636 [June 18, 



giving off sulphurous acid; it is reprecipitated by water in yellow flocks 

 apparently unaltered. When bromine water is added to a strong 

 aqueous solution of munjistine, a pale-coloured flocculent precipitate 

 is immediately produced ; this, when collected on a filter, washed 

 and dissolved in hot spirit, furnishes minute tufts of crystals, 

 evidently a substitution product. I may remark, in passing, that 

 when alizarine is treated with bromine water in a similar way, it also 

 forms a substitution product crystallizing in needles. I am at present 

 engaged in the examination of both these compounds. 



When munjistine is strongly heated on platinum foil, it readily in- 

 flames and leaves no residue ; when it is carefully heated in a tube, 

 it fuses, and crystallizes again on cooling. It sublimes more readily 

 than either purpurine or alizarine, forming golden scales which con- 

 sist apparently of unaltered munjistine, as they give the characteristic 

 rich crimson coloration with caustic alkalies. Baryta water pro- 

 duces a yellow precipitate with munjistine. Acetate of lead throws 

 down a bright crimson precipitate, both in its aqueous and alcoholic 

 solutions. I expect, from this and the bromine substitution com- 

 pound, very shortly to ascertain the atomic weight of this body ; in 

 the mean time I submit the results of its ultimate analysis. 



I. *314 grm. of munjistine yielded '732 grm. of carbonic acid 

 and *106 grm. of water. 



II. -228 grm. munjistine yielded *535 grm. carbonic acid and 

 0765 grm. water. 



I. II. 



C per cent. 63-6 64-0 

 H 377 373 



O 32-63 32-27 



100-00 100-00 



The munjistine operated upon in each case was prepared at 

 different times; moreover No. 1 was burnt with oxide of copper, 

 No. 2 with chromate of lead. 



Munjistine in some of its properties bears considerable resemblance 

 to Runge's madder-orange, the "rubiacine" of Dr. Schurick : it is, 

 however, essentially different from rubiacine, both in several of its 

 properties, such as its solubility in water and alcohol, &c., and in the 

 amount of its carbon rubiaciue, according to Dr. Schunck's analysis, 



