Col. Edward Tayloe of King George Co., having been very successful in the use of guano, induced his neighbor, Wm. Roy Mason, Esq. to test its powers by the most severe experiment we have ever known it subjected to. He selected a point of a hill, from which every particle of soil had been washed away, until nothing in the world would grow there. It would not produce, said he, a peck of wheat to the acre, but with a dressing of 300 lbs. African guano, it gave me thirteen bushels, and now while that is covered with clover, other, so called, rich parts of the field are almost bare. A field which had never produced for years, over four bushels of wheat to the acre, was dressed with 250 lbs. of guano and one bushel of plaster at a cost of $7 to the acre, which gave thirteen bushels of a quality greatly improved, and a very large growth of straw, which he esteems highly as a top dressing for the clover, which far exceeded upon the guanoed land that which was highly manured. The success of Mr. Mason was so flattering, he immediately purchased six tons for the next experiment. If all the faithless would pursue the course indicated in the following _experiment with guano_, by Mr. Richard Rouzee of Essex Co. Va., they would probably be as well convinced as he, that the greatest "humbugging" about guano, is in neglecting to profit by its use. He says:--"I must confess that I have been skeptical in relation to the various accounts of the fertilizing properties of guano, especially in these times of humbuggery, and therefore determined to subject it to the most rigid test." In view of this, on the 3d of October last, I selected two acres of land by actual measurement, proverbially poor, never having yielded in a course of ten years cultivation more than three bushels per acre, and in consequence, was called by way of derision, "Old Kentuck." To the two acres 560 lbs. of guano were applied in the most injudicious manner by strewing it on the top of the corn bed--the consequence was, when the wheat was ploughed in, and came up, a small girth was only seen on the top and a space between each row at least one third of its width; in this condition it remained until about the middle of November, when it had so sensibly disappeared, that it attracted the attention of one of my neighbors, who remarked to me, that at least one half of it had been destroyed, in which opinion I concurred; in examining that which remained, we were of opinion that three-fourths of it had from three to ten flies in the maggot state on each stalk; in this state of things I surrendered all hope of any tolerable return, more especially as the rust made its appearance in it a short time before it ripened.--Now for the result--