CULTURE OF A FEW ORNAMENTAL PLANTS, 
179 
remains in the residue in combination with the acid employed, and may be detected 
by a little powdered lime, which separates the ammonia, and thus renders its pecu- 
liar pungent smell sensible. The sensation which is perceived upon moistening 
the hand with rain-water, so different from that produced by distilled water, and 
to which the term softness is vulgarly applied, is also due to the carbonate of 
ammonia contained in the former. 
" The ammonia which is removed from the atmosphere by rain and other causes 
is as constantly replaced by the putrefaction of animal and vegetable matters." — 
" It is worthy of observation that the ammonia contained in rain and snow-water 
possesses an offensive smell of perspiration and animal excrements, — a fact which 
leaves no doubt respecting its origin." 
We shall have occasion to say more of ammonia when we consider the products 
of vegetables ; it will suffice now to remark that nature has herein ''provided a 
corrector of what would, like atmospheric carbonic acid, become a deadly nuisance, 
and, by bringing down ammonia with the rain, converts it into a solvent of vegetable 
manure, fitted for laboration by the vital principle. 
This ammonia, and also the potassa in the loams, and other saline substances, are 
bond fide dissolved by water, and thus duly conveyed by the absorbents of the roots 
into the organism. 
Rain-water, when fresh, is known to be soft ; but it becomes rather hard in 
tanks lined with cement, probably by the abstraction of some of its ammonia — a 
defect which a very small portion of ammonia added to the water will immediately 
remedy. 
Common hard water from wells contains calcareous matter dissolved by an excess 
of carbonic acid. By exposure to air some of this acid escapes, carbonate of lime 
(chalk) is deposited, and the water is improved ; but for the purposes of horticul- 
ture nothing can be compared to the water derived from rain which flows through 
pastures into a pond that has a clay bottom. It is soft, replete with every soluble 
matter adapted to the nourishment of plants, and far preferable to any that can be 
obtained from artificial, confined depositaries. Possessing a natural fluid of so 
excellent a quality, the gardener will have no occasion to trouble himself with 
manure- water or any other offensive applications, the results of which, to say 
the best of them, are ever doubtful, and certainly, at times, very pernicious. 
CULTURE OF A FEW ORNAMENTAL PLANTS. 
In the desultory observations which we are now about to lay before our readers, 
two great principles will be found to be constantly regarded. First, no plant will 
be spoken of that is not really ornamental, and highly worthy of the cultivator's 
attention ; and next, the systems of treatment propounded will be those best 
