Mr. Rhind, page 109, takes exception to my answer to "A. H'.'s" inquiry for an effectual remedy for the destruction of thrip. Probably Mr. Rhind took my remarks, under the sense which the Editor points out as dangerous. If so, I quite agree with him, that anyone using sulphur in such a manner would be sure to come to grief. But in all my experience with it (yet I am open to conviction and invite criticism) I have never known it to be in any way injurious to vegetation, when applied to hot-water pipes. In regard to its efficiency for destroying thrip, I can only say, that I have annually kept large ranges of graperies, clear of both thrip and red spider, through the persistent use of sulphur, applied to the hot-water pipes as described in my answer to "A. H." But let me not be understood to mean, that one application is going to keep the grapery clear of thrip, for the entire season, for it will not, no more than one fumigation is going to keep a rose-house clear of green fly. It is easier to keep an army at bay than to turn it out after it has taken possession. So, my motto always is, to keep such enemies at bay, never let them get a firm footing. In this lies the secret, if secret there be, of successfully contending with the numerous insects which attack hot-house plants in general.

Anyone with experience, knows how much easier it is to keep a house clear of green fly than it is to get rid of it after it has gained a footing there. I have always found a well balanced atmosphere, in regard to heat, moisture, and air, a powerful agent against the encroach of thrip and red spider.

Mr. Rhind's plan of cleaning off the rough bark and painting with such a mixture as he describes, is excellent; in fact, all well-kept graperies should undergo such an operation annually. I do not wish to discourage Mr. R., but perhaps I may be allowed to state, that I know of a grapery 60 feet long "lean-to" with a 25-foot rafter, in the centre of which is a single vine of the variety known as White Tokay and filling the whole house. This was planted in the year 1783, and has, I believe, undergone the operation of barking and painting annually ever since; and yet it was in this same grapery that the writer was first impressed with the efficacy of sulphur "vapor" as an antidote for thrip.

South Virginia, April 8th, 1886.