VOL, LXXX.] PHILOSOPHICAL TRANSACTIONS. 687 



weight, the sum of the two showing the true specific gravity. The weights 

 should unquestionably be made to apply on the top of the stem, so as never to 

 come into coiitact with the liquor; and in using the hydrometer, its stem should 

 always be pressed down lower than the point at which it will ultimately rest, that 

 by being wetted it may occasion no resistance to the fluid. The instrument itself 

 should be of as regular a shape, and with as few inequalities and protuberances, 

 as possible, that all unnecessary obstruction to its motions may be avoided. 



As it is not probable but disputes will sometimes arise, it would be advisable, 

 that some of the principal excise offices should be provided with a good pair of 

 scales, and a weighing-bottle properly marked, the quantity of whose contents 

 of distilled water at 6o° had been previously determined. By filling this bottle 

 up to the mark with the spirit in question, and dividing its increase of weight by 

 the given weight of water required to fill it, the specific gravity of the spirit might 

 be better ascertained, even under the management of a common operator, than 

 by the most dexterous use of the hydrometer. 



The simplest and most equitable method of levying the duty on spirituous 

 liquors would be, to consider rectified spirit as the true and only excisable matter. 

 On this principle, all such liquors would pay exactly according to the quantity of 

 rectified spirit they contain ; so that when a cask, for instance, of any spirits 

 was presented to the revenue officer, his business would be to determine from 

 the quantity, specific gravity, and temperature, of the liquor, how many gallons, 

 or pounds, of rectified spirit enter into its composition; each of which gallons, 

 or pounds, should be charged a certain sum. The complicated regulations at- 

 tending the adaption of the duties to different degrees of strength would thus be 

 avoided; and it is believed that many frauds might be prevented, which artful 

 persons have now an opportunity of practising, by altering the strength of their 

 spirit in a variety of ways. From the tables already recommended, it would be 

 easy to deduce this quantity of rectified spirit, either by weight or measure, in 

 any given quantity of a spirituous liquor; or other tables might be constructed 

 which should show it at once by inspection. 



If however it be thought by government most expedient not to make any esseib- 

 tial change in the present manner of collecting this article of the revenue. Dr. 

 B. would at least recommend, that the specific gravity should be substituted for 

 the relation to proof spirit. Thus, instead of ordering so much duty per gallon 

 to be paid by spirits ] to 6 under prooC it may be enacted, that the same sum 

 shall be paid by spirit of .9335 specific gravity, or, not to be too precise, by 

 spirit from .93O to -935, and so on for any other degrees of strength; a certain 

 temperature, suppose 6o°, being always understood to be meant when specific 

 gravity is mentioned in an Act of Parliament. The duties to be laid according 

 to either of these methods may readily be adjusted or equalized to those paid at 



