1915] Th, Lissizin 21 



täte, dissolves slightly in dilute alcohol, and is almost insoluble in 

 95 percent alcohol. I have used the following method, based on 

 these properties, f or the Isolation of this substance : 70 gm. of hair 

 were digested with 5-6 1. of 2 percent potassium permanganate sol. 

 and allowed to stand for several days. The clear fluid was filtered, 

 acidified with hydrochloric acid, and the precipitate separated by 

 filtration. The filtrate was made slightly alkalin with dilute soda 

 sol., and precipitated with lead acetate. The precipitate was washed, 

 first by decantation and then on a filter, suspended in water, and 

 treated with hydrogen sulfid. Precipitated lead sulfid was removed 

 by filtration, the filtrate evaporated to a syrupy consistence, and 

 extracted several times with 95 per cent alcohol. The residue was 

 dissolved in a small amount of water, and the Solution yielded a pre- 

 cipitate with a large excess of alcohol. This precipitate was dis- 

 solved in a little water and re-precipitated with alcohol. The final 

 product contained 12.5 percent of ash and 8.81 percent of sulfur. 

 In Order to purify the product it was re-dissolved several times in 

 water, re-precipitated with alcohol, and washed with alcohol and 

 ether. This purified material was dried at 110° and analyzed 

 (IX-XVI). 



IX, 0.1437 gm. gave, after ignition, 0.0089 gm. of ash, which 

 consisted of silicic acid, with traces of potassium, sodium, calcium, 

 iron and manganese. 



X. 0.0743 gm. gave, after ignition, 0.0046 gm. of ash. 



XL 0.1881 gm. gave, after burning with lead Chromate, 0.2537 

 gm. of carbon dioxid and 0.0928 gm. of water. 



XII. 0.1808 gm. burnt with lead Chromate, yielded 0.2385 gm. 

 of carbon dioxid and 0.0908 gm. of water. 



XIII. 0.2166 gm. gave 26.3 c.c. of nitrogen, at 23.5° and 763 

 mm. Hg. 



XIV. 0.1762 gm. gave 21.1 c.c. of nitrogen, at 22.5° and 762 

 mm. Hg. 



XV. 0.1578 gm. gave, on fusion by the method described above 

 (determination I), 0.1121 gm. of barium sulfate. 



XVI. 0.1787 gm. gave 0.1247 gm. barium sulfate. 



