The Edinburgh cases which Thomson heard of to the end of the epidemic numbered 556, assorted as follows[1105]:
310 had been vaccinated.
41 had had smallpox (doubtless by inoculation).
205 had neither been vaccinated nor had smallpox.
A large proportion had the crystalline eruption, while some of the deaths are put down to “malignant crystalline water-pock.” At Lanark and New Lanark the epidemic was also taken notice of[1106]. At the latter were situated the cotton mills managed under Robert Owen’s co-operative system; and it appears that vaccination had been somewhat generally carried out in this socialist community. The following was the incidence of smallpox upon 322 persons:
251 had been vaccinated.
3 were under vaccination at the time.
11 had been inoculated with smallpox, or had gone through the natural smallpox.
57 had neither been vaccinated nor variolated.
It is clear that this was the first severe and general epidemic in Scotland since the beginning of the century, although we have seen that the disease had never been out of Glasgow. Thomson saw well enough how that epidemiological fact told: “It is to the severity of this epidemic, I am convinced, that we ought to attribute the greatness of the number of the vaccinated who have been attacked by it, and not to any deterioration in the qualities of cowpox virus, or to any defects in the manner in which it has been employed. [Dewar said the same for Cupar Fife.] Had a variolous constitution of the atmosphere, similar to that which we have lately experienced, existed at the time Dr Jenner brought forward his discovery, it may be doubted whether it ever could have obtained the confidence of the public.” Thomson himself, professor of military surgery in Edinburgh and a person of high character, drew the most astonishing inferences from the tolerably simple facts of the epidemic in 1817-19. The crystalline was mixed with the ordinary pustular smallpox in this epidemic, as it had been in some 18th century epidemics; it was common to those who had been vaccinated and to those who had not been so; it occurred in those who had previously gone through the chickenpox. Yet the professor concluded that crystalline or hornpox was smallpox “modified” by vaccination, that it should be called “varioloid,” and that “modified” smallpox and chickenpox were the same disease.