320 



Mr. H. H. Poole on the Rate of 



that the effect of the rise of temperature of the ice is only to 

 depress the zero, leaving the form of the curve unaltered. 

 The solution of this equation is 



c/ 



where 6 is a constant and e the base of the Neperian system 





 of logarithms. We can give and ^ such values that the 



experimental and exponential curves coincide at any two 

 points, and observe how they agree elsewhere. 



The table given SQ0W s readings obtained in the third 

 experiment. The figures in the third column are obtained 



by making O = 192'S and -^ = 0-0375; these values are chosen 



so as to make the observed and calculated values coincide at 

 the two points marked with an asterisk. 



Time, 



(observed), 



9 (calculated), 



Differences, 



hours. 



scale-divisions. 



scale-divisions. 



scale-divisions. 



o-o 



189-5 



190-9 



-1-4 



515 



1573 



157-0 



+0-3 



15-77 



104-2 



104-7 



-0 5 



17-02 



97-6 



97 6 



oo* 



24-67 



75-0 



74-5 



4-0-5 



28-98 



63-2 



63-1 



+0-1 



39-75 



41-7 



41-5 



+0-2 



52-52 



25-0 



24-9 



4-01 



63-77 



15-4 



15-7 



-0-3 



64-88 



14-9 



15-0 



-01 



67-08 



13-6 



13-6 



0-0 



69-47 



12-3 



12-3 



o-o* 



73-70 



100 



10-2 



-0-2 



76-55 



8-9 



90 



-0-1 



87-12 



53 



5-4 



-01 



90-02 



4-6 



4-7 



-01 



100-42 



2-5 



2-5 



00 



112-87 



0-8 



0-8 



00 



124-28 



-0-2 



-01 



-01 



135-65 



-0-8 



-0-7 



-01 



148-37 



-1-3 



-1-2 



-01 



158-83 



-1-5 



-1-4 



-o-i 



17207 



-1-7 



-1-6 



-0-1 



183-70 



-1-9 



-1-7 



-0-2 



209-20 



-1-9 



-1-8 



-o-i 



231-73 



-1-7 



-1-9 



4-0-2 



236-28 



-1-8 



-1-9 



+0-1 



240-85 



-1-7 



-1-9 



4-0-2 



In this experiment the calorimeter contained 158*2 grins, 

 of water and about half a c.c. of oik The thermal capacity of 



