BYBEE-MALOTT : THE FLOOD OF 1913 



113 



half the estimated loss to soil in the recent flood. For the estimated 

 loss of soil, the whole State could Ijo ma])ped. About fifteen 

 fifteen-minute cjuadrangles would cover the greater part of the 

 valley land on both forks of White River and would cost less than 

 one-third of the estimated damage to soil in the recent flood. These 

 figures are possibly too high, for the relief in Indiana is not very 

 pronounced, especially in the glaciated part of the State. 



General Laws of a Stream 



In the work of water, as it is emphasized along any stream 

 from a mere rivulet to a great river, a few principal laws come 

 under consideration which are applied to any particular stream. 

 Since these laws are fundamental, a few pages are here devoted 

 to a consideration of them. 



'Every river appears to consist of a main trunk, fed from a 

 variety of branches, each running in a valley proportional to its 

 size, and all of them together forming a system of valleys com- 

 municating with one another, and having such a nice adjustment 

 to their declivities that none of them join the principal valley 

 either at too high or too low a level, a circumstance which would 

 be infinitely improljaljle if each of these valleys Avere not the work 

 of the stream flowing in them.' (John Playfair. 'Huttonian Theory 

 of the Earth.') 



Streams are one of the most important agencies that give 

 form and expression to the surface of the earth; they are the prin- 

 cipal factors in fashioning the details of the various topographic 

 forms that strike the eye of the every-day observer. Streams cut 

 into the plains, making valleys and hills suited to the <ize of the 

 streams and proportioned to the general elevation of the former 

 plain above the mouths of the main streams. 



Every one is aware that streams carry sediment, and espe- 

 cially after rains during high water. When one considers that 

 streams, ever and ever, are carrying sediment, he soon is able to 

 grasp the idea how streams are able to carve the surface of the 

 earth as they do. During each high water millions and millions 

 of tons of sediment are carried to the ocean. Nearly every one 

 has noticed that during the short summer shower a considerable 

 gully may be made on a hill side, that started from a little rill in 

 the mark of a harrow tooth. The soil thus removed, however, may 

 be at the foot of the same hill. In fact the soil from the source 

 of a stream may make many stops before it finally reaches the ocean. 



