OBITUARY NOTICES. Xlll 



studied and its products were analyzed. This paper covers forty- 

 eight pages and is substantially his inaugural dissertation at Mar- 

 burg. The immediate occasion of this investigation was the send- 

 ing to Prof. Bunsen for analysis of various samples of refined 

 copper from Sweden and Norway, together with two samples from 

 the Riechelsdorf works ; the whole coming from the Kurfurstliche 

 Ober-berg und Salzwerke-Direction of Cassel. The examination of 

 these coppers was turned over to Dr. Genth, and his paper is 

 divided into six sections. The first describes the processes in use 

 at Riechelsdorf, the second gives the analytical methods used, the 

 third considers the products examined with their physical proper- 

 ties and chemical composition, the fourth gives the analysis of other 

 coppers for comparison, the fifth the same in tabular form and the 

 sixth states some chemico-technological conclusions. The value of 

 this research was recognized by a letter of thanks from the Direc- 

 tion. It resulted in some material changes in the processes 

 employed at the Friedrichs works. 



In December, 1852, Dr. Genth read before the Academy of Nat- 

 ural Sciences a paper on a supposed new element which he had de- 

 tected in certain small white grains associated with iridosmine and 

 platinum from California. On treatment with hydrochloric acid, 

 two of the metallic particles were observed to evolve hydrogen. On 

 removing them from the liquid, they were seen under a magnifier to 

 be mixed with gold. In color they were between tin white and steel, 

 were malleable, but harder than tin and were soluble in nitric acid, 

 yielding a crystalline salt. With hydrogen sulphide the solution 

 gave a brown precipitate. Before the blowpipe on charcoal the 

 metal fused readily, but soon became covered with a black oxide. 

 It gave no incrustation. With borax in the outer flame it dissolved, 

 giving a colorless bead which became opalescent on cooling. 

 Though resembling tin, the new metal is distinguished from it by 

 its complete solubility in nitric acid, by the brown precipitate 

 with hydrogen sulphide and by.the absence of a white incrustation 

 before the blowpipe. 



The chemical investigation, however, by which Dr. Genth is 

 most widely known is undoubtedly that made on the ammonia- 

 cobalt bases. His original memoir on this subject was published in 

 Philadelphia in 185 1 in Keller and Tiedemanri s " Nordamerikan- 

 ischer Monatsbericht filr Natur und Heilkunde" under the title 

 "Vorliiufige Notiz iiber Gepaarte Kobalt-Verbindungen." This 



