_Lasting effects of Guano._--Maj. Jones is well satisfied upon this point. In 1847, he used 16 tons, half Peruvian and half Patagonian, sowed with a lime-spreading machine and plowed in deep, say eight inches on clayey loam--planted corn and made 60 bushels per acre on 100 acres; which was an increase of 12 bushels per acre over any former year. Next spring the weeds grew as high as his head on horseback. Rolled them down and plowed under and sowed wheat, five pecks to the acre, and made a heavier crop than ever before made on same land, which he attributes entirely to the guano. Thinks the third crop of wheat is benefitted from guano plowed in three years previous. The extent to which guano is used in the State of Delaware may be inferred from the fact that it is not at all unusual for merchants in small country villages to purchase from 50 to 200 tons at a time for their retail trade. Among other successful users of guano in that State, we may mention Governor Ross, who, if as good a ruler as he is farmer, ought to be continued in office to the end of life. The soil to which guano has been mostly applied in this State is a sandy loam, and the process of applying it, by sowing broadcast from 200 to 350 lbs. per acre, and plowing in from four to six inches deep, previous to sowing wheat, which is always followed by clover, by every one who understands his own true interest; for wherever that course has been pursued, there has been a certain profit derived from the application, even when the wheat has failed. The improvements in farming in Delaware within the last ten years, will probably exceed in proportion to acres and people, any other State in the Union. Nearly all the northern part of the State has been whitened with lime, and the southern part is rapidly following the same path; while the sale of guano in all parts will exceed any other section of the country, if not in quantity, certainly in numbers of persons making use of this sure means of restoring the lands of an almost ruined State, to their pristine fertility. GUANO IN PENSYLVANIA.