410 General Notes. [ May, 
7. The Preglacial valleys (now buried) of Ohio and Pennsyl- 
vania—for example, the Cuyahoga, Mahoning (reversed), and 
Allegheny (deflected)—formed tributaries to the great river flow- 
ing through the Erie basin and the Dundas valley. 
e bays and inlets north of Lake Huron are true fiords in 
character, and are of aqueous origin. 
. The Great lakes owe their existence to sub-aérial and 
fluviatile agencies, being old valleys of erosion of great age, but 
with their outlets closed by drift. Glaciers did not excavate the 
lakes and had no important action in bringing about the present 
topography of the basins. 
10. The old outlet of the Niagara river, by the valley of St. 
David's, was probably an interglacial channel. 
Tue IRon OREs OF SOUTHERN Utau.—During the past summer, 
which I spent chiefly in Utah, I visited the deposit of crystalline 
iron ore of Iron county, in the southern part of the Territory. 
These ore beds have been long known and were to some extent 
utilized by the Mormons in their first advent, thirty years ago, 
but no satisfactory description of them has ever been published. 
As they constitute, perhaps, the most remarkable deposit of iron 
ore yet discovered on this continent, I have thought that some 
facts in regard to them might not be an unimportant addition to 
what is known of the economic resources of our country. The iron 
region referred to lies nearly three hundred miles directly south 
from Salt Lake city, and is situated in what is really the southern 
prolongation of the Wasatch mountains. The iron ores occur in 
the northern portion of a subordinate range, which attains 1ts 
greatest height in Pine Valley mountain near Silver Reef. Thirty 
miles north of this point the ridge breaks down into a series of hills 
from one thousand to two thousand feet in height, which consist 
chiefly of gray fine-grained granite, with dykes and masses of 
trachyte and here and there outcrops of highly metamorphosed 
limestone. The ore beds forma series of protruding crests and 
masses set over an area about fifteen miles long ina north-east 
and south-west direction, and having a width of three to five 
miles. Within this belt the iron outcrops are very numerous and 
striking ; perhaps one hundred distinct claims having already oy 
located upon them, each one of which would make the fortune 0 
a mining company if situated anywhere in the Mississipp! sbepcid 
or the Eastern States. The most impressive outcrops are 1 the 
vicinity of Iron springs, Oak springs and Iron city, of which lo- 
calities the first and last mentioned are about twelve miles apart. 
Near Iron springs the Big Blow-out, as it is called, is a projecting 
mass of magnetic ore, which shows a length of perhaps 4 -_ 
sand feet by a width of five hundred, and rises in castellate 
crags one hundred feet or more above its base. __ she 
At Iron springs a still more striking exhibition is made by t t 
Blair mine, which is a ragged crest of magnetite, black as J&% 
