TRANSACTIONS OF THE SECTIONS. 39 
whilst warm, and left at rest for some days in stoppered bottles at a temperature of 
about 60°, till it deposited the excess of fluor soluble above that temperature. It was 
then filtered a second time. A certain volume of the solution measured at 60° was 
evaporated to dryness on the vapour-bath, in a counterpoised platina basin, and the 
weight of the residue ascertained. 
Twenty-four pints of the solution were thus made use of. In six experiments, 
one imperial pint of the solution (16 fluid ounces, or 7000 grains) was taken at each 
trial. In four trials three pints were evaporated at each experiment. In one case 
six pints were employed. The following are the results :— 
Per pint. 
Expt. I. evap. 1 pint of solution. Residue 0°27 grs. 
Il. ” ”» ” 0°28 
Ii. ef ” par Oe 
IV. ” ”» ” 0°24 
Ve a3 2? a> 0°27 
VI. 2 » 9 0°25 Average 0°265 per pint. 
+ Per pint. 
Expt. VII. evap. 3 pints of solution. Residue 0°79 = 0°263 
Vill. » » » 0°78 = 0'260 
IX. ” 2” ” 0°78 = 0°260 
Xx. ” » ” 0°77 =0°257 Average 0°260 per pint. 
Per pint. 
Expt. XI. evap. 6 pints of solution. Residue 1°62=0°27 Average 0°270 per pint. 
Twenty-four pints of distilled water thus dissolved 6-330 grains of fluor spar; so 
that the average amount dissolved in one pint will be 0°2637 grains. One grain 
therefore of fluor will requrie 26°545 grains of water at 60° F. to dissolve it, or water 
at that temperature will take up seuagths of its weight of the salt. 
The solubility here indicated must be considered great for a salt hitherto reputed 
quite insoluble. It is still more soluble in water at a high temperature, as the de- 
posit left by warm solutions on cooling shows. These facts will now be connected 
with the appearance of fluoride of calcium in plants and animals, as well as in mineral 
veins and elsewhere, and may perhaps prove sufficient to explain these hitherto per- 
plexing phenomena. 
Analysis of the American Mineral Nemalite. By Prof. Conne.z, P.RSE. 
This mineral bears a striking resemblance to asbestus, so that by the eye it can 
hardly be distinguished from it. It was first chemically examined by Mr. Nuttal, 
who ascertained that it differs entirely in constitution from asbestus, and concluded 
from his experiments that it consists essentially of magnesia and water with a little 
oxide of iron and lime. It was subsequently examined by Dr. Thomson, according 
to whom it also contains 12 per cent. of silica. The constituents found by the 
latter were— 
Magnesia ......seseeeee . 51°721 
Silica ....cs0s Ditapvess s.. 12°568 
Peroxide of iron...... ase D874 
Water ........ seca seseee 29°666 
99°829 
The result which I have obtained differs somewhat from both the preceding. 
According to both the previous experimenters, the mineral is soluble in acids without 
effervescence. But I have found that even perfectly fresh portions of the specimens 
(which I have) of the mineral from Hoboken in America sensibly effervesce when 
dissolved in acids, showing some carbonic acid to be contained in it. I have also - 
_ found only a very minute quantity of silica, the mineral leaving scarcely any residue 
when dissolved. 
__. The amount of water was determined by ascertaining the quantity of water col- 
lected by ignition in a tube of German glass twice bent, and containing at one end 
