74 
TRANSACTIONS OF THE TEXAS ACADEMY OF SCIENCE. 
of these streams, onty a small part can be watered by the ordinary flow. 
By building immense dams across their channels, and storing the “ storm 
water” at various points along the streams, nearly the whole of these 
lands can be irrigated. 
But for the lower plateaus and the valleys of the non-perennial streams, 
this water can not be made available, and for them another system must 
be devised. Under this head are included by far the greater percentage 
of fertile and tillable lands; hence a s} r stem that will water these will be 
of very great importance. In many cases small areas can be irrigated 
from surface and artesian wells, but irrigation by this system has proven 
costly and impracticable on a large scale. It is with “storm water” 
stored in impounding reservoirs that these lands must be watered; it'is 
the best and only system practicable, and it is to this system that the 
greater part of the semi-arid lands must look for reclamation. 
The water that collects and flows on the surface of the earth during 
and after storms is commonl}*' termed “storm water.”. It flows down 
the natural water courses, filling the dry channels of the periodical 
streams, and increasing the ordinary flow of the perennial ones. With 
reference to these latter streams, this extraordinary flow is called its 
“ storm water,” and must not be confused or classed with the ordinary 
flow, which is usually derived from other sources than surface. 
Major C. E. Dutton, in a recent address on irrigation, delivered be¬ 
fore the San Antonio Scientific Society, considers the advancement of the 
science of irrigation divisible into four successive stages. The first two 
affect the use of the perennial waters of streams; the third utilizes the 
storm water of streams; and the fourth impounds the storm water from 
catchment areas in storage reservoirs. There can be no doubt but that 
the third and fourth stages will eventually become the most important to 
the people of Texas. 
Prof. E. T. Durable, who is an authority on questions of this nature in 
Texas, in a paper read before the Irrigation Convention at San Antonio, 
gives the systems of irrigation, in the order of their importance to the 
State of Texas, as follows: First, “ use of storm waters;” second, “ use 
of the flow of the perennial streams third, “artesian ivells.” 
Irrigation by use of “ storm water” is properly divided into three 
systems. The first considers the storage and use of the “storm water” 
of the perennial streams; the second, the storage of the “storm water” 
that flows down the non-perennial water courses; and the third, the col¬ 
lecting and storing of the “storm water” from local limited catchment 
basins in tanks or excavated reservoirs. 
The first two are very important, but on account of the few peren¬ 
nial streams in the arid districts, the latter are of broader scope, and 
deserve at least equal consideration. Across the beds of the greater 
