_Bolivian Guano._--This as its name indicates, is from the coast of Bolivia, on the west side of South America. It was thought at one time to be fully equal in value to Peruvian, but some subsequent importations of almost worthless cargoes, have proved the deposit to be very variable in quality, or else purposely adulterated, which has had the effect to destroy confidence in all bearing that name. The belief of the writer is, that it was not adulterated, but owing to the fact that it is found in a latitude where it does sometimes rain, or where it is liable to be drenched by sea spray, that portions of it are injured in that way; so that a ship may have one portion of her cargo of the best kind, while the remainder is hardly worth the freight. The deposit is not large. _Chilian Guano._--The most of that imported into this country under this name, has been of a very inferior quality, and having been recommended by those interested in its sale, as having come from the same coast as that of Peru, and of equal value, and proving almost worthless, has deterred many from making another trial. Although there is a small supply of Chilian Guano, which is gathered from the rocks in pale yellow masses, some of which has been sent to England and this country, which is equal to any ever discovered in any part of the world, yet the great bulk of the deposit is so inferior that Chilian guano will never meet with universal favor. In fact, some of the stuff which has been sold under that name, is unworthy to be called guano. _Patagonian Guano._--Of this kind, larger quantities have been imported than any other beside Peruvian; and it has generally been sold at higher prices than its value as a fertilizer would warrant. Owing to the fact of its being deposited in a latitude of sunshine and showers, both of the utmost intensity; it never comprises the valuable qualities always found in that where rain never was known to fall. Besides the deterioration of the elements, samples of some cargoes of this guano have been found to contain upwards of 30 per cent of sand--in one case 38 per cent. It is said, however, that some of the deposits contain considerable quantities of crystalized salts of ammonia, magnesian phosphates, rich in ammonia, but which have been rejected by masters of vessels taking in cargoes, under the supposition of its being sea salt and calculated to injure the sale and value of the guano. It is believed that there is a a larger supply of this than any other guano, except Peruvian, but as no certain reliance can be placed upon its quality or value, it never will be extensively imported into the United States.