_Want of Faith in the efficacy of guano._--Whatever doubts may have existed in the minds of careful men, there is no room for doubts now, that Peruvian guano possesses regenerating properties beyond belief, without evidence, and capacity to increase the productiveness of lands in sound condition, in such an eminent degree, that any farmer who has the power to obtain it, evinces great folly and perverse obstinacy, if he continue to cultivate his land without applying it; either for want of faith, or pretended disbelief in its efficacy; or because he thinks the price fixed upon it by the Peruvian Government, "unjustifiably high;" or because although he has no doubt it will answer in the moist climate of England, is sure it will never answer in this dry climate; or because he is afraid the luxuriant crops produced by the application of guano will exhaust his land; or because his neighbor Jones killed all his seed corn by putting only a handful in the hill; while Mrs. Jones killed all her flowers and fifty kinds of roses with the "pisen stuff;" and therefore he don't want any more to do with it; or because it has failed to give remuneration under the most injudicious application, made contrary to all instructions or experience of those who have used it; or for any and all the other thousand and one objections raised by those who have never used it, and seem determined they never will; probably because when the almost miraculous accounts of its operations were first published, they had cried out "humbug" so loudly they are determined no after evidence shall convince them the only humbug in the case was in their own disbelief. It is for the benefit of these unbelievers we are now writing. Our object is to present such an array of facts guaranteed by such respectable names, they shall have no hook to hang a doubt upon--no reason--no justifiable excuse for any sane man longer to neglect to apply an article of such positive, certain benefit to his hungry soil. ED. REYNOLDS ESQ., OF BALTIMORE, ON THE VALUE OF GUANO.