At Forts Lancaster and Davis, oak wood is hauled from a distance of seven miles to supply the military posts. Along the Rio Grande universally the fuel is the root of the mezquit tree, a sort of underground forest; it burns with as hot a fire as hickory wood, and makes superior charcoal. Cotton-wood is used along the Rio Grande valley, being the fuel used in some places. We found wood scarce all the way from the Rio Grande to the Maricopas; from thence to Fort Yuma along the Gila abundant; then it is scarce over the desert; at the watering places, however, enough can be found in spots not remote from the wells; once among the San Diego mountains there is wood enough. Over these portions of our road where we find no wood at the springs or watering holes, and for want of time cannot wander off among the mountain gulches to look for it, we secure enough for all purposes of cooking from the great abundance of roots generally found just cropping out of the ground; these make an excellent fire. An examination of my table of distances will show no want of water along the route; all my measurements are to and from well known watering places. From San Antonio our road is extremely well watered until we reach the head of the San Pedro or Devil’s river, a distance of 218 miles; going west thence, we have a jornada of forty-four miles; thence another of thirty miles, between permanent roads, on to the Pecos. In the rainy season there are plenty of places in this distance where the water stands in natural tanks in the rocks, or in cañons. This stretch of forty-four miles is the longest we have on the road between permanent water stations; it forms however no great obstacle to staging. We haul water for ourselves in kegs, and the mules, having to go about twelve to sixteen hours without it, do not suffer in consequence. We have no scarcity of water in Arizona for our present purposes.--(See schedule of distances.) Our watering places on the desert west of Fort Yuma are by no means far apart, but the supply is limited at all times. It will be a matter of absolute necessity to enlarge them before the overland emigration of this spring reaches the desert. The improvement of those now used, as well as the digging of others, will be very easily accomplished. I am of opinion that the chances of procuring water by boring artesian wells on the elevated table lands, over which our road runs, may be considered as very limited. At any rate, as a practical mode of procuring water for us, it will not do. Supposing Captain Pope should demonstrate the feasibility of boring these artesian wells, even then private individuals cannot afford to make them, neither can they wait for government to do so. We should be compelled, in staging across the continent at a rate of speed necessitating the erection of stations, to adopt the old Mexican method of building tanks wherever the natural formation of the country admits of it which it does in numerous places along our road.