| 90 | .980386 | 27.2 | .980510 | 26.7 | | 90B | .980376 | 27.2 | .980500 | 26.7 | | 91 | .982371 | 23.9 | .982496 | 23.6 | | 92 | .984374 | 20.8 | .984498 | 20.5 | | 93 | .986385 | 17.7 | .986510 | 17.4 | | 94 | .988404 | 14.8 | .988529 | 14.5 | | 95 | .990431 | 12.0 | .990557 | 11.7 | | 96 | .992468 | 9.3 | .992593 | 9.0 | | 97 | .994512 | 6.7 | .994637 | 6.5 | | 98 | .996565 | 4.1 | .996691 | 4.0 | | 99 | .998626 | 1.8 | .998752 | 1.6 | | 100 |1.000696 | 0.0 |1.000822 | 0.0 | +------------+---------+--------+---------+--------+ In the above table for Sikes's hydrometer two densities are given corresponding to each of the degrees 20, 30, 40, 50, 60, 70, 80 and 90, indicating that the successive weights belonging to the particular instrument for which the table has been calculated do not quite agree. The discrepancy, however, does not produce any sensible error in the strength of the corresponding spirit. A table which indicates the weight per gallon of spirituous liquors for every degree of Sikes's hydrometer is printed in 23 and 24 Vict. c. 114, schedule B. This table differs slightly from that given above, which has been abridged from the table given in Keene's _Handbook of Hydrometry_, apparently on account of the equal divisions on Sikes's scale having been taken as corresponding to equal increments of density. Sikes's hydrometer was established for the purpose of collecting the revenue of the United Kingdom by Act of Parliament, 56 Geo. III. c. 140, by which it was enacted that "all spirits shall be deemed and taken to be of the degree of strength which the said hydrometers called Sikes's hydrometers shall, upon trial by any officer or officers of the customs or excise, denote such spirits to be." This act came into force on January 5, 1817, and was to have remained in force until August 1, 1818, but was repealed by 58 Geo. III. c. 28, which established Sikes's hydrometer on a permanent footing. By 3 and 4 Will. IV. c. 52, § 123, it was further enacted that the same instruments and methods should be employed in determining the duty upon imported spirits as should in virtue of any Act of Parliament be employed in the determination of the duty upon spirits distilled at home. It is the practice of the officers of the inland revenue to adjust Sikes's hydrometer at 62° F., that being the temperature at which the imperial gallon is defined as containing 10 lb. avoirdupois of distilled water. The specific gravity of any sample of spirits thus determined, when multiplied by ten, gives the weight in pounds per imperial gallon, and the weight of any bulk of spirits divided by this number gives its volume at once in imperial gallons.