In the cloisters of the old monastery which then did duty as the Heidelberg laboratory, Roscoe was first indoctrinated into the art and mystery of quantitative chemical analysis, and he there acquired the familiarity with Bunsen’s methods and with his system of laboratory instruction that he was to turn to such signal account in the establishment and direction of the Manchester school of chemistry. Among his fellow-workers were Lothar Meyer, Pauli, Beilstein, Pebal, Schischkoff (a Russian officer who investigated with Bunsen the course of decomposition of fired gunpowder), Quincke, Bahr, Landolt, Baeyer, Lourenço, and, amongst Englishmen, Russell, Atkinson, and Matthiessen—a group of well-known names constituting a striking testimony to the influence and power of attraction of the great German chemist. One of Roscoe’s earliest quantitative exercises was in silicate analysis, and his first published paper, which appeared in _Liebig’s Annalen_ for 1854, was a joint production with Schönfeld on the composition of certain samples of gneiss. At the close of his second session he passed his doctor’s examination _summa cum laude_, and then embarked upon the well-known inquiry in association with Bunsen on the measurement of the chemical action of light, which occupied much of his time and energy during the next eight years. In the obituary notices he wrote for _Nature_ of August 31, 1899, and for the _Proceedings_ of the Royal Society, and more especially in the admirable Memorial Lecture which he gave to the Chemical Society, Roscoe has done full justice to the memory of Bunsen as a great chemist, pre-eminent as a discoverer and teacher, and lovable as a true and noble-hearted man. The Memorial Lecture was reprinted in America by the Smithsonian Institute, and translated into German to be prefixed to the collection of Bunsen’s works published by the Society—the Bunsen-Gesellschaft—founded in his honour. In course of their long and uninterrupted friendship he received many letters from his illustrious master. These, 126 in number, were suitably bound and presented by him to the Bunsen Society. Roscoe took advantage of the opportunity afforded by his residence in Germany to study its university system, and to make himself familiar with the general character of its working, and in his vacations he sought the acquaintance of its leading men of science, with some of whom he contracted lasting friendships. In his Autobiography, written in 1906, he gives expression to the sentiments of respect and esteem with which he regarded the Germany and his German friends of half a century ago: