In Hindostan and China all the land on the coast is regularly treated with sea water, and they depend solely on this management for the increase and good ness of their rice crops. In Poland salt is extensively used in the tillage of land.
Many valuable communications on the use of salt, as a manure, have been made to the British Board of Ag riculture. I may be allowed to mention two further experiments made on this subject.
To show the effects and advantages of salt properly applied to vegetables, the gardener of Lord R. Man ners made the following experiment, in an extreme dry summer, upon a bare piece of pasture land, out of which the cattle were all taken for want of grass. He marked off four places, each of which was watered for nine successive nights, in the following manner: the first with one gallon oispring water; the second with a gallon of the same water, containing an ounce of common salt; the third with the same quantity of water, and two ounces of salt; and the fourth with the same quantity of water, and three ounces of salt, which gave the following effects: The grass ,in the second place grew more abundant, and of a darker green than that in the first; in the third place it grew only by spots, for part of it was killed where the greatest quantity of water fell; and the fourth was quite brown for a greater compass than the third: by which it appears that an ounce of salt in a gallon of water had a better effect than the water alone; and that three ounces of salt mixed in a gallon of water was more than the grass could immediately receive; but the fourth place, in the ensuing spring, was the most fertile of them all.
The other experiment I shall notice is related by Dr. Holland, well known by his agricultural survey of Cheshire.
After draining a piece of sour rushy ground about the middle of October, he ordered some refuse salt to be spread upon a part of the land, at the rate of eight bushels to the acre, and in another part sixteen bushels. In a short time the vegetation disappeared totally, and during the month of April following not a blade of grass was to be seen. In the latter end of the month of May a most flourishing crop of rich grass made its appearance on that part where the eight bushels had been laid. In the month of July the other portion pro duced a still stronger crop; the cattle were remarka bly fond of it; and during the whole of the ensuing winter, (which is ten or twelve years since,) and to this clay, the land retained, and yet exhibits, a superior verdure to the neighbouring closes.
In the memoirs of the Royal Academy of Sciences at Paris are several papers showing the great advanta ges resulting from the use of salt as a manure, in im proving land, and increasing the number of cattle. It is there asserted that more than the usual quantity of working cattle on a farm gives a double advantage, by doing the work in season, and enriching more land by their additional manure. The difficulty of maintain ing this additional number of cattle without increasing the expense, is obviated by the use of salt. To prove which it is advanced : 1. That salt given with the food of cattle augments its nourishment.
2. That in proportion to the quantity of salt eaten by cattle, the effects of the augmentation are perceived.
3. That no ill consequences follow its use, even when given without stint.
These propositions are supported by unquestionable evidence, and the trials of very many persons.
Crau, in the jurisdiction of Arles, in the county of Provence, France, has an extent of six leagues by three, the whole surface of which is covered with small rough stones, and not a tree or bush is to be seen upon the whole district, except a very few scattered on the bor der; yet on this apparently barren spot, by the free use of salt, more numerous flocks of sheep are bred and reared than upon any other common of equal extent in the kingdom; and what is not less remarkable, the sheep are healthier, hardier, and endure the severity of the winter with less loss, though they have fewer sheep cotes for covering, than those fed and bred in more luxuriant pastures, and that have the advantage of convenient shelter. Add to this, that the wool of the flocks bred and brought up in the Crau is not only the finest, but bears the highest price of any in France. It is concluded, that these surprising effects arc con sequent upon the unlimited use of salt: for it frequent ly happens that the Crau is so parched up in sum mer, that the animals are obliged to turn up the very stones to get the few blades of grass that grow round them, and yet none perish for want of food. Allowing every excellence than can possibly be supposed inher ent in the herbage, yet the quantity of it is so small, that without the abundant use of salt, a fourth part of the sheep kept in the Crau could not subsist on it.