84 JOURNAL OF THE 



the excess of the acid. There was no attempt at dry- 

 ing this between filter paper. The method of prepar- 

 ing- this salt has been fully described in a previous pa- 

 per in \)i\^ Journal of Aiialytical and Applied Qliemis- 

 Iry, 5, 551. 



In the first experiment this chloride was washed once 

 with water and then put in a dessicator and dried over 

 calcium chloride (porous dessicated). It remained in 

 the dessicator about seven months. Kven after this 

 lapse of time it still continued to show a slight loss in 

 weight. It yielded, on analysis, 48.84 per cent. TaxO^. 



Another portion was placed in a jar over solid lumps 

 of sodium hydroxide. After six weeks the loss was 

 very slight. Careful ignition left a residue of Zr02, 

 equivalent to 42/)9 per cent, of the original weight. 

 There was found to be 24.44 per cent, of chlorine 

 present. 



Again a portion was placed over calcium chloride and 

 dry air was drawn over it at the rate of about fifty 

 litres in the twenty-four hours for six months. After 

 the first two months it was examined weekly by the 

 interposition of a flask containing silver nitrate to see 

 whether hydrochloric acid was still coming off. Kven 

 after the lapse of so long a time as this it was found 

 that the loss of hydrochloric acid continued, although 

 it was slight. On analysis this gave TaxO^ 42.28 per 

 cent, and CI. 24.35. Although the results in this, and 

 the experiments immediately preceding, correspond fair- 

 ly well they are unsatisfactory, as they point either to a 

 mixture of chlorides or an oxychloride of very compli- 

 cated formula, and hence unsuited for the ultimate aim 

 of the research. 



Lastly a portion was placed over concentrated sul- 

 phuric acid and the atmosphere above it exhausted occa- 



