HOMBERG, (WILHELM, GUILLAUME). - THE FIRST DETERMINATION OF EQUIVALENT WEIGHTS IN CHEMISTRY.

Observation sur la quantite exacte des sels volatiles Acides contenus dans les differens esprites acides. (+) Observations sur la quantité D'Acides absorbe's par les Alcalis terreux. (2 Memoirs).

(Paris, Jean Boudot, 1702 a. 1703). 4to. Without wrappers. Extracted from "Mémoires de l'Academie des Sciences". Année 1699 a. Année 1700. Pp. 44-51 and 1 textillustration. (depicting his + pp. 64-71.

First appearance of the 2 papers which represents Homberg's main works. In these papers he shows for the first time how to determine equal weights of substances, that all acids differ only in water content, and that dry acids combines in equal proportions with alkali. In the first paper he also gives the Pygnometer Bottle its modern form.

"Probably his most importent work was on the strenght of acids and the quantity required to neutralize a given quantity of alkali (two papers published in 1699 and 1700) - the papers offered - Homberg recognized that different alkalis neutralized the same acid in different proportion but believed that the relative strenghts of two acids could be determined by using the same alkali in each case. he treated the the question of neutralization (or dissolvability, as he called it) in quite quantitative fashion, showing that if an alkaline salt were treated with an acid, the gain of weight ofthe salt wasan indication of the amount of acid absorbed....Homberg nevertheless understood the fundamentals of the process and thereby laid the foundation for an understanding the nature of salts."(DSB VI, p. 478).

Parkinson "Breakthroughs" 1700 C.

Order-nr.: 44405