1866. ] Mining, Mineralogy, and Metallurgy. 289 
converted into steam of atmospheric pressure by one pound of 
anthracite coal. ‘This of course requires confirmation by a con- 
tinuance of the experiments. It must, however, be admitted that 
Mr. Richardson’s experiments in this country were satisfactory. 
Nitroglycerme has been much lauded as an explosive agent for 
mining purposes. It is now stated * that it freezes at a temperature 
of about 42° Fahr., when mere friction will occasion it to explode. 
In one of the Silesian mines an overseer was attempting to break a 
frozen mass, weighing about eight pounds, when it exploded, and 
the poor man was blown high into the air, and, of, course, killed. 
M. Simon communicates in a letter to M. Khe de Beaumont 
some interesting particulars respecting the Stanniferous deposits of 
Brittany. The district of Villeder consists of a system of quartz 
veins in contact with granites and schistose rocks, the direction of 
the principal veins being N.N.E. Penestin (in Breton Pen-staen, the 
Headland of Tin), Piriac, and Morbihan are all tin-producing districts, 
and it is thought that the embouchures of the Vilaine and the Loire 
were visited by Phcenicians and the Greeks in the time of Homer. 
To these pots M. Simon would call the attention of modern tin 
miners, especially as the districts correspond with the rich tin- 
bearing districts of Cornwall.t 
MINERALOGY. 
Knop has recently discovered in the decomposed and weathered 
eryolite a new mineral, to which he has given the name Pachnolite, 
from its resemblance to hoar-frost. Knop gives the chemical com- 
position as Fl. 50°79, Al. 13-14, Na. 12:16, Ca. 17°25, H. 9°60= 
102°94.t Dr. G. Hagemann, of the Alkali works at Natrona, in 
Pennsylvania, has examined this mineral, and he fully confirms M. 
Knop’s results. It appears that cryolite is now imported largely to 
Natrona from Greenland, for the purpose of manufacturing soda-ash, 
alumina salts, and other products. § 
Professor W. P. Blake states that a mass of gold, which is for 
the most part a congeries of imperfect crystals, has been found seven 
miles from Georgetown, El Dorado Co., California, which weighs 
201 ounces. || 
The amount of gold and silver produced in 1865, from the mines 
of the Montana Territory, will be sixteen millions of dollars. The 
region was a wilderness in 1862.4 
An iron ore of peculiar character has been discovered in Ireland. 
It has much the appearance of Plumbago, leaving a greasy stain 
when rubbed between the fingers, and giving off under the knife 
* «Berg und Hiitten-mannische Zeitung’ 
+ ‘L’Institut,’ Feb. 21, 1866. No. 1677. 
{ ‘Annalen der Chemie und Pharmacie,’ vol. exxvii. 
§ ‘American Journal of Science and Arts,’ Jan., 1866. 
|| Ibid. § Ibid. 
