meteorology-第31章

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river　and　causes　the　moisture　to　evaporate　with　it；　as　in　the　case



of　honey　when　it　has　been　heated　and　is　immersed　in　water。）　Some　of



these　bodies　cannot　be　melted　or　softened；　for　instance；　amber　and



certain　stones；　e。g。　the　stalactites　in　caves。　（For　these　stalactites；



too；　are　formed　in　the　same　way：　the　agent　is　not　fire；　but　cold　which



drives　out　the　heat；　which；　as　it　leaves　the　body；　draws　out　the



moisture　with　it：　in　the　other　class　of　bodies　the　agent　is　external



fire。）　In　those　from　which　the　moisture　has　not　wholly　gone　earth



still　preponderates；　but　they　admit　of　softening　by　heat；　e。g。　iron



and　horn。



　　Now　since　we　must　include　among　'meltables'　those　bodies　which　are



melted　by　fire；　these　contain　some　water：　indeed　some　of　them；　like



wax；　are　common　to　earth　and　water　alike。　But　those　that　are　melted　by



water　are　of　earth。　Those　that　are　not　melted　either　by　fire　or



water　are　of　earth；　or　of　earth　and　water。



　　Since；　then；　all　bodies　are　either　liquid　or　solid；　and　since　the



things　that　display　the　affections　we　have　enumerated　belong　to



these　two　classes　and　there　is　nothing　intermediate；　it　follows　that



we　have　given　a　complete　account　of　the　criteria　for　distinguishing



whether　a　body　consists　of　earth　or　of　water　or　of　more　elements



than　one；　and　whether　fire　was　the　agent　in　its　formation；　or　cold；　or



both。



　　Gold；　then；　and　silver　and　copper　and　tin　and　lead　and　glass　and



many　nameless　stone　are　of　water：　for　they　are　all　melted　by　heat。



Of　water；　too；　are　some　wines　and　urine　and　vinegar　and　lye　and　whey



and　serum：　for　they　are　all　congealed　by　cold。　In　iron；　horn；　nails；



bones；　sinews；　wood；　hair；　leaves；　bark；　earth　preponderates。　So；　too；



in　amber；　myrrh；　frankincense；　and　all　the　substances　called



'tears'；　and　stalactites；　and　fruits；　such　as　leguminous　plants　and



corn。　For　things　of　this　kind　are；　to　a　greater　or　less　degree；　of



earth。　For　of　all　these　bodies　some　admit　of　softening　by　heat；　the



rest　give　off　fumes　and　are　formed　by　refrigeration。　So　again　in



natron；　salt；　and　those　kinds　of　stones　that　are　not　formed　by



refrigeration　and　cannot　be　melted。　Blood；　on　the　other　hand；　and



semen；　are　made　up　of　earth　and　water　and　air。　If　the　blood　contains



fibres；　earth　preponderates　in　it：　consequently　its　solidifies　by



refrigeration　and　is　melted　by　liquids；　if　not；　it　is　of　water　and



therefore　does　not　solidify。　Semen　solidifies　by　refrigeration；　its



moisture　leaving　it　together　with　its　heat。







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　　We　must　investigate　in　the　light　of　the　results　we　have　arrived　at



what　solid　or　liquid　bodies　are　hot　and　what　cold。



　　Bodies　consisting　of　water　are　commonly　cold；　unless　（like　lye；



urine；　wine）　they　contain　foreign　heat。　Bodies　consisting　of　earth；　on



the　other　hand；　are　commonly　hot　because　heat　was　active　in　forming



them：　for　instance　lime　and　ashes。



　　We　must　recognize　that　cold　is　in　a　sense　the　matter　of　bodies。



For　the　dry　and　the　moist　are　matter　（being　passive）　and　earth　and



water　are　the　elements　that　primarily　embody　them；　and　they　are



characterized　by　cold。　Consequently　cold　must　predominate　in　every



body　that　consists　of　one　or　other　of　the　elements　simply；　unless　such



a　body　contains　foreign　heat　as　water　does　when　it　boils　or　when　it



has　been　strained　through　ashes。　This　latter；　too；　has　acquired　heat



from　the　ashes；　for　everything　that　has　been　burnt　contains　more　or



less　heat。　This　explains　the　generation　of　animals　in　putrefying



bodies：　the　putrefying　body　contains　the　heat　which　destroyed　its



proper　heat。



　　Bodies　made　up　of　earth　and　water　are　hot；　for　most　of　them　derive



their　existence　from　concoction　and　heat；　though　some；　like　the



waste　products　of　the　body；　are　products　of　putrefaction。　Thus



blood；　semen；　marrow；　figjuice；　and　all　things　of　the　kinds　are　hot　as



long　as　they　are　in　their　natural　state；　but　when　they　perish　and　fall



away　from　that　state　they　are　so　no　longer。　For　what　is　left　of　them



is　their　matter　and　that　is　earth　and　water。　Hence　both　views　are　held



about　them；　some　people　maintaining　them　to　be　cold　and　others　to　be



warm；　for　they　are　observed　to　be　hot　when　they　are　in　their　natural



state；　but　to　solidify　when　they　have　fallen　away　from　it。　That；　then；



is　the　case　of　mixed　bodies。　However；　the　distinction　we　laid　down



holds　good：　if　its　matter　is　predominantly　water　a　body　is　cold　（water



being　the　complete　opposite　of　fire）；　but　if　earth　or　air　it　tends



to　be　warm。



　　It　sometimes　happens　that　the　coldest　bodies　can　be　raised　to　the



highest　temperature　by　foreign　heat；　for　the　most　solid　and　the



hardest　bodies　are　coldest　when　deprived　of　heat　and　most　burning



after　exposure　to　fire：　thus　water　is　more　burning　than　smoke　and



stone　than　water。



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　　Having　explained　all　this　we　must　describe　the　nature　of　flesh；



bone；　and　the　other　homogeneous　bodies　severally。



　　Our　account　of　the　formation　of　the　homogeneous　bodies　has　given



us　the　elements　out　of　which　they　are　compounded　and　the　classes



into　which　they　fall；　and　has　made　it　clear　to　which　class　each　of



those　bodies　belongs。　The　homogeneous　bodies　are　made　up　of　the



elements；　and　all　the　works　of　nature　in　turn　of　the　homogeneous



bodies　as　matter。　All　the　homogeneous　bodies　consist　of　the　elements



described；　as　matter；　but　their　essential　nature　is　determined　by



their　definition。　This　fact　is　always　clearer　in　the　case　of　the　later



products　of　those；　in　fact；　that　are　instruments；　as　it　were；　and　have



an　end：　it　is　clearer；　for　instance；　that　a　dead　man　is　a　man　only



in　name。　And　so　the　hand　of　a　dead　man；　too；　will　in　the　same　way　be　a



hand　in　name　only；　just　as　stone　flutes　might　still　be　called



flutes：　for　these　members；　too；　are　instruments　of　a　kind。　But　in



the　case　of　flesh　and　bone　the　fact　is　not　so　clear　to　see；　and　in



that　of　fire　and　water　even　less。　For　the　end　is　least　obvious　there



where　matter　predominates　most。　If　you　take　the　extremes；　matter　is



pure　matter　and　the　essence　is　pure　definition；　but　the　bodies



intermediate　between　the　two　are　matter　or　definition　in　proportion　as



they　are　near　to　either。　For　each　of　those　elements　has　an　end　and



is　not　water　or　fire　in　any　and　every　condition　of　itself；　just　as



flesh　is　not　flesh　nor　viscera　viscera；　and　the　same　is　true　in　a



higher　degree　with　face　and　hand。　What　a　thing　is　always　determined　by



its　function：　a　thing　really　is　itself　when　it　can　perform　its



function；　an　eye；　for　instance；　when　it　can　see。　When　a　thing　cannot



do　so　it　is　that　thing　only　in　name；　like　a　dead　eye　or　one　made　of



stone；　just　as　a　wooden　saw　is　no　more　a　saw　than　one　in　a　picture。



The　same；　then；　is　true　of　flesh；　except　that　its　function　is　less



clear　than　that　of　the　tongue。　So；　too；　with　fire；　but　its　function　is



perhaps　even　harder　to　specify　by　physical　inquiry　than　that　of　flesh。



The　parts　of　plants；　and　inanimate　bodies　like　copper　and　silver；



are　in　the　same　case。　They　all　are　what　they　are　in　virtue　of　a



certain　power　of　action　or　passion…just　like　flesh　and　sinew。　But　we



cannot　state　their　form　accurately；　and　so　it　is　not　easy　to　tell　when



they　are　really　there　and　when　they　are　not　unless　the　body　is



thoroughly　corrupted　and　its　shape　only　remains。　So　ancient　corpses



suddenly　become　ashes　in　the　grave　and　very　old　fruit　preserves　its



shape　only　but　not　its　taste：　so；　too；　with　the　solids　that　form



from　milk。



　　Now　heat　and　cold　and　the　motions　they　set　up　as　the　bodies　are



solidified　by　the　hot　and　the　cold　are　sufficient　to　form　all　such



parts　as　are　the　homogeneous　bodies；　flesh；　bone；　hair；　sinew；　and　the



rest。　For　they　are　all　of　them　differentiated　by　the　various　qualities



enumerated