MESSRS. A. B. ALLEN &. Co.--Dear Sir:--Having promised that I would furnish you with the result of my application of the 21 tons of guano which I purchased of you last winter, I proceed now to do so, and give you full liberty to quote my experience in favor of the use of that most invaluable manure, to all who are anxious to profit by the experience of others without incurring any risk of their own. My object, and it should be that of every one who has used guano, is to extend the knowledge of its great value to any owner of poor soil, like the worn out plantations of North Carolina. I applied 20 tons of this guano as a top dressing to a field of 200 acres, which had been seeded in wheat under most unfavorable circumstances. At the time of application, so unpromising was the appearance of the growing wheat, that my manager and myself thought it almost a waste of money and labor to try this experiment,(1) but as the rest of my crop did not require any manure, I resolved to see what would be the effect. I am confident the field would not have averaged, without the top dressing, seven bushels per acre--it yielded rather over 13 bushels, besides securing to me a full setting of clover.(2) My mode of application was as follows; to each 200 lbs of guano I added two bushels of ashes and a bushel of plaster mixed intimately, and then sown broadcast, at the rate of six and a half bushels per acre, harrowed in with a light harrow. This application was made in March, and the early part of April, and in less than three weeks after the application, the wheat had undergone an entire change, from a yellow, sickly color, to a dark luxuriant green. The application had evidently infused new life and vigor into the plants, and as the result proved, very nearly or quite doubled its product. So much for the crop of wheat; but what was still more valuable to me, in my system of farming, it likewise secured for me a full crop of clover, which would certainly have failed but for this application. I also applied one ton of this guano mixed in the same way, to a small field of oats. I plowed this under with a small plow, together with the oats; the result was equally gratifying. My chief object in this last experiment, was to secure me a small field of clover, near my stables, and in this I fully succeeded; which I feel assured I should not have done but for the guano. My brother and myself have made various experiments of late years, with guano, and concur in the testimony of all those who have tested its value, carefully and judiciously, in pronouncing it to be the most expeditious renovater of the soil within the farmer's reach; and exclusive of the farm yard, the most economical of all manures. In proof of my conviction of its value