60 
GARDENING AS A SCIENCE. 
and previously strained through white blotting paper. The clear liquid will 
speedily become turbid ; and as each drop of potash falls into it, it will there 
deposit a portion of a substance perfectly white in itself, though often discoloured 
by some iron, which the acid has also taken up. The white sediment is chalk, 
(carbonate of lime,) — i.e. chalk. So far the subject of earths, — of loam in 
particular, has been noticed generally, because it is our first object to elucidate the 
cause of those failures and disappointments which amateurs experience in attempt- 
ing to emulate the practice of experienced gardeners. In the next place, we desire 
to impress the fact, that loams so vary in their natural components, as to defy 
imitation ; and we therefore caution our experimental readers against the danger 
of following too strictly the indications of pure chemistry. 
When a loam is formed by the natural action of the elements, producing the 
crumbling to pieces of certain rocks ; all the constituents become blended, and 
interspersed by a process which man, by his puny machinery, cannot imitate ; 
hence the attempt to add ammonia, soda, potash, &c., to loams exhausted or 
deficient of those saline matters may prove highly injurious. In Nature's laboratory, 
the process of interblending has been the work of countless ages ; man's attempts 
are the triflings of a few hours — they cannot even be deemed imitations. 
We recur then to grass-turf, as our best representative of pure and well-con- 
cocted loam, and will close this article, by an allusion to two modes of preparation, 
which are excellent and feasible ; the first method, indeed, now to be described, 
comes under our ready inspection. 
A neighbouring gentleman is a strenuous admirer of a great variety of stove- 
plants, (none strictly requiring heath-soil,) and he is wonderfully successful, by the 
use solely of a compost consisting of about three parts grass-turf, two parts stable- 
dung, and one part sharp, gritty, or river sand. These are thrown together, 
turned and chopped repeatedly, till they be reduced to a homogeneous fibrous mass, 
— two or more years old. The soil is not pressed tightly into the pots, but by fre- 
quent copious syringings it is daily washed among the roots. This treatment, with a 
heat of 60° to 70°, produces a most luxuriant vegetation, and the Cacti., Musacece 
OrchidacecE, EuphorhicB^ AmaryllidacecB., thrive surprisingly. 
By the following process, turf can be reduced speedily, and in a great degree 
rendered clear from the larv88 of insects. It is strongly recommended by a name- 
less writer, in a very able paper upon soils. Collect the turf, chopped to small 
pieces : lay it on a deep bed of warm stable-manure in a heap, a yard every 
way ; then surround it on all sides with hot dung, sufficient to form a strong hot- 
bed ; and this may be done economically, at the time of constructing that bed for 
cucumbers or melons. By the time that the crop is off, or even in six weeks, if 
the heap be made independently of forcing — the grass turf will be reduced, insects 
destroyed by the heat, and the mould so mellowed and enriched by the vapours of 
the dung, as to require only the spade to render it fit for use. The surrounding 
manure is, of course, to be previously removed. 
