e surface of the water in the conduit to the centre of the
opening through which it flows. This is nine gallons a minute, or, as it
is figured, 1728 cubic feet or 12,960 gallons in twenty-four hours, and
1.50 of a cubic foot a second. This flow would cover ten acres about
eighteen inches deep in a year; that is, it would give the land the
equivalent of eighteen inches of rain, distributed exactly when and
where it was needed, none being wasted, and more serviceable than fifty
inches of rainfall as it generally comes. This, with the natural
rainfall, is sufficient for citrus fruits and for corn and alfalfa, in
soil not too sandy, and it is too much for grapes and all deciduous
fruits.

CHAPTER IX.

THE ADVANTAGES OF IRRIGATION.

It is necessary to understand this problem of irrigation in order to
comprehend Southern California, the exceptional value of its arable
land, the certainty and great variety of its products, and the part it
is to play in our markets. There are three factors in the expectation of
a crop--soil, sunshine, and water. In a region where we can assume the
first two to be constant, the only uncertainty is water. Southern
California is practically without rain from May to December. Upon this
fact rests the immense value of its soil, and the certainty that it can
supply the rest of the Union with a great variety of products. This
certainty must be purchased by a previous investment of money. Water is
everywhere to be had for money, in some localities by surface wells, in
others by artesian-wells, in others from such streams as the Los Angeles
and the Santa Ana, and from reservoirs secured by dams in the heart of
the high mountains. It is possible to compute the cost of any one of the
systems of irrigation, to determine whether it will pay by calculating
the amount of land it will irrigate. The cost of procuring water varies
greatly with the situation, and it is conceivable that money can be lost
in such an investment, but I have yet to hear of any irrigation that has
not been more or less successful.

Farming and fruit-raising are usually games of hazard. Good crops and
poor crops depend upon enough rain and not too much at just the right
times. A wheat field which has a good start with moderate rain may later
wither in a drought, or be ruined by too much water at the time of
maturity. And, avoiding all serious reverses from either dryness or wet,
every farmer knows that the quality and quanti