The Press. MONDAY, DECEMBER 11, 1871.

Press, Volume XVIII, Issue 2688, 11 December 1871, Page 2

The Press. MONDAY, DECEMBER 11, 1871.

It will be remembered tbat during tbe last session of tbe Provincial Council, tbe question was discussed of the practicability of adopting.some method of irrigating certain portions of tbe Canterbury plains by artificial means ; and many are at the present time strongly in favor of such an undertaking. To those who are anxious to see this design carried out, it is particularly interesting to note the degrees of success attending contemporaneous efforts in tbe same direction in other parts of the world, and much information thus acquired could be used by them to practical advantage, especially" wbere the natural features of the country offer conditions corressponding in any particulars to those of our own plains. It would, however, be next to useless, excepting perhaps for a definition of certain general principles, to make anything like a minute investigation into the gigantic systems of irrigation in many parts of Europe and elsewhere, from the simple fact that the means at our disposal are totally inadequate to their adoption. It would even be beyond our present purpose to dwell At any length upon the various

works of this description that have been introduced in the United States, though as one instance we may remark that the complete transformation that tbe Mormons have effected by such means is without doubt one of the marvels of the age, where tbe desert has literally been converted into one of the most luxuriant districts in tlie world. Our business is rather with works of less pretensions ; and in more recently populated countries ; and iv looking nearer home, it appears that in certain parts of Queensland, New S.iuth Wales, and Victoria, examples of irrigation by artificial means are not infrequent, and in every instance with which we are at all acquainted they have been attended with more or less satisfactory results. For instance, at a recent meeting of the Ballarat Farmers' Club, Mr Thomas Bath in relating his experiences stated that for the last four years be had used the water of Lake Learmouth during the summer months for purposes of irrigation. He irrigated about five hundred acres of land, and laid them down in English grasses. He found it took him about half a million gallons of water per acre for the season. This was equal to a layer of water of about twenty-two inches over the whole, surface of tbe land irrigated, so that a discharge of one cubic foot of water per second was sufficient to irrigate 166 acres. A million gallons of water formed a cube of a little over fifty-four feet, and this would irrigate two acres for the Bummer. He limited the season for irrigation to 155 days in the year; and during this time the land required thoroughly saturating once in about every fourteen days, and each watering involved a layer of two inches of water over the whole surface. Nothing was gained by waiting a longer period than fourteen days, as tbe laud would require more water ; and if the land got too dry the grass would be checked. In cases of rain, the irrigation was delayed accordingly. The plan he adopted was the "catch-work" system, as it todk less water, and was laid out to receive the water with less expense than the bed-work. The water was brought on the land through a main conductor, having a fall of about twenty inches to the mile. He commenced to irrigate at the upper side of the land, where the water was turned into feeders, and these being shallow and level when full, the water flowed down over the grass in one thin uniform sheet. The water was brought on in great force, and kept within a small compass; because in trying to irrigate too much ground at the same time it took more water, as the water had time to get down too deep in the land. As one piece of land got watered, he let the whole of the water on to tbe next piece of land below, and so worked hia way to the bottom of the land to be watered; by this means very little water was wasted. He found that irrigation greatly increased the grazing capabilities of the soil; the richer the land the greater the gain. He found that irrigation eradicated sorrel, as the grass and clover grew so thick that it was completely smothered. In cutting main conductors he found that from 18 to 24 inches was enough fall to the mile; and when on the land to be irrigated the conductor was madd broad and shallow, as grass would grow on the bottom and sides, and the water when wanted could be turned easily into the subraains. At each confluence the conductor was fitted wit'a stops, which turned the water either way at pleasure. All the stops were of the same length, two going across the broad or main conductors, and one stopping the narrow or submains. All the stops were Bet in order while the ground was damp, so that the grooved pieces were driven easily into their places. The submains were at right angles with the main conductor, and the feeders parallel with it, and laid in perfectly level; not often straight, but curved according to the contour of the country. He stated that tbe feeders should be laid down with great care: if hollows were allowed, the water would lodge there and perish the grass, but if properly done they would lead off all the water, and surface-drain the land for the winter. Stagnant water proved ruination to irrigated lands. He found the plough and the scoop the best and cheapest instruments to use for making the conductors and feeders. He recommended that irrigation should be commenced early in the summer, or whenever the ground was getting dry and hard, but it should not be continued too late in the autumn, as the land should be allowed to get thoroughly dry before winter. He was of opinion that irrigation would not pay for the lifting of water by machinery except in the vicinity of cities or towns, where sewage water could be used. To irrigate to advantage, he maintained that the water must come on by its own gravitation. One objection to artificial irrigation on the Canterbury plains has been raised, because, as they are composed of one vast shingle bed, it is therefore contended that the water supplied would filter through the top soil before any appreciable results would eventuate, at all commensurate with tbe time, trouble, and expense incurred. But as a direct refutation of this view, we have been informed .that artificial irrigation upon the Canterbury Plains has already been attempted: ft is true upon a somewhat minute sc/_ile, but sufficient to demonstrate clf.arly that the amount of silt brought o'j and spread abroad with the water rendered the top soil comparatively impervious, and enabled it adequately to sustain the fertilising influences tbat the moisture distributed.