The creek was three or four feet broad, and about six inches deep, with a swift current of clear water, and tolerably cool. We had struck it too low down to find the cold water, which we should have enjoyed nearer to its sources. At two, P.M., the barometer was at 25050, and the attached thermometer 104°. A day of hot sunshine, with clouds, and moderate breeze from the south. Continuing down the stream, in about four miles we reached its mouth, at one of the main branches of Horse creek. Looking back upon the ridge, whose direction appeared to be a little to the north of east, we saw it seamed at frequent intervals with the dark lines of wooded streams, affluents of the river that flowed so far as we could see along its base. We crossed, in the space of twelve miles from our noon halt, three or four forks of Horse creek, and encamped at sunset on the most easterly.
The fork on which we encamped appeared to have followed an easterly direction up to this place; but here it makes a very sudden bend to the north, passing between two ranges of precipitous hills, called, as I was informed, Goshen's hole. There is somewhere in or near this locality a place so called, but I am not certain that it was the place of our encampment. Looking back upon the spot, at the distance of a few miles to the northward, the hills appear to shut in the prairie, through which runs the creek, with a semicircular sweep, which might very naturally be called a hole in the bills. The geological composition of the ridge is the same which constitutes the rock of the Court-house and Chimney, on the North fork, which appeared to me a continuation of this ridge. The winds and rains work this formation into a variety of singular forms. The pass into Goshen's hole is about two miles wide, and the hill on the western side imitates, in an extraordinary manner, a massive fortified place, with a remarkable fulness of detail. The rock is marl and earthy limestone, white, without the least appearance of vegetation, and much resembles masonry at a little distance; and here it sweeps around a level area two or three hundred yards in diameter, and in the form of a half moon, terminating on either extremity in enormous bastions. Along the whole line of the parapets appear domes and slender minarets, forty or fifty feet high, giving it every appearance of an old fortified town. On the waters of White river, where this formation exists in great extent, it presents appearances which excite the admiration of the solitary voyageur, and form a frequent theme of their conversation when speaking of the wonders of the country. Sometimes it offers the perfectly illusive appearance of a large city, with numerous streets and magnificent buildings, among which the Canadians never fail to see their _cabaret_--and sometimes it takes the form of a solitary house, with many large chambers, into which they drive their horses at night, and sleep in these natural defences perfectly secure from any attack of prowling savages. Before reaching our camp at Goshen's hole, in crossing the immense detritus at the foot of the Castle rock, we were involved amidst winding passages cut by the waters of the hill; and where, with a breadth scarcely large enough for the passage of a horse, the walls rise thirty and forty feet perpendicularly. This formation supplies the discoloration of the Platte. At sunset, the height of the mercurial column was 25.500, the attached thermometer 80°, and wind moderate from S. 38° E. Clouds covered the sky with the rise of the moon, but I succeeded in obtaining the usual astronomical observations, which placed us in latitude 41° 40' 13", and longitude 104° 24' 36".