Toward the end of his life, he used to boast that he had performed upwards of one hundred thousand vaccinations. So far as vaccination prevailed in London, it was chiefly through Walker’s exertions; and he was just the character, being set going, to keep going whatever the adverse evidence or obloquy. He had his plans and his methods, and those who tried to modify them took nothing by their pains. He was a man to have his own way, and those who did not like him might leave him. Whether from incapacity or affectation, he made no attempt at politeness, and said precisely what he thought without accommodation. He was a piece of mechanism rather than of genial humanity. FOOTNOTES: [185] _The Vaccine Scourge containing the New Beggar’s Opera_ alias _the Walkerian Farce_, alias _the London Vaccine Hoax; in answer to Dr. Walker’s Jenneric Opera. A Rod for the Fool’s Back._ London, 1815. Pp. 122. Price 3s. [186] _A Caution against Vaccine Swindlers and Imposters._ By John Ring. London, 1816. Pp. 140. [187] _The Life of John Walker, M.D., Graduate of the University of Leyden; Licentiate of the Royal College of Physicians of London; and late Director of the Royal Jennerian and London Vaccine Institutions._ By John Epps, M.D., London, 1831. Pp. 342. [188] _John Walker’s Reply to James Moore._ London, 1818. Pp. 16. [189] _John Walker’s Reply to James Moore on his Mis-Statements respecting the Vaccine Establishments in the Metropolis and their Officers and Servants both Living and Dead._ London, 1818. Pp. 114. CHAPTER XXV. JENNER’S LATER WRITINGS. Jenner’s later writings were chiefly apologies for the failures of vaccination. His position was one of much difficulty, and its peculiarity is rarely, if ever, recognised. For example, how few know that his _Inquiry_ published in 1798, “that master-piece of medical induction,” according to Mr. John Simon, was kept out of print and referred to as rarely as possible after 1801-2. “Why?” The answer to the question is so important that at the risk of repetition I give it explicitly. The _Inquiry_ was suppressed because of its ascription of cowpox to horsegrease. It was the belief of dairy-maids in Gloucestershire that to have had cowpox was to be secure from smallpox. Jenner was much impressed by the rustic superstition, and brought it so persistently before his medical brethren at their convivial assemblies, that they threatened to expel him if he bored them any longer with the subject. “It is true,” they said, “that the maids believe an attack of cowpox keeps off smallpox, but we know they are wrong; for we are all familiar with cases of smallpox after cowpox.”