OF AETS AND SCIENCES. 7 



melting-point. It is insoluble in water, soluble with decomposition in 

 alcohol and iu glacial acetic acid, which acts upon it, however, less 

 rapidly than the alcohol, very slightly soluble in ether, chloroform, 

 and carbonic disulphide, insoluble in ligroine and benzol. Its be- 

 havior with various reagents was taken up, but no results were 

 obtained which promised to repay further study. The following 

 observations, however, are of some interest. Potassic hydrate and 

 also argentic oxide convert it in part into vanillin, to judge from the 

 smell, while both anilin and zinc cleaned with sulphuric acid act upon 

 it, the former with considerable evolution of heat, — thus confirming 

 the inference that it is an addition-product. The principal products 

 from these reactions, as well as those from the action of sodic carbon- 

 ate and water, and of reducing-agents, are ill-defined bodies which 

 we could find no means of purifying. 



Pentabromcurcumindibromide, Cj^HgBr^O^. If curcumin in glacial 

 acetic acid is treated with an excess of bromine, or the solid tetra- 

 bromide treated with bromine, a red substance is formed, which, after 

 washing with water and drying in vacuo, gave the following results : — 



0.2898 g. of substance gave 0.2230 g. of CO^ and 0.0304 g. of Hp, 

 0.2G66 g. of substance gave according to Carius 0.9323 g. of AgBr. 



Calculated for Ci4H9Br704. Found. 



Carbon 20.97 20.98 



Hydrogen 1.12 1.16 



Bromine 69.91 69.02 



Properties. A red amorphous substance melting near 120°, but 

 without definite melting-point ; insoluble in water, soluble in alcohol 

 apparently with decomposition, easily soluble in ether and glacial 

 acetic acid, leaving a varnish, slightly soluble in benzol, insoluble in 

 ligroine. Strong sulphuric acid acts on it very slowly, finally turning 

 it a more brilliant red. Our study of the behavior of this substance 

 has led to no more definite results than in the case of the tetra- 

 bromide. 



Heated alone, it gives off bromine and hydrobromic acid, leaving a 

 black tar, from which a yellow substance containing bromine can be 

 extracted by alcohol ; we may study this experiment more carefully 

 hereafter. Sodic hydrate, sodic carbonate and water, sodic alcohol- 

 ate, and argentic oxide all act upon it, but no smell of vanillin was 

 observed in any case. The same is true of several oxidation experi- 

 ments we have tried upon it, and this would seem to indicate the 

 presence of a portion of the bromine in the benzol ring. It is an 



