266 



the kunzite of Mddujdscar, and we tried to find in the described 

 way the lowest temperature, at vvhieii a just discernible trausfbrin- 

 atiou of ('. -^^ {i-ïv)vm yet occurred. The reader may be put in mind, 

 that the experiments 1—14 were made with a thermoelement, 

 provided with a very thin protecting tube ; in the experiment 14 — 20, 

 this protecting tube was omitted, which appeared however to make 

 no appreciable difference. 



In this case therefore an evident transformation has already taken 

 place at 9170 M. V. (iincorr.), or at 9198 M. V. = 968°C. (G. Th.). 



