Temperature on the Specific Heat of Aniline, 75 



in the same relative position to the intersection of the 2- and 

 4-cell lines as was found in those cases where a 4-ceJl experi- 

 ment had been performed. 



The null point is of course (see Plate I.) in a very different 

 position from that found when the stirring- rate was 5"00 ; and 

 the close agreement between the results given by these three 

 experiments at the high rate, and experiments 13 to 15 at the 

 same temperature but with a slow rate, is a satisfactory proof 

 of the validity of this method of finding 6^. 



Experiments 8 to 39 call for no special comment. They 

 were all conducted with a stirring-rate of (approximately) 5'00; 

 Nos. 9 to 24 with the same mass of aniline as 6 to 8. From 

 No. 25 upwards the mass of aniline was increased to 569'53 

 grms. 



On plotting the values of the capacity for heat of this mass 

 of aniline and the calorimeter, the spot obtained from experi- 

 ments 25 to 27 appeared in a somewhat abnormal position ; 

 consequently, although I had considered the experimental 

 work as completed, I decided to repeat these experiments, and 

 Nos. 40, 41, and 42 give the result. They agree so closely 

 with the corresponding group as to confirm, the position 

 originally assigned to the curve at that temperature (about 



16°-7C). 



The curves on Plate II. (a) give the capacity for heat of the 

 different masses of aniline together with the calorimeter, at 

 different temperatures. Both of the curves resulting from 

 the larger masses show a marked change between 15° and 

 25° 0. It is worthy of notice that the specific heat as de- 

 duced from these curves shows little or no signs of any similar 

 change, but that it appears very markedly in the water- 

 equivalent curve, and in such a manner as to indicate that it 

 was approaching a minimum. Had I not been able to deter- 

 mine the specific heats by methods independent of the 

 behaviour of the calorimeter, I should have concluded that 

 the temperature coefficient of the specific heat of aniline 

 altered considerably at the lower temperatures. 



This indicates the necessity for extreme caution in similar 

 investigations. 



Table VI. gives a summary of the results, obtained from 

 the values given by the curves in Plate II. (a) . 



