444 THE POPULAR SCIENCE MONTHLY, 



these, a variety found near Gouverneur, in the State of New York, is 

 distinguished by its peculiar brown color and internal structure. 

 There is a suite of at least one hundred specimens of this variety 

 alone, each one having been selected on account of some characteristic 

 difference, and presenting together all the known and probably some 

 yet unclescribed crystalline faces. Some of the specimens are aggre- 

 gates of crystals, one mass displaying fifty distinct terminations ; 

 others are individual crystals, frequently doubly terminated and show- 

 ing the different arrangement of the planes upon the analogous and 

 antilogous poles. The dimensions of one of these single crystals, 

 reputed to be the largest ever found at Gouverneur, deserve a perma- 

 nent record. It is four inches in height and four and a half inches 

 through, with the rhombohedral faces of one termination almost per- 

 fectly developed, and with one rhombohedral face of the other termi- 

 nation four inches in width, the two other corresponding planes hav- 

 ing been points of attachment to the rock. It is bounded by eighteen 

 prismatic faces, all of which are perfect in form and polish. 



Of the black tourmalines, there is one from Springfield, New Hamp- 

 shire, which has a termination remarkable for the extreme development 

 of the basal plane. It is 4^ x 3f inches across, and almost extinguishes 

 the primary rhombohedron. Among entirely unique specimens from 

 Greenland, Bovey Tracey, in Devonshire, England, Haddam, Connect- 

 icut, Norway and Sweden, we might mention a group from Green- 

 land, of fifty or sixty crystals, mostly doubly terminated, and from 

 four to six inches in length, forming a rosette with divergent crys- 

 tals. 



To the finely colored red tourmalines, which are frequently cut and 

 polished as gems, the name of rubellite is given ; those from Siberia be- 

 ing mostly violet red, the Brazilian rose-red ; the specimens from Ches- 

 terfield and Goshen, Massachusetts, are pale rose-red and opaque; those 

 from Paris, Maine, fine ruby-red. Among these rubellites there are 

 six from Elba, of exquisitely delicate pink-color. They are hexagonal 

 prisms, one of which is one and a quarter inch in height and three 

 quarters of an inch in diameter, all implanted on a base that is itself 

 very beautiful from the contrasted groups of rock-crystal, adular, and 

 rosettes of mica, of which it is made up. Of rubellites from Elba 

 there are more than fifty specimens, some of them reposing upon the 

 native rock ; others are terminated detached crystals of various shades 

 of pink — also crystals on the gangue and fine detached rubellites from 

 Siberia. When it is remembered that the slightest imperfection in 

 the sharpness of an edge or angle, the scratching of a single face, ex- 

 cludes a specimen from this cabinet, and that none are admitted which 

 are not at the same time remarkable for size, beauty, and perfection of 

 crystalline form, the brilliant effect of a drawer filled with these natu- 

 ral gems can be imagined. 



More than usual interest attaches to the mineral of which I am 



