DRAINAGE. 133 



iron grating, or heavy wire netting, fine enough to prevent the entrance of reptiles or other 

 animals. One outlet to an area of from ten to fifteen acres is usually considered a good 

 arrangement. 



A uniform grade is very desirable, for if any portion of the main be lower than the 

 outlet, there will, of course, be a permanent stoppage, as the water will stand there until 

 there is a deposit of mud, and it will not be forced out by the action of the water. All 

 curves and angles should be avoided, if possible, as they are the places where obstructions 

 will be liable to occur. 



Depth of Drains* The best English authorities advise that the drains should not be 

 less than four feet in depth, and that even a greater depth may be desirable; it depends mainly 

 upon the subsoil; but they are often made very serviceable at a less depth. Sometimes a 

 seam of gravel or other porous material, charged with water, may be found underlying a con 

 siderable portion of the ground at a greater depth than four feet, and this may render it 

 necessary to dig the drain sufficiently deep to reach that seam. When such, or similar cases 

 occur, it is desirable to have the drains quite deep, as they will perform more efficient service 

 in draining the whole area under which this strata extends, than shallow ones placed nearer 

 together. It has been proved by experiment that drains three feet deep, at forty feet apart, 

 are not so effective as those at five feet deep and fifty feet apart. The depth necessary to lay 

 the tiles will depend much upon the character of the soil and subsoil. As a general rule, it will 

 cost as much to dig the fourth foot as the other three, and if the conditions are such that the 

 benefits arising from the greater depth will more than counterbalance the increased expense, 

 it will be advisable to increase to the fourth or even fifth foot in depth. The farmer must 

 take into consideration the various conditions of soil, and be his own judge in this 

 respect. Many writers advocate three feet, and some even two and a half feet, as sufficient 

 for all practical purposes in most soils; but we prefer, as a general rule, that the depth be four 

 feet. Prof. Shattuck expresses the following opinion in the Drainage Journal : 



&quot;They must be deep enough to be out of the way of frost; they must give sufficient 

 room for the roots of plants above the water-table, because of the evil effects of stagnant 

 water and the intrusion of roots; deep enough to prevent evaporation of the water arising in 

 the soil from the force of attraction, or at least to reduce it to a small amount. Experiments 

 show that capillary attraction operates with considerable power at eighteen inches. They 

 have also shown that water coming from a thirty-inch drain is two or three degrees colder 

 than that taken from a depth of four feet, and that this is a little cooler than that from a 

 greater depth. &quot;We must draw the conclusion that evaporation has considerable effect at 

 thirty inches. Four feet, then, seems to be the standard minimum depth; it cannot always 

 be had, but better go deeper than not so deep, when possible. 



The above statement is mainly in reference to the requirements of the crop to be grown. 

 I admit that depth and distance between drains should bear a relation to each other, that the 

 character of the soil and subsoil is an important factor in the question. I give the above 

 as a general guide. There is a feeling with many that thirty inches, or three feet in depth, 

 is sufficient. I know that drains at those depths will do good service, but I believe one at 

 four feet will, as a rule, do better. Theory indicates this and practice confirms it. 



Of two drains at different depths, the deeper one acts first, and with far more effect; but 

 the greater expense is objected to, though without sufficient reason in many cases, it seems to 

 me. The tiles cost the same in either case, and, from my standpoint, the additional labor of 

 the deeper one is of little account to the general farmer. I venture to say that the 

 majority of Western farmers are unemployed one-half of the time during three or more 

 months of the year, and at that season when the work of drainage could go on with the 

 least interruption to farm culture. 



The labor of the farmer is an important part of his capital, and with proper management 



