DETERMINATION OF THE THERMAL CONDUCTIVITY OF MARBLE. 281 



is very much like the one obtained by me. We may therefore assume 

 that the value A' = .0073 is not very far removed from the true value 

 of the thermal conductivity of white coarse-grained marble. 



The present mode of experimenting seems to be open to criticism 

 in one respect only — namely, the method of determining the tempe- 

 rature at the centre. With a distinct improvement in this particular, 

 the accuracy of the final result would be greatly enhanced. It is 

 hoped that such improved experiments may be undertaken at some 

 future time. 



The experiments here described were all performed by Messrs. 

 K. Ikeda and M. Ogawa, chemical students, while working in the 

 Physical Laboratory, under my direction. 



