140 IRRIGATION OF LAND. 



one of the most useful and important of all the operations that come 

 ■within the province of the farmer." Sinclair says, " a productive 

 water meadow is probably the true mark of perfection in the man- 

 agement of a farm." Pusey says, " a water meadow is the triumph 

 of the agricultural art." Stearns speaks of irrigated meadows yield- 

 ing over five tons of hay to the acre, and Liebeg speaks of from 

 three to five perfect crops being obtained in a season from watered 

 meadows. The benefits of irrigation are owing to the operation of 

 several natural laws acting in combination. The tendency of water, 

 for instance, whenever it comes in contact with the surface of the 

 earth, is to settle immediately downward, and into the earth, incase 

 it meets with no obstruction. Water also has the power of dissolv- 

 ing a variety of substances and retaining the same in a soluble 

 state until it meets with some natural agent or artificial process 

 capable of extracting the same. The waters of rains and melting 

 snows, as they pass over the inclined surface of the earth, buoy up 

 and carry along to the adjacent streams the finest and most minutely 

 divided particles of soil, and which are the most fertile ; and as it 

 falls from the clouds, either as rain or snow, it absorbs fertility as 

 it passes through the air. Indeed, in whatever position we find it. 

 whether flowing in streams, or issuing from the recesses of the earth, 

 it contains an amount of fertility, either in solution or suspension, 

 or both. All soils possess the power of absorbing or retaining what- 

 ever fertile matter may be held in suspension or solution by water 

 as it passes through the soil ; and this fertility, too, is arrested and 

 retained very near the surface, and within reach of the roots of those 

 plants which are even the most shallow, like many of the grasses; 

 and as it is to the grass crop to which irrigation is principally ap- 

 plied, the most valuable varieties not only require a great amount 

 of moisture during the entire period of their growth, but sustain no 

 injury from a large surplus of water, when applied accordinrr to 

 the rules of hri^al'wn. and where the water is even so abundant 

 that the soil cannot absorb the whole, and a portion of it passes 

 along over the inclined surface in a broad sheet an inch thick, sur- 

 rounding the foot of each plant, it grows rapidly and luxuriantly; 

 but when the water is applied only by night to the growing crop, 

 and permitting the sun's rays and heated air to have full access to 

 the moistened surface through the day, as is practiced in some parts 



