a history of science-2-第29章

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was　founded；　under　the　leadership　of　Professor　J。　C。　Sturm。　The　early　labors　of　this　society　were　devoted　to　a　repetition　of　the　most　notable　experiments　of　the　time；　and　the　work　of　the　embryo　society　was　published　in　two　volumes；　in　1672　and　1685　respectively；　which　were　practically　text…books　of　the　physics　of　the　period。　It　was　not　until　1700　that　Frederick　I。　founded　the　Royal　Academy　of　Sciences　at　Berlin；　after　the　elaborate　plan　of　Leibnitz；　who　was　himself　the　first　president。　Perhaps　the　nearest　realization　of　Bacon's　ideal；　however；　is　in　the　Royal　Academy　of　Sciences　at　Paris；　which　was　founded　in　1666　under　the　administration　of　Colbert；　during　the　reign　of　Louis　XIV。　This　institution　not　only　recognized　independent　members；　but　had　besides　twenty　pensionnaires　who　received　salaries　from　the　government。　In　this　way　a　select　body　of　scientists　were　enabled　to　pursue　their　investigations　without　being　obliged　to　〃give　thought　to　the　morrow〃　for　their　sustenance。　In　return　they　were　to　furnish　the　meetings　with　scientific　memoirs；　and　once　a　year　give　an　account　of　the　work　they　were　engaged　upon。　Thus　a　certain　number　of　the　brightest　minds　were　encouraged　to　devote　their　entire　time　to　scientific　research；　〃delivered　alike　from　the　temptations　of　wealth　or　the　embarrassments　of　poverty。〃　That　such　a　plan　works　well　is　amply　attested　by　the　results　emanating　from　the　French　academy。　Pensionnaires　in　various　branches　of　science；　however；　either　paid　by　the　state　or　by　learned　societies；　are　no　longer　confined　to　France。　Among　the　other　early　scientific　societies　was　the　Imperial　Academy　of　Sciences　at　St。　Petersburg；　projected　by　Peter　the　Great；　and　established　by　his　widow；　Catharine　I。；　in　1725；　and　also　the　Royal　Swedish　Academy；　incorporated　in　1781；　and　counting　among　its　early　members　such　men　as　the　celebrated　Linnaeus。　But　after　the　first　impulse　had　resulted　in　a　few　learned　societies；　their　manifest　advantage　was　so　evident　that　additional　numbers　increased　rapidly；　until　at　present　almost　every　branch　of　every　science　is　represented　by　more　or　less　important　bodies；　and　these　are；　individually　and　collectively；　adding　to　knowledge　and　stimulating　interest　in　the　many　fields　of　science；　thus　vindicating　Lord　Bacon's　asseverations　that　knowledge　could　be　satisfactorily　promulgated　in　this　manner。

X。　THE　SUCCESSORS　OF　GALILEO　IN　PHYSICAL　SCIENCE　We　have　now　to　witness　the　diversified　efforts　of　a　company　of　men　who；　working　for　the　most　part　independently；　greatly　added　to　the　data　of　the　physical　sciencessuch　men　as　Boyle；　Huygens；　Von　Gericke；　and　Hooke。　It　will　be　found　that　the　studies　of　these　men　covered　the　whole　field　of　physical　sciences　as　then　understoodthe　field　of　so…called　natural　philosophy。　We　shall　best　treat　these　successors　of　Galileo　and　precursors　of　Newton　somewhat　biographically；　pointing　out　the　correspondences　and　differences　between　their　various　accomplishments　as　we　proceed。　It　will　be　noted　in　due　course　that　the　work　of　some　of　them　was　anticipatory　of　great　achievements　of　a　later　century。

ROBERT　BOYLE　（1627…1691）　Some　of　Robert　Boyle's　views　as　to　the　possible　structure　of　atmospheric　air　will　be　considered　a　little　farther　on　in　this　chapter；　but　for　the　moment　we　will　take　up　the　consideration　of　some　of　his　experiments　upon　that　as　well　as　other　gases。　Boyle　was　always　much　interested　in　alchemy；　and　carried　on　extensive　experiments　in　attempting　to　accomplish　the　transmutation　of　metals；　but　he　did　not　confine　himself　to　these　experiments；　devoting　himself　to　researches　in　all　the　fields　of　natural　philosophy。　He　was　associated　at　Oxford　with　a　company　of　scientists；　including　Wallis　and　Wren；　who　held　meetings　and　made　experiments　together；　these　gatherings　being　the　beginning；　as　mentioned　a　moment　ago；　of　what　finally　became　the　Royal　Society。　It　was　during　this　residence　at　Oxford　that　many　of　his　valuable　researches　upon　air　were　made；　and　during　this　time　be　invented　his　air…pump；　now　exhibited　in　the　Royal　Society　rooms　at　Burlington　House。＇1＇　His　experiments　to　prove　the　atmospheric　pressure　are　most　interesting　and　conclusive。　〃Having　three　small；　round　glass　bubbles；　blown　at　the　flame　of　a　lamp；　about　the　size　of　hazel…nuts；〃　he　says；　〃each　of　them　with　a　short；　slender　stem；　by　means　whereof　they　were　so　exactly　poised　in　water　that　a　very　small　change　of　weight　would　make　them　either　emerge　or　sink；　at　a　time　when　the　atmosphere　was　of　convenient　weight；　I　put　them　into　a　wide…mouthed　glass　of　common　water；　and　leaving　them　in　a　quiet　place；　where　they　were　frequently　in　my　eye；　I　observed　that　sometimes　they　would　be　at　the　top　of　the　water；　and　remain　there　for　several　days；　or　perhaps　weeks；　together；　and　sometimes　fall　to　the　bottom；　and　after　having　continued　there　for　some　time　rise　again。　And　sometimes　they　would　rise　or　fall　as　the　air　was　hot　or　cold。〃＇2＇　It　was　in　the　course　of　these　experiments　that　the　observations　made　by　Boyle　led　to　the　invention　of　his　〃statical　barometer；〃　the　mercurial　barometer　having　been　invented；　as　we　have　seen；　by　Torricelli；　in　1643。　In　describing　this　invention　he　says：　〃Making　choice　of　a　large；　thin；　and　light　glass　bubble；　blown　at　the　flame　of　a　lamp；　I　counterpoised　it　with　a　metallic　weight；　in　a　pair　of　scales　that　were　suspended　in　a　frame；　that　would　turn　with　the　thirtieth　part　of　a　grain。　Both　the　frame　and　the　balance　were　then　placed　near　a　good　barometer；　whence　I　might　learn　the　present　weight　of　the　atmosphere；　when；　though　the　scales　were　unable　to　show　all　the　variations　that　appeared　in　the　mercurial　barometer；　yet　they　gave　notice　of　those　that　altered　the　height　of　the　mercury　half　a　quarter　of　an　inch。〃＇3＇　A　fairly　sensitive　barometer；　after　all。　This　statical　barometer　suggested　several　useful　applications　to　the　fertile　imagination　of　its　inventor；　among　others　the　measuring　of　mountain…peaks；　as　with　the　mercurial　barometer；　the　rarefication　of　the　air　at　the　top　giving　a　definite　ratio　to　the　more　condensed　air　in　the　valley。　Another　of　his　experiments　was　made　to　discover　the　atmospheric　pressure　to　the　square　inch。　After　considerable　difficulty　he　determined　that　the　relative　weight　of　a　cubic　inch　of　water　and　mercury　was　about　one　to　fourteen；　and　computing　from　other　known　weights　he　determined　that　〃when　a　column　of　quicksilver　thirty　inches　high　is　sustained　in　the　barometer；　as　it　frequently　happens；　a　column　of　air　that　presses　upon　an　inch　square　near　the　surface　of　the　earth　must　weigh　about　fifteen　avoirdupois　pounds。〃＇4＇　As　the　pressure　of　air　at　the　sea…level　is　now　estimated　at　14。7304　pounds　to　the　square　inch；　it　will　be　seen　that　Boyle's　calculation　was　not　far　wrong。　From　his　numerous　experiments　upon　the　air；　Boyle　was　led　to　believe　that　there　were　many　〃latent　qualities〃　due　to　substances　contained　in　it　that　science　had　as　yet　been　unable　to　fathom；　believing　that　there　is　〃not　a　more　heterogeneous　body　in　the　world。〃　He　believed　that　contagious　diseases　were　carried　by　the　air；　and　suggested　that　eruptions　of　the　earth；　such　as　those　made　by　earthquakes；　might　send　up　〃venomous　exhalations〃　that　produced　diseases。　He　suggested　also　that　the　air　might　play　an　important　part　in　some　processes　of　calcination；　which；　as　we　shall　see；　was　proved　to　be　true　by　Lavoisier　late　in　the　eighteenth　century。　Boyle's　notions　of　the　exact　chemical　action　in　these　phenomena　were　of　course　vague　and　indefinite；　but　he　had　observed　that　some　part　was　played　by　the　air；　and　he　was　right　in　supposing　that　the　air　〃may　have　a　great　share　in　varying　the　salts　obtainable　from　calcined　vitriol。〃＇5＇　Although　he　was　himself　such　a　painstaking　observer　of　facts；　he　had　the　fault　of　his　age　of　placing　too　much　faith　in　hear…say　evidence　of　untrained　observers。　Thus；　from　the　numerous　stories　he　heard　concerning　the　growth　of　metals　in　previously　exhausted　mines；　he　believed　that　the　air　was　responsible　for　producing　this　growthin　which　he　undoubtedly　believed。　The　story　of　a　tin…miner　that；　in　his　own　time；　after　a　lapse　of　only　twenty…five　years；　a　heap；　of　earth　previously　exhausted　of　its　ore　became　again　even　more　richly　impregnated　than　before　by　lying　exposed　to　the　air；　seems　to　have　been　believed　by　the　philosopher。　As　Boyle　was　an　alchemist；　and　undoubtedly　believed　in　the　alchemic　theory　that　metals　have　〃spirits〃　and　various　other　qualities　that　do　not　exist；　it　is　not　surprising　that　he　was　credulous　in　the　matter　of　beliefs　concerning　peculiar　phenomena　exhibited　by　them。　Furthermore；　he　undoubtedly　fell　into　the　error　common　to　〃specialists；〃　or　persons　working　for　long　periods　of　time　on　one　subjectthe　error　of　over…enthusiasm　in　his　subject。　He　had　discovered　so　many　remarkable　qualities　in　the　air　that　it　is　not　surprising　to　find　that　he　attributed　to　it　many　more　that　he　could　not　demonstrate。　Boyle's　work　upon　colors；　although　probably　of　less　importance　than　his　experiments　and　deductions　upon　air；　show　that　he　was　in　the　van　as　far　as　the　science　of　his　day　was　concerned。　As　he　points　out；　the　schools　of　his　time　generally　taught　that　〃color　is　a　penetrating　quality；　reaching　to　the　innermost　part　of　the　substance；〃　and；　as　an　example　of　this；　sealing…wax　was　cited；　which　could　be　broken　into　minute　bits；　each　particle　retaining　the　same　color　as　its　fellows　or　the　original　mass。　To　refute　this　theory；　and　to　show　instances　to　the　contrary；　Boyle；　among　other　things；　shows　that　various　colorsblue；　red；　yellowmay　be　produced　upon　tempered　steel；　and　yet　the　metal　within　〃a　hair's…breadth　of　its　surface〃　have　none　of　these　colors。　Therefore；　he　was　led　to　believe　that　color；　in　opaque　bodies　at　least；　is　superficial。　〃But　before　we　descend　to　a　more　particular　consideration　of　our　subject；〃　he　says；　〃　'tis　proper　to　observe　that　colors　may　be　regarded　either　as　a　quality　residing　in　bodies　to　modify　light　after　a　particular　manner；　or　else　as　light　itself　so　modified　as　to　strike　upon　the　organs　of　sight；　and　cause　the　sensation　we　call　color；　and　that　this　latter　is　the　more　proper　acceptation　of　the　word　color　will　appear　hereafter。　And　indeed　it　is　the　light　itself；　which　after　a　certain　manner；　either　mixed　with　shades　or　other…wise；　strikes　our　eyes　and　immediately　produces　that　motion　in　the　organ　which　gives　us　the　color　of　an　object。〃＇6＇　In　examining　smooth　and　rough　surfaces　to　determine　the　cause　of　their　color；　he　made　use　of　the　microscope；　and　pointed　out　the　very　obvious　example　of　the　difference　in　color　of　a　rough　and　a　polished　piece　of　the　same　block　of　stone。　He　used　some　striking　illustrations　of　the　effect　of　light　and　the　position　of　the　eye　upon　colors。　〃Thus　the　color　of　plush　or　velvet　will　appear　various　if　you　stroke　part　of　it　one　way　and　part　another；　the　posture　of　the　particular　threads　in　regard　to　the　light；　or　the　eye；　being　thereby　varied。　And　'tis　observable　that　in　a　field　of　ripe　corn；　blown　upon　by　the　wind；　there　will　appear　waves　of　a　color　different　from　that　of　the　rest　of　the　corn；　because　the　wind；　by　depressing　some　of　the　ears　more　than　others；　causes　one　to　reflect　more　light　from　the　lateral　and　strawy　parts　than　another。〃＇7＇　His　work　upon　color；　however；　as　upon　light；　was　entirely　overshadowed　by　the　work　of　his　great　fellow…countryman　Newt