QQ. 



ON SPONTANEOUS EVAPORATION. 



Tnhle r f the 

 spon^niieous 

 evaporation of 

 water at ilitrcr- 

 rnt tempera- 



1 



c 



i 



Daily evaporation 

 ob erved. 



Daily e a,;oriition 

 bv the rule. 



c5 



1 



H 



1 



u. 



.2 



ll 



a 

 .2 



11 



> r- 



— £ 

 Q 



i 



c 

 Q 



0°'3'2" 



4-4 



4-4 







16° 



68° 



17-8 



18-7 



+ 0-9 



1 



34-25 



4-5 



4-8 



+ o-q 



17 



70-25 



19-4 



20-5 



+ 1-1" 



o 



36-5 



4-4 



5-.S 



-1- 0-9 



18 



72-5 



22 



22-4(+ 0-4| 



3 



38-75 



5-;v 



5-8 



— 01 



19 



74-75 



24-8 24-6|~ 0-2| 



4 



41 



6-8 



6-3 



— 0-.5 



20 



77 



27-3 



26-9 —0-4 



5 



43-25 



7-3 



6-9 



— 0-4 



21 



79-25 



30-2 



29-4 — 0-8 



6' 



45-5 



7-4 



7-6 



+ 0-^ 



22 



81-5 



32 



3 2-2J+ 0-2 



7 



47-75 



8 



8-3 



+ 0-3 



23 



83-75 



35-6 



35-2 —0-4 



8 



50 



9-6 



9-1 —0-5 



24 



86 38-9 



38-6 



— 0-3 



9 



52-25 



J 0-3 



9-9 — 0-4 



25 



88-25 42 



42-2 



+ 0-2 



10 



54-5 



10 



10-9 + 0-9 



26 



90-5 I46-8 



46-2 



— 0-6 



n 



56-75 



10-9 



11-9+ 1 



27 



92-75 51 !50-6 



— 0-4 



12 ;5.9 



13-2 



13 



— 0-2 



28 



95 



55-7155-4 



— 0-3 



13 61-25 



14 



14-3 



+ 0-3 



29 



97-25 



61 |60-7 



— 0-3 



14 \63-5 



15-9 



15-6 



— 0-3 



30 



99-5 



b6-pj66-4 



— 0-5 



15 165-75 



16-4 



17-1 +0-7lj 



31 



101-75 



72-7|72-7| 







Thediffe-cnccs If wc examine the differences in the fifth column, we 

 owing to inac g^j^ij f^.^^]]y perceive, 1, that these differences are verv 



cu:icies m the . . "^ 



experiments, small; 2, that they are indifferently positive or negative ; 

 and, 3, that their sum is next to nothing : whence it follows, 

 that these slight differences may reasonably be ascribed to 

 the errours iinavoidzible in experiments of tliis kind ; and 

 that, without these errours, the evaporations observed would 

 have coincided with thoi>e calculated according to our hypo- 

 thesis, which may consequently be considered as perfectly 

 conf('iinable to nature. 



I^rom the preceding experiments therefore we may infer 

 this remarkable law, that, while the degrees of heat increase 

 or diminish in arithmetical progression, the correspondint^ 

 evaporations itici ease or diminish in geometrical progression. 

 Tluis, the heal in our experiments increasing uniformly and 

 su. cissively one degree [2-25" F.], the corresponding eva- 

 porations form a geometrical progression, each term of 

 which is to the preceding in the ratio of 1'0947 to 1. So 

 these evaporations form a geometrical progression nearly 



in 



Evaporation 

 increase, in a 

 grometrical 

 progression. 



