for the first time the Rio del Norte; they consist of black amygdaloidal basalt.
July 25.–Camped at noon in Joya, (five miles,) another small town, near the river. In the afternoon we had to cross a steep hill. On such occasions the teams had to be doubled, and one wagon after the other to be pulled up, causing a delay of many hours. In the afternoon we went about three miles, and camped again on the river.
July 26.–Passed in the morning through the town Sabino, and camped beyond it on the river, (10 miles.) Our night camp was five miles further, (near Parida.) The vegetable creation in the valley of the Rio del Norte, characterized principally by a great many sand plants, exhibits since a couple of days two specimens of shrub, which for their extension over the greatest part of Mexico, and their daily appearance hence, deserve a particular notice. The one is the so-called mezquite, a shrub belonging to the family of the mimmoseæ, and a species of algarobia. It resembles in appearance our locust tree; is very thorny; bears yellow flowers and long pods, with a pleasant sour taste. The wood is compact and heavy, and here, where they grow but as shrubs, used only for fuel. The mezquite requires a sandy, dry soil, and is no doubt the most common tree in the high plains of Mexico. Pleased as I was with the first sight of the shrub, which I knew only by description, I soon got tired of it, when daily and hourly I saw it around me, and the more particularly when passing afterwards from Chihuahua to Monterey and Matamoros, through endless chaparrál, of which it forms the constant companion. It grows here seldom higher than from five to ten feet, but in the southern parts I have seen them as large trees, from 40 to 50 feet in height.
The other new companion to which I alluded is the yucca, resembling in appearance the palm tree, and therefore commonly called palmilla. There are many species of this family, but they all have very fibrous, straight, pointed leaves, forming a crown on the top, and leaving the stem bare, and a cluster of white, bell shaped, numerous flowers, hanging down generally, from their weight, in a bunch of from one to two feet in length. The first very diminutive species of this plant, from two to three feet high, (yucca angustifolia,) I had seen on the Arkansas and near Santa Fe; but here a much larger species begins, which becomes every day now more common and taller. We see it here already at a height of from six to eight feet, while south of Chihuahua, especially between Parras and Saltillo, a still larger species is found, growing as trees, of several feet diameter and from 40 to 50 feet elevation. The root of the palmilla is in this country often used for washing instead of soap, and called amole; it is a fibrous, spongy mass, containing mucilaginous, and probably even alkaline parts. The wood of the palmilla is too porous and spongy to become very useful; nevertheless, in the south the poorer classes build their huts entirely of this tree.
July 27.–Having made but two miles in the morning, we met with good grass on the river and halted, as our animals had fared very badly last night. In the afternoon we had to ascend a steep, sandy hill; some of the wagons were upset, and after long delay we camped again near the river, (three miles.)
July 28.–Opposite to our road this morning, on the right bank of the Rio del Norte, was the town Socorro. As Mr. Speyer had some business with the priest of that place, I rode along. Señor el cura was a Mr.
