We learn by that excellent monthly periodical, " The / merican Farmer," (Baltimore) that guno is doing wonders for some poo: lands. One case is related of the Hon. Jamei PeaTce, who first applied guano in 1845, at th( r?e of 550 lbs. to the acre of very poor land It was applied as a top dressing mixed wit! plaster, for a crop of wheat; the wheat was doubled in quantity, and fine clover succeedec it, and the effects were apparent in two othej crops afterwards. There are many differenl opinions among our farmers respecting the value of guano as a manure. Some assert, that it does not produce results of a satisfactory character, according to its price, and thai " it is all worn out in the first crop." Guano, like all other manures of an animal character, should be plowed into the soil, or laid in the hills or rows of crops that are planted and not sown. It is perhaps the best general manure in the world, and there are good and bad kinds of it, and farmers should know this. Johnston states, that of two kinds examined by him, taken from one box one contained eight per cent, of sand, and the other only two per cent. Some kinds of guano only contain seven per cent of ammonia, while other parcels contain 25 per cent. Dr. Ure gives the lol-iowing as the average result of his analyses )f g Auine guano. Organic matter capable of ifForaing eight to seventeen per cent, of am-nonia in the soil, fifty per cent.; water eleven; phosphate of lime, twenty-five; phosphate of magnesia, thirteen; sandy matter, one Der cent—making the one hundred parts. But irery little guano is as rich as this in organic natter containing* nitrogen. In the produc-ion of turnips, it has been found that land, op-dressed with guano, at the rate ot 3 cwt. )er acre, produced 23 tons 8 cwt. of Swedish ;urnips (ruta baga), while 20 tons of farm-yard nanure, to the acre, only produced 18 tons 11 ;wt. of turnips. An acre of land lor potatoes vas dressed with 3 cwt.of guano, and it yielded .8 tons 9 cwt. of potatoes; this was near Pais-ey, Scotland. An acre of wheat dressed with )ne cwt. of guano, yielded 48 bushels; and 3 ;wt. of guano to the acre produced 64 bushels )f barley. This is related on the authority of loi. Johnston. There can be no doubt of the jood qualities of guano as a manure, and on )oor soil, or soil worn out by successive crops without manuring, some powerful fertilizer nust be employed to redeem the soil from )arrenness to fertility; guano appears to be he manure best adapted for this, but, at the lame time it is best tor farmers in the iiterior )f our country, to conduct their system on the principle of making their own fertilizers, and )btaining them at as low a cost as possible, rhe nitrate of soda or nitrate of potash (saltpetre) , ground along with charcoal, makes a nost excellent compound, to be applied for op- dressing, along with an equal quantity of ground plaster; this can be obtained in many )laces of our country where guano cannot.