In 1847, he used $100 worth of Patagonian upon same kind of land and reaped 330 bushels. In 1848, $200 worth of Patagonian and Chilian at $40 and $30 a ton, gave 540 bushels, which sold at $1 25, mostly for seed, on account of its superior quality. In each case the advantage to the land of equal value as to the crop. In 1849, he applied 10 tons Peruvian at $47, and 11 tons Patagonian at $30, upon 260 acres, from 75 to 250 lbs. to the acre. When we saw this crop the next spring, the appearance in favor of the Peruvian, was fully 50 per cent. upon the same cost of each kind per acre. In 1850 he applied 30 tons, of course, all Peruvian, with equal success to former years. Mr. Newton says, the second application of guano to the same land produces the best result--that notwithstanding the profit of the first application in the increased crop, the profit to the land is always greater. Before leaving Mr. Newton, we will place on record one expression highly creditable to him, and convincing in its palpable truth of the value put upon this fertilizer, by a gentlemen of sound judgment and candor of speech, equal to any other within the circle of our acquaintance. "I look upon the introduction of guano and the success attending its application to our barren lands, in the light of a special interposition of Divine Providence, to save the northern neck of Virginia from reverting entirely into its former state of wilderness and utter desolation. Until the discovery of guano--more valuable to us than the mines of California--I looked upon the possibility of renovating our soil, of ever bringing it up to a point capable of producing remunerating crops as utterly hopeless. Our up-lands were all worn out, and our bottom lands fast failing, and if it had not been for guano, to revive our last hope, a few years more and the whole country must have been deserted by all who desired to increase their own wealth, or advance the cause of civilization by a profitable cultivation of the earth." We are satisfied that the above opinion will be considered of more value--more conclusive in favor of guano, by all who are acquainted with the character of Willoughby Newton, than all else contained in the pages of this pamphlet. OTHER WITNESSES IN VIRGINIA IN FAVOR OF GUANO. As our principal object is to convince the skeptical, or induce unbelievers in its efficacy and value, to try experiments themselves by which they will be convinced and enriched, we offer the names of a few more gentlemen of high standing, who have been very fortunate in the use of this essential element of successful cultivation in Virginia, as witnesses, whose testimony ought to be, and will be, where they are known entirely conclusive.