316 J. Trowbridge—Hffect of Great Cold upon Magnetism. 
m ‘ 
metacinnabarite is 7°70-7°74; of the Utah onofrite, 7°61—7°63 : 
of guadalcazarite, 7:15; of tiemannite, 7:15-7-274. 
Se Hg Zn Mn Fe 
uartz. 
Metacinnabarite.13°82 ... 85°79 ... -_. 0°39 0°25 =100°25 Moore 
Guadaleazarite_.14°01 tr. 83°90 2°09 _.. _.. -..=100- Rammelsberg. 
0. 14 POSiIO%1S 4:998° oo. tr. ... = 99°62 Petersen 
Onofrite, Utah_.11°68 
Gar mete Onorenla el (640) Ol os. ee ee Ba 98 
Tiemannite__._. O10 23°61) 1402 ek 98°83 Se 
a) with trace of cadmium. 
H. Rose. 
hultz. 
barite or tiemannit 
New Haven, January 12, 1881. 
—_ 
Art. XXXIX.—The Effect of Great Cold upon Magnetism ; by 
JOHN TROWBRIDGE. 
condition than has been noticed by previous obser 
* Jour. f. prakt. Chem., II, ii, 319, (1870) and this Journal, III, iii, p. 36. _ 
+ Daguin, Traité de Physique, nouv. ed. Influence de la temperature d’aiman- 
tation. ; 
