Mr. Newman on the Mountain Barometer. 279 



face of the mercury, and the point given at which it was marked 

 off; when with the correction for the capacities of the tube and cis- 

 tern, and also the temperature, the actual height of the barometer 

 is ascertained. Upon examining the first four which I made inde- 

 pendent of each other on this principle, one for Mr. Daniel], one 

 for the Royal Society, and two for Captain Sabine, they agreed 

 within .004 of an inch with each other. 



Art. XIII. Observations on the Ultimate Analysis of certain 

 Vegetable Salifiable Bases. By W. T. Brande, Esq., 

 Sec. R.S., and Professor of Chemistry in the Royal 

 Institution. 



Since the discovery of a peculiar crystallizable substance, pos- 

 sessed of alkaline properties, in opium, by M. Sertuerner, in the 

 year 1816, a variety of analogous salifiable bases have been de- 

 tected in, and separated from, other vegetable products. Among 

 these none are more remarkable than the two substances dis- 

 covered in certain species of the genus Cinchona by Messrs. Pel- 

 letier and Caventou, in the year 1818. To that separable from 

 the common pale Peruvian bark, (Cinchona Lancifolia,) they have 

 given the name of Cinchonin ; and of Quinine, to that obtained 

 from the yellow bark, (Cinchona Cordifolia.) They have also 

 ascertained that the red bark contains no distinct principle, but 

 that it derives its virtues from a mixture of those existing in the 

 two varieties just named. In conformity with the principles of 

 chemical nomenclature adopted in this country, the former may 

 be called Cinchonia and the latter Quinia. 



The essential medical virtues of opium, cinchona, and of the 

 other substances in which they have been found, appeal - , in all 

 cases, to depend upon these newly-discovered bodies, and in this 

 respect they promise to form very important articles in the l\Ia- 

 tcria Mcdica ; and they arc particularly interesting to the chemist, 

 as constituting a distinct class of salifiable bases, possessed of 



