1890.] Mineralogy and Petrography. 1195 
stibnite, manufactured bismuth oxide and bismuthinite. The following 
groups are also thought to be isomorphous, since they occur in iso- 
morphous compounds: CdO and CdS, MnO and MnS, and FeO and 
FeS. Mr. Dudley * describes pseudomorphs of vivianite after roots 
of coniferous plants, from the clay banks of the Cumberland River, 
ten miles above Eddyville, Ky. In a short note Wulff 5 suggests a 
method by which plane angles may be measured under the microscope 
when the apex af the angle cannót be seen, and when its two sides can- 
not be brought into the field of view at once. Mr. Briinnel, of the 
firm of Voight & Hochgesang, has invented a heating ‘apparatus, 
attachable to any microscope, for use in mineralogical investigations. 
New Books, etc.—The ninth annual report of the State Mineral- 
ogist of California contains statistics of the mineral products of the 
State for the year 1889, and accounts of the geology of the mining 
districts.”. The Mineral Resources # of the United States for 1888, 
though late in appearing, is as welcome an addition to mineralogical 
literature as any of its predecessors have been. The wealth of informa- 
tion within the 630 pages of the present volume defies abstraction. 
The value of the metallic products of the country for the year in review 
exceeded the value of those mined in 1887 by about six millions of 
dollars; while the non-metallic products were larger by seventy-two 
millions than those of the preceding year. The totals for 1888 are: 
Metallic products, $256,257,517 ; non-metallic products, $322,293,159; 
unspecified, $6,000,000; grand total, $584,550,676. Of especial 
scientific interest is the description of the occurrence and association 
of the tin ore of the Black Hills, Dak. The third part of Hintze’s 
Mineralogy, which has but recently appeared, concludes the tourma- 
line group of minerals and takes up the humite, helvine, melanocerite, 
and other groups of rare silicates, as well as dioptase, staurolite, bem- 
entite, prehnite, and individual minerals of less common occurrence. 
*4 Am. Jour. Sci., Aug., Be 120. 
45 Zeits. f. Kryst., XVIII., p. 277. 
56 Neues Jahrb. f. Min., sig oo i p. 87. 
4 Wm. Ireland. Ninth Ann. i 2 the State Mineralogist for 1889. Cal. State 
Miner. Bureau, Sacramento, Cal. 
48 D, T. Day. Mineral Resources of the United States for 1888. Washington Govt. 
Print. Office, 1890. 
in Leipsig. Veit & Co., 1890, pp. 321-480, 79 Fig. 
