THIS work forms the fourth part of the series of monographs on the history of chemistry being published under the editorship of Prof. Kahlbaum, of Bâle, whose qualifications for the task have already been made known to English men of science in the notices of two of his earlier volumes published recently in these columns.1 The present instalment covers the period from the time of Schonbein's birth to the year 1849, an is divided into four sections, which comprise respectively the intervals 1799–1820, the “Wanderjahre” 1820–1828, the residence at Bâle from 1828 till the discovery of the passivity of iron towards the end of 1835, and the prosecution of the researches on the latter subject and on cognate electrical subjects from 1836 till 1849. There is a supplementary section dealing with Schonbein as a teacher and friend, which is by no means the least interesting part of the present volume. A perusal of the work will not only convince its readers that Schonbein was altogether a remarkable man as a thinker and experimenter, but that his personality and work could not have fallen for delineation and estimation into any better or more appreciative hands than those of Dr. Kahlbaum and his colleague. Christian Friedrich Schonbein, 1799–1868. Ein Blatt zur Geschichte des 19. Jahrhunderts. Von Georg W. A. Kahlbaum Ed. Schaer. I. Theil. Pp. xix + 230. (Leipzig: Johann Ambrosius Barth, 1900.)