36 L. Semann on Geological Phenomena in the Solar System. 
remains in the supernatant liquor while the waterglass is almost 
wholly precipitated. . 
I have not yet made a sufficient number of experiments to 
] 
of the bismuth salts with water. On the one side, however, 
amorphous substances give indefinite products; on the other 
erystallizable bodies yield definitely constituted precipitates. 
Considering the large proportion of silica capable of being 
retained permanently in solution by a little alkali, the disturbing 
influence of foreign matters such as earths and neutral salts, and 
the gummy character of the silicates,—we find in the water- 
asses a reverse parallelism to the soluble basic salts of the 
sesquioxyds and binoxyds;—the excess of base in the latter 
having the same effect as the excess of acid in the former. And 
not to attribute a rational formula to any of the silicates of 
potash or soda till it can be shown to be crystallizable or to have 
a constant composition under varied influences. 
Manchester, New Hampshire, Sept. 1861. 
Art. IV.—On the Unity of Geological Phenomena in the Solar 
System; by L. SamMann. 
[From the Bull. de la Soc. Geologique de France for Feb. 4, 1861; translated by 
T, Sterry Howr, M.A., F.R.S.] 
TE observations upon the solar eclipse of J uly 18, 1860, 
have given rise among astronomers and physicists to some in- 
concerning the spots upon the sun. This great as- 
* Proc. American Academy (1861), v. p. 192. 
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