‘ 
F. A, Genth’s Contributions to Mineralogy. 191 
with a mixture of dilute chlorhydric and tartaric acids. The so- 
lution thus obtained, contained ‘no antimony, but lime, magnesia, 
ferrous oxyd and arsenious acid, corresponding with : 
Carbonate of lime, - - - - - 8648 p. ¢. 
“ “ magnesia, - elige fs 2°05 89°43 
“ “« iron, es rs pie O°6 
Arsenious acid, - - 10°80. 10°80 
100°23 
The residue dissolved in a mixture of chlorhydric acid and 
chlorate of potassa, left behind some quartz, which was filtered 
off and the arsenic separated from the antimony by Leyol’s 
method; the following results were obtained : ee 
Matte 2 Se. ee p.c. 
tetas, te i SE ee es ee > 80°81 
Antimony, é . ‘ ee ee ee 
Of the lsomorphous metals ,', is antimony. After deducting 
the quartz the composition is : > 
Found. alacedl 
Arsenic, =~ - 9082 4 nic, - - 90°81 
Antimony, - - 918 zs Antimony,- - 919 
Itresembles in its composition the antimonial arsenic from the 
P almbaum Mine near Marienberg, Saxony, analyzed by Schultz, 
Sontaining 92-03 per cent of arsenic and 7:97 per cent of anti- 
tony. (Rammelsberg’s Mineralchemie, p. 984.)  * 
3. Arsenids of Copper. . 
_ % Whitneyite.*—A fter the publication of the results of my ex- 
amination of the peculiar dead of copper from Lake Superior, 
Introducing whitneyite as a new species (this Journal, [2], XXxvii, 
400), T learned of the existence of several specimens of arsenids of 
Copper from Lake Superior, and that some fea i examina- 
tions had been made of one of them by Dr. John Torrey even as 
hay a 1853, which, however, have never been published. I 
3 
minerals, whitneyite and algodonite, and although it was almost 
™pPossible to a slein ante in a state of absolute purity, the _ 
Itis ising that after Prof. George J. Brush (9th sup to Dana's Min- 
Wag Pe tila Jonntst [2], xxi, 370,) has sciiend the oversight of D. Forbes (Phil. | 
two 4] xx, 423) giving the new name “ Darwinite,” to a pee Tt 
x, Fog Previously, this name is still continued by F. Field—(Philos, Mag., [ 
+ 
e 
