are washed with fresh supplies of water, in order that no extract may be allowed to remain.

By this means, the following products are obtained, viz. : the alcoholic tincture, holding in solution the essential oil, and also the ordinary decoction, dissolved or held in solution by water. These three distinct products may be united into one homogenous mass, in the following manner :

The alcoholic tincture and essential oil are placed in a suitable vessel, and subject to the action of a water bath, which must be furnished with a still head, and submitted to the process of distillation, in order to drive off the alcohol, which by this means is obtained perfectly colorless and limpid, and as such is the case, it proves that all the essential oil remains in the preparation or residuum, which is a brownish yellow resin, covered with a layer of yellowish liquor, some inches in depth, and composed of a watery extract. The aqueous decoction, to which is added the above watery extract, which floats on the surface of the resin, is then evaporated by an open fire, until it comes to the consistence of a syrup; it is then removed to the water bath and evaporated, until it becomes a nearly solid extract. This extract, which is about the color of chocolate, and of the agreeable bitter taste, the characteristic of hops, is mixed with the resin, which has been previously softened or melted, by means of the water bath.

By this method of preparing the hop, about 32 to 34 per cent. of extract is obtained from good hops; and all that the plant contains of those substances, necessary for the manufacture of beer, is drained out or otherwise obtained.

The humuline, when prepared in this manner, assumes the form of a nearly solid extract, of a blackish brown color, with a pungent smell, similar to the hop, the taste being, at first, bitter, and afterwards of an acrid taste.

In order to preserve the humuline, it must be softened or melted, by the application of heat, and poured into tin or earthen vessels, previously well dried. It must then be left to cool gradually, and a small quantity of alcohol poured on to the surface, just sufficient to cover it.

Upon allowing the alcohol to evaporate, the surface of

the humuline, in the vessel, will be covered with a thin coating or film, which, as long as it remains unbroken, will effectually prevent the humuline from becoming mouldy or otherwise injured, by exposure to the air.

When the humuline is required for the manufacture of beer, a sufficient quantity of the gummy extract is placed in an earthen vessel, and to every two pounds of the extract, about one pint and a half of hot water is added; the earthen vessel is then placed in a water-bath, in order to dissolve the gummy extract. The resinous extract is dissolved in a small quantity of alcohol, and when the two solutions are once quite limpid, they are mixed, and added to the wort, at any moment required.

The humuline is added to the beer, in about the following proportions:-Two pounds weight of humuline in place of six pounds weight of common hops.

If the two extracts are not previously mixed, the brewer may, at his discretion, mix them in any proportions that may be required.

A valuable extract is also obtained from hops, by placing them either in a pulverized or whole state, in a closed cylinder, and submitting them to the action of steam, either under considerable pressure, or at the mean pressure of the atmosphere, and, by the partial condensation of the steam which will take place, a liquid extract of hops is obtained; the watery particles of which may, if required, be evaporated to the same consistence as the humuline, and preserved in a similar manner.

The principle advantages resulting from the employment of humuline, are the following:-First, economy,—for by employing humuline, the brewer obtains from 15 to 20 per cent. more of the hop than when boiling the plant in the wort.

Another advantage, is the superior quality of beer which is produced. The next advantage, is the practicability of the brewer availing himself of a good crop of hops, as he may buy a large quantity, when they are good, and the market is overstocked, and, by reducing them to humuline, he is enabled to keep them any length of time, without

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being liable to spoil, as is the case when the plant is kept longer than a year.

A further advantage consists in the small space which the essence or useful qualities of this plant occupies, thus rendering it eligible for sea voyages, in which it would be extremely useful for making beer, and as a remedy against scurvy.

The patentee claims the methods above described, of making or producing a concentrated extract of hops.-[Inrolled in the Petty Bag Office, August, 1841.]

Specification drawn by Messrs. Newton and Son.

TO ROBERT WARINGTON, of South Lambeth, in the county of Surrey, Gent., for improvements in the operation of tanning.-[Sealed 16th March, 1841.]

THE first improvement consists in preparing hides or skins for unhairing, by soaking them in a solution of the carboate of potash or soda, composed of from one to two pounds of the carbonate to ten gallons of water.

The second improvement consists also in preparing hides or skins for unhairing, and at the same time swelling them; or in swelling them only, by immersing them in solutions of the three following kinds of articles, viz.: first, baryta, potash, and soda; second, all the acids, except sulphuric acid; third, vine cuttings, sorrel, culinary rhubarb, and such like vegetable matters.

The solutions the patentee prefers to use, are, of the first kind, a solution of soda, composed of from half a pound to a pound of dry carbonate of soda, dissolved in ten gallons of water, which has been previously rendered caustic, by the addition of half its weight of fresh burnt lime; of the second kind,—a solution of muriatic acid, composed of from half a pound to two pounds of the acid, of specific gravity 1.17, to ten gallons of water; and of the third kind, a mixture of from one to ten pounds of bruised culinary rhubarb, and one gallon of water.

The third improvement relates to graining hides and skins, and consists in using, for that purpose, a solution, composed of from half a pound to four pounds of carbonate of ammonia, and ten gallons of water.

The fourth improvement is for the purpose of preventing oxidation, and consists in mixing, with the tanning agent, small quantities of those vegetable matters and chemical agents, that are capable of retarding oxidation, such as bruised culinary rhubarb, bruised potatoes, &c., and gum, starch, &c.

The fifth improvement consists in preventing the putrifaction of hides, skins, or other animal substances, by immersing them in a solution of bichromate of potash, or of sulphuric acid; the former consisting of from one-eighth of a pound to half a pound of the bichromate to one hundred gallons of water, and the latter of from a quarter of a pound to a pound of sulphuric acid to ten gallons of water.

The patentee claims, Firstly.-The use of carbonates of soda or potash, for soaking the hides or skins, so as to render the hair capable of being easily removed.

Secondly. The employment of baryta, potash, soda, all the acids, except sulphuric; and also vegetable matters, such as culinary rhubarb, sorrel, apple marc, &c.; for the purpose of facilitating the removal of the hair, and at the same time swelling the hide or skin, or for swelling them only.

Thirdly. The use of the carbonates of ammonia, as a grainer, for the purpose of graining hides or skins.

Fourthly. The employment of vegetable matters and chemical agents, capable of retarding oxidation, such matters or agents being used with the tanning agent employed.

Fifthly. The use of bichromate of potash, in solution, or diluted sulphuric acid, for preserving skins or other animal substances.- [Inrolled in the Inrolment Office, September, 1841.]

TO WILLIAM EDWARD NEWTON, of the Office for Patents, 66, Chancery-lane, civil engineer, for certain improvements in the manufacture of fuel,-being a communication.-[Sealed 7th July, 1841.]

THIS new combustible, called by the inventor, "carboleine," is chiefly composed of two combustibles, namely, pulverized coal and vegetable or animal oil.

There are various modes of manufacturing this carboleine, according to the purposes for which it is required, either for steam-engines, smithies, foundries, glass-houses, or for heating common stoves, chimnies, and kitchen ranges, in dwelling-houses.

If a combustible is required, capable of giving out a very considerable heat, (and the cost is a matter of inferior consideration,) the carboleine will be best made from coals, coke, and brown coals, together with some animal or vegetable oil and fluid tar. If, on the contrary, the chief object is to have a combustible which, in proportion to its efficacy in heating, shall be cheaper than other materials hitherto used for that purpose, it will be necessary to make the carboleine from peat coals, mixed with oil of tar, or some bitumen. The proportion or quantities of coals and oil, to be mixed together, is to be regulated by the purpose for which the carboleine is intended, and must depend upon the greater or less degree of heat required for such purpose. In order to manufacture a good carboleine, proceed as follows:

First. Take such a quantity, as may be convenient, of coal, charcoal, coke, brown coals, or peat coals,-reduce them to powder, by means of a grinding or stamping mill, and afterwards pass the pulverized material through several sieves, to render the powder as fine as possible. Put this coal powder into wooden tubes, and let it there be mixed with the animal or vegetable oil.

In order to avoid the expensive use of hydraulic or mechanical presses, to obtain a compact mass out of this mixture of powder and oil, and also, in order to concentrate