exacted, if the trader prove the deficiency not to have been occasioned by fraud, either practised or intended.

The liberty of warehousing spirits without payment of duty, which the act permits, is a great indulgence and accommodation, as it gives the trader the use of the money till a market offers, or till it suits his own convenience. At storing, the strength must be either 11 or 25 per cent. over proof, and the casks cannot be of less content than 100 gallons each; but by Sec. 10 of the 6th and 7th Wm. IV. c. 72., a distiller is now permitted to store casks so low as 20 gallons. A rent is required at the rate of one penny per week for every 40 gallons when placed in warehouses belonging to the crown; but, by a subsequent regulation, traders have the privilege of relieving themselves from this rent by storing the spirits on their own premises, under the look and key of the revenue. It has been suggested that it would be advantageous to the revenue, were all the spirits manufactured throughout the empire, stored in the warehouses of the crown and delivered from thence for either home or foreign consumption. By this means, no spirits could leave the distillery without the knowledge of the officer, unless by incurring a palpable risk, which, it is presumed, no respectable trader would attempt..

Spirits may be sent from Ireland to England, on payment of the difference of duties, which is 58. 2d. per gallon; the duty in Ireland being 2s. 4d., and in England 7s. 6d. With regard to Scotland, the duty there is 3s. 4d., which nearly amounts to an interdiction of intercourse between Ireland and that country. In England, distillation may be said to be a monopoly, since it is still confined to a few capitalists, while in Scotland and Ireland it is open to every speculatist. The mode of charging the duty is, however, much the same in all parts of the empire, being regulated by the saccharometer and hydrometer, under the survey of officers. The former instrument having been already described, it only remains to give an account of the latter.

The hydrometer, as its name imports, (from 'vdwę, water, and μstgov, a measure) is a test of the density, or gravity of water. This instrument is constructed on the principle that all bodies weigh in proportion to the quantity of gravitating matters they contain, and is merely a ready substitute for the hydrostatic balance, to which it is preferred, on account of the ease and expedition with which it can be used; for this reason it has been adopted by government to ascertain the strength of spirituous liquors. To illustrate the general principle, let water be the standard of comparison, a cubic inch of which, at 60° of Fahrenheit, weighs 1000 ounces; and since, as has been

already stated, all bodies weigh in proportion to their particles of gravitating materials, and that gold is more minute, simple, and cohesive than any other body, if it be adulterated with any other metal, its specific gravity, or comparative weight, must be less in proportion to the quantity of alloy with which it may be amalgamated. The weight, therefore, of gold is a sure criterion of its quality, and by experience the purity, or impurity of substances, whether solid or fluid, may be obtained. Besides, when it is said that the specific gravity of proof spirits is 923, the meaning is, that a cubic foot of the liquor will weigh exactly 923 ounces; and if the specific gravity of alcohol be reckoned as 825, it implies that a cubic foot of alcohol will weigh 825 ounces, avoirdupois. The relation which all other spirits has to this standard, or proof, is expressed by saying that they are so much above, or under proof; so when it is said, that a spirit is 25 per cent. above proof, it implies that 100 gallons of it will admit of 25 gallons to reduce it to the strength of proof; and if it be 25 per cent. under proof, it is considered to contain 25 gallons of water more than is contained in 100 gallons of proof spirits: in other words, proof spirits are a mixture of an equal quantity of water and alcohol. Hence a table might be easily formed to shew what quantity of water, or spirits, should be added to any given portion of spirits to render it true proof. From this explanation, it will be seen that the calculations made from any instrument are simple and easy of comprehension ; but, for the practical application, recourse must be had to the instructions accompanying the instrument, and explanatory of the tables and sliding-rule constructed for computing the strength of spirits at different temperatures.

The following general rule may be adopted for calculating the strength of spirits, whether above or below proof, viz. :--To reduce the strength to hydrometer proof, divide the quantity by its degrees of strength, whether over or under hydrometer proof. When over proof, add the quotient to the quantity; if under proof, subtract it therefrom, which gives the quantity at hydrometer proof.

A simple method of ascertaining the specific gravity, and consequent commercial value of Ether, Spirits, Sulphuric, and other acids, &c., was recommended for twenty-five years by Sir James Murray, M. D. of Dublin, part of whose plan has been since adopted by Mr. Gilpin. I subjoin a representation of it which was given to me by Sir James, in 1823, when my former work was in

the press.

The adoption of this principle would be important to country purchasers, who are often imposed upon when forcing and deleterious ingredients are mixed in spirits, to make them produce a head, or appear strong. An economical hydrometer can thus be furnished, which, avoiding thermometric calculations, may be understood, and used by any person.

By this plan, the spirit to be examined is brought to the one constant and uniform temperature for experiment; this is easily effected by placing a bottle of the liquor, during a few minutes, in a basin of tepid water. To those who are not supplied with a thermometer, a simple one can be supplied by an artist at a trifling expense, having a single mark engraved on it, say at 65°, to which every sample of spirit can be readily brought, and examined in a room of nearly the same temperature.

Sir James Murray has observed that where the balance is accurate and the stem, or tube, of the flask is small, a difference of a half, or even a quarter of a degree, will be apparent on the scale engraved on its neck. Half a pint, or a pint, has been the usual quantity tried. The vessel is a light, thin flask, attached to the end of a beam by a small ring of brass, fixed round the part of the stem at P, and engraved proof.

A is the flask, or regulator, having the degrees of the scale cut on its neck. B denotes the weight attached to the opposite end of the beam, and filed, or ground down, until it exactly counterpoises the flask containing real proof marked P.

Now, it is plain, that if the sample for trial be stronger than real proof, by which the instrument was first adjusted, it will consequently be lighter, and in order to counterpoise the weight B, more of the liquor must be added until the scale is balanced. The height at which the liquor stands in the stem is then to be noted, and every line, or mark, tells the number of degrees, above proof, that the spirit

amounts to.

If, however, the sample be weaker than true proof, in that case less bulk will make the same weight, and every degree under the proof-mark, P, shews the result as so many degrees under proof. By these means, therefore, the different liquors are tested by a single weight, and the inconvenience and trouble of using a variety are rendered unnecessary.

Sir James Murray also recommended another method on the same principle which is very simple, (Fig. 2.)

An accurate lever, or steel-yard, is furnished with a solid glass weight, B, at one end, say 20 or 30 ounces' weight; this is filed, or ground away until it counterpoises a flask A, of true proof spirit at 65°, accurately and completely filled up to a ground stopper-this flask is suspended by a wire, ring, or hook, in a notch cut in the beam at C, which is there marked proof.

Now, it is plain, that if the same flask be filled with weaker spirits at 65°, it will weigh more, and it must then be moved forward by the ring, or wire, on the arm of the steel-yard, or lever, until it is poised; and the number at which this occurs denotes the degrees of strength, below-proof. But if the sample be stronger than true proof, then the same vessel will not hold a similar weight, and the ring and flask must be drawn nearer to the extremity of the lever; and the line where it balances, indicates the degree, above proof, without the slightest trouble or inconvenience.

This, therefore, is very superior to the thousand grain bottle, because no weights, nor further calculations, are requisite. The operose small deductions or additions of Dicas and others are avoided, so that a common porter can, in a moment, use the proposed instrument.

Sir James Murray has found that proper glass rods terminating in solid glass balls for weights, are the most suitable beams, or levers. When well poised on glass balls or pivots, they are neat and accurate, and are not liable to vary, like metallic substances, from damp, friction, or oxydation.

The thermometer, (Fig. 3.) having only a single line, or degree, (65) is cheap, simple, and effectual.

Of hydrometers there are various sorts made of different materials, but Dr. Blagden is of opinion that those made of glass are the most accurate. Glass hydrometers are so subject to accidents, that metal ones have been preferred. Sykes's instrument is the one in general use, and was adopted by the act of 56 Geo. III. chap. 140, and subsequently confirmed by the 58th Geo. III. chap. 28. This hydrometer consists of a hollow ball one inch and an half in diameter, having a flat stem 3. 4 inches long, divided on both sides into ten equal parts, and each division is subdivided into five equal parts. At the other end is a small conical stem 1. 13 inches in length, having a pearshaped bulb at its extremity. The whole instrument, which is made of brass, is 6. 7 inches long, and is accompanied with nine circular weights, numbered 10, 20, 30, 40, 50, 60, 70, 80, 90, and an additional one of a solid rectangular form, with a notch in each to fit them to the stem. The square weight is made for the summit, and the others for the conical part at the under portion of the ball. By the separate application of these weights in succession, the range of strength between pure water and alcohol is determined. Each weight is equivalent to ten principal divisions. The weight numbered 60 indicates proof at the temperature of 51° of Fahrenheit; and by the addition of the square on the top, it sinks it to the same point in distilled water of the same temperature. This square weight being just one-twelfth part of the entire weight of the whole hydrometer, together with its bottom weight, marked 60, causes the scale to shew the difference between water and proof spirit, which, the act of parliament states, must weigh of an equal bulk of distilled water. Before the invention of this instrument, much fraud was practised on the public, as there was no accurate method of enabling purchasers of spirits to detect the deceptions of unfair dealers.

The following anecdote, being in point, is worthy of preservation: A shopkeeper at Canton, sold to the purser of a ship, a quantity of distilled spirits according to a sample shewn ; but, not standing in awe of conscience, he, afterwards, in the privacy of his store-house, added a certain quantity of water to each cask. The spirit having been delivered on board, and tried by the hydrometer, was discovered