W. P. Blake—Realgar and Orpiment in Utah. 219 
connected with the rapid accumulation of the basal deposits 
of that formation. Or it may hereafter be ascertained, by a 
more minute study of the Appalachian regions of the middle 
latitudes, that glaciers established themselves at the higher 
levels in the earlier times of the Glacial period, but did not recur 
during the second accession of cold, while the more extensive 
and long-continued Diluvial denudations and erosions may 
have sufficed to remove the debris, striz and other indications 
of earlier glacial action. 
Raleigh, N. C., Dec. 24, 1880. 
Art. XXVII.—Occurrence of Realgar and Orpiment in Utah 
Territory; by Wiuu1AM P. BLAKE. 
Orizo 
spherical aggregations, made up of fine radial crystals, and also, 
In bright yellow amorphous crusts in and around the mass o 
ar. 
bank and form hard crusts. The appearance and the 
48sociation of the arsenical sulphides indicate that these sul- 
ped have been f y aqueous infiltration since he 
position of the beds. This, I have no doubt, is the fact; 
