good; grass tolerable. In the afternoon we marched to McNees' creek, (12 miles,) but found not a drop of water in it.
June 18.–At our noon halt to-day we met with water again on Cottonwood branch, (12 miles.) Here, as well as on McNees' creek, a yellow sandstone prevails. The road is approaching nearer and nearer to the mountains. In the afternoon we passed to the right of the rabbit-ear mounds, whose resemblance to rabbit-ears, with some stretch of imagination, one may discover very easily, and arrived on Rabbit ear creek, (12 miles,) a camp with good grass and water, and cotton-trees and willows along the creek. On the right bank of the creek rise steep bluffs, formed by that porous, black looking basaltic rock, known as amygdaloidal basalt, and so common throughout the whole of Mexico. This is the first place where I have seen it in situ. It forms perpendicular walls, and is found strewed over the whole river bank. Below is a compact quartzose sandstone, as if common sandstone had been changed by volcanic action. The basalt, as well as the sandstone, lay horizontal.
June 19.–For want of water we marched 20 miles without rest, to Rock creek. About eight miles from Rabbit ear creek a mountain rises in the prairie, nearly one mile south of the road–the so-called Round mound. I ascended it, and by barometrical measurement found the difference between the foot and the top of the mountain to be 610 feet, or its absolute elevation above the sea 6,655 feet. So rapid has been our ascent since we left the Cimarron. On the top of the mountain grow cedars. The rocks composing it appear to be basaltic, in a state of decomposition; they look brown, and are sometimes very compact–sometimes more granular and friable. The view from the Round mound over the surrounding country is beautiful. The Taos mountains, in the west, are quite conspicuous; and towards the northwest I discovered high mountains–some of them with snowy summits–probably the Spanish peaks. On Rock creek I saw the amygdaloidal basalt again in situ, with its underlying sandstone.
June 20.–In the morning we made but five miles, to Whetstone creek, and halted, with good grass and water. The sandstone here contains some lime, and may be used for coarse whetstones. The amygdaloidal basalt, which I found near our noon camp, is intermixed with silicious particles, glittering like mica. In the afternoon we made 14 miles, to "Point of Rocks," the projecting spur of a chain of mountains, to our right, that here approached the road. In going to our night camp we passed extensive strata of yellow quartzose sandstone, dipping gently towards the northeast. Point of Rocks itself is a mass of large blocks of sienite, towering to the height of several hundred feet. A clear mountain spring comes out of the rock. Here we camped.
June 21.–Travelled in the morning eight miles over excellent road, and halted at noon in a ravine, or cañon, 6,486 feet above the sea. During the whole day we enjoyed a beautiful view of the mountains before and around us, the most distant of them being covered with snow. In our afternoon march I met, in the plain, with a hill of a very compact black basalt, underlaid by sandstone. In the evening we reached the Rio Colorado, (12 miles,) the principal headwaters of the Canadian river, and found an excellent camp. The Rio Colorado is a clear mountain stream, with fine grass and good soil; cedars grow on the neighboring hills, and further down on the creek. A settlement would succeed very well here.
