It seems contrary to all analogy, and all rules of reasoning to suppose, _a priori_, that an immunity which is found to subsist for a certain time in the usual and healthful state of the system, will gradually and insensibly wear away without any apparent cause, or any sensible change to indicate its extinction; and the facts which bear at all upon the question, so far from suggesting or supporting such a supposition, seem, in our apprehension, completely to refute and discredit it. Yet what in 1806 was accounted “contrary to all analogy,” and “completely refuted and discredited by facts,” is precisely what vaccinators now admit. Hence their cry for re-vaccination--septennially, triennially, annually. Dr. Lionel Beale, a great authority in the matter, recently owned to having been vaccinated ten times, and in terror of an epidemic was about to be vaccinated once more--a striking exemplification of contemporary theory and practice. To have foreseen such an issue would have confounded the early vaccinators. When re-vaccination was mentioned to Dr. Pearson, he denied its possibility; “for,” said he, “Vaccination is equivalent to smallpox, which cannot recur. If a child can be re-vaccinated, then it can take smallpox; _ergo_ vaccination is not an equivalent for smallpox; and where then is the good of it?” Where indeed! The Edinburgh reviewer was sufficiently impartial to recognise violence alike among Cowpoxers and Smallpoxers, and specified John Ping, Jenner’s bully, as an offender, describing his _Treatise on Cowpox_ as “one thousand and forty chaotic pages in defence of the new practice.” Ring verified the criticism by issuing a pamphlet, _The Beauties of the Edinburgh Review_ alias _the Stink-Pot of Literature_; reminding us of the man who writing to his wife from an inn-parlour remarked, “I must conclude, for an unmannerly Irishman is looking over my shoulder and reading every word I write;” an observation that was immediately clenched with, “You are a liar, sir; a liar!” FOOTNOTES: [169] _Shooting Niagara._ [170] “Neglect not, I exhort you, such proffered blessing. Secure yourselves from danger; preserve your children; and render most grateful thanks to Almighty God who has so providentially permitted to man this means of defence against the pestilence that walked in darkness, and the sickness that destroyed in the noon-day.”--_Address of the Rev. T. A. Warren to his Parishioners_, reprinted by the Royal Jennerian Society, 1803. [171] _A Treatise on the Lues Bovilla or Cowpox._ By Benjamin Moseley, M.D. Second Edition. London, 1805. Pp. 142. [172] Sidney’s _Life of Hill_, p. 225. [173] _Cowpox Inoculation Vindicated and Recommended from Matters of Fact._ By Rowland Hill, A.M. London, 1806. Pp. 72. [174] _An Oliver for a Rowland; or, a Cowpox Epistle to the Rev. Rowland Hill under the wing of Surrey Chapel._ By Benjamin Moseley, M.D. Tenth Edition. London, 1807. Pp. 102.