184 Intelligence and Miscellanies. 



ing in that direction with great difficulty, and presenting an 

 uneven and sub-hackly fracture. The external planes of the 

 crystals before being broken, were dull and nearly black, ow- 

 ing to a thin coating of brown oxide of iron ; but fresh cleav- 

 ages presented a fine metallic lustre, and a color between sil- 

 ver white and steel grey. It breaks with the greatest diffi- 

 culty, and small masses often flatten under the blow of the 

 hammer, like pure iron. Its hardness is almost that of ordi- 

 nary steel. Specific gravity, in distilled water at 60° F. 7.337. 

 It is highly magnetic with polarity, so distinct as to take up 

 iron filings. Before the blowpipe it melts. 



Fragments of the size of a pea, brought within the exteri- 

 or flame of the compound blowpipe, emitted a very slight va- 

 pour, in which the well known odour of arsenic was detected ; 

 and immediately on coming within the inner cone of flame, 

 they burnt with intense energy, and with a most brilliant 

 light, throwing out a profusion of scintillations, after the 

 manner of pure iron, or more like a burning watch spring. No 

 odonr of sulphur was perceived in these trials. In order, how- 

 ever, to make myself sure of the absence of sulphur, I resort- 

 ed to the following experiment. A portion of the metal was 

 dissolved in dilute nitric acid : the solution was supersatura- 

 ted with potash and boiled in the alkaline liquor ; the pre- 

 cipitate was separated, and the supernatant fluid neutralized 

 by nitric acid, to which was afterwards added nitrate of lead ; 

 the precipitate was separated, and found to be perfectly so* 

 luble in dilute nitric acid, thus evincing the absence of sul- 

 phate of lead, which must have formed part of the precipi- 

 tate, provided sulphur had existed in the mineral under ex- 

 amination. 



After having examined in the usual modes, for silver, gold 

 and other metals, and not discovering any to be present,* I 

 dissolved fifty grains in nitric acid, with a view to ascertain 

 merely the proportion of iron present. After the solution 

 appeared to be effected, I observed a number of little black 

 flakes floating in the liquid, which resisted the action of the 

 acid. These being separated by the filter, were examined 

 and found to be plumbago, which, under somewhat similar 

 circumstances, though less disguised, and more abundant, 



* After the iron had all been removed from the nitric solution by ammonia, 

 and the fluid boiled, hydro-sulphuret of ammonia gave no cloudiness, thus 

 evincing the absence of nickel. 



