has prov$ long en\gh = ! purpose4 ,a me?od ( inoculation aga9/ ?is disease has be5 devis$ by ,pa/eur1 :i* c be appli$ aft] ! individual has be5 bitt5 by ! rabid animal4 ,app>5tly1 h[ev]1 ?is prev5tive inoculation is dep5d5t ^u a diff]5t pr9ciple f vacc9ation or inoculation aga9/ an?rax4 ,x does n appe> to give rise to a mild =m ( ! disease1 ?us protect+ ! individual1 b r to an acquir$ tol]ance ( ! *emical poisons produc$ by ! disease4 ,x is a well-kn[n physiological fact t ! body c become accu/om$ to tol]ate poisons if inur$ to !m by successively l>g] & l>g] doses4 ,x is by ?is p[]1 app>5tly1 t ! inoculation aga9/ hydrophobia produces its effect4 ,mat]ial conta9+ ! hydrophobia poison 7tak5 f ! sp9al cord ( a rabbit dead ) ! disease7 is inject$ into ! individual aft] he has be5 bitt5 by a rabid animal4 ,! poison\s mat]ial 9 ! fir/ injection is v weak1 b is foll[$ lat] by a m p[]ful inoculation4 ,! result is t aft] a %ort "t ! individual has acquir$ ! p[] ( resi/+ ! hydrophobia poisons4 ,be=e ! incubation p]iod ( ! orig9al infecti\s matt] f ! bite ( ! rabid animal has pass$1 ! inoculat$ individual has s ?or\ghly acquir$ a tol]ance ( ! poison t he successfully resi/s ! attack ( ! infection4 ,?is me?od ( inoculation ?us neutralizes ! effects ( ! disease by anticipat+ !m4 ,! me?od ( treatm5t ( hydrophobia met ) extraord9>ily viol5t opposition4 ,= sev]al ye>s x 0 reg>d$ z a mi/ake4 ,b ! con/antly accumulat+ /ati/ics f ! ,pa/eur ,in/itute h be5 s ov]:elm+ly on "o side z to quiet opposition & br+ ab\t a g5]al conviction t ! me?od is a success4 ,! me?od ( prev5tive inoculation has n be5 ext5sively appli$ to human diseases 9 addition to ^? m5tion$4 ,9 a few cases a simil> me?od has be5 us$ to gu>d aga9/ diph!ria4 ,among animals1 exp]im5t has %[n t su* me?ods c q easily be obta9$1 & d\btless ! same w\ld be true ( mank9d if x 0 ?\ght practical or feasible to apply !m4 ,b1 = reasons m5tion$1 ?is feature ( prev5tive m$ic9e w always rema9 r unimportant1 & w be conf9$ to a few ( ! m viol5t diseases4 ,x may be well to raise ! "q z to :y a s+le attack ) recov]y conveys immunity4 ,?is "q is really a "p ( ! "o already discuss$ z to ! me?od by :i* ! body cures disease4 ,we h se5 t ?is is 9 "p due to ! developm5t ( *emical sub/ances :i* ei!r neutralize ! poisons or act z g]micide ^u ! bact]ia1 or bo?1 & p]haps due 9 "p to an active de/ruction ( bact]ia by cellul> activity 7phagocytosis74 ,!re is little reason to d\bt t x is ! same set ( activities :i* r5d]s ! animal immune4 ,! =ces :i* drive (f ! invad+ bact]ia 9 "o case are /ill pres5t to prev5t a second attack ( ! same species ( bact]ium4 ,! l5g? ( "t dur+ :i* ^! =ces are active & suffici5t to cope ) any new invad]s det]m9es ! l5g? ( "t dur+ :i* ! immunity la/s4 ,until1 !re=e1 we c answ] ) m exactness j h[ cure is br\ght ab\t 9 case ( disease1 we %all be unable to expla9 ! me?od ( immunity4 ,,limits ,,( ,,prev5tive ,,m$ic9e4 ,) all ! advance 9 prev5tive m$ic9e we c n hope to avoid disease entirely4 ,we are discov]+ t ! s\rces ( disease are on all sides ( u1 & s omnipres5t t to avoid !m completely is impossible4 ,if we 7 to apply to our lives all ! safegu>ds :i* bact]iology has taught u %\ld be appli$ 9 ord] to avoid ! diff]5t diseases1 we w\ld surr\nd ourselves ) conditions :i* w\ld make life intol]able4 ,x w\ld be oppressive en\gh = u to eat no food except :5 x is hot1 to dr9k no wat] except :5 boil$1 & to dr9k no milk except aft] /]ilization2 b ^! w\ld n satisfy ! necess>y conditions = avoid+ disease4 ,to meet all dang]s1 we %\ld h&le no?+ :i* has n be5 /]iliz$1 or %\ld foll[ ! h&l+ by imm$iately /]iliz+ ! h&s2 we %\ld we> only dis9fect$ clo!s1 we %\ld nev] put our f+]s 9 our m\?s or t\* our food ) !m2 we %\ld cease to ride 9 public conveyances1 &1 inde$1 %\ld cease to brea! common air4 ,absolute prev5tion ( ! *ance ( infection is impossible4 ,! mo/ t prev5tive m$ic9e c hope = is to po9t out ! mo/ common & prolific s\rces ( infection1 & ?us enable civiliz$ man to avoid "s ( 8 mo/ common tr\bles4 ,x becomes a "q1 !re=e1 :]e we w be/ draw ! l9e 9 ! employm5t ( safegu>ds4 ,%all we dr9k none except /]iliz$ milk1 & no wat] unless boil$8 or %all we put ^! occasional s\rces ( dang] 9 ! same category ) bicycle & railroad accid5ts1 dang]s :i* c be avoid$ by n us+ ! bicycle or rid+ on ! rail1 b 9 reg>d to :i* ! rem$y is too oppressive = application8 ,inde$1 :5 view$ 9 a broad philosophical light x may n be ! be/ c\rse = mank9d to %un all dang]s4 ,/r5g? 9 ! organism comes f ! use r ?an ! disuse ( our p[]s4 ,x is c]ta9 t ! g5]al heal? & vig\r ( mank9d is to be develop$ by meet+ r ?an by %unn+ dang]s4 ,resi/ance to disease means bodily vig\r1 & ?is is to be develop$ 9 mank9d by ! application ( ! pr9ciple ( natural selection4 ,9 accordance ) ?is pr9ciple1 disease w gradually remove ! individuals ( weak resi/+ p[]s1 leav+ ^? ( great] vig\r4 ,p>asitic bact]ia are ?us a means ( prev5t+ ! cont9u$ life ( ! weak] memb]s ( ! community1 & s t5d to /r5g!n mank9d4 ,by prev5tive m$ic9e _m a weak individual :o w\ld o!rwise succumb e>li] 9 ! /ruggle is enabl$ to live a few ye>s long]4 ,:atev] be our humanit>ian feel+ = ! individual1 we c n fail to admit t ?is survival ( ! weak is ( no b5efit to ! race s f> z ! developm5t ( physical nature is conc]n$4 ,inde$1 if we 7 to take into consid]ation simply ! physical nature ( man we %\ld be oblig$ to recomm5d a sy/em su* z ! anci5t ,sp>tans develop$1 ( expos+ to dea? all weakly individuals1 t only ! /rong might live to become ! fa!rs ( future g5]ations4 ,9 ?is light1 ( c\rse1 p>asitic diseases w\ld be an assi/ance r ?an a detrim5t to ! human race4 ,( c\rse su* pr9ciples w nev] aga9 be dom9ant among m51 & our consci5ce tells u to d all we c to help ! weak4 ,we %all d\btless d all possible to develop prev5tive m$ic9e 9 ord] to gu>d ! weak aga9/ p>asitic organisms4 ,b x is at all ev5ts well = u to rememb] t we c nev] hope to develop ! /r5g? ( ! human race by %unn+ evil1 b r by combat+ x1 & ! p[] ( ! human race to resi/ ! invasions ( ^! organisms w nev] be develop$ by ! l9e ( action :i* gu>ds u f attack4 ,"h1 z 9 o!r directions1 ! pr9ciples ( mod]n humanity h1 toge!r ) _! und\bt$ fav\rable influ5ce ^u mank9d1 c]ta9 t5d5cies t[>d weakness4 ,:ile we %all /ill d our utmo/ to develop prev5tive m$ic9e 9 a prop] way1 x may be well = u to rememb] ^! facts :5 we come to ! practical "q ( det]m9+ :]e to draw ! limits ( ! application ( me?ods = prev5t+ infecti\s diseases4 ,,curative ,,m$ic9e4 ,bact]iology has hi!rto contribut$ less to curative ?an to prev5tive m$ic9e4 ,nev]!less1 its contributions to curative m$ic9e h n be5 unimportant1 & !re is promise ( mu* m 9 ! future4 ,x is1 ( c\rse1 unsafe to make pr$ictions = ! future1 b ! accompli%m5ts ( ! la/ few ye>s give mu* hope z to fur!r results4 ,,drugs4 ,x 0 at fir/ ?\ght t a k ( ! specific bact]ia :i* cause a disease w\ld give a ready means ( f9d+ specific drugs = ! cure ( su* disease4 ,if a def9ite species ( bact]ium causes a disease & we c cultivate ! organism 9 ! laboratory1 x is easy to f9d "s drugs :i* w be fatal to its gr[?1 & ^! same drugs1 x w\ld seem1 %\ld be valuable z m$ic9es 9 ^! diseases4 ,?is hope has1 h[ev]1 prov$ l>gely illusive4 ,x is v easy to f9d "s drug :i* proves fatal to ! specific g]ms :ile gr[+ 9 ! culture m$ia ( ! laboratory1 b commonly ^! are ( little or no use :5 appli$ z m$ic9es4 ,9 ! fir/ place1 su* sub/ances are usually v deadly poisons4 ,corrosive sublimate is a sub/ance :i* de/roys all pa?og5ic g]ms ) great rapidity1 b x is a deadly poison1 & c n be us$ z a drug 9 suffici5t quantity to de/roy ! p>asitic bact]ia 9 ! body )\t at ! same "t produc+ poison\s effects on ! body itself4 ,x is evid5t t = any drug to be ( value 9 ?us de/roy+ bact]ia x mu/ h "s specially /rong action ^u ! bact]ia4 ,its g]micide action on ! bact]ia %\ld be s /rong t a dose :i* w\ld be fatal or v injuri\s to !m w\ld be too small to h a delet]i\s influ5ce on ! body ( ! individual4 ,x has n prov$ an easy task to discov] drugs :i* w h any value z g]micides :5 us$ 9 quantities s small z to produce no injuri\s effect on ! body4 ,a second difficulty is 9 gett+ ! drug to produce its effect at ! "r po9t4 ,a few diseases1 z we h notic$1 are produc$ by bact]ia :i* di/ribute !mselves almo/ indiscrim9ately ov] ! body2 b ! majority are some:at def9itely localiz$ 9 special po9ts4 ,tub]culosis may attack a s+le gl& or a s+le lobe ( ! lung4 ,typhoid g]m is localiz$ 9 ! inte/9es1 liv]1 sple51 etc4 ,ev5 if x 7 possible to f9d "s drug :i* w\ld h a v specific effect ^u ! tub]culosis bacillus1 x is pla9 t x w\ld be a v que/ionable me?od ( proc$ure to introduce ?is into ! :ole sy/em simply t x might h an effect ^u a v small isolat$ gl&4 ,sometimes su* a bact]ial affection may be localiz$ 9 places :]e x c be specially treat$1 z 9 ! case ( an attack on a d]mal gl&1 & 9 ^! cases "s ( ! g]micides h prov$ to be ( mu* value4 ,inde$1 ! use ( v>i\s dis9fectants connect$ ) abscesses & sup]ficial infections has prov$ ( mu* value4 ,to ?is ext5t1 9 dis9fect+ w\nds & z a local application1 ! developm5t ( our k ( dis9fectants has giv5 no little aid to curative m$ic9e4 ,v little success1 h[ev]1 has result$ 9 ! attempt to f9d specific drugs = specific diseases1 & x is at lea/ d\btful :e!r _m su* w ev] be f\nd4 ,! ne>e/ approa* to x is qu99e z a specific poison = mal>ial tr\bles4 ,mal>i\s diseases are n1 h[ev]1 produc$ by bact]ia b by a microscopic organism ( a v diff]5t nature1 ?\ght to be an animal r ?an a plant4 ,besides ?is !re has be5 little or no success 9 discov]+ specifics 9 ! =m ( drugs :i* c be giv5 z m$ic9es or inoculat$ ) ! hope ( de/roy+ special k9ds ( pa?og5ic bact]ia )\t injury to ! body4 ,:ile x is unwise to make pr$ictions z to future discov]ies1 !re seems at pres5t little hope = a developm5t ( curative m$ic9e along ^! l9es4 ,,vis ,,m$icatrix ,,naturae4 ,! /udy ( bact]ial diseases z !y progress 9 ! body has emphasiz$ above all ?+s ! fact t diseases are ev5tually cur$ by a natural r ?an by an artificial process4 ,if a pa?og5ic bact]ium succe$s 9 pass+ ! out] safegu>ds & ent]+ ! body1 & if x !n succe$s 9 ov]com+ ! =ces ( resi/ance :i* we h already notic$1 x w beg9 to multiply & produce mis*ief4 ,?is multiplication n[ goes on = a "t un*eck$1 & !re is little reason to expect t we c ev] d mu* t[>d *eck+ x by means ( drugs4 ,b aft] a little1 conditions arise :i* are ho/ile to ! fur!r gr[? ( ! p>asite4 ,^! ho/ile conditions are produc$ p]haps 9 "p by ! secretions f ! bact]ia1 = bact]ia are unable to fl\ri% 9 a m$ium conta9+ mu* ( _! own secretions4 ,! secretions :i* !y produce are poisons to !m z well z to ! individual 9 :i* !y gr[1 & aft] ^! h become q abundant ! fur!r gr[? ( ! bact]ium is *eck$ & f9ally /opp$4 ,p>tly1 also1 mu/ we conclude t ^! ho/ile conditions are produc$ by active vital p[]s 9 ! body ( ! individual attack$4 ,! individual1 z we h se51 9 "s cases develops a quantity ( "s sub/ance :i* neutralizes ! bact]ial poisons & ?us prev5ts _! hav+ _! maximum effect4 ,?us reliev$ f ! direct effects ( ! poisons1 ! resi/+ p[]s are recup]at$ & once m beg9 to produce a direct de/ruction ( ! bact]ia4 ,possibly ! bact]ia1 be+ n[ weak5$ by ! pres5ce ( _! own products ( gr[?1 m readily yield to ! resi/+ =ces ( ! cell life ( ! body4 ,possibly ! resi/+ =ces are decid$ly increas$ by ! reactive effect ( ! bact]ia & _! poisons4 ,b1 at all ev5ts1 9 cases :]e recov]y f p>asitic diseases occurs1 ! reviv$ p[]s ( resi/ance f9ally ov]come ! bact]ia1 de/roy !m or drive !m (f1 & ! body recov]s4 ,all ?is is1 ( c\rse1 a natural process4 ,! recov]y f a disease produc$ by ! invasion ( p>asitic bact]ia dep5ds ^u :e!r ! body c resi/ ! bact]ial poisons long en\gh = ! recup]ation ( its resi/+ p[]s4 ,if ^! poisons are v viol5t & produc$ rapidly1 dea? w probably occur be=e ! resi/+ p[]s are /rong en\gh to drive (f ! bact]ia4 ,9 ! case ( "s diseases ! poisons are s viol5t t ?is practically always occurs1 recov]y be+ v exceptional4 ,! poison produc$ by ! tetanus bacillus is ( ?is nature1 & recov]y f lockjaw is ( ! r>e/ occurr5ce4 ,b 9 _m o!r diseases ! body is able to )/& ! poison1 & lat] to recov] its resi/+ p[]s suffici5tly to drive (f ! invad]s4 ,9 all cases1 h[ev]1 ! process is a natural "o & dep5d5t ^u ! vital activity ( ! body4 ,x is bas$ at ! f\ndation1 d\btless1 ^u ! p[]s ( ! body cells1 ei!r ! phagocytes or o!r active cells4 ,! body has1 9 %ort1 its own =ces = repell+ invasions1 & ^u ^! =ces mu/ we dep5d = ! p[] to produce recov]y4 ,x is evid5t t all ^! facts give u v little enc\ragem5t t we %all ev] be able to cure diseases directly by means ( drugs to de/roy bact]ia1 b1 on ! contr>y1 t we mu/ ev] dep5d ^u ! resi/+ p[]s ( ! body4 ,!y tea* u1 moreov]1 along :at l9e we mu/ look = ! future developm5t ( curative m$ic9e4 ,x is evid5t t sci5tific m$ic9e mu/ turn its att5tion t[>d ! /r5g!n+ & /imulat+ ( ! resi/+ & curative =ces ( ! body4 ,x mu/ be ! physician's aim to enable ! body to resi/ ! poisons z well z possible & to /imulate x to re-en=ce its resi/ant =ces4 ,drugs h a place 9 m$ic9e1 ( c\rse1 b ?is place is *iefly to /imulate ! body to react aga9/ its invad+ ho/s4 ,!y are1 z a rule1 n specific aga9/ def9ite diseases4 ,we c n hope = mu* 9 ! way ( discov]+ special m$ic9es adapt$ to special diseases4 ,we mu/ simply look ^u !m z means :i* ! physician has 9 h& = /imulat+ ! natural =ces ( ! body1 & ^! may d\btless v>y ) diff]5t individual natures4 ,recognis+ ?is1 we c see also ! logic ( ! small dose z comp>$ to ! l>ge dose4 ,a small dose ( a drug may s]ve z a /imulant = ! lagg+ =ces1 :ile a l>g] dose w\ld directly repress !m or produce injuri\s second>y effects4 ,z soon z we recognise t ! aim ( m$ic9e is n to de/roy ! disease b r to /imulate ! resi/+ =ces ( ! body1 ! :ole logic ( !rapeutics assumes a new aspect4 ,physicians h und]/ood ?is1 &1 especially 9 rec5t ye>s1 h guid$ _! practice by x4 ,if a mod]ate dose ( qu99e w *eck mal>ia 9 a few days1 x does n foll[ t twice ! dose w d x 9 half ! "t or ) twice ! c]ta9ty4 ,! l>g] doses ( ! pa/1 int5d$ to drive out ! disease1 h be5 ev]y:]e replac$ by small] doses design$ to /imulate ! lagg+ body p[]s4 ,! mod]n physician makes no attempt to cure typhoid fev]1 hav+ long s9ce le>n$ 8 inability to d ?is1 at lea/ if ! fev] once gets a foo?old2 b he turns 8 att5tion to e conceivable means ( increas+ ! body's /r5g? to resi/ ! typhoid poison1 confid5t t if he c ?us enable ! pati5t to resi/ ! poison+ effects ( ! typhotox9e 8 pati5t w 9 ! end react aga9/ ! disease & drive (f ! invad+ bact]ia4 ,! physician's duty is to wat* & gu>d1 b he mu/ dep5d ^u ! vital p[]s ( 8 pati5t to c>ry on alone ! actual battle ) ! bact]ial invad]s4 ,,antitox9es4 ,9 v rec5t times1 h[ev]1 our bact]iologi/s h be5 po9t+ out to ! _w c]ta9 entirely new means ( assi/+ ! body to fight its battles ) bact]ial diseases4 ,z already notic$1 "o ( ! primal =ces 9 ! recov]y1 f "s diseases1 at lea/1 is ! developm5t 9 ! body ( a sub/ance :i* acts z an antidote to ! bact]ial poison4 ,s long z ?is antitox9e is n pres5t ! poisons produc$ by ! disease w h _! full effect to weak5 ! body & prev5t ! revival ( its resi/+ p[]s to drive (f ! bact]ia4 ,pla9ly1 if x is possible to obta9 ?is antitox9e 9 quantity & !n inoculate x into ! body :5 ! toxic poisons are pres5t1 we h a means = decid$ly assi/+ ! body 9 its ef=ts to drive (f ! p>asites4 ,su* an antidote to ! bact]ial poison w\ld n1 inde$1 produce a cure1 b x w\ld p]haps h ! effect ( annull+ ! action ( ! poisons1 & w\ld ?us give ! body a mu* great] *ance to ma/] ! bact]ia4 ,x is ^u ?is pr9ciple t is bas$ ! use ( antitox9es 9 diph!ria & tetanus ,x w be cle> t to obta9 ! antitox9e we mu/ dep5d ^u "s natural me?od = its production4 ,we d n "k en\gh ( ! *emical nature ( ! antitox9es to manufacture !m artificially4 ,( c\rse we c n d5y ! possibility ( _! artificial production1 & c]ta9 v rec5t exp]im5ts indicate t p]haps !y may be made by ! ag5cy ( electricity4 ,at pres5t1 h[ev]1 we mu/ use natural me?ods1 & ! "o commonly adopt$ is simple4 ,"s animal is select$ ^: blood is h>mless to man & t is subject to ! disease to be treat$4 ,= diph!ria a horse is *os54 ,?is animal is inoculat$ ) small quantities ( ! diph!ria poison )\t ! diph!ria bacillus4 ,?is poison is easily obta9$ by caus+ ! diph!ria bacillus to gr[ 9 common m$ia 9 ! laboratory = a :ile1 & ! tox9es develop 9 quantity2 !n1 by prop] filtration1 ! bact]ia !mselves c be remov$1 leav+ a pure solution ( ! toxic poison4 ,small quantities ( ?is poison are inoculat$ into ! horse at successive int]vals4 ,! effect on ! horse is ! same z if ! animal _h ! disease4 ,its cells react & produce a consid]able quantity ( ! antitox9e :i* rema9s 9 solution 9 ! blood ( ! animal4 ,?is is n !ory1 b demon/rat$ fact4 ,! blood ( a horse s treat$ is f\nd to h ! effect ( neutraliz+ ! diph!ria poison1 al?\gh ! blood ( ! horse be=e su* treatm5t has no su* effect4 ,?us !re is develop$ 9 ! horse's blood a quantity ( ! antitox9e1 & n[ x may be us$ by physicians :]e ne$$4 ,if "s ( ?is horse's blood1 prop]ly treat$1 be inoculat$ into ! body ( a p]son :o is suff]+ f diph!ria1 its effect1 provid$ ! !ory ( antitox9es is true1 w be to c\nt]act 9 "p1 at lea/1 ! poisons :i* are be+ produc$ 9 ! pati5t by ! diph!ria bacillus4 ,?is does n cure ! disease nor 9 itself drive (f ! bacilli1 b x does protect ! body f ! poisons to su* an ext5t z to enable x m readily to ass]t its own resi/+ p[]s4 ,?is me?od ( us+ antitox9es z a help 9 cur+ disease is v rec5t1 & we c n ev5 guess :at may come ( x4 ,x has app>5tly be5 successfully appli$ 9 diph!ria4 ,x has also be5 us$ 9 tetanus ) slight success4 ,! same pr9ciple has be5 us$ 9 obta9+ an antidote = ! poison ( snake bites1 s9ce x has appe>$ t 9 ?is k9d ( poison+ ! body w develop an antidote to ! poison if x gets a *ance4 ,horses h be5 treat$ 9 ! same way z ) ! diph!ria poison1 & 9 ! same way !y develop a sub/ance :i* neutralizes ! snake poison4 ,o!r diseases are be+ /udi$ to-day ) ! hope ( simil> results4 ,h[ mu* fur!r ! pr9ciple w g we c n say1 nor c we be v confid5t t ! same pr9ciple w apply v widely4 ,! p>asitic diseases are s diff]5t 9 nature t we c h>dly expect t a me?od :i* is satisfactory 9 meet+ "o ( ! diseases w be v likely to be adapt$ to ano!r4 ,vacc9ation has prov$ ( value 9 smallpox1 b is n ( use 9 o!r human diseases4 ,inoculation ) weak5$ g]ms has prov$ ( value 9 an?rax & f[l *ol]a1 b w n apply to all diseases4 ,ea* ( ^! p>asites mu/ be f\ght by special me?ods1 & we mu/ n expect t a me?od t is ( value 9 "o case mu/ necess>ily be ( use else:]e4 ,above all1 we mu/ rememb] t ! antitox9es d n cure 9 !mselves2 !y only gu>d ! body f ! weak5+ effects ( ! poisons until x c cure itself1 &1 unless ! body has resi/+ p[]s1 ! antitox9e w fail to produce ! desir$ results4 ,"o fur!r po9t 9 ! action ( ! antitox9es mu/ be notic$4 ,z we h se51 a recov]y f an attack ( mo/ g]m diseases r5d]s ! individual = a "t immune aga9/ a second attack4 ,?is applies less1 h[ev]1 to a recov]y aft] ! artificial inoculation ) antitox9e ?an :5 ! individual recov]s )\t su* aid4 ,if ! individual recov]s q indep5d5tly ( ! artificial antitox9e1 he does s 9 "p because he has develop$ ! antitox9es = c\nt]act+ ! poison by 8 own p[]s4 ,8 cellul> activities h1 9 o!r words1 be5 = a mom5t at lea/ turn$ 9 ! direction ( production ( antitox9es4 ,x is to be expect$1 !re=e1 t aft] ! recov]y !y w /ill h ?is p[]1 & s long z !y possess x ! individual w h protection f a second attack4 ,:51 h[ev]1 ! recov]y results f ! artificial inoculation ( antitox9e ! body cells h n actively produc$ antitox9e4 ,! neutralization ( ! poisons has be5 a passive "o1 & aft] recov]y ! body cells are no m engag$ 9 produc+ antitox9e ?an be=e4 ,! antitox9e :i* 0 inoculat$ is soon elim9at$ by secretion1 & ! body is left ) practically ! same liability to attack z be=e4 ,its immunity is decid$ly fleet+1 s9ce x 0 dep5d5t n ^u any activity on ! "p ( ! body1 b ^u an artificial inoculation ( a mat]ial :i* is rapidly elim9at$ by secretion4 ,,conclusion4 ,x is hop$ t ! outl9e :i* has be5 giv5 ( ! bact]ial life ( ,nature may s]ve to give "s adequate idea ( ^! organisms & correct ! errone\s impressions 9 reg>d to !m :i* are widely preval5t4 ,x w be se5 t1 z our fri5ds1 bact]ia play a va/ly m important "p 9 ,nature ?an !y d z our enemies4 ,^! plants are m9ute & extraord9>ily simple1 b1 nev]!less1 !re exi/s a l>ge numb] ( diff]5t species4 ,! numb] ( describ$ =ms already runs f> into ! hundr$s1 & we d n yet appe> to be approa*+ ! end ( !m4 ,!y are ev]y:]e 9 ,nature1 & _! numb]s are va/ beyond conception4 ,_! p[]s ( multiplication are inconceivable1 & _! ability to produce pr(\nd *emical *anges is !re=e unlimit$4 ,?is va/ ho/ ( liv+ be+s ?us con/itutes a =ce or s]ies ( =ces ( trem5d\s significance4 ,mo/ ( ! va/ multitude we mu/ reg>d z our fri5ds4 ,^u !m ! f>m] is dep5d5t = ! f]tility ( 8 soil & ! possibility ( cont9u$ life 9 8 crops4 ,^u !m ! dairyman is dep5d5t = 8 flav\rs4 ,^u !m important f]m5tative indu/ries are dep5d5t1 & _! univ]sal p[]s come into action ^u a comm]cial scale 9 _m a place :]e we h little ?\ght ( !m 9 pa/ ye>s4 ,we mu/ look ^u !m z ag5ts ev] at "w1 by means ( :i* ! surface ( ,nature is enabl$ to rema9 fre% & gre54 ,_! p[] is fundam5tal1 & _! activities are necess>y = ! cont9uance ( life4 ,a small numb] ( ! va/ ho/1 a score or two ( species1 un=tunately = u1 f9d _! mo/ fav\rable liv+ place 9 ! human body1 & ?us become human p>asites4 ,by _! gr[? !y develop poisons & produce disease4 ,?is small class ( p>asites are !n decid$ly our enemies4 ,b1 tak5 all toge!r1 we mu/ reg>d ! bact]ia z fri5ds & allies4 ,)\t !m we %\ld n h our epidemics1 b )\t !m we %\ld n exi/4 ,)\t !m x might be t "s individuals w\ld live a little long]1 if inde$ we c\ld live at all4 ,x is true t bact]ia1 by produc+ disease1 once 9 a :ile cause ! premature dea? ( an individual2 once 9 a :ile1 inde$1 !y may sweep (f a hundr$ or a ?\s& individuals2 b x is equally true t )\t !m plant & animal life w\ld be impossible on ! face ( ! e>?4