THE 



LONDON AND EDINBURGH 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



♦ ' 



[THIRD SERIES.] 



APRIL 1838. 



XL VI. On the Action of Nitric Acid upon Bismuth and other 

 Metals. By Thomas Andrews, M.D.y Professor of Che^ 

 mistry in the Royal Belfast Institution. 



To the Editors of the Philosophical Magazifie and Journal, 

 Gentlemen, 

 T AM happy to find that the observations which I commu- 

 ^ nicated to the British Association, on some singidar modifi- 

 cations of the ordinary action of nitric acid upon certain metals, 

 have attracted the attention of so distinguished a philosopher 

 as M. Schcenbein, whose opinions upon this subject must be 

 considered to be of peculiar value. As, however, the results 

 of some of my experiments are at variance with those which 

 M. Schcenbein has obtained, and would tend perhaps to mo- 

 dify his conclusions, and as the published notice of my paper 

 is very brief and imperfect, I shall now endeavour to give as 

 complete an account of this subject as my investigations will 

 enable me to do. 



In the following extract from the manuscript read at Liver- 

 pool will be found a complete description of the phseno- 

 mena to which M. Schcenbein alludes, and which he supposes 

 that I may not perhaps have remarked. 



" Having introduced a small fragment of bismuth into a 

 large excess of nitric acid of sp. gr. 1'4?, and afterwards 

 brought a plate of platina exposing an extensive surface to the 

 liquid, into contact with the bismuth, the solution of the latter 

 almost entirely ceased, while at the same time its surface as- 

 sumed a peculiarly brilliant lustre. On removing the platina, 

 the bismuth sometimes began to dissolve in its ordinary man- 

 ner ; at other times, a dark film appeared upon its surface, 



PhiL Mag. S. 3. Vol. 12. No. 75. April 1838. 2 G 



