We AS ea 
Table of Atomic Weights. 217 
Before the blowpipe it exfoliates and becomes a little yellowish 
or brownish, and gives the reaction of magnesia. Dissolves with 
effervescence in acids. 
We observe that Hermann has made a new mineral—which 
he calls Pennite—of the white and greenish incrustation of car- 
bonate of magnesia accompanying Emerald nickel at Texas, Pa., 
and which, as we have remarked, appears to graduate into the Em- 
erald nickel. He finds for its composition, carbonic acid 44-54, 
lime 20:10, magnesia 27-02, nickel 1-25, protoxyd of manga- 
nese (40, alumina 0:15, water 5-84 = 100, giving the formula 
3(Mg, Ca, Ni)6+H, H=3'5. G.=2-86. 
e have not yet had opportunity for trials to ascertain how 
far the water is a constant ingredient. 
Art. XXIV.— Table of Atomic Weights. 
Tue recent investigations of science, while evincing the con- 
summate skill of the Swedish chemist, are introducing changes 
rom time to time in the Berzelian atomic weig 
chahges are in part the result of direct experiment on the particu- 
lar substances, and in part an indirect consequence of these new 
determinations ;—a change of one element involving necessarily 
a change in those other elements which were determined by 
using that one in the data. The following table is here inserted 
Son and choice to such as would use them, and especially for 
Comparison with the new determinations that may hereafter be 
made. 
_ The number of elements as now recognized is sixty-two, forty- 
nine of which are metals. J. D. D. 
Szconp Srnies, Vol. IX, No. 26.—March, 1850. 28 
