Hav.— Lime as a Manure. 207 
compost together, of which a part is usually soluble in water. By this 
kind of operation lime renders matter which was before comparatively inert, 
nutritive; and as charcoal and oxygen abound in all vegetable matters, it 
becomes at the same time converted into carbonate of lime. Marls, and 
and chalk have no action of this kind on vegetable matter. They des- 
iroy worms and other tender-skinned vermin, and they prevent the too 
rapid decomposition of substances already dissolved, but in other respects 
their operations are different from that of quick lime. Lime marls, and 
even shell sand produce wonderful effects on peat soils by absorbing the 
gallic acid which they contain, and promoting the decomposition of the 
woody matters. 
All soils having a deficiency of calcareous earth, and which do not 
effervesce with acids, are improved by lime, either mild or quick lime. 
Sandy soils are improved more than clay. When a soil deficient in calea- 
reous matter contains much soluble vegetable matter, the application of 
quick lime should always be avoided, as it either tends to decompose the 
soluble matters, by uniting to them carbon and oxygen so as to become 
mild lime, or it combines with the soluble matters and forms compounds 
having less attraction for water than the pure vegetable substance. The 
case is the same with regard to most animal manures, but the operation is 
different in different cases, and depends upon the nature of the animal 
matter. Lime forms a kind of insoluble soap with oily matters, and then 
gradually decomposes them by separating from them oxygen and carbon. 
It combines likewise with the animal acids, and probably assists their 
decomposition by abstracting earbonaceous matter from them, combined 
with oxygen, and consequently it must render them less nutritive. Ittends 
to diminish likewise the nutritive powers of albumen from the same causes, 
and always destroys to a certain extent the efficacy of animal manures, 
either by combining with certain of their elements, or giving them new 
arrangements. Lime should never be applied with animal manures unless 
they are too rich, or for the purpose of preventing noxious effluvia. It is 
injurious when mixed with common dung, and tends to render the ex- 
tractive matter insoluble; and with almost all soft animal or vegetable 
substances lime forms insoluble composts, and thus destroys their fermen- 
tive qualities. Such compounds, however, exposed to the continual action 
of the air, alter in course of time: the lime becomes a carbonate, and the 
animal and vegetable matter enter by degrees into new compounds suited 
for vegetable nourishment. In this viewlime presents two great advantages 
for the nutrition of plants: the first, that of disposing certain insoluble 
bodies to form soluble compounds; the second, that of prolonging the 
action and nutritive qualities of substances beyond the time during which 
