But it would be unjust and untrue to assume that Roscoe set no value on theory: he fully recognized that she was the handmaid of Science. He who had so carefully studied Dalton’s papers and followed the workings of his mind in the light of a century’s experience, could not be unmindful of the worth of a fruitful conception. Mendelejeff’s generalization when it was first promulgated at once attracted him, and he followed its startling verifications with the greatest interest. It was always a matter of gratification that his detection of the true relations of vanadium to the other elements, just prior to the announcement of the Law of Periodicity, should have removed at least what would have been one apparent exception to the universality of its truth. * * * * * When Roscoe first settled in Manchester he lived with his mother in the house which had been occupied by his predecessor, the late Sir Edward Frankland. On his marriage he moved to Victoria Park, and subsequently, after the birth of his children, to a larger residence which was built for him in the same neighbourhood. It was a charming, well-arranged house surrounded by a good-sized garden, and with an excellent tennis lawn, to which his colleagues and senior students were freely invited on half-holidays during the summer months. In those days Roscoe was an active player, his reach and length of stride making him a formidable opponent. Both he and Lady Roscoe were fond of horses, and for some years riding in company with her was his usual form of outdoor exercise. Occasionally they would plan a driving tour together, and considerable sections of England and Wales were explored in this way. Whilst his children were young his long vacations were usually spent in the Lakes or in Scotland, or at Mr. Edmund Potter’s country seat, Camfield Place, near Hatfield. Roscoe’s long vacations usually meant to him either a change of occupation, or the continuance of a piece of literary work in new surroundings. Many of his memoirs were, in fact, put together during his vacations: it was only at such periods, when, free from the routine of lecturing, laboratory superintendence and College committees, that he could count upon the necessary freedom from interruption to arrange the results of an inquiry. The compilation of his smaller text-books was usually done at such times. The large treatise which he wrote with Schorlemmer, and which necessarily needed ready access to a library rich in serial publications, was mainly composed in Manchester. At one period of his career he was a frequent contributor to certain of the quarterly reviews, and the early volumes of _Nature_ contain occasional communications from his pen. It was a point of honour to translate any paper of Bunsen’s for the _Philosophical Magazine_.