634 [June 18, 



no alizarine at all, but purpurine and a beautiful orange colouring 

 matter crystallizing in golden scales, to which I purpose giving the 

 name of " munjistine." Munjistine exists in munjeet in considerable 

 quantity, and can therefore be easily obtained. 



The colouring matter of munjeet may be extracted in various ways ; 

 that which I have found most suitable is as follows : each pound of 

 munjeet in fine powder is boiled for four or five hours with two pounds 

 of sulphate of alumina and about sixteen of water. The whole of the 

 colouring matter is not extracted by a single treatment with sulphate of 

 alumina ; the operation must be repeated therefore two or three times. 

 The red liquid thus obtained is strained through cloth filters while 

 still very hot, and the clear liquor acidulated with hydrochloric acid. 

 It soon begins to deposit a bright red precipitate, the quantity of 

 which increases on standing, which it should be allowed to do for 

 about twelve hours. This precipitate is collected on cloth filters and 

 washed with cold water till the greater portion of the acid is removed. 

 It is then dried, reduced to fine powder, and digested in a suitable 

 extracting apparatus with boiling bisulphide of carbon, which dissolves 

 out the crystallizable colouring principles of the munjeet, and leaves 

 a considerable quantity of dark-coloured resinous matter. The excess 

 of the bisulphide of carbon having been removed by distillation, the 

 bright red extract, consisting chiefly of a mixture of munjistine and 

 purpurine, is treated repeatedly with moderate quantities of boiling 

 water and filtered. The munjistine dissolves, forming a clear yellow 

 liquid, while almost the whole of the purpurine remains on the filter. 

 When this solution is acidulated with hydrochloric or sulphuric acid, 

 the munjistine precipitates in large yellow flocks. These are col- 

 lected on a filter and washed slightly with cold water. The precipi- 

 tate is then dried by pressure, and dissolved in boiling spirit of wine 

 slightly acidulated with hydrochloric acid to remove any adhering alu- 

 mina. As the munjistine does not subside from cold alcoholic solutions, 

 even when they are largely diluted with water, about three-fourths of 

 the spirit are drawn off by distillation, when the munjistine is deposited 

 in large yellow scales. By two or three crystallizations out of spirit 

 in the way just described the munjistine is rendered perfectly pure. 



I have likewise succeeded in extracting munjistine directly from 

 munjeet by boiling it with water, filtering the solution, which has a 

 dark brownish-red colour, and then acidulating with hydrochloric 



