286 Of Sassaruhrin. 



ammonia, straining, washing the residue with water, and desiccation, 

 a brittle, tasteless resin remains, which is quite insoluble in water, 

 but very soluble in alcohol and hydric ether. 



The addition of this sassaruhrin to concentrated sulphuric acid, 

 produces the crimson color already mentioned as resulting from the 

 presence in that liquid of a minute portion of oil of sassafras. I 

 infer that the color is due to the evolution of sassaruhrin, which has 

 a bassic affinity for the acid, to which it owes its birth. The ethe- 

 real and alcoholic solutions of sassaruhrin are of the color of a dingy 

 white wine, but acquire a deep crimson when mingled with concen- 

 trated sulphuric acid. . 



Sassaruhrin may be produced by the union of the acid and oil, 

 provided it be moderated by refrigeration or dilution with water. 



Without some precaution, the heat produced is sufficient to char 

 the resin more or less. The reddening influence of the oils of cin- 

 namon and cloves is due to the generation of resins analogous to 

 sassaruhrin. 



To those resins the names of cinnarubrin and clovorubrin may be 

 severally assigned. Cinnarubrin may be evolved by adding oil of 

 cinnamon to equal parts of sulphuric acid and water, previously mix- 

 ed and refrigerated, the temperature being subsequently elevated till 

 the mass rises up in a foam ; when the whole should be poured into 

 a solution of pearlash, from which the resin may be extricated by a 

 strainer. It is analogous to sassaruhrin, but it is less efficacious in 

 coloring sulphuric acid, and does not, like the former, impart to the 

 sides of the containing glass a rich red color. Moreover, it appears 

 to be partially insoluble in alcohol, and to retain sulphuric acid after 

 being boiled with an alkaline solution. 



I infer that a new series of resins may be evolved from the essen- 

 tial oils by their reaction with sulphuric acid; which, having a gene- 

 ral analogy to each other, may still have discriminating characteristics, 

 arising from the oils whence they may be derived. 



