ELISHA MITCHELL SCIENTIFIC SOCIETY. 85 



sionally. This was kept up duringf two months of sum- 

 mer weather. The loss in the last fifteen days was 

 about .02 per cent, of the whole. The mass was pow- 

 der3% with a slig-htly discolored crust. It was all sol- 

 uble in water, however, and j^ielded a clear colorless 

 solution. It contained 53.30 per cent of ZrOi. This 

 corresponds ver^' nearly to the formula ZrCL and is 

 altog-ether at variance with the results obtained by Ny- 

 lander and with the assertion made by Hermann, that 

 half of the h3'drochloric acid was lost over sulphuric 

 acid. 



This last experiment showed the possibility of secu- 

 ring- pure zirconium chloride, provided the excess of hy- 

 drochloric acid could be removed. It was thoug-ht that 

 this mig-ht be done by heating- in an atmosphere of hy- 

 drochloric acid. A weig-hed flask was so arranged that 

 it could be kept at a definite temperature while a stream 

 of dry hydrog-en chloride was passing- throug-h it. The 

 temperature rang-ed from 100<^ to 110° C.and the chlo- 

 ride placed in the flask melted, solidifying- agfain after 

 the loss of the water and excess of hydrochloric acid. 

 If the dr^^ing- was done slowl}' enoug-h fine crystals of 

 zirconium chloride were g-otten which lost no further 

 weig-ht on being- kept at 100° C. A more rapid drying- 

 left a hard white mass which was quite hygroscopic. 

 Heating this mass for several days did not cause any 

 diminution in weight, provided the flask was kept full 

 of hydrogen chloride. If the mass was heated even a 

 short time in the absence of h^^drogen chloride then 

 further heating caused a continuous loss of weight even 

 in the presence of a rapid stream of h3'drogen chloride. 

 After this it was impossible to secure a constant 

 weight. 



This method of drving has been tried repeatedly on 

 7 



