a history of science-4-第36节

按键盘上方向键 ← 或 → 可快速上下翻页，按键盘上的 Enter 键可回到本书目录页，按键盘上方向键 ↑ 可回到本页顶部！
————未阅读完？加入书签已便下次继续阅读！


omplished　better　by　simple　means　than　by　the　heroic　measures　hitherto　thought　necessary。　　In　a　word；　scientific　empiricism　was　beginning　to　gain　a　hearing　in　medicine　as　against　the　metaphysical　preconceptions　of　the　earlier　generations。


PARASITIC　DISEASES

I　have　just　adverted　to　the　fact　that　Napoleon　Bonaparte；　as　First　Consul　and　as　Emperor；　was　the　victim　of　a　malady　which　caused　him　to　seek　the　advice　of　the　most　distinguished　physicians　of　Paris。　　It　is　a　little　shocking　to　modern　sensibilities　to　read　that　these　physicians；　except　Corvisart；　diagnosed　the　distinguished　patient's　malady　as　〃gale　repercutee〃that　is　to　say；　in　idiomatic　English；　the　itch　〃struck　in。〃　It　is　hardly　necessary　to　say　that　no　physician　of　today　would　make　so　inconsiderate　a　diagnosis　in　the　case　of　a　royal　patient。　If　by　any　chance　a　distinguished　patient　were　afflicted　with　the　itch；　the　sagacious　physician　would　carefully　hide　the　fact　behind　circumlocutions　and　proceed　to　eradicate　the　disease　with　all　despatch。　　That　the　physicians　of　Napoleon　did　otherwise　is　evidence　that　at　the　beginning　of　the　century　the　disease　in　question　enjoyed　a　very　different　status。　　At　that　time　itch；　instead　of　being　a　most　plebeian　malady；　was；　so　to　say；　a　court　disease。　It　enjoyed　a　circulation；　in　high　circles　and　in　low；　that　modern　therapeutics　has　quite　denied　it；　and　the　physicians　of　the　time　gave　it　a　fictitious　added　importance　by　ascribing　to　its　influence　the　existence　of　almost　any　obscure　malady　that　came　under　their　observation。　Long　after　Napoleon's　time　gale　continued　to　hold　this　proud　distinction。　For　example；　the　imaginative　Dr。　Hahnemann　did　not　hesitate　to　affirm；　as　a　positive　maxim；　that　three…fourths　of　all　the　ills　that　flesh　is　heir　to　were　in　reality　nothing　but　various　forms　of　〃gale　repercutee。〃

All　of　which　goes　to　show　how　easy　it　may　be　for　a　masked　pretender　to　impose　on　credulous　humanity；　for　nothing　is　more　clearly　established　in　modern　knowledge　than　the　fact　that　〃gale　repercutee〃　was　simply　a　name　to　hide　a　profound　ignorance；　no　such　disease　exists　or　ever　did　exist。　　Gale　itself　is　a　sufficiently　tangible　reality；　to　be　sure；　but　it　is　a　purely　local　disease　of　the　skin；　due　to　a　perfectly　definite　cause；　and　the　dire　internal　conditions　formerly　ascribed　to　it　have　really　no　causal　connection　with　it　whatever。　This　definite　cause；　as　every　one　nowadays　knows；　is　nothing　more　or　less　than　a　microscopic　insect　which　has　found　lodgment　on　the　skin；　and　has　burrowed　and　made　itself　at　home　there。　Kill　that　insect　and　the　disease　is　no　more；　hence　it　has　come　to　be　an　axiom　with　the　modern　physician　that　the　itch　is　one　of　the　three　or　four　diseases　that　he　positively　is　able　to　cure；　and　that　very　speedily。　　But　it　was　far　otherwise　with　the　physicians　of　the　first　third　of　our　century；　because　to　them　the　cause　of　the　disease　was　an　absolute　mystery。

It　is　true　that　here　and　there　a　physician　had　claimed　to　find　an　insect　lodged　in　the　skin　of　a　sufferer　from　itch；　and　two　or　three　times　the　claim　had　been　made　that　this　was　the　cause　of　the　malady；　but　such　views　were　quite　ignored　by　the　general　profession；　and　in　1833　it　was　stated　in　an　authoritative　medical　treatise　that　the　〃cause　of　gale　is　absolutely　unknown。〃　　But　even　at　this　time；　as　it　curiously　happened；　there　were　certain　ignorant　laymen　who　had　attained　to　a　bit　of　medical　knowledge　that　was　withheld　from　the　inner　circles　of　the　profession。　As　the　peasantry　of　England　before　Jenner　had　known　of　the　curative　value　of　cow…pox　over　small…pox；　so　the　peasant　women　of　Poland　had　learned　that　the　annoying　skin　disease　from　which　they　suffered　was　caused　by　an　almost　invisible　insect；　and；　furthermore；　had　acquired　the　trick　of　dislodging　the　pestiferous　little　creature　with　the　point　of　a　needle。　　From　them　a　youth　of　the　country；　F。　Renucci　by　name；　learned　the　open　secret。　He　conveyed　it　to　Paris　when　he　went　there　to　study　medicine；　and　in　1834　demonstrated　it　to　his　master　Alibert。　　This　physician；　at　first　sceptical；　soon　was　convinced；　and　gave　out　the　discovery　to　the　medical　world　with　an　authority　that　led　to　early　acceptance。

Now　the　importance　of　all　this；　in　the　present　connection；　is　not　at　all　that　it　gave　the　clew　to　the　method　of　cure　of　a　single　disease。　What　makes　the　discovery　epochal　is　the　fact　that　it　dropped　a　brand…new　idea　into　the　medical　ranksan　idea　destined；　in　the　long…run；　to　prove　itself　a　veritable　bombthe　idea；　namely；　that　a　minute　and　quite　unsuspected　animal　parasite　may　be　the　cause　of　a　well…known；　widely　prevalent；　and　important　human　disease。　Of　course　the　full　force　of　this　idea　could　only　be　appreciated　in　the　light　of　later　knowledge；　but　even　at　the　time　of　its　coming　it　sufficed　to　give　a　great　impetus　to　that　new　medical　knowledge；　based　on　microscopical　studies；　which　had　but　recently　been　made　accessible　by　the　inventions　of　the　lens…makers。　The　new　knowledge　clarified　one　very　turbid　medical　pool　and　pointed　the　way　to　the　clarification　of　many　others。

Almost　at　the　same　time　that　the　Polish　medical　student　was　demonstrating　the　itch　mite　in　Paris；　it　chanced；　curiously　enough；　that　another　medical　student；　this　time　an　Englishman；　made　an　analogous　discovery　of　perhaps　even　greater　importance。　　Indeed；　this　English　discovery　in　its　initial　stages　slightly　antedated　the　other；　for　it　was　in　1833　that　the　student　in　question；　James　Paget；　interne　in　St。　Bartholomew's　Hospital；　London；　while　dissecting　the　muscular　tissues　of　a　human　subject；　found　little　specks　of　extraneous　matter；　which；　when　taken　to　the　professor　of　comparative　anatomy；　Richard　Owen；　were　ascertained；　with　the　aid　of　the　microscope；　to　be　the　cocoon　of　a　minute　and　hitherto　unknown　insect。　Owen　named　the　insect　Trichina　spiralis。　　After　the　discovery　was　published　it　transpired　that　similar　specks　had　been　observed　by　several　earlier　investigators；　but　no　one　had　previously　suspected　or；　at　any　rate；　demonstrated　their　nature。　　Nor　was　the　full　story　of　the　trichina　made　out　for　a　long　time　after　Owen's　discovery。　It　was　not　till　1847　that　the　American　anatomist　Dr。　Joseph　Leidy　found　the　cysts　of　trichina　in　the　tissues　of　pork；　and　another　decade　or　so　elapsed　after　that　before　German　workers；　chief　among　whom　were　Leuckart；　Virchow；　and　Zenker；　proved　that　the　parasite　gets　into　the　human　system　through　ingestion　of　infected　pork；　and　that　it　causes　a　definite　set　of　symptoms　of　disease　which　hitherto　had　been　mistaken　for　rheumatism；　typhoid　fever；　and　other　maladies。　Then　the　medical　world　was　agog　for　a　time　over　the　subject　of　trichinosis；　government　inspection　of　pork　was　established　in　some　parts　of　Germany；　American　pork　was　excluded　altogether　from　France；　and　the　whole　subject　thus　came　prominently　to　public　attention。　But　important　as　the　trichina　parasite　proved　on　its　own　account　in　the　end；　its　greatest　importance；　after　all；　was　in　the　share　it　played　in　directing　attention　at　the　time　of　its　discovery　in　1833　to　the　subject　of　microscopic　parasites　in　general。

The　decade　that　followed　that　discovery　was　a　time　of　great　activity　in　the　study　of　microscopic　organisms　and　microscopic　tissues；　and　such　men　as　Ehrenberg　and　Henle　and　Bory　Saint…Vincent　and　Kolliker　and　Rokitansky　and　Remak　and　Dujardin　were　widening　the　bounds　of　knowledge　of　this　new　subject　with　details　that　cannot　be　more　than　referred　to　here。　But　the　crowning　achievement　of　the　period　in　this　direction　was　the　discovery　made　by　the　German；　J。　L。　Schoenlein；　in　1839；　that　a　very　common　and　most　distressing　disease　of　the　scalp；　known　as　favus；　is　really　due　to　the　presence　and　growth　on　the　scalp　of　a　vegetable　organism　of　microscopic　size。　　Thus　it　was　made　clear　that　not　merely　animal　but　also　vegetable　organisms　of　obscure；　microscopic　species　have　causal　relations　to　the　diseases　with　which　mankind　is　afflicted。　This　knowledge　of　the　parasites　was　another　long　step　in　the　direction　of　scientific　medical　knowledge；　but　the　heights　to　which　this　knowledge　led　were　not　to　be　scaled；　or　even　recognized；　until　another　generation　of　workers　had　entered　the　field。


PAINLESS　SURGERY

Meantime；　in　quite　another　field　of　medicine；　events　were　developing　which　led　presently　to　a　revelation　of　greater　immediate　importance　to　humanity　than　any　other　discovery　that　had　come　in　the　century；　perhaps　in　any　field　of　science　whatever。　This　was　the　discovery　of　the　pain…dispelling　power　of　the　vapor　of　sulphuric　ether　inhaled　by　a　patient　undergoing　a　surgical　operation。　This　discovery　came　solely　out　of　America；　and　it　stands　curiously　isolated；　since　apparently　no　minds　in　any　other　country　were　trending　towards　it　even　vaguely。　　Davy；　in　England；　had　indeed　originated　the　method　of　medication　by　inhalation；　and　earned　out　some　most　interesting　experiments　fifty　years　earlier；　and　it　was　doubtless　his　experiments　with　nitrous　oxide　gas　that　gave　the　clew　to　one　of　the　American　investigators；　but　this　was　the　sole　contribution　of　preceding　generations　to　the　subject；　and　since　the　beginning　of　the　century；　when　Davy　turned　his　attention　to　other　matters；　no　one　had　made　the　slightest　advance　along　the　same　line　until　an　American　dentist　renewed　the　invest