228 Scientific Intelligence. [Sept. 



tail, not being able to follow the comet, would be always left 

 behind, and we should not see the tail after the perihelion 

 precede the comet, as is always the case. 



III. Biographical Notice of Dr . Wistar, of Philadelphia.* 



Dr. Caspar Wistar was born at Philadelphia in the year 1 760 ; 

 his parents were of German extraction, and belonged to the 

 society of friends. He received the first part of his education 

 at the grammar school of his native city ; he commenced 

 his medical studies under the superintendance of Dr. Redman, 

 and he likewise attended the lectures of Drs. Morgan, Shippen, 

 Rush, and Kuhn. In the year 1783 he came over to this 

 country, in order to pursue his studies in the University of 

 Edinburgh ; in 1786 he graduated there, and in the following 

 year returned to his native city, where he settled for the 

 remainder of his life. 



There appears, at this period, to have been two rival medical 

 schools in Philadelphia, one attached to the University, and 

 the other denominated the College ; he was invited to the 

 Professorship of Chemistry and Physiology in the latter of these 

 institutions, which he accepted. After some time, however, 

 these two rival establishments were united in the University of 

 Pennsylvania, of which Dr. Wistar was made joint professor 

 of Anatomy and Surgery with Dr. Shippen. In this situation he 

 continued until his death, and appears to have been completely 

 occupied with the duties of this office, in conjunction with those 

 of medical practice. All his publications seem to have been of 

 a professional nature, and to have been chiefly confined to 

 papers in the American periodical works. His principal literary 

 distinction he obtained only a short time before his death. His 

 biographer informs us, " that when the presidency of the 

 American Philosophical Society for promoting useful Knowledge 

 was vacated in 1816, Dr. Wistar, by an unanimous suffrage, 

 was elected to fill that honourable station : honourable, as having 

 been previously occupied only by his illustrious predecessors, a 

 Franklin, a Rittenhouse, and a Jefferson." 



IV. Experiments on Metallic Alloys obtained by Means of Gal- 

 vanism. By Prof. Brugnatelli.t 



If we plunge a plate of zinc into a dilute solution of the nitrate 

 of silver, the silver attaches itself to the zinc ; two electric poles 

 are then established, by which the water is decomposed. The 

 oxygen which is attracted to the positive zinc pole oxidates it, 

 and the hydrogen which is attracted to the negative silver pole 

 serves to oxidate the metal which has been dissolved. But the 



♦ Abstracted from a tribute to the memory of the late C. Wistar, M.D. &c. b/ 

 his friend Dr. Hossack. 



i From Journ. Pharm. iii. 425. (Sept. 1817.) 



