"This vast tract, therefore, containing, as is estimated, from twelve to fifteen millions of acres, belongs mostly to the Government. South of this valley, and west of the Colorado, within the limits of California, as indicated in her Constitution, there are said to be extensive tracts of valuable, unappropriated land; and, on investigation, it will probably appear that there are many of them in detached bodies, which have not been granted.
"I do not speak of the gold region, embracing the entire foot-hills of the Sierra Nevada, some five hundred miles long and sixty miles broad, in connection with the public domain, which may be embraced in the general land system for sale and settlement, for reasons which will be hereafter assigned.
"The survey of the public lands on a system suited to the interests of the country is a matter of very great importance. In the inhabited portions of the Territory, the boundaries of Mexican grants, running as they do in all directions, will render the system of surveys by parallels of latitude and longitude quite impracticable.
"In all parts of the country, irrigation is desirable, and its benefits should be secured, as far as possible, by suitable surveys and legal regulations. Most of the valleys are watered by streams sufficiently large to be rendered very useful. It would, therefore, seem wise to lay off the land in conformity to the course of the hills and streams which bound and drain the valleys.
"A system of drainage, which would also secure irrigation, is absolutely necessary to give value to the great plain of the Sacramento and San Joaquin. This valley is so extensive and level that, if the rivers passing through it were never to overflow their banks, the rain which falls in winter would render the greater portion of it unfit for cultivation. The foundation of such a system can only be established in the survey and sale of the land.
"_This can be done by laying out canals and drains, at suitable distances, and in proper directions, and by leaving wide margins to the rivers, that they may have plenty of room to increase their channels when their waters shall be confined within them by embankments._
"It would be well also to regulate the price of these lands, so as to meet, in some degree, the expense of draining them.