150 On preserving Plants from Snails and Slugs, 
The best method I can propose for the erection of hot-houses, is, 
to have the rafters and the piers in front, (if any are wanted) of cast- 
metal ; the sash-frames of the best oak, which shoukl be perfectly dry, 
and have been felled at least two years; and the ribs of wrought-iron. 
Houses erected in this manner, will stand much longer than they 
generally do in the regular way of building 
The houses I have the care of, have been erected twelve years, and 
no one can see that the metal ones are at all the woise for wear, but 
the wood ones are in some places fractured. 
I remain, Gentlemen, 
Yours, &c. 
Worcester, Jug.Uth, 1831. J. CuR. 
Article IV. — On Presermng Plants from Snails, Slugs, 
8fc. by means of the ''^Bygrave Plant-Preserver.'''' By 
A Practical Gardener. 
Gentlemen, 
Numerous are the modes practised with a view to the 
extirpation of those pests of the garden, — slugs and snails, and for 
preserving plants from their ravages. But we nevertheless find that 
all the means hitherto adopted, or recommended for this pui-pose, are 
far from ,being as successful as could be desired. 
No doubt, ne^\ly burnt lime reduced to powder, and dusted through 
a coarse cloth o\qv dug land, in the dusk of the evening, will kill any 
of these cre^itures that come in immediate contact with it ; but vast 
numbers ^vill escape, by being under ground, or accidentally protected 
by leaves or any other covering ; and besides, the effect of the lime is 
not lasting, for the slightest shower, or heavy dews, or even being 
exposed to the air, deprives it of its caustic and destructive proper- 
ties. Watering with lime-water, is also liable to fail, from the same 
causes, and is, besides, if incautiously used, apt to injure, and some- 
times altogether desti-oy, vegetation. Sir Humphrey Davy, in his 
Elements of Agricidtural Chemistry, (page 317) says, "Quicklime, 
in its pure state, whether in powder, or dissolved in A\'ater, is injurious 
to plants. I have, in several instances, killed grass by watering with 
lime-water. ' 
Sifted coal-ashes, from an iron-foimdry, smithy, or gasometer, 
sti'ewed over the parterre, are of use for the time, because they abound 
in minute sharp particles, which the slug or siuiil cannot crawl o^er. 
