The Report of the College is interesting as a historic confession and a mark of progress. The physicians who drew it up were the same men who in 1800 professed their unlimited confidence in Vaccination, whilst as yet they knew little about it, proclaiming in the newspapers that they considered it their duty to declare—

That those persons who have had the Cowpox are perfectly secure from the future infection of the Smallpox.

From a profession so unqualified an absolute retractation was not to be expected; but experience had begotten caution, and it is instructive to remark with what qualifications the retreat from the original position was attempted. Thus—

The security derived from Vaccination if not absolutely perfect is as nearly so as can perhaps be expected from any human discovery; for among several hundred thousand cases, with the results of which the College has been made acquainted, the number of alleged failures has been surprisingly small, so much so as to form no reasonable objection to the general adoption of Vaccination.

The Report was not the deliverance of men possessed with the confidence of 1800: throughout there was manifest the failing conviction which evades responsibility and seeks for confirmation from sources external to itself. After a reference to the Variolous Test, the Report ran on—

It appears from numerous observations communicated to the College, that those who have been vaccinated are secure from the contagion of epidemic Smallpox. Towns and districts of country in which Vaccination had been general, have afterwards had Smallpox prevalent on all sides of them without suffering from the contagion. There are also in the evidence a few examples of epidemic Smallpox having been subdued by a general Vaccination.

The liability to confound coincidence with cause was not unknown in 1807, and might have been suggested as a possible explanation of the cessation of a variolous epidemic contemporaneously with Vaccination; although at the present day Vaccination, when Smallpox is epidemic, is known to do little else than invite and extend the malady.

How the general (that was to say partial) Vaccination of certain towns and country districts secured universal exemption from Smallpox, the Physicians failed to explain. Extraordinary tales of Vicarious Vaccination were current and piously received. If a fraction of an urban or rural community happened to be vaccinated (usually a fraction least likely to be troubled with Smallpox in any event) and Smallpox did not break out, or did not widely prevail, the salvation of the community was ascribed to the Vicarious Vaccination. The phenomenon has, strange to say, escaped the attention of theologians, although medical men constantly attest its occurrence.

Ruefully was it conceded that Vaccination was not an absolute preservative from Smallpox, but the pain of concession was softened with the plea of mitigation—