Of Servetus at this time I knew little or nothing, save that he had been burned as a heretic at Geneva by Calvin; and of his works I had seen no more than the extract in which he describes the pulmonary circulation. But meditating a revision and prospective publication of the Life of Harvey, with which I had prefaced my edition of his works, I went in search of further information concerning the ingenious anatomist who had not only outstripped his contemporaries, but his successors, by something like a century in making so important an induction as the Pulmonary Circulation. Nor had I far to go. In the ample stores of the British Museum Library I found a complete mine of Servetus-literature, and with access to the ‘Christianismi Restitutio,’ as reproduced by a learned physician, Dr. De Murr, and other works of the unfortunate Servetus, I encountered not only the physiologist already known to me, but the philosopher and scholar, the practical physician, freed from the fetters of mediæval routine, the geographer and astronomer, the biblical critic, in days when criticism of the kind, as we understand the term, was unimagined, and, alas for him! the most advanced and tolerant of the Reformers,--that sacred band to which Servetus by indefeasible right belongs. Luther, Calvin, and the rest repudiated the discipline and most of the outward rites and shows of the Roman Catholic Church; but they retained the most abstruse of her creeds. Servetus went at least as far as they in the rejection of externals; but, appealing to the scriptures of the New Testament, he satisfied himself and dared to say to the world that some of the fundamentals of Christianity as formulated by the Church of Rome, and acquiesced in by the Reformers of Germany, had no warrant in the teaching of the Prophet of Nazareth. Rejecting, as he did, the whole of the post-apostolic dogmatic accretions of the Church of Rome, Servetus is the source of the more ‘reasonable service’ we are now permitted to render, and--strange conjunction!--through his disastrous intercourse with Calvin, in no small measure the original of the free enquiry that is leading on to conclusions yet uncontemplated as to man’s relations to the Unseen and the Eternal.