328 I HE IRRIGATION AGE. 



Underflow is a natural movement of water through the subsoil out- 

 ward from streams or downward from catchment areas toward the 

 country drainage. Underflow irrigation consists in reinforcing this 

 flow, or in imitating it by bringing water to follow the same course 

 of distribution. 



It is an available method, first, where the ground water is natur- 

 ally near the surface and irrigation water is easily obtained in large 

 quantities; second, where an open soil through which water spreads 

 readily is found resting upon an impervious hardpan, or slightly per- 

 vious clay, which prevents loss of water by percolation. In both of 

 these conditions the method of irrigation is the same, viz, to open 

 deep furrows at considerable distances apart and keep them filled with 

 water for a considerable time, so that it may soak away in large quan- 

 tities. The addition will in the first case raise the ground water so 

 that it will rise by capillarity to the plant roots; in the second case 

 the irrigation water will spread through the free soil, flowitfg along 

 the surface of the h^rdpan or clay, and will thus become available to 

 plant roots. These methods are most apt to be useful with deep root- 

 ing trees and vegetables, but they are also used, where the conditions 

 are favorable, for grains and garden crops. 



IRRIGATION BY SPRINKLING. 



Irrigation by sprinkling is a method which, so far as the writer 

 knows, is not pursued for any commercial purpose in the irrigated 

 regions of the country. It does, however, sustain itself on the ground 

 of commercial advantage in the Eastern States, as has recently been 

 shown by Professor Voorhees, 1 and the data which he presents should 



irrigation in New Jersey, U. S. Dept. Agr,, Office of Experiment Stations Bui. 87. 

 be carefully considered by those who contemplate recourse to irriga- 

 tion as a protection to high value crops against occasional deficiency 

 in summer rains. 



LITTLE JOHNNIE'S ERROR. 

 Little Johnnie took a mirror 



And he licked the back all off, 

 Thinking: in his childish fancy, 



It would cure his whooping cough. 



Bt on the morning of his funeral 

 The neighbors said to Mrs. Brown, 



'Twas a chilly day for little Johnnie 



When the mercury went down. 

 Boston Traveller. 



