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1885.] Mineralogy and Petrography. 1213 
extensive works dealing with their classification and the results of 
their microscopical and chemical study. These are, moreover, 
quite se in their aim and scope. 
First may be mentioned Dr. M. E. Wadsworth’s Lithological 
Studies! the frst part of which, published in October, 1884, con- 
tains much useful information regarding meteorites. The results 
of the microscopical study of thin sections of these bodies by 
many investigators, as well as by Dr. Wadsworth himself, are 
properly classified with terrestrial rocks as a part of the same 
series, in which they also represent certain members more basic 
than any found in the earth’s crust near its surface. 
Probably the work which will do most to spread abroad just 
and accurate ideas of the exact nature and mineralogical com- 
position of the meteorites, is the series of microphotographs re- 
cently published by Professor G. Tschermak, of Vienna.? There is 
scarcely any one to whom a richer collection of this rare material 
was accessible, nor any one better fitted by his own researches for 
successfully preparing such a volume. Thin sections, one hundred 
in number, illustrating every phase of structure and composition 
met with among meteoric stones, have been reproduced so ad- 
mirably by photography as to afford the best possible substitute 
for the originals. When it is remembered how few can ever hope 
to thoroughly study sections of meteorites themselves under the_ 
microscope, the value of these photographs, which necessarily 
far exceed any possible descriptions, will be appreciated. Each 
plate is accompanied by a full explanatory text. The work was 
executed by J. Grimm, of Offenburg, who is already well known 
for his superb microphotographs of rock sections, edited by Pro- 
fessor E. Cohen. The same firm promises a similar set to illus- 
trate the structure of meteoric irons, the appearance of which 
will be awaited with interest. 
Professor Staislas Meunier, of Paris, has recently published an 
elaborate work entitled “ Les Météorites.”3 In this he presents a 
new classification, as well as his views respecting the origin of 
these bodies. The latter agree with those of Reichenbach, 
Haidinger and Tschermak in considering meteorites, at least such 
as possess a breccia-like appearance, as aggregations of much 
smaller bodies of matter distributed through space, which have 
been brought together by their mutual attraction. 
Another extremely important paper on meteorites is that b 
Dr. Aristides Brezina, curator of the royal mineralogical cabinet 
1 Memoirs a Comp, Zool. at Harvard Col. Vol. x1, pt. 1, Oct., 1884. 
1 Die mikroskopische Bona der Meteoriten, erläutert durch photo- 
graphische Abbildungen. Stuttgart 
3 Les Météorites. Paris, 1884. ee to Vol, 11 of Fremy’s Encyclopédie 
Chimique. 
