Four sorts of vinegar are prepared, all of which are perfectly limpid, which do not, like the common, contain any tartar, malic acid, resinous or extractive matter, nor indeed any mineral acid, lime, copper, or other substances. The simple vinegar marks--2° hydrometer for salts, at 12° centigrade thermo. it is stronger tasted than common vinegar, and produces a disagreeable irritation. The aromatic vinegar is prepared with tarragon, the smell is agreeable, but it has the same fault as the former. The vinous vinegar is formed by adding some alcohol to simple vinegar; it has a very sensible odour of acetic ether; the alcohol softens the flavour in some degree, but the vinegar is still very sharp. The acid, called strong vinegar, is in fact a very good acetic acid at 10-1/2° hydr., it is very white, clear, and sharp, without the usual burnt flavour, and seems to form the basis of the preceding kinds. It can be sold for 8 or 9 francs (7s.) per lb. which is only half the price of that distilled from verdigris. Although not so agreeable to the taste as common vinegar, these new kinds are more elegant to the eye, and do not mother. The editor of the Retrospect makes the following observations: The proprietors of this manufactory seem to be perfectly aware of all the several productions which could be prepared from the refuse of their principal object; and we have no doubt but that the substances they procure in this manner will amply compensate them for the use of the capital that must be invested in building the furnaces. The nature of the vessels in which they distil the wood is not mentioned, but they are probably cast iron retorts, or vessels of a similar nature, in which a distillation _per latus_ takes place. The application, therefore, of lord Dundonald's furnaces for procuring coke to this purpose would be still more advantageous. A cubic yard of wood yields 100 quarts of acid liquor, besides 50 or 60 lbs. of thick oil. The method of making charcoal of a _uniform quality_, for which a Mr. Kurtz has taken out a patent, is the following: A sheet-iron chest, which has a cover that fits it tight, and a pipe, or tube, that descends nearly to the bottom, and coming out from its side above, is fixed in brick work. In this the billets of wood are put. Fire is then made underneath. It is obvious, that the wood is kept at one temperature from its being immersed in vapour, as the vapour cannot escape at the top, but must descend to the bottom, and then proceed up the pipe, by which it is conveyed away. The effect is, that the charring process goes on regularly, and the wood is charred equally. The carbonization is finished when the vapour ceases to appear, and nothing but carburetted hydrogen gas escapes. The charring of bones is performed in iron cylinders, furnished with tubes to receive, and convey away, the impure ammonia.