I am explicit to iteration because the truth is not recognised and may be accounted incredible. In another way the facts may be thrown into relief if we inquire, How would Jenner have fared had he applied for a patent? Suppose his several publications were submitted to a patent-agent, In what manner could a tenable specification be evolved from these materials? 1798.--_The Inquiry._ { Prescribes Horsegrease { Cowpox. { Slackens off from { Horsegrease Cowpox; { ascribes its 1799.--_Further Observations._ { efficacy to common 1800.--_Continuation of Observations._ { repute; and recommends { escharotics to arrest { its virulence. { Claim of discovery and 1801.--_Origin of Vaccine Inoculation._ { use of Cowpox, previously 1802.--Petition to Parliament. { condemned as spurious, { and Horsegrease Cowpox { dropped. By no ingenuity could a valid patent be got out of these documents. If Horsegrease Cowpox were selected as the basis of claim, what of the repudiation of Cowpox? and if Cowpox, what of Horsegrease Cowpox? And if Horsegrease Cowpox, what of the ascription of its virtue to common repute? And if Cowpox, was not the committee of the House of Commons in 1802 compelled to disallow Jenner’s claim to the discovery, and to define and limit his merit to the propagation of its virus from arm to arm? It was, however, Pearson and Woodville who first propagated Cowpox from arm to arm: Jenner’s start being made with Horsegrease Cowpox. But allowing him so much credit, it is nevertheless to be remembered that it was at that time a frequent practice to inoculate with Smallpox from arm to arm; and the substitution of Cowpox for Smallpox was a trifle for which to pay £10,000 and dissolve in ecstasies of admiration. FOOTNOTES: [128] _An Examination of the Report of the Committee of the House of Commons on the Claims of Remuneration for the Vaccine Pock Inoculation: containing a Statement of the Principal Historical Facts of the Vaccinia._ By George Pearson, M.D., F.R.S. London, 1802. 8vo. Pp. 196. [129] Such was the logic, but such was not the fact. If no one could have Smallpox twice, and if inoculated Cowpox was equivalent to Smallpox, no one could have Cowpox twice. Such was the argument. Pearson did not foresee its systematic refutation exemplified in Re-Vaccination, septennial, triennial, annual. [130] _Edinburgh Medical and Surgical Journal_, October, 1805. P. 513. CHAPTER XII. OBSERVATIONS ON THE POSITION IN 1802. One of my medical readers observes--