The Specific Heat of Non-conductors. 



43 



III. Founded on the same differential equations used 

 iDy Pape, Dr. Schuster has independently arrived at the 

 following formula : — 



where A0 is the fall of temp, in time AT during the period of 

 steady cooling at the temperature t". 



■t^ = maximum temperature reached in n time intervals. 

 to = temperature of enclosure. 

 t' = observed temperature made after a lapse of time T' after the 



introduction of the hot body. 

 <Ti and 0-2 = water values of the hot body and of the calorimeter 



and contents respectively. 

 On = time of reaching maximum. 



We now give an example where the value of C is calcu- 

 lated by these three different formulae : — 



Mass of rubber ... = 38-70 

 „ foil ...= 21-3 

 „ water ... = 299-2 



K = 3-67 + -l + -5 = 4-3. 

 Mass of perforated brass holder used as stirrer 12*30. 

 f=16°-97 



£tr' = 21-62 Room temp. 17" -5 

 T = 99° after two hours' heating 

 0-t = 22° 



T-0 = 77°. Rise = 5°-03. 

 Thermometer in water to length of 3 inches. 

 The value of v was negligable. 



Readings at \ minute intervals. 



reading . 



. ... 16-97 = 00 



1 „ 



. ... 19-50 = 01 



2 „ 



. ... 20-80 = 02 



3 „ 



21-30 = 03 



4 ,, 



. ... 21-58 = 04 



5 „ 



. ... 21-72 = 06 



6 „ 



. ... 21-78 = 06 



7 » 



. ... 21.79 = 07 



