352 Prof. Potter on the Laws of the Expansion of 



The Table annexed gives the observed and calculated results 

 only to five places of decimals, though M. Pierre's results are 

 given to nine places in his papers : — 



Temperature 

 by Centigrade 

 thermometer. 



Volumes of 

 aldehyde 

 observed. 



Volumes 

 calculated by 

 the formula. 



Differences. 



-20-69 



-12-50 



+ 1207 



16-54 



21-32 



0-96881 

 0-98053 

 102133 

 1-02995 

 1-03875 



0-96881 

 0-98077 

 102133 

 102959 

 1038/5 



•00000 

 + -00024 



•00000 

 -00036 



•ooooo 



The differences commence only in the fourth place of decimals, 

 and we need not search for more correct values of a, b> and c 2 . 



After examining the conformity of aldehyde to the law of 

 hyperbolic expansion, I have undertaken a few others of the 

 best-known liquids. The computations, otherwise somewhat 

 laborious, have in these cases been comparatively easy, since, the 

 constants a, b, c 2 having been determined from the first three 

 conditions taken up, the remainder of the experimental results 

 were found to give differences from the calculated values com- 

 mencing at the most in the fourth place of decimals, and gene- 

 rally with small numbers. 



For alcohol, taking the experimental volumes at the tempera- 

 tures -32°-22 C, 0° C, 76°-73 C, as given in the Table an- 

 nexed, I find as follows : — 



a = -3538069, 

 b = 617-5750, 

 c 2 = 399-0727. 



Temperature 



Volumes of 



Volumes cal- 





by Centigrade 



alcohol observed 



culated by the 



Differences. 



thermometer. 



being 1 at 0° C 



formula. 





-32-22 



•9679586 



•9679586 



•0000000 



-2702 



•9728477 



•9729130 



+ 0000653 



-15-44 



•9842263 



•9842386 



+ -0000123 



- 9-66 



•9900518 



•9900480 



-•0000038 



- 4-54 



•9952424 



•9952843 



+•0000419 



+ 6-98 



1-0075626 



1-0073869 



-•0001757 



704 



10076592 



10074512 



-•0002080 



16-93 



1-0183223 



1-0182139 



- -0001084 



22-86 



1 0244951 



10248389 



+ -0003438 



28-00 



1-0307472 



1-0306889 



- -0000583 



33-46 



10371362 



10370160 



- -0001202 



39-93 



1-0447938 



10446687 



- -0001251 



4752 



1 0535632 



10538667 



+ 0003035 



50-33 



1-0567636 



10573349 



+ 0005713 



56-26 



10641601 



10647672 



+ -0006071 



60-41 



1-0898872 



10700629 



+ 0001757 



73-70 



1-0878048 



1-0875652 



- -0002396 



7673 



10916758 



10916758 



•0000000 



