474 GEOLOGY AND MINERALOGY. 
IDOCRASE. 
Crystals of Idocrase commonly exhibit a well-developed basal plane. In 
Heuland’s cclebrated “ Catalogue ” twenty-four distinct combinations are described, 
and for the greater part figured, by M. Lévy, in all of which the basal plane is 
present, The only crystals known to us in which this plane is absent, are the 
somewhat complex forms from the Ural, figured by Col. Von Kokscharoff. It may 
not be therefore without interest, to state, that a crystal over half-an-inch in length 
and of the ordinary simple form, but without the basal plane, has lately come into 
our possession, It exhibits simply the two vertical prisms and the fundamental 
octahedron, the latter measuring (by common goniometer, the faces being dull) 
129°30! over the polar edges. The colour of this erystal is olive or brownish- 
green. It was brought from Europe, but we do not know its exact locality. 
Persons interested in these matters, may see the specimen at the University, 
Toronto. 
NEW BLOWPIPE-SUPPORT. 
In the examination of substances by the blowpipe, it is frequently necessary 
to subject the assay-matter to the process technically termed “ rvasting,’ in 
order to free it from sulphur, arsenic, or other volatile ingredients. In this 
operation, charcoal is usually employed as a support; but, as, in travelliag es- 
pecially, itis often desirable to economise the stock of charcoal in the blowpipe 
case, pipe-clay supports, strips of mica, and other substances are sometimes used 
as a substitute. We have employed for some time, and with great success, for 
this purpose, small fragments of Meissen porcelain, broken from damaged crucibles, 
capsules, cése., such as can readily be procured from all importers of chemical 
apparatus. In roasting the assay we rarely require more than a low red heat, but 
these supports may be rendered white hot, if necessary, without flying ; and the 
same fragment may often be used, moreover, more than once. The assay is 
crushed to powder, slightly moistened, and spread upon the surface of the porcelain ; 
and afterwards removed by asmall steel or other spatula. These supports are 
conveniently held by the spring forceps figured and described in Vol. III. of the 
Canadian Journal, page 218. 
PUBLICATIONS RECEIVED. 
On the Alloys of Copper and Zinc. By Franx H. Storer. On the Impurities 
of Commercial Zine, By C. W. Extor, and F. H. Storrr.—These are reprints of 
papers communicated to the American Academy of Arts and Sciences, They 
give much valuable information, and contain numerous analyses of various com- 
pounds of zinc and copper, and of Silesian, Belgian, English, American and other 
spelters. Mr. Storer has obtained many distinctly crystallized samples of brass, 
containing variable proportions of the two metals; and as these specimens present 
the same form (monometric octahedrons,) he looks upon zine as belonging to the 
Regular System. The same view, based however on the examination of merely a 
single specimen, has been adopted by Prof. Gustav Rose. 
EK. J. C. 
