Mr. C. tried guano upon river bottom land, but the improvement was not so remarkable. We were assured by Mr. C., that many persons who had long been accustomed to look upon the hopeless barrenness of this land, were wont to stop as they rode past this field of clover, and look at it with utter astonishment. Some could not be satisfied with looking, but would drive to the house to inquire what magical power had been used to produce such a strange metamorphosis in the appearance of the place. When assured it was all effected by guano, they went away--not satisfied--but unbelieving. What tends much to increase the effect of this improvement, is the fact, that directly opposite lies another tract, still in its barren condition, lately purchased by Dr. Spence, a very enterprising gentleman, imbued with the spirit of improvement, which will soon be brought into the same condition, notwithstanding its unforbidding appearance. Mr. S. B. Atwell who owns an adjoining farm, has been equally successful in the use of guano. Before using it, his wheat upon 20 acres was hardly sufficient to pay for harvesting. The first crop after using it, 400 bushels. He has also increased the crop of corn from 20 to 260 barrels by lime, guano and clover. In the meantime, the land has increased in value in about the same ratio. In Lancaster County, we saw a field of wheat on the farm of Dr. Leland, sown upon corn ground, one part with 200 lbs. of Peruvian guano to the acre, the other with a full dressing of hog-pen manure, by the side of which the ground was seen in its natural barrenness, scarcely making a show of greenness; while the rank growth of the guanoed portion made as great a contrast with that manured upon the opposite side. Guanoed wheat upon the farm of Col. Downing in the same county showed as great a contrast with land both limed and manured; while directly alongside of this luxuriant growth, the land was as destitute of vegetation as a brick pavement. The effect of guano upon strawberries, Col. D. found to excel anything else ever tried. A neighbor of Col. Downing had a fine show for a wheat crop on exceedingly poor land from the application of only 90 lbs. Peruvian Guano to the acre. Capt Wm. Harding, Northumberland, C. H., assured us he made 27 bushels per acre upon only tolerably fair land, by the use of 200 lbs. Peruvian guano, plowed in and followed by clover, worth more than the guano cost. Col. Richard A. Claybrook, in the same neighborhood, made 15 bushels--the land along side almost as bare as the surface of the guano islands. We might mention a dozen others in the same place, in fact in most of the places mentioned, whose testimony would be as strong as those we have named.