for the elastic force of Steam, 101 



With these values in the formula p=(a-{- bt) 6 the numbers in 

 the third column of Table I. were calculated ; the second 

 column contains M. Regnault's corresponding results, from his 

 Table at page 374 of vol. ii. : — 



Table I. 



' 



Temperature Centi- 

 grade by air- thermo- 

 meter. 



Elastic force of vapour 

 of alcohol by interpo- 

 lation formula. 



Calculation by Alex- 

 ander's formula. 





millims. 



millims. 





-20 



3-34 



2-237 





-10 



647 



5-674 









1270 



12-700 





+ 10 



24-23 



25-836 





20 



44-46 



48-748 





30 



78-52 



86-556 





40 



133-69 



146166 





50 



21990 



236-651 





60 



350-21 



369-665 





70 



54115 



559-887 





80 



812-91 



825-507 





90 



1189-30 



1188-750 





100 



1697-55 



1676-423 





no 



2367-64 



2320-517 





120 



3231-73 



3158-836 





130 



4323-00 



4235-640 





140 



5674-59 



5602-368 





150 



731840 



7318395 



The general accordance of the second and third columns 

 through the range of 170° Centigrade is, I think, sufficient to 

 warrant the conclusion that the elastic force of the vapour of 

 alcohol is represented by the formula p=(a + bt) 6 ; and further 

 research might furnish values of a and b which would produce 



greater accordance. 



Table II. 



Temperature Centi- 

 grade by air-thermo- 

 meter. 



Elastic force of vapour 

 of ether by interpola- 

 tion formula. 



Calculation by Alex- 

 ander's formula. 





millims. 



millims, 



-20 



68-90 



71-471 



-10 



114-72 



116-964 







184-39 



184-390 



+ 10 



286-83 



281-500 



20 



432-78 



417937 



30 



634-80 



605-528 



40 



90704 



858-585 



50 



1264-83 



1194-238 



60 



172501 



1632-774 



70 



2304-90 



2198-009 



80 



3022-79 



2917-681 



90 



3898-26 



3823-840 



100 



4953 30 



4953-296 



110 



6214-63 



6348 050 



120 



7719-20 



8055-800 



