158 



Kansas Academy of Science. 



glance at the map, a very large portion of the supply is obtained 

 within 150 feet of the river banks. The plan of the Lawrence 

 Water Company's collection system is shown herewith. 



The one effect that the river has on the ground water is to cause 

 it to raise or lower according to the height of the river. The river 

 does not filter back through the sand to raise the water in the 

 wells, however, but its effect is explained by the geologist in a 

 similar way to that portrayed in the accompanying sketches. 



No. 1 shows the normal condition of the river when it is flowing 

 with the bed well filled and the ground water at sufficient height 

 and working under just enough head to pass into the river against 

 the back pressure of the water in the stream. That this CDudition 

 exists ordinarily is illustrated by the fact that the flow over the 

 dam at Lawrence is one-fourth greater than the combined flow of 



Plate V. 



