They would find that the total run-off from the Colorado River watershed that now runs to waste is enough to irrigate 5,000,000 acres of land located in the main valley of the river between the mouth of the Colorado Canyon and the Mexican boundary line. They would find that the area of land so located that can be irrigated by gravity canals is 2,000,000 acres; that 1,500,000 more acres can be irrigated by pumping with electric power generated in the river, and, from the best information now obtainable, that the area irrigated by pumping can eventually be enlarged another 1,500,000 acres, making a total in all of 5,000,000 irrigable acres in the main Colorado River Valley, including the Imperial Valley and the valley above Yuma. Including the entire watershed or drainage basin of the Colorado River, and all lands irrigable from underground supplies, and enlarging the irrigable area to the fullest extent that it would ultimately be enlarged by return seepage, they would find that they could eventually irrigate more than 12,500,000 acres, which is as much land as is now irrigated and cultivated in Japan. They would figure on _acreculture_ rather than _agriculture_, and would investigate to the minutest detail the problem of fertilization. They would figure on handling the silt of the Colorado River just as the silt of the Nile is handled in Egypt, fertilizing as large an area as possible with it. The Colorado River carries silt that is very fine and enough of it could be brought in the water every year to practically every irrigated field, to maintain the incredible fertility and productiveness of the bottom lands and increase that of the mesa lands. They would look for phosphate, potash, and nitrogen for fertilizers. They would find that an inexhaustible supply of potash could be manufactured from the giant kelp beds of the Pacific Coast. They would learn that there are in the territory included in the drainage basin of the Colorado River unlimited deposits of phosphate rock from which all needed phosphate could be mined. Nitrogen, they would ascertain, could be produced from the air in immense quantities by the use of the electric power which could be developed without limit in the canyon of the Colorado River. They would utilize for that purpose all the vast surplus of electric power from the Colorado River as it whirls and plunges down the most stupendous river gorge in the world. In addition to producing all they needed to fertilize their own lands they would produce enough nitrogen, potash and phosphates to supply the markets of the world.