meteorology-第27节

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little　fumigable　stuff　and　consequently　is　inflammable。



　　All　bodies　are　combustible　that　dissolve　into　ashes；　and　all



bodies　do　this　that　solidify　under　the　influence　either　of　heat　or



of　both　heat　and　cold；　for　we　find　that　all　these　bodies　are



mastered　by　fire。　Of　stones　the　precious　stone　called　carbuncle　is



least　amenable　to　fire。



　　Of　combustible　bodies　some　are　inflammable　and　some　are　not；　and



some　of　the　former　are　reduced　to　coals。　Those　are　called



'inflammable'　which　produce　flame　and　those　which　do　not　are　called



'non…inflammable'。　Those　fumigable　bodies　that　are　not　liquid　are



inflammable；　but　pitch；　oil；　wax　are　inflammable　in　conjunction　with



other　bodies　rather　than　by　themselves。　Most　inflammable　are　those



bodies　that　give　off　smoke。　Of　bodies　of　this　kind　those　that



contain　more　earth　than　smoke　are　apt　to　be　reduced　to　coals。　Some



bodies　that　can　be　melted　are　not　inflammable；　e。g。　copper；　and　some



bodies　that　cannot　be　melted　are　inflammable；　e。g。　wood；　and　some



bodies　can　be　melted　and　are　also　inflammable；　e。g。　frankincense。



The　reason　is　that　wood　has　its　moisture　all　together　and　this　is



continuous　throughout　and　so　it　burns　up：　whereas　copper　has　it　in



each　part　but　not　continuous；　and　insufficient　in　quantity　to　give



rise　to　flame。　In　frankincense　it　is　disposed　in　both　of　these　ways。



Fumigable　bodies　are　inflammable　when　earth　predominates　in　them　and



they　are　consequently　such　as　to　be　unable　to　melt。　These　are



inflammable　because　they　are　dry　like　fire。　When　this　dry　comes　to



be　hot　there　is　fire。　This　is　why　flame　is　burning　smoke　or　dry



exhalation。　The　fumes　of　wood　are　smoke；　those　of　wax　and　frankincense



and　such…like；　and　pitch　and　whatever　contains　pitch　or　such…like



are　sooty　smoke；　while　the　fumes　of　oil　and　oily　substances　are　a



greasy　steam；　so　are　those　of　all　substances　which　are　not　at　all



combustible　by　themselves　because　there　is　too　little　of　the　dry　in



them　（the　dry　being　the　means　by　which　the　transition　to　fire　is



effected）；　but　burn　very　readily　in　conjunction　with　something　else。



（For　the　fat　is　just　the　conjunction　of　the　oily　with　the　dry。）　So



those　bodies　that　give　off　fumes；　like　oil　and　pitch；　belong　rather　to



the　moist；　but　those　that　burn　to　the　dry。







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　　Homogeneous　bodies　differ　to　touch…by　these　affections　and



differences；　as　we　have　said。　They　also　differ　in　respect　of　their



smell；　taste；　and　colour。



　　By　homogeneous　bodies　I　mean；　for　instance；　'metals'；　gold；



copper；　silver；　tin；　iron；　stone；　and　everything　else　of　this　kind　and



the　bodies　that　are　extracted　from　them；　also　the　substances　found



in　animals　and　plants；　for　instance；　flesh；　bones；　sinew；　skin；



viscera；　hair；　fibres；　veins　（these　are　the　elements　of　which　the



non…homogeneous　bodies　like　the　face；　a　hand；　a　foot；　and　everything



of　that　kind　are　made　up）；　and　in　plants；　wood；　bark；　leaves；　roots；



and　the　rest　like　them。



　　The　homogeneous　bodies；　it　is　true；　are　constituted　by　a　different



cause；　but　the　matter　of　which　they　are　composed　is　the　dry　and　the



moist；　that　is；　water　and　earth　（for　these　bodies　exhibit　those



qualities　most　clearly）。　The　agents　are　the　hot　and　the　cold；　for　they



constitute　and　make　concrete　the　homogeneous　bodies　out　of　earth　and



water　as　matter。　Let　us　consider；　then；　which　of　the　homogeneous



bodies　are　made　of　earth　and　which　of　water；　and　which　of　both。



　　Of　organized　bodies　some　are　liquid；　some　soft；　some　hard。　The



soft　and　the　hard　are　constituted　by　a　process　of　solidification；　as



we　have　already　explained。



　　Those　liquids　that　go　off　in　vapour　are　made　of　water；　those　that　do



not　are　either　of　the　nature　of　earth；　or　a　mixture　either　of　earth



and　water；　like　milk；　or　of　earth　and　air；　like　wood；　or　of　water



and　air；　like　oil。　Those　liquids　which　are　thickened　by　heat　are　a



mixture。　（Wine　is　a　liquid　which　raises　a　difficulty：　for　it　is　both



liable　to　evaporation　and　it　also　thickens；　for　instance　new　wine



does。　The　reason　is　that　the　word　'wine'　is　ambiguous　and　different



'wines'　behave　in　different　ways。　New　wine　is　more　earthy　than　old；



and　for　this　reason　it　is　more　apt　to　be　thickened　by　heat　and　less



apt　to　be　congealed　by　cold。　For　it　contains　much　heat　and　a　great



proportion　of　earth；　as　in　Arcadia；　where　it　is　so　dried　up　in　its



skins　by　the　smoke　that　you　scrape　it　to　drink。　If　all　wine　has　some



sediment　in　it　then　it　will　belong　to　earth　or　to　water　according　to



the　quantity　of　the　sediment　it　possesses。）　The　liquids　that　are



thickened　by　cold　are　of　the　nature　of　earth；　those　that　are　thickened



either　by　heat　or　by　cold　consist　of　more　than　one　element；　like　oil



and　honey；　and　'sweet　wine'。



　　Of　solid　bodies　those　that　have　been　solidified　by　cold　are　of



water；　e。g。　ice；　snow；　hail；　hoar…frost。　Those　solidified　by　heat



are　of　earth；　e。g。　pottery；　cheese；　natron；　salt。　Some　bodies　are



solidified　by　both　heat　and　cold。　Of　this　kind　are　those　solidified　by



refrigeration；　that　is　by　the　privation　both　of　heat　and　of　the



moisture　which　departs　with　the　heat。　For　salt　and　the　bodies　that　are



purely　of　earth　solidify　by　the　privation　of　moisture　only；　ice　by



that　of　heat　only；　these　bodies　by　that　of　both。　So　both　the　active



qualities　and　both　kinds　of　matter　were　involved　in　the　process。　Of



these　bodies　those　from　which　all　the　moisture　has　gone　are　all　of



them　of　earth；　like　pottery　or　amber。　（For　amber；　also；　and　the　bodies



called　'tears'　are　formed　by　refrigeration；　like　myrrh；



frankincense；　gum。　Amber；　too；　appears　to　belong　to　this　class　of



things：　the　animals　enclosed　in　it　show　that　it　is　formed　by



solidification。　The　heat　is　driven　out　of　it　by　the　cold　of　the



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