Geology and Natural History. 485 
which appear on the fragment. nother fragment, weighing 
two and a half ounces, is perfectly limpid and coloriess. The 
1 weighs four ounces. It is of a light 
straw color and is perfectly clear, having no flaw in it. The 
passing probably into 4-2), 4-2, and 3-7. 
9. Jeremejefite and Hichwaldite-—The chemical characters of 
saad 478). The crystalline form of the species has since been 
escribed b ebsky. An optical examination as con- 
rmed the observation of Jeremejef, made in 1869 upon the sam 
crystals, which were then supposed t beryl, viz: that only the 
the crystals. study of the crystalline form has convinced 
same chemical substance is known to appear in both the hexagonal 
and orthorhombic (or monoclinic) forms ; the observations of Pro- 
fessor Cooke on the iodides of antimony are to the point.— Ber. 
_ Ak, Berlin, June 14,.1883. 
