The deoomposition of manuro is duo, as a rale, fo the classes or ferments, the active ferraeut on the outside of tho heap, rr wbere the air ciroulatesireely, and the flow ferment in the interior of the heap, or where tho supply of air is limited. The regnlation of the fwo kinds of fermentation is necessary to the suoecssful rotting of manure. H the heap is too loosely built, the deeomposition is too rapid. Ou tho other hand, if the manure is too firmly paoked, the decomposition naay bo too slow, and the mannre wi'l not bcomo sufflciently disintegrated to produce tho best effect in thii soil. A powerful nioans of controllins; fermentatiou is tho supply of moisture. Tho addition of water lowers the ture, and thus retareis fornientation. French authorities maintain that the principal precautions necessary to preveit loases of ammonia consist simply in regularly and properly watering the manure with the loachingF. In case of drought, if the leachings are insufficient, the lack shonld be made upwith water. The neod of keeping manure moist is especially marked in case of horse manure, which is naturally dry and decoinposes with great rapidity. The same is trut) in a less degree of sheep manure. The comruon and harmful "flre fanging" is the result of an insuffloient supply of water and mny bereaclily checked by sprinkling. Tho sprinkling, however, shonld bc rcgularly dono and the heap kopt in a constant state of moistnre; otherwise the altérnate wetting and drying wi)l rasnlt in a loss of amnionia. Preservation of manure in this manner is generally practiccd in Europo, and the product obtained is highly esteemod as a fertilizer. It is very dark colored, or even black, and acquires a highly offensive odor, while the straw in it loses its consistency and becomes soft and incoherent. This black substance is held by certain French agriculturists to possess special valué as a plant food. A method employed in the preparation of this well rotted manure in Franoe is as iollows: The manure is placed, on slightly inclined plats of packed earth or cement, so arranged that the leachings drain out into a pit from which they are pumped up and distributed over the manure beap. It is usual to provide two manure plats so arranged that when one is full (when the manure is eight to ten f eet high) it may be allowed to ferment nndisturbed while the other is used. The manure is carried from the stables to the top of the mannre heap inwheelbarrows over an inclined plane of boards. Care is also taken to smooth down the sides of the heap to prevent the too free access of air and the loss of leachings. It has been questioned whether the construction of expensive cisterns for collecting the mauuro leachings repays the cost, but it is obviously desirable from what has been said regarding the value of the liquid manure and the desirability of promoting regular and uniform fermentatiou of the manure that the leachings should be saved and added to the manure heap by some means. Stored separately, the liquid part rapidly deteriorates, and the solid part, from lack of moistnro, is liable to undergo "fire fanging, " or harmful fermentation. Professor W. H. Beal, in The Farmers' Bulletin, from which the fore going is an extract, saya that experimenta have indicated that 131 degrees F. is the most favorable temperature for manure fermentations.