"The ores of Chihuahua and Sonora [now Arizona. S. M.] are chiefly sulphuret (lead or iron), or native silver in porphyritic or stratified limestone rocks passing at greater depths into igneous rocks. From loose piles lying upon the surface and evidently picked over, I procured specimens of silver and copper. Three samples representing points on the line of our exploration about equi-distant from each other, viz.: the Rio Grande, the neighborhood of Tubac, and within 90 miles of the junction of the Gila and Colorado rivers, were submitted to Dr. I. K. Chilton, of New York, for analysis. He found in one sample of lead ore (argentiferous galena), by fire assay 71 per cent. of lead, and the "LEAD YIELDED SILVER EQUIVALENT to 128 ounces, 1 dwt. to the ton" (of 2000 pounds). "In another, he found the lead obtained from it to yield silver in the proportion of 72 ounces 5 dwts. to the ton or 2000 pounds. "The copper specimen was the red oxide, and yielded as follows: Copper,............ 71.80 Iron,.............. 7.84 Oxygen,............ 12.34 Silicia, Alumina,.. 8.02 ------ 100 parts. "The Papagos and Pimas Indians, by proper management, might be made very useful, in working upon the road where there is not much rock excavation. They are unlike the Indians of Texas, or the Apaches, living in villages and cultivating the soil, besides manufacturing blankets, baskets, pottery, etc. Quiet and peaceable, they have no fears except from their enemies, the Apaches, and are very industrious, much more so than the lower order of Mexicans, and live far more comfortably. It is astonishing with what precision they construct their acequias--irrigating canals--some of them, the acequias madre, of very large size, and without the use of levelling apparatus, but simply by the eye. Their gardens and farms too are regularly ditched and fenced off into rectangles and circles, with hedges and trees planted as if done by more enlightened people."