300 PROCEEDINGS OP THE AMERICAN ACADEMY 



freed from tin with sulphuretted hydrogen ; upon concentrating the 

 filtrate, long needles separated, which varied in color from brown to 

 nearly white. By further concentration of the mother liquors a fresh 

 crop of crystals was obtained, and the precipitate of sulphide of tin 

 must be boiled out several times with water, as the reduction-product 

 is but slightly soluble. As the substance seemed to be decomposed to 

 a certain extent by our attempts to purify it by crystallization, we 

 analyzed some of it without further purification, while other samples 

 were crystallized once more from hot water, allowing the solution to 

 cool in vacuo to avoid oxidation by the air. It was dried in vacuo, 

 and analyzed with the following results : — 



I. 0.0977 gr. of the substance gave on combustion 0.1224 gr. of car- 

 bonic dioxide and 0.0434 gr. of water. 

 II. 0.3108 gr. gave on combustion 0.3869 gr. of carbonic dioxide ami 

 0.1128 gr. of water. 



III. 0.1113 gr. of the substance gave 9.8 c.c. of nitrogen at a temper- 



ature of 25°. 5 and a pressure of 763 mm. 



IV. 0.1010 gr. of the substance treated with argentic nitrate and the 



precipitate washed with nitric acid and water gave 0.0498 gr. 

 of argentic chloride. 

 V. 0.4762 gr. gave 0.2461 gr. of argentic chloride. 



Found. 

 I. II. III. IV. V. 



Carbon 34.17 33.93 



Hydrogen 4.93 4.03 



"Nitrogen 9.84 



Chlorine 12.19 12.77 



The free base corresponding to this chloride was next prepared by 

 adding amnionic hydrate to a strong solution of it, when a white 

 precipitate swimming in a dark green liquid was obtained. It was 

 purified by washing with cold water, in wdiich it is as good as insolu- 

 ble, until the wash water gave no test for a chloride, then dried in 

 vacuo, and analyzed with the following results : — 



I. 0.1690 gr. of the substance gave on combustion 0.2587 gr. of 

 carbonic dioxide and 0.0580 gr. of water. 

 II. 0.2021 gr. of the substance gave 23.7 c.c. of nitrogen at a tem- 

 perature of 24°. 5 and a pressure of 768.5 mm. 



Found. 

 I. II. 



Carbon 41.75 



Hydrogen 3.81 



Nitrogen 13.28 



