Mineralogy and Geology. 429 
“A piece of properly ae era photographic re is now placed 
between the two plates of gla the movable frame ; the frame is 
removed (in a box made vetrpaboty for excluding light) poy is sus- 
pended in the long case ; this is closed, so as to prevent the possibility 
of extraneous light entering with it; the clock is started, and the time 
of starting is n noted. 
* All that part of the paper which is made to pass over the slit in the 
screen, by the motion of the clock, becomes now therefore successively 
o 
lower parts of the pendulums of the electrometer are projected through 
the slit. ‘These small portions of course retain the light color of the 
paper; and form the long curved lines or bands, whose distances from 
each other, at any given part of the photograph, i. e. at - given time, 
indicate the electric tension of the atmosphere at that tim 
“ By certain additions to the instrument above dinevidied, the kind as 
well as the tension of electrical charge is capable of being —— 
and by the employment also of a horizontal thermometer, &c., it is 
sem to the purposes of a Thermograph as well as iabimenies 
graph and Magnetograph.” 
IL. MINERALOGY AND GEOLOGY. 
1, Buratite, a new Mineral; by M. Detesse, (Comptes aii 
Oct. 26.)—This mineral is a hydrous carbonate of zinc, copper and 
a, 
Withdbanisth, CO2 
Buratite has been riot in the copper mines of Lotefskoi in the Al- 
tai mountains, at Chess sy near Lyons, at Temperino in Tuscany, a and at 
several ies localities, 
ite, a new Mineral; by L. Svanzerc, (Arsb. Berz., 1846, 
p. 240, at his mineral, from Gropptorps, constitutes a rose ‘red to 
and on sata gave, silica 45 008, alumina 22548, oxyd of iron 
me 4-548, magnesia 12: 283, ie 5227, soda 0:215, ots 110, 
med 
ite in posit io 
3. Hersch, (Ann. de Ch. a de Phys., xiv, 97. psomegihhi Poa to 
sanenec or R°Si 2+3A1Si?+1 15H. The aig agrees very 
Closely with Thomson’s analysis of the variety Levyne 
4. Aspasilt a new Mineral; by M. Se anpaxe. (Arsb. Berz 
1846, p. 24 Segre ens occurs with iolite, quartz, feldspar ea 
mica at Krageré, in Norway. It resembles iolite in erystalline form, 
has a greenish aalay. the hardness of calc spar, and the specific gravity 
