No. 3. General Principles and Directions for Irrigation. 



95 



of the crop. This, however, can only apply 

 to pure water. The application of turbid 

 water, where a considerable amount of mud 

 and earthy matters is held in suspension, or 

 the application of sewerage water to a grow- 

 ing crop, would be liable to the same objec- 

 tions as inundation. I am referring, as must 

 be obvious, to fields in grass, to which irri- 

 gation is applied; and not to fields under 

 arable culture, to which it may be, but to 

 which I have never seen it applied. What 

 are called catch-meadows, is a form of irri- 

 gation upon side hills, where the water, 

 after passing over a certain poition of the 

 land, is caught in a trench, and again used 

 for the irrigation of other portions of land. 

 In a plan of irrigation, the first thing to be 

 considered is the command of an adequate 

 supply of water, and this, of course, at a 

 level above the land to be irrigated. This 

 may be obtained from a brook, whose course 

 may be turned, or a portion of whose waters 

 may be diverted for that purpose ; or, as it 

 is here sometimes obtained, by the collec- 

 tion of the water of springs bursting out 

 upon the high lands into a common recepta- 

 cle or reservoir, which may be tapped for 

 the purpose of letting out the water, as it 

 maybe required. I recollect at Canterbury, 

 in New Hampshire, at the establi.'^Lment of 

 the United Brethren — certainly among the 

 best farmers in the world — that these indus- 

 trious people, for the sake of establishing a 

 mill power, much needed among them, had, 

 by an embankment or dam between two 

 high clay hills, formed a large basin or res- 

 ervoir, which the melting of the snows in 

 the spring, the rains, and some springs on 

 the sides of these hills, would completely 

 fill with water, furnishing a supply for the 

 season ; and which, passing into successive 

 basins as it descended the hill, was used five 

 times for mill purposes; such us a flouring 

 mill, a threshing mill, a mill for sawing 

 wood, a mill for grinding bark, and a mill 

 for the dressing of leather. I could not 

 help admiring the ingenuity of these people 

 in creating a mill power where none existed 

 before; and it is perfectly plain that, by such 

 an arrangement, they might have executed 

 an extensive system of irrigation, had it 

 been thought proper so to apply the water. 

 In some situations, where fuel and labour 

 are not expensive, steam power might be 

 employed with advantage to force water and 

 to form a reservoir at the height necessary 

 for irrigating the land below. On a farm in 

 Dedham, Massachusetts, situated upon an 

 acclivity, at the foot of which ran a small 

 brook, I saw that the farmer had formed a 

 reservoir above his house and barn. Into 

 this reservoir, through leaden pipes of a 



small bore, the water of the brook was 

 forced up, by means of an hydraulic ram 

 and forcing pump, itself operated by the 

 running brook; and a supply of water was 

 always maintained in the reservoir amply 

 sufficient for the domestic purposes of the 

 family, and the supply of the cattle in the 

 yard. The water was forced a considerable 

 distance, and the expense of the machinery 

 was very trifling. The cost and labour of 

 keeping it in operation were nothing, ex- 

 cepting that of opening and shutting the 

 gate. The expense of the whole apparatus, 

 excepting the reservoir, did not exceed five 

 pounds, or twenty-five dollars. The farm 

 would, in England, be considered a very 

 small one, not exceeding one hundred acres; 

 but it shows, just as much as a larger one, 

 to what advantage the most simple contriv- 

 ances may be applied. This water, thus 

 raised, might have been used for the pur- 

 poses of irrigation. 



Where the supply of water is sufficient, 

 it is carried along on the upper margin of 

 the land to be drained in a trench or furrow ; 

 and when it is required to throw the water 

 over the land, the end of this trench or fur- 

 row is to be stopped, either by a gate or a 

 damming up for the occasion, so that the 

 water entering it may flow gently and 

 evenly over its sides. It is plain that the 

 water trench or furrow should be carried 

 nearly upon a level ; first, that the flowing 

 of the water over the sides of the furrow or 

 utter may be equal and uniform; and next, 

 because any variation from a level would 

 force the water to a particular point, cither 

 to prevent its equal diffusion over the field, 

 or to occasion, perhaps, a rupture of the side 

 of the trench, and an injury to the field 

 itself. The variation from a level, recom- 

 mended by some persons with a view to 

 giving the water an easy flow in the trench 

 or gutter, is only one inch fall in every ten 

 feet. 



Besides the formation of the trench or 

 furrow, the surface to be irrigated requires 

 to be made even, the knolls reduced, the 

 hollow places filled, and the holes, occa- 

 sioned by vermin of any kind, stopped, that 

 the water may flow evenly over the whole. 

 The degree of inclination desirable in a 

 field to be irrigated, is stated to be about 

 ten feet in ninety; but although this may be 

 found desirable, it is obvious that it cannot 

 be under the control of the farmer to any 

 considerable extent, but at a very great ex- 

 pense. We must take the land as we find 

 it ; for few things are more costly than at- 

 tempts materially, or to any great extent, 

 to alter its shape. It would be prejudicial 

 ■to undertake to irrigate our lands without 



