298 ANNUAL OF SCIENTIFIC DISCOVERY. 



mixed with the gold, in minute scales and grains. Associated with it 

 there was another metal which resisted completely the action of the 

 acid. It formed small plates of a tin-white, generally hexagonal, and 

 so hard as to resist steel ; these characters show it to be iridosmine, 

 the native alloy of the rare metals iridium and osmium, which is 

 found with the gold of South America, and is from its extreme hard- 

 ness, employed to form the points of gold pens. Report Canadian 

 Geologists. 



LARGE DEPOSITS OF GRAPHITE. 



AT St. Johns, N. B., near the new suspension bridge over the St. 

 John's river, a very extensive deposite of graphite has been opened 

 and explored to a considerable extent. The vein, or bed as it might 

 more properly be called, is nearly vertical, and inclosed between beds 

 of highly metamorphic schists. It is entered near the water on the 

 face of a precipitate cliff about seventy feet high, the walls of the 

 lode being in the main parallel to the graphite deposite. This bed has 

 been explored by a gallery or adit level over a hundred feet, and by 

 cross cuts at right angles to this some twenty or more feet. All these 

 are in the graphite mass, and of course the floor and roof of the 

 levels are of the same mineral. The quartzose walls have occa- 

 sionally approached, and in some cases masses of quartz, or schist, 

 have been included in the graphite. The course of this deposite is 

 about northeast and southwest, or nearly injhe direction of the strike 

 of the strata of schist. The graphite is nof of a very superior quality 

 as a mass, though portions of it are quite pure. As yet no solid and 

 perfectly homogenous masses have been taken out. It has a foliated 

 structure more or less highly marked. Iron pyrites is too abundantly 

 diffused in it to admit of its use for crucibles. The chief economical 

 use made of it has been in facing the sand moulds for iron castings, 

 for which purpose it is ground to a fine powder. Some of the finer 

 parts are also used to manufacture pencils. Many hundred tons of 

 graphite from this deposite have already been taken out since the 

 mine was opened two years ago, and the supply may be esteemed 

 inexhaustible. The vein or bed re-appears on the opposite side of the 

 St. John's river, and on the side now opened it has been traced over 

 a mile. The position of the deposite in conformable metamorphic 

 schists, suggests the conjecture that this deposite of graphite may 

 represent a former coal bed. 



LAKE SUPERIOR COPPER MINES. 



THE National Intelligencer publishes a few facts to show the advan- 

 tage of a judicious prosecution of the copper mining business. The 

 Intelligencer says : 



The mine which has thus far been the most productive is called the 

 Boston and Pittsburg Mining Company. Work was commenced in 

 1848. A capital of 8110,000 was paid in, or about $18 50 per share on 



