An allusion to the above-named article, by yourself, or one of your contributors, in the April number of your Magazine, has induced me to solicit a small space in one of your next issues, to add my mite of testimony to its merits.

For some time past I have observed in the Gardener's Chronicle and other English gardening periodicals, numerous and various attestations of its potency in annihilating the numberless entomological pests with which gardeners have to contend; consequently, as soon as I discovered that it was in the market here, I purchased a box of it of Mr. Alfred Bridgeman, and took it home to experiment with. After reading the directions, which accompany the box, I concluded I

I would commence, as it is said the majority of the most successful business men who have reached the top round of the ladder have commenced, viz., by beginning the ascent at the bottom round first.

Acting on this principle, I took the smallest quantity recommended, viz., 2 oz. to 1 gallon of water, or, which is the same thing, I weighed 3 oz. of the compound, and put it into a pail with 6 quarts of soft water: after remaining there for 6 or 8 hours, it was thoroughly dissolved and fit for use.

I then looked around for a favorable, or, rather, an unfavorable subject to experiment upon. I soon found a Bourbon Queen rose, with the lower leaves thickly peppered with red spider, and the young growth at the top as thickly covered with mildew and green fly. I must admit that this is not a very creditable confession for a gardener to make, but assuredly this was the precise condition in which I found her majesty the Queen of the Bourbons, whom 1 politely escorted and introduced to the new element," Gishurst's Compound," and then and there gave her a good sousing over head and shoulders for ten or fifteen seconds. Rather rough usage for a Queen, I admit, but more humane than decapitation, after all. I replaced her on her throne; and the next day, in medico-professional style, paid my patient a visit, when I found her as free from her enemies as were the Israelites of old after crossing the Red Sea.

The green fly was perfectly black, the mildew had disappeared, and the spider, if not quite defunct, was in a perfect state of quiescence. I may as well remark here, however, that in about a week the spider made his appearance again; for that reason I would suggest that it would be advisable to make the solution a little stronger for that gentleman, say 3 oz. to the gallon; but for the green fly and mildew, 2 oz. are sufficient, as I have repeatedly tried it on Roses, Pelargoniums, etc. As regards mealy bug and scale, I can not speak experimentally, as, fortunately, I have very few to experiment upon, but these I am satisfied it will destroy by applying from 6 to 8 oz. per gallon of water.

This compound will be found an excellent substitute for sulphur in vineries: instead of scattering sulphur broadcast over floor, leaves, pipes, and flues, (which is very unsightly,) take 2 gallons of this mixture, if mildew appears, and just draw the syringe over the affected foliage, and there will be an end of it. If it appear again, in a week or two, "repeat the dose," as the disciples of Galen say.

And now, Mr. Editor, what think you of some of our pomological enthusiasts investing five dollars in this article to give it a fair trial on that merciless rascal, the plum curculio? My impression is, that two good applications of it, at the right time, would, as Mr. Toodles says, "squelch him".

In this city and Brooklyn conservatories attached to the dwelling are becoming very numerous, and the gardeners, I know, often have trouble in obtaining permission of the ladies of the mansion to " smoke the greenhouse," in consequence of the disagreeable smell which pervades the whole house whenever this operation has to be performed; and frequently, when it is considered necessary to smoke, especially in the early part of the winter, there are, in fact, but few plants that require it, and yet the whole house must be filled with smoke to get rid of them.

When this is the case, dissolve 4 oz. of the compound in 2 gallons of water, and dip the plants in it, as I described in my No. 1 trial; and by following this up, this tobacco smoke nuisance may be at least partially dispensed with. The liquid, I find, will keep good and fresh for three or four weeks.

[We are obliged to W. for this lively description of his experiments with Gishurst's Compound. There is no person more competent to make such experiments, and none whose testimony may be more implicitly relied upon. We have no doubt the "Queen" will ever hereafter consider him a most faithful and loving subject for having so summarily disposed of her enemies. The suggestion in regard to the "little Turk" is a good one. He has no business here, and ought to be driven from this continent at least. Who will go a "V " on the "Turk?" In the mean time, W., let us hear from you again. - En].