Note 4 — PREFACE.
Reading edition
Mr. Margraaf has lately demonstrated, by a set of curious and accurate experiments, that this powder is of the nature, and possesses the properties, of the gypseous or selenitic substances. That such substances can be resolved into vitriolic acid and calcarious earth, and can be again composed by joining these two ingredients together. Mem. de l'Acad. de Berlin. an. 1750, p. 144.