Produced by Dianne Bean. HTML version by Al Haines. MEMOIR OF THE PROPOSED TERRITORY OF ARIZONA. BY SYLVESTER MOWRY, U. S. A., DELEGATE ELECT. WASHINGTON: HENRY POLKINHORN, PRINTER. 1857. "The NEW TERRITORY of ARIZONA, better known as the GADSDEN PURCHASE, lies between the thirty-first and thirty-third parallels of latitude, and is bounded on the north by the Gila River, which separates it from the territory of New Mexico; on the east by the Rio Bravo del Norte, (Rio Grande), which separates it from Texas; on the south by Chihuahua and Sonora, Mexican provinces; and on the west by the Colorado River of the West, which separates it from Upper and Lower California. This great region is six hundred miles long by about fifty miles wide, and embraces an area of about thirty thousand square miles. It was acquired by purchase from Mexico, during the mission of General Gadsden, at a cost of ten millions of dollars. In the original treaty, as negotiated by General Gadsden, a more southern boundary than the one adopted by the Senate of the United States in confirming the treaty, was conceded by Santa Anna. The line at present is irregular in its course, and cuts off from our Territory the head of the Santa Cruz river and valley, the Sonoita valley, the San Bernardino valley, the whole course of the Colorado river from a point twenty miles below the mouth of the Gila river, and, worse than all, the control of the head of the Gulf of California, and the rich and extensive valley of Lake Guzman, besides a large and extremely valuable silver region, well known both to Mexicans and Americans--the planchas de la Platte. General Gadsden's line included nearly all the territory south of the Gila river to the thirty-first parallel of latitude--all the advantages above mentioned--gave us the mouth of the Colorado river, and probably a port near the head of the gulf at Adair's Bay. We have no accurate survey of the west coast of the Gulf of California, but I am strongly of opinion that the original line conceded by Mexico would have thrown a portion of the gulf into American hands, by cutting off an arm of it extending east and north from the main body of water. A port on the gulf is of great and immediate necessity to our Pacific possessions. Of this hereafter. The proposed boundaries, of the Territory of Arizona, are the 34th parallel of latitude, with New Mexico on the north, from the 103d meridian west to the Colorado; Texas on the east; Texas, and the Mexican provinces of New Mexico and Sonora on the south; and California on the west. The new Territory would thus contain within its borders the three largest rivers on the Continent, west of the Mississippi--the Rio Grande, Gila, and Colorado of the west, and embrace 90,000 square miles.