110 W. Gibhs—Analytical Notices. 
would only bring confusion. This is the more to be regretted, 
since the name of Chladni would be a most appropriate affix to 
a mineral, the true and pure type of which is so preéminently 
that in meteorites. 
Tn this connection I would refer to the simple chemical rela- 
tion of three of the most characteristic minerals of meteoric 
stones; these minerals forming at least 90 per cent of the earthy 
minerals in the aggregate mass of all meteoric stones. The 
three minerals are: 
Enstatite, R Si Mg = Si. 
Bronzite, Rk Si (Mg Fe) Si. 
Chrysolite, R, Si (Mg Fe) Si. 
In these minerals, the protoxide of iron replaces but a small 
ortion of the magnesia in the last two; so they are virtually 
silicates of magnesia containing one or two atoms of silica with 
one atom of magnesia. 
Art. XIV.—Analytical Notices ; by Woutcort Grsss, M.D. 
1. On the quantitative estimation of chromium and the separation 
of chromium from uranium. 
THE quantitative separation of chromium from uranium 
appears not to have specially attracted the attention of chem- 
ists.) No method is given either by Rose or by Fresenius. 
The two metals rarely, if ever, occur associated in the mineral 
kingdom, and the only definite artificially prepared compound 
which I have been able to find noticed is the uranic chromate 
described by Jahn, who does not appear to have analyzed the 
salt, though Berzelius—judging probably from the mode of 
formation—attributes to it a formula which we should now 
write U,9, .Cr®,. Berzelius also states that neutral potassi¢ 
chromate gives with uranous chloride a yellowish-brown pre- 
cipitate, which contains both oxides of uranium as we 
chromic oxide and acid. This compound also appears not to 
have been analyzed. 
cipitated chromate ous, and has a 
when the precipitation takes place in the cold. I find that a 
