Chemistnj. 585 
or fire of musqiietry, and a continued rolling. At that momenlj 
a stone fell about 5| German miles from the country palace 
of Lixna, in the circle of Dunaberg. The stone penetrated 
feet into a clayey loam. It weighed 40 lbs., had the smell 
of gunpowder, and was hot to the touch. At the same time, a 
large body fell about four wersts distant into the Lake Kolup- 
schen with a hissing noise, and dashing the spray high into the 
air. Three wersts in the opposite direction, something fell into 
the river Dubna, which made its water turbid for about an hour. 
The analysis of this stone is given in p. 389. 
II, CHEMISTRY. 
15. On the Combmation the Earths with Platinum^ ^c . — ^ 
By John Murray, Esq. Lecturer on Chemistry. 
In the Annates de Chimie^ are given the result of some experi- 
ments by M. Boussingalt, from which it appears, that Silica 
may be made to combine with Platinum and Iron. With the 
latter metal I made no experiments, but several with platinum, 
which prove, that not only silica may be made to combine with 
it in the formation of its alloys, but that the earthy combination 
is not exclusively confined to silica, as I have in like manner 
united Alumina^ Zirconia^ Glaucma^ Baryta^ By this 
statement, it must be evident that the class which comprises the 
alloys of platinum is capable of great extension ; nor have we 
any authority to limit the combination of earths to platinum, or 
even to steel. The conclusions of Cloult and of Boussingalt 
receive also confirmation from the following remarks. 
It may be remarked, that what M. Boussingalt referred to 
carbon^ from its taking fire, &c. might have been silica ; for, if 
a portion of pure silica be put on paper, and the paper set on 
fire, the silica will be also ignited, and it finally becomes brown, 
giving off delicate streams of minute sparks, and the silica thus 
recoiling on the , paper, by the advance of the flame is thrown 
into beautiful undulations or waves. Both the protoxide and 
deutoxide of Barium, under similar circumstances, inflame like 
nitrate or oxymuriate of potassa. I have already stated, that if 
antimony, bismuth, zinc, tin, &c. be wrapped up in platinum- 
foil, and held in the flame of a spirit-lamp, a brilliant ignition 
ensues, and the fusion of the alloy is complete. 1 use a metal- 
