To determine the weight of dry matter in the glaze slop.
By Brongniart's formula W = G(L-1000)/(G-1) calculate weight of dry matter in the glaze slop.
W = the dry weight of matter in the slop
L = the weight in grams of a litre of the slop
G = density of the dry matter relative to water (its relative density)
W is to be determined
L may be determined by measurement
G is unknown
Therefore G must be determined.
To determine G:
G = (Wd/Vd)/1
Wd = weight of dry matter
Vd =volume of dry matter
Weight Wd of dry matter may be determined by measurement.
But volume Vd of a given weight of dry matter is not known.
Therefore Vd must be determined.
Determine by displacement: take 1 litre water; add a given weight of dry matter and stir; measure displacement Vd in litres.