MANUFACTURE OF AMMONIACAL SALTS AND MANURES.—E. Pettitt, of Kingsland, patentee. This invention relates to a new method of making ammoniacal salts from certain animal matters, also the manufacture of manure.— The inventor takes one hundred pounds of fish, and places them in a leaden trunk, and adds about five pounds weight of sulphuric acid diluted. This mixture is allowed to stand, (being occasionally stirred,) until it assumes a homogeneous past' consistence— sometimes heat is applied to facilitate this operation. The acid liquid or pickle, after it has been in contact with the animal matter for a sufficient length of time, is drawn off and pressed out of the fish. This acid liquor is next evaporated almost to dryness to extract the sulphate of ammonia therefrom, in the form of crystal, which may then be purified in the usual way. To obtain the muriate of ammonia, lime is added to the pasty mixture produced as aforesaid, or the acid liquor drawn from it, distilled at a great heat nearly to dryness, passing the products ot distillation through a solution of muriatic acid, or muriate of iron; the muriate of ammonia may then be evaporated in the usual way by crystallization. Instead of making the sulphats or muriate of ammonia, the inventor takes the fishy and acid mass, and submits them to artificial heat. The fish may then be first ground up and then submitted to about 3 per cent, by weight of sulphuric or muriatic acid. The 100 lbs of fish is only an example to show the proportion of acids employed. Some kinds of fish are better than others. This manure may be mixed with swamp muck, charcoal, or superphosphate of lime. This method ot making manure is different from that described on page 211, this Vol., Scientific American, and appears to be the same in principle exactly, as that for which a patent was granted to Dr. R. Hare, of Philadelphia, about two years ago. TREATING THE FLEECES OF SHEEP.—Geo. Stuart, of Glasgow, N. B. This invention consists in using a new compound,! for the protection of the fleeces of sheep in order to render wool free from moisture, and to add warmth and comfort to the animal, also to render the wool better adapted for manufacturing purposes. The old composition which was used for this purpose was a mixture of butter and tar, the new composition is simply rosin oil or colophon, in which is mixed a quantity of solid rosin. This mixture is heated up and applied to the fleece of the animal until it is uniformly coated. Our farmers would certainly look twice before they would expend the amount of money required to obtain a patent for simply treating the flocks of sheep with rosin oil. The above are condensed from the " London Repertory of Inventions" for May, in which we see two patents granted for covering substances with vulcanized india rubber, one patent was for covering wires, and the other for sheathing ships. In Amer'ca patents are denied tor the mere application of old substances to new purposes ; in England patents are granted, and justly too, for such new applications. It has been too much the policy of our Patent Office to find out arguments and reasons to reject applications for patents, to the great hindrance of progress in the arts. We hope a more liberal policy will now be exhibited.