Section 2(1)(e) in Jharkhand Excise (Country Liquor Manufacturing, Bottling and Storage) Rules, 2018
(e)"London Proof (L.P)" or "Proof" means the strength of proof as ascertained by means of Sykes, Hydrometer and Denotes that liquor which at the temperature of 510 Fahrenheit weigh exactly 12/13th part of an equal measure of the distilled water;