One other matter must be referred to before taking leave of the Commissioners. I have already shown how completely they ignore the elaborate and valuable evidence, statistical tables and diagrams, furnished by those who oppose vaccination, such as were brought before them by Mr. Biggs of Leicester, Mr. A. Wheeler, and Mr. William Tebb, who, though all were examined and cross-examined on the minutest details, might as well never have appeared so far as any notice in the Final Report is concerned. But there is also a very elaborate paper contributed by Dr. Adolf Vogt, Professor of Hygiene and Sanitary Statistics in the University of Berne, who offered to come to London and submit to cross-examination upon it, which, however, the Commission did not consider necessary. This paper, a translation of which is printed in the Appendix to the 6th Report, p. 689, is especially valuable as the work of a thorough statistician, who, from his position, has access to the whole body of European official statistics, and his discussion goes to the very root of the whole question. The treatise is divided into nine chapters, and occupies thirty-four closely printed pages of the Blue Book; but, being an elaborate argument founded mainly on a scientific treatment of statistics, there was probably no member of the Commission capable of adequately dealing with it. Yet it is of more value than fully nine-tenths of the remainder of the voluminous reports, with their 31,398 questions and answers. Professor Vogt’s treatise covers almost the whole ground, medical and statistical, and enforces many of the facts and arguments I have myself adduced. But there are two points which must be especially mentioned. His first chapter is headed—“_A Previous Attack of Small-pox does not Confer Immunity_.” I have long been of opinion that this was the case, and have by me a brief statement, written six years since, to show that the rarity of second attacks may in all probability be fully explained by the doctrine of chances. But I had not statistics sufficient to prove this. Professor Vogt, however, having the statistical tables of all Europe at his command, is able to show not only that the calculus of probabilities itself explains the rarity of a second attack of small-pox, but that second attacks occur more frequently than they should do on the doctrine of chances alone, indicating that, instead of there being any _immunity_, there is really a somewhat increased _susceptibility_ to a second attack![21] This being the case, it becomes really ludicrous to read the questions and answers and the serious discussions as to whether a “good vaccination” protects more or less than a previous attack of small-pox. Some think the protection is the same, but the greater number think it is not quite so much. Even the most ardent vaccinists do not claim a greater protection. But none of them ever doubt the _fact_ of the protection gained by having had the