The total area is more than half of the United States (without Alaska), and the total present population is less than one eighth of the population of the United States.
It is difficult, perhaps impracticable, to divide States once created. Although a respectable minority in California and Texas favor division schemes, which would make of the former three States, and of the latter four, the tendencies of the time are against it. But with the Territories it is different; and if admission is long delayed, so that irrigation developments will have enabled the soil to sustain a dense population, such Territories as Arizona, New Mexico, and Utah are very likely to be divided. Eastern Oregon and Washington are separated by diverse interests from the western slopes of those States in somewhat the same way as southern California is separated from the northern counties. If the desire for smaller States should increase in the future, it is not impossible, therefore, that the States and Territories of the arid belt should some time contain twenty-five or thirty political divisions instead of sixteen, as at present. It is perhaps too much to say that the balance of power can ever be transferred from the Mississippi Valley to the ultimate West of the Rockies, the Great Basin, the valley of the Rio Grande, the irrigated leagues of the Nevada and Arizona deserts, the vast valley plains of the Sacramento and San Joaquin, the mountains of Coast Range, Cascade, and Sierra. But if such a change is ever brought about, the irrigator will be the principal cause of the transfer of leadership from the man of the corn lands to the man of the fruit lands.
Twenty years ago no one in America knew how to utilize water on a large scale for irrigation. A few colonies in different parts of the arid zone, a few settlers in isolated valleys, were making experiments. Half a dozen ranchers would come together and plow an open ditch two or three feet wide, to irrigate their crops in years of severe drought. As for the districts where the average annual rainfall was below the required amount, no one tried to live there. But some of the most successful of recent enterprises have been upon lands where there is "no rainfall." Even ten years ago, though the number of colonists had increased, the total area under water ditches in the arid region was hardly more than two million acres. In 1886 it had increased to five and a half million acres, and the following table shows the state of affairs in 1891: