Sir Humphrey Davy writes: "Some inquirers, adopting that sublime generalization of the ancient philosophers, that matter is the same in essence, and that the different substances considered as elements by chemists are merely different arrangements of the indestructible particles, have endeavored to prove that all the varieties of the principles found in plants may be formed from the substances in the atmosphere, and that vegetable life is a process in which bodies that the analytical philosopher is unable to change or to form, are constantly composed and decomposed. But the general result of experiments are very much opposed to the idea of the composition of the earths by plants from any of the elements found in the atmosphere, or in water, and there are various facts contradictory to the idea."

Some contend that the "ammonia of the air is sufficient to supply all the wants of the crops, and have maintained that any other supply of ammonia is unnecessary." Ammonia is one of the most valuable ingredients of manures. A certain class maintains that ammonia determines the value of manure. I think it the most desirable part of manure. It is well known that before nitrogen can become assimilated by plants it must be converted into ammonia. Nitrogen is exceedingly precious. It is the most costly element. Now, from the searching experiment of Dr. Laws, the fact is pretty clearly established that but little nitrogen is derived from the air, but almost entirely from the soil and fertilizers.

The exploded theory that artificial manuring is useless, that earth and atmosphere always contain and supply it sufficiently, must no longer beguile the agriculturist. I desire to consider manures. They are the main pillar of farming. They are a capital that never fails to produce a handsome dividend. Often, to dispense with them to save expense, is really to make expense. Land that has become much worn, if not well manured, becomes to a great degree, dead capital, and to cultivate it is a waste, in the sense that you are not getting out of it the value of labor, culture and seed. Manure, then, gathers infinite importance. There may come a condition of soil that nothing but manure will restore. Rotation of crops, fallow, trenching and deep plowing cannot fully or adequately bring it back into good "heart" or fine "tilth." These means only serve as a partial renovator. Prof. William Rhind, Mareschal College, Scotland, in his great work, " History of the Vegetable Kingdom," says : "Soils in a state of culture, though consisting originally of the due proportion of ingredients, may yet become exhausted of the principle of fertility by means of too frequent cropping, whether by repetition or rotation of the same, or of different crops.

In this case it should be the object of the phytologist, as well as of the practical cultivator, to ascertain by what means fertility is to be restored to an exhausted soil, or communicated to a new one. Even upon the plan of rotation, the soil becomes at length exhausted, and the cultivator obliged to have recourse to other means of restoring its fertility."

Draining and burning the soil are equally unavailable in renewing land. It may be well to mention the benefit accruing from burning. It is the decomposition of the vegetable substances contained in the turf, and subjected to the action of the fire, which dispenses part also of the superfluous moisture, but leaves a residue of ashes favorable to future vegetation. " But it often happens," says Rhind, "that the soil can no longer be ameliorated by any of the foregoing means, and in this case there must be a direct and actual application made to it of such substances as are fitted to restore its fertility. And hence the indispensable necessity of manures, which consist chiefly of animal and vegetable remains, that are buried and finally decomposed in the soil, from which they are afterwards absorbed by the root of the plant in a state of solution." It stands to reason that land cannot forever be drawn upon and not become sterile; that is, if nothing be furnished it to replace what has been extracted. This is exactly the principle involved in manuring. Says Morris Copeland, in " Country Life," " We know that any plant cultivated on an acre of land for many successive years without manure, finally reduces that acre to sterility. It will bear no more of its old crops.

The reason for this seems to be that the constituents of which that crop is composed are withdrawn to such an extent that there is not enough left to support new plants; not, enough, I mean, in a form adapted to the plants."

Now, if manures be absolutely necessary, what are they, and which is the best? There are many. First and foremost, the animal manures, fish, bones of animals, lime, gypsum, wood ashes, common salt, soot, peat earth, sea weeds, malt dust, rape cake and linseed cake, green succulent plants, and commercial fertilizers. I would call special attention to bran as a fertilizer. It is of great value. I would urge tillers of the soil to experiment with it on a small scale at first, to test the matter for themselves. The results will convince them. I have said that constant cropping without ever fertilizing, will ultimately render it worthless. Copeland states, "Take the best soil and cultivate it without manure. For many years the crops will be undiminished, but will ultimately decrease. The land is at first in what is called good heart; the balance is large and crops can draw on it to any extent without danger of check; but to ensure a continuance of this fertility, and to exactly carry out nature's laws, we must return to the soil as much of the constituents of the crops as they remove.

Unless we restore the elements we take from the soil in crops, we shall ultimately impoverish it."

Which is the best mauure? Sheep dung. In a fresh state it consists of water, 68.71; arotized matter, 23.16; saline matter, 8.13, in 100 parts. The 8.13 parts of saline matter is composed of phosphate of lime, magnesia, silicate of potash, common salt and silex. Says Copeland, "So powerful is this manure, that it is said that 1,000 sheep folded on an acre one day, would manure it sufficiently to feed 1,001 sheep, if their manure could all be saved; so that by this process, land which can the first year feed only 1,000 sheep, may the next year, by their droppings, feed 1,365. Spren-gle allows that the manure of 1,400 sheep for one day is equal to manuring highly one acre. In France it is allowed that one sheep manures about ten and a half square feet of land per night - when folded on the land. I dwell particularly on sheep excrement, for I am a great advocate for sheep grazing, for various reasons, not the least, their rich droppings. Horse manure is composed of water, 75.31; geine, or organic matter, 20,57; salts, 4.02, in 100 parts. The geine has carbon, 9.56; hydrogen, 1.26; oxygen, 9.31; nitrogen, 0.54. It is nearly double the geine of cow manure.

Cow manure, in 100 parts - Geine, 15.45; salts, 0.95; water, 83.60. Organic matter - Nitrogen, .505; carbon, .234; hydrogen, .824; oxygen, 4.818. 100 parts fresh cow dung afford five-eighths pounds nearly pure ammonia, or about two pounds two ounces carbonate of ammonia.

Experiments show that one cow prepares, daily, 85.57 lbs. dung. " Cow dung, for several reasons - its universality, its sameness of character, its composition - may be taken as the type of all manures, and all may be valued as they approach to or depart from it. A single cow, fed on hay and potatoes, will yield 31.025 lbs. dung. This would have lime enough for 140 bushels of rye, and its straw, could it all be evenly spread and readily taken up, and also more than enough nitrogen.'» Let me direct thought to the agricultural value of leached ashes (wood). In 100 bushels, Troy weight, analysis gives : Phosphoric acid, 11 1/2 lbs.; silex, 146 lbs.; oxide of iron, 17 lbs.; oxide of manganese, 51 lbs.; magnesia, no; carbonate of lime, 3.072 lbs.; potash combined with silica, 50 lbs. It is very desirable. Apply manure to surface, and also plow in deep. You thus meet all requirements.