Analysis of a Magnetic Iron Pyrites. 219 
The Cherocampa tersa, an elegant miller, was taken in our 
garden, in the month of May last. Dr. Harris describes it asa 
native of South Carolina, where it feeds on a species of plant 
which does not grow at the North.* The food it finds as a sub- 
Stitute, has not been ascertained. Pos 
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Arr. XIX.—Analysis of a Magnetic Iron Pyrites, containing 
Nickel, from Gap Mine, Lancaster Co., Pennsylvania ; by 
M. H. Bore, Professor of Chemistry and Natural Philosophy, 
Central High School, Philadelphia. ; 
Descriprion.—Color, dark gray drawing into bronze; lustre 
metallic ; texture, granular interspersed in some places with co 
per pyrites, hornblende and black mica. Powder dark greenish ; 
Streak black. Attracted by the-magnet, and possessing distinct 
Magnetic polarity. Specific gravity of the whole piec#(inclu- 
ong interspersed gangue,) 4:193. Somewhat porcus and easily 
roken. : 
_ % The filtered solution from the silica ($1) was precipitated 
in cold by carbonate of lime (whiting) previously triturated wit 
Water, till after standing for twenty-four hours it showed still a 
film of fine undecomposed carbonate of lime floating on the top of - 
it. The precipitate was then separated by filtration and washe 
moderately with water. The filtered solution, after being acidu- 
lated, yielded no precipitate by sulphohydric acid. 
_ 3. By the addition of ammonia in slight excess to the above, 
it yielded a black precipitate of sulphuret of nickel. The pas- 
Sage of sulphohydric acid was then continued through it for 
Some time, by which the sulphuret of nickel settled to the bot- 
tom, and the supernatant solution became clear, and of a light 
yellow color, indicating no nickel in solution. The sulphuret of 
nickel was then Risorod and washed ; the filtered solution being 
Tejected for further use. 2 
he precipitate obtained by carbonate of lime (¢ 2) was re 
dissolved in chlorohydric acid, filtered from the separated silica - 
na 
. 
