12 PROCEEDINGS OF THE ACADEMY OP [1S79. 



NOTE ON HYRACETJM. 

 BY WM. H. GREENE, M.D., AND A. J. PARKER, M.D. 



Among the native remedies from the Cape of Good Hope, ex- 

 hibited at the Centennial Exhibition, was a peculiar substance 

 called hyraeeum, which was supposed to be the inspissated urine 

 of the Cape Hyrax {Hyrax capensis). 



The material was obtained from Dr. Leidy, who, in the Pro- 

 ceedings of the Acadeni}-, December, 1816, p. 325, gave a short 

 account of it. According to this account, " the Hyrax is reputed 

 to inhabit gregariously rocky places at the Cape of Good Hope, 

 and the accumulated urine in the hollows of rocks, gradually 

 evaporating, is supposed to give rise to the product in question. 

 It is reported as having been employed in medicine with the same 

 effect as castoreum." 



Prof. Cope remarked that "a material resembling the concre- 

 tion made by the urine of the Hyrax was found in the fissure's of 

 the rocks of New Mexico. It is probably the fecal and renal 

 deposit of the wild rat, Neotoma." 



About two years ago, we made an exhaustive examination of 

 this substance. It is a dark-brown, brittle, and resinous material, 

 having an aromatic odor, and a bitter taste. About 56 per cent, 

 of it is soluble in water, and nearly one-third of the residue from 

 the aqueous extraction is soluble in alcohol, ether, and chloroform. 



The soluble material amounts in all to about 70 per cent., and 

 the remainder is composed of 14 per cent, of woody fibre and 

 insoluble organic material, and 16 per cent, of sand and other 

 inorganic substances. 



On ignition, hyraeeum yields about 34 per cent, of ash, which 

 is composed of chlorides, sulphates, phosphates, and carbonates 

 of the alkaline metals, and of lime and magnesia. It also contains 

 nitrates in small proportion. 



On precipitating the organic material contained in the aqueous 

 extract with lead acetate, and afterwards decomposing the sus- 

 pended precipitate by means of sulphuric acid, a substance was 

 obtained which constitutes the greater portion of the organic 

 material soluble in water. It was hard, horny, and of a resinous 

 character, transparent, and of a bright brown tint. It probably 

 consists of several substances, but we were unable to obtain a 



