1826.] Scientifie Notices^Miscellanemis, 237^ 



The best method of obtaining molybdaena in some quan- 

 tity is, to heat the molybdic acid in a porcelain tube. Whea 

 this tube is heated to redness, there is introduced into it a 

 current of hydrogen gas, which is continued as long as it pro- 

 duces water. — (Edin. Journ. Science.) 



Miscellaneous. 

 3. 0)1 Native Silver' from Michigan. By H. R. Schoolcraft. 



Mineralogical and Chemical Characters. — By examining this 

 mineral, it will be perceived to possess the colour, lustre, mal- 

 leability, and other obvious characters of native silver. It is so 

 soft, as to be easily cut by the knife ; and in a state of purity 

 which permits it to spread under the hammer. These characters 

 serve to distinguish it from antimonial silver, which is not 

 malleable ; from native antimony, which tarnishes on exposure, 

 &c. The metal occurs in thin massive veins in the rock. These 

 veins sometimes intersect, but never cross each other. It is 

 also disseminated in small particles through the stone, or spread 

 in flattened masses over its surface. Some of these masses were 

 detached by the discoverer, but have been preserved, and are 

 presented to the Lyceum with the more solid and undisturbed 

 portions. 



By submitting a small portion of the metal to the action of 

 nitric acid, I obtained an imperfect solution. On repeating the 

 experiment, and adding a little sulphuric acid, the action was 

 more brisk, and a clear and apparently perfect solution effected. 

 By standing, however, a pulpy white precipitate appeared at 

 the bottom of the glass. This was collected, and submitted to 

 the action of the blowpipe, on a basis of charcoal. The result 

 gave a number of minute, metallic globules, possessing greater 

 lustre, malleability, and ductility, than the original mass. I 

 repeated the latter experiment, adding to the nitro-sulphuric 

 solution muriate of soda. A more perfect precipitation of the 

 white powder was effected ; but the results with the blowpipe 

 remained the same. 



Geognostic Position. — It is a rolled mass. An opinion of the 

 specific character of the rock may be dubious, from the smallness 

 of the specimen. It appears to have been detached from a 

 stratum of gneiss, and is essentially composed of quartz. The 

 blackish colour of some parts of this latter mineral would, at a 

 first glance, lead us to attribute this colour to the presence of 

 hornblende ; but on a closer examination, it will be perceived to 

 be owing to a dark coloured steatite, which, in certain parts of 

 the rock, is well developed, soft, and easily cut. A little calcspar 

 is intermingled with the steatite. 



Locality. — I am indebted to the politeness of Lieut. Lewis S. 

 Johnston, of the British Indian Department, at Maiden, (U. C.) 



