English chemist William Hyde Wollaston invented the Scale of Chemical Equivalents which is explained in this publication along with a foldout plate illustrating Dr. Wollaston's Synoptic Scale of Chemical Equivalents. Used as a pedagogical tool in the teaching of chemistry, this redesigned scale features Hydrogen as the "radix of unity." The scale assists in identifying the proportions of the constituents of a compound of known weight.

Select content digitized includes cover, title page and foldout plate containing Dr. Wollaston's Synoptic Scale of Chemical Equivalents.