AVAILABLE WATER SUPPLIES. 



105 



Uppir Mississippi 



crsof tlwUnitrcl sialea. 



Fig. 4. 



Connecticut and with the Potomac in average dis- 

 charge, but is far below the latter in maximum flood. 

 The last three lines of the diagram show the relative 

 size of the Missouri, upper Mississippi and Ohio, 

 previously discussed. It is apparent from this dia- 

 gram that the flood of the upper Mississippi does not 

 reach the average discharge of the Ohio, while the 

 flood of the Missouri is not much greater than the 

 average flow of the upper Mississippi. 



The relative size of the rivers of the west cannot be 

 shown on the diagram just mentioned, and therefore 

 a different scale has been chosen for diagram, figure 

 5. In this case, as in the other diagram, figure 4, 

 the black portions of the bar indicate the minimum 

 discharge, the shaded portions, including the black, 

 show the average and the' open portions, including 

 the black and shaded, give the maximum discharge- 

 The width of the diagram allows only about 17,000 

 second feet, and in two cases, those of Salt and Snake 

 rivers, the diagram is incomplete as regards the flood, 

 this being shown in full upon figure 4 just described. 

 A comparison of these lines brings out the difference 

 in quantities of water in the streams better than any 

 figures. The basins from which 

 this water comes are indicated 

 upon the map, figure 2, which also 

 shows the approximate size of the 

 basins and the places where meas- 

 urements were made. 



