72 Scientific Intelliyeuce, ^*c. 



The cubebin appears to be identical with piperin. It melts at 

 20"^ and at 86 begins to boil. — Joum. de Pharm. xx. 403.) 



II. — Westminster Medical Society, March 26, 1836. 



Dr. Addison in the Chair. — Dr. Robkrt D. Thomson exhibited 

 several specimens of vegetable concentrated extracts and infusions, 

 which were prepared by careful attention to the nature of the elements 

 which entered into their composition. At the request of the President, 

 he made a few observations upon the specimens submitted to the 

 inspection of the Society. He remarked, that in regard to extracts, 

 it is an important object to reject all those parts which have no 

 action upon the animal system. For example, in the extract of 

 C07iium, the only constituents which can possess any remedial agency, 

 are extractive or tannic acid (both of which names are applied to 

 substances possessing identical properties), and the oxide of Conein. 

 But tannic acid readily decomposes under particular circumstances, 

 as by exposure to the air, when saturated with moisture, and is then 

 converted into a different substance, ulmbi or ulmic acid, possessing 

 different properties. The principle co7iein, in which the narcotic 

 properties of the cofiium maculatum reside, is a colourless oil, but 

 when exposed to the atmosphere, it is changed into a green resin 

 which imparts its colour to the extract. Hence, a good green colour 

 is a test of the genuine nature of this extract, if proceeding from the 

 proper colouring matter, and hence a spurious extract is too often 

 introduced into apothecaries' shops, which is coloured by means of 

 salts of copper. The specimens of this extract before the Society, 

 possessed the green colour of the oxide of conein in perfection, and 

 after having been kept for two years, was as perfect as when first 

 formed, and not a trace of copper could be detected by appropriate 

 tests. It was double the strength of the common extract of the 

 shops, a dose consisting of two grains and a half. The specimen 

 of extract of hyoscyamns, also exhibited, had been preserved for a 

 similar period, without being in the slightest degree impaired, either 

 in appearance, chemical properties, or narcotic effects. Solubility is a 

 test of the purity of this extract. Its dose is two grains and a half. 

 Dr. Thomson called the attention of the Society to a new prepara- 

 tion, the Jiinate of quinin from the cinchona cordifolia, in which the 

 quinin, instead of being in combination with sulphuric acid, as in the 

 form in which that medicine is usually administered, is retained in 

 union with its native acid, and presented in the same form in which 

 it exists in bark. The aromatic and astringent principles of the bark 

 are also retained in this preparation, so that it actually comprises in 

 a concentrated form all the active principles of the bark. It is pale 

 yellow, quite soluble in water, and in doses of five grains forms a 

 more powerful remedial agent than sulphate of quinin. Dr. T. 

 observed, that in favour of the employment of this remedy, he might 

 state that in the course of his experience in China, he had found 

 bark much more effective in the cure of intermittent fever than sul- 

 phate of quinin, showing that the astringent principles of bark 

 possessed a powerful influence on the human constitution. The grea 



