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Vegetable Stanch. 



1 1 



*vsz 



i 



2160 fquarc inches, the quotient is 

 4_. part of a cubick inch perfpired off a fquarc 

 inch in twenty four hours. Therefore in 

 equal furfaces and equal times the man per- 

 fpires iv, the plant T 4-r, or as 5 o : 1 5 . 



Which excefs in the man is occasioned 

 by the very different degrees of heat in each : 

 For the heat of the plant cannot be greater 

 than the heat of the circum-ambicnt air, 

 which heat in fummer is from 25 to 3 5 de- 

 grees above the freezing point, (vide Exp. 

 20.) but the heat of the warmeft external 



parts of a man's body is 54 fuch degrees; 

 and the heat of the blood 64 degrees; 



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which is nearly equal to water heated to 

 fuch a degree, as a man can well bear to hold 

 his hand in, ftirring it about ; which heat is 

 fufficient to make a plentiful evaporation. 



£$u. Since then the perfpirations of equal 

 areas, in a man and a Sunflower, are to each 

 other as 165 : 50, or as 37 '• * 5 andfince the 

 degrees of heat are as 2 : 1 , muft not the fum 

 or quantity of the areas of the pores lying 

 in equal furfaces, in the man and Sunflower, 

 be as 16: 1 ? for it feems that the quantities 

 of the evaporated fluid will be as the degrees 

 of heat, and the furn of the areas of the pores 

 taken together. J Dr. 



