When fermentation has commenced in words so that the original gravity cannot be ascertained by the approved sacharometer, such gravity may be determined in the following manner—
(a) a sample is to be taken from any part of such worts and, after first being cleared from sediment by filtration, a definite quantity by measure at the temperature of 60 degrees fahrenheit shall be distilled;
(b) The distillate and residue shall each be made up at the temperature of 60 degrees fahrenheit with distilled water to the original measure of the quantity before distillation, and the gravity of each shall be ascertained;
(c) the manner of degrees by which the gravity of the distillate is less than the gravity of distilled water shall be deemed the spirit indication of the distillate;
(d) the degrees of gravity standing opposite to such spirit indication in the table in the schedule to these Regulations, added to the gravity of the residue expressed in degrees, shall be deemed to be the original gravity of the worts.