OF AGRICULTURE. 205 



laws of life, but the laws of chemistry. The solids 

 and fluids of a living body escape part in air and gas, 

 leaving a solid mass differing equally from any living 

 organic product, and form inorganic elements. This 

 complexity and susceptibility to decomposition of 

 inorganic or vegetable bodies, is a great practical 

 fact in agriculture. It is this that forms the humus, 

 or vegetable mold, which imparts fertility to soil. 



The great practical lesson of all agricultural 

 experience teaches, that humus or mold, is essential 

 to the healthy growth of plants, and the perfection 

 of seed, that without humus, crops cannot be made. 

 So far as nourishment is derived from the soil, mold 

 or humus, with mineral salts, is the food of plants. 

 It may be laid down as a principle in agricultural 

 chemistry, that humus, in some form, is absolutely 

 essential to agriculture. 



HUMUS OR VEGETABLE MOLD. 



Humus, or mold, is the product of decomposition 

 of bodies once endowed with life. For the present 

 purpose, it may be considered as the result of 

 vegetable decomposition. Life, and the manner how 

 plants grow, may not be understood. Growth is a 

 process of life. Decay is a chemical process The 

 laws of decomposition are not only understood, but 

 its products ma.y be limited, controlled and hastened. 

 Decay is fermentation, and this, marked by its 

 several stages, ends in putrefaction. Putrefaction is 

 the silent onward march of decay. Its end is humus 

 or mold, the great promoter of fertility. 



The union of hydrogen and nitrogen, as before 

 said, forms ammonia. This ammonia, which always 



