136 transactions op the american institute. 



Compost Manures. 



Mr. R. L. Pell. — From the numerous changes that aro constantly taking" 

 place among- bodies in nature, and the new combinations that arc formed 

 in consequence of them, a great variety of substances are elaborated, and 

 prepared for the support of vegetable life. 



Some of the matters which they contribute possess volatility and fluidity, 

 such as water, and sundry gaseous materials, as hydrogen, oxygen, azote, 

 and carbonic acid gas in different states of combination. Heat, light, and 

 particularly electricity, are indispensably necessary to the well being of 

 plants. These are formed and applied in the soils on which the plants 

 grow, in greater or less proportions, according to the season of the year, 

 the nature of the climate, in regard to cold and heat, and the state or situ- 

 ation of the ground in respect to its quality; while others are more gross, 

 and require to be applied and incorporated with soils, or spread out upon 

 their surfaces, in order that they may produce their effects in promoting 

 vegetation. It is chiefly to these, as being the means of sustaining differ- 

 ent sorts of plants as crops, that the terra manure has been given by 

 practical writers on agriculture, though it is obvious that they must un- 

 dergo different changes, and be resolved into elementary principles, before 

 they can be taken up and contribute to the increase and support of vege- 

 tables. In the various materials which the art and industry of man have 

 rendered capable of being beneficially employed in this manure, there is 

 great diversity; some are found to yield the matters more readily than 

 others that are necessary for the support of plants, as animal, vegetable, 

 and all such substances as are rich in mucilage, saccharine matters and 

 calcareous earth, and readily afford carbon, phosphorous, and some of the 

 JBrial fluids that have been mentioned. While others are deficient of these 

 principles, or do not readily part with them, when employed as manures. 

 This is the reason why some substances when put upon ground, are so su- 

 perior to others, used at the same time, and in the same manner and pro- 

 portion, a circumstance which is often observed in the practical details of 

 husbandry. Some substances not only promote the growth of plants, but 

 likewise add to the quantity of vq^etable and other matters contained in 

 the soils on which they are distributed, and consequently provide for the 

 reception of the roots of plants, others operate upon the materials con- 

 tained in the roots of plants, breaking down their organization, and setting 

 at liberty volatile and other ingredients, by which new compounds are 

 formed and brought into such states as are the best adapted to the support 

 of vegetable life. Others again produce certain changes and alterations 

 in the texture of soils, such as rendering them more 0})en and porous, or 

 more compact and stiff, and 'thus fitting them to bear different vegetable 

 productions. And there are others that contribute in several of these 

 ways at the same time, hence manures may be divided into compound, ani- 

 mal, saline, vegetable and fossil. 



SOFT ANIMAL SUBSTANCES. 



There ai'e various matters of this nature that may be made very useful 

 in the compost heap for the purpose of improving land, some of wliich 

 have been but little attended to, except by a few farmers. Among these 



