encounters a succession of high mountain ridges, running northwest and southeast, overlooking intermediate, unwooded and unconcealed plains, which are from fifteen to forty miles from ridge to ridge. The sierras are not continuous or united, but occur in isolated ranges of from twenty to fifty miles in extent, with smooth and clear prairie lands between them. These intervals extend from one to five miles; but as they afford neither wood nor water, are never traveled except by very small parties, which can move quickly and are too weak to risk the dangerous mountain passes and cañons. But even this cannot be effected in some places without making a detour of many miles from the direct road, and it is often indispensable to run all risks rather than lose time, or suffer the inconveniences of such a round-about and wretchedly provided march, where one is likely to perish from the want of water.
The land along the Gila is excessively alkaline and unproductive in its present condition, although in many places the willow, cotton-wood and mesquit flourish luxuriantly. In wet weather the soil becomes a soft, deep and tenacious muck, which almost wholly impedes wagon travel, and during the dry season the roads are so deeply covered with a fine, almost impassable and light dust, that every footfall throws up clouds of it yards above the traveler's head, completely shutting out from sight all objects more than three yards distant. To such an extent does this prevail in some localities, that I have been unable to distinguish the man or his horse at my side, and within reach of my arm, on a fine moonlight night.
In the immediate neighborhood of Tucson, on the table land outside of its cultivated fields, the traveler, for the first time, meets with the far-famed grama grass, but on descending from this mesa does not again come in
