Astronomy. 137 
few cases, when the whole mass was fused, all evidence of a previous 
history has been obliterated; and on solidification a structure has been 
produced quite similar to that of terrestrial volcanic rocks. Such meta- 
morphosed or fused masses were sometimes more or less completel 
: borhood of the sun, at a 
period indefinitely more remote than that of the occurrence of any of the 
facts revealed to us by the study of geology—at a period which might 
in fact be called pre-terrestrial. 
Broomfield, Sheffield, July, 1865. 
2. On the Mineralogical Structure of Meteorites ;* by H. C. Sorsy, 
FRS.—For some time past I have endeavored to a : 
of Meteorites the principles I have made use of in the investigation of 
terrestrial rocks, as described in my various papers, and especially in 
that on the microscopical structure of erystals (Quart. Journ, Geol. Soc., 
P 
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tonal 
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much time; yet, not wishing to postpone the publication of certain facts, 
: Purpose now to give a short account of them,.to be extended and com- 
Pleted on a subsequent occasion.” 
., In the first place it is important to remark that the olivine of meteor- 
ites contains most excellent “ glass-cavities,” similar to those in the olivine 
of lavas, thus proving that the material was at one time in a state of 
io 
ver won in volcanic minerals, thus indicating the presence 
Vapor (Aussun, Parnallee). To see these cavities distinctly, a caretull 
Prepared thin section and a magnifying power of several hundreds are 
quired. The vitreous substance found in the cavities is also met with 
: ; From the Proceedi of t ‘ June 16, 1864. 
refer ames given thus (Stannern} indicate what, meteorites I more particularly 
in proof of the various facts previously stated. 
_ AM. Jour. Scr.—Seconp Serres, Vou. XLI, No. 121.—Jax., 1866. 
18 
