68 Ka7isas Academy of Science. 



supplied by our rocks in such quantities that plants are not 

 likely to suffer from a lack of them. To this statement there 

 is one important exception : Water is necessary and the sup- 

 ply is scanty, in all the state sometimes and in part of the state 

 all the time. 



THE CONSERVATION OF WATER. 



In spite of its scarcity at times and in places it is evident 

 that water has played the leading part in the geological devel- 

 opment of Kansas, and in the industrial development as well. 

 It is fitting, therefore, that the paper should conclude with a 

 brief discussion of water supply and how it may be best con- 

 served. The estimates given below are adapted to Kansas 

 from some statistics quoted by President C. R. Van Hise in his 

 book, "The Conservation of Natural Resources of the United 

 States." 



The annual rainfall of Kansas totals on the average thirty- 

 seven and one-half cubic miles. Of this amount about one- 

 half, eighteen and three-fourths cubic miles, flies off very soon 

 after a rain into the air (by evaporation) . Six and one-fourth 

 cubic miles are consumed by plants, or sink very deeply into 

 the earth, so far that they do not get back again except through 

 volcanoes. At any rate, they are lost to the statistician. One- 

 third, or twelve and one-half cubic miles, runs off directly or 

 sinks into the ground and feeds springs and rivers by seepage. 

 Possibly one or two cubic miles of this ten run off at the sur- 

 face and make Kansas floods, and the balance flows slowly 

 through the ground to the rivers and keeps them going be- 

 tween rains. Many in times past have believed that wells are 

 fed from near-by rivers, but careful experiments have shown 

 that water in wells near streams stands higher than it does 

 in the stream and that the ground-water flows towards the 

 watercourse. This is true at all times except when heavy 

 rains towards the source of the river cause temporary flood, 

 when the reverse is true. 



Below this shifting surface water, to a depth of seven miles, 

 are forty times as much more, or twelve hundred cubic miles 

 of water under Kansas, which flow slowly back and forth, up 

 and down, or in a circle, deep in the crust of the earth, dis- 

 tributing and concentrating the ores and other minerals. 



All these forms of water present to the observer interesting 

 material for study, but the run-off of ten cubic miles of water, 

 rich in all the minerals that plants and animals need, demands 



