388 SciM^c Intelligence. 
\ 
within about four or five acres of ground. The quantity of 
j)ure nitrogen gas^ or azotic gas,' which issues in the form of 
bubbles from these springs, is incalculable. The gas does not 
seem to be combined with the water, but to issue from the gra- 
vel-beds beneath the water of the springs : and we have no good 
reasons for saying that the gas is confined to the beds of these , 
springs. It may continually issue from the dry' parts of the 
soil in their immediate vicinity, and become manifest only where 
the water covers the soil, by bubbling through it. By pressing 
upon a surface of the gravel equal to five or six inches square, 
a quart of the gas may be collected in an inverted jar or bottle, 
in ten seconds. 
By what process in nature is such an abundance of gas inces- 
santly produced ? About three -fourths of the atmosphere is ni- 
trogen gas ; and we are acquainted with no other extensive re- 
servoir of this substance. If it is derived from the atmosphere, 
how is it introduced into this situation ? Or, if this process of 
nature should be explained, how is the oxygen of the atmo- 
sphere separated from the nitrogen ? — Eaton’s Geological Sur- 
vey (^Rensselaer County^ p. 29. Albany, 1822. 
13. Analysis ()f Gihhsite, a new Mineral. — This new mineral, 
named after Colonel Gibbs, was discovered by Dr Ebenezer 
Emmons, in a neglected mine of brown hsematitical iron-ore in 
the town of Bichmond, in Massachusets. 
It occurs in small irregular stalactitic masses, from 1 to 3 in- 
ches in length, and 1 inch, or more, in breadth, consisting of an 
aggregation of elongated tuberous branches, laid parallel, and 
united together. 
It is rather harder than, calcareous spar, is slightly translu- 
cent, and has--a specific gravity of 2.40. It does not effervesce 
with acids, and whitens before the blowpipe. 
According to the analysis of Dr Torrey of New-York, its com- 
position is, 
Alumine, 
. 
- 
64.8 
Water, 
. 
• 
34.7 
Loss, 
- 
• 
1.5 
100.0 
Hence this mineral is a Hydrate of Aluminey and is the same 
as what Wavellite was supposed to be, before Berzelius detect- 
