516 Science of Farming. 
or pearl-ash; or, to place it in another point of view, in sending 
72 lbs. of pearl-ash, 22 lbs. of it is carbonic acid. The pearl-ash 
is there taken to the distillery, and a current of dry carbonic acid 
gas is made to pass through it, where another definite portion of 
the acid is made to combine with it, and the 70 lbs. of pearl-ash 
comes out 92 lbs. of salaeratus; that is, 22 lbs. more of this gas 
is fixed in the pearl-ash. At the distilleries, this gas is disen- 
gaged in large quantity, from the molasses and water, while fer- 
menting, preparatory to its being distilled into spirit. Now, can 
any one tell precisely how this 44 lbs. of dry gas got combined 
with 56 lbs. of lime, so as to form 100 lbs. of marble? Or, how 
44 lbs. of carbonic acid entered into combination with 48 lbs. of 
caustic potash, to make 92 lbs. of salaeratus? Whether any one 
can tell the " how and the wherefore" of this, it matters not. 
We know the fact, and we know further, that provision has been 
wisely made to keep up an equilibrium, or a constant quantity of 
the several components of the atmosphere. The diffusibility of 
gases regulates this. So, too, the " supply and demand " of car- 
bonic acid has been provided for by Infinite Wisdom. Every 
cord of wood that is burned, restores to the atmosphere just suffi- 
cient carbon to grow another cord of wood. 
Whether this burning is effected by the rapid combustion of 
fire in a steam engine, or the more tardy combustion, by the rot- 
ting process, ultimately it amounts to the same thing, and there is 
not an animal that breathes, nor a fire that burns, nor a particle 
of animal or vegetable matter that perishes unburied upon the 
earth, that does not yield to the atmosphere certain gases. We 
see them rise in the smoke from a fire, in the steam from a dung- 
heap, and from our own breath in frosty weather. Where do 
they go? Are they lost? No; there is no such word as lost, in 
the whole vocabulary of nature. Is the steam or vapor that rises 
from a vessel of boiling water lost? No; it rises into the atmo- 
sphere till it meets a colder stratum of air, and is condensed into 
water, and again gently descends to the earth, and hangs upon 
every leaflet and every blade of grass, in drops of pearly dew, or 
in larger masses falls in the rain, hail or snow. So, too, the 
gases arising from the combustion, putrefaction or decomposition 
of animal or vegetable matters, are, in the economy of nature, 
through the agency of vegetable life, again w^orked up into wood, 
hay, grain, roots, flesh, tallow, &c., &c. 
But however abundant the organic food of plants may exist in 
the " free air of heaven" — however largely they may abound in 
simple mould or soil," or in the rains and snows that fall from the 
clouds — they will avail the indolent or ignorant farmer but little, 
if he neglects to supply to his soil, if it is deficient in them, the 
equally important mineral or inorganic constituents of plants; for 
without these in a soil, from which the skeleton or boney frame- 
