In the title-page of his first essay, Dr Jenner called this singular malady of the cow’s paps by a new name—variolae vaccinae, or smallpox of the cow. Pearson, the earliest and most ardent of Jenner’s original supporters, and for several years thereafter a convinced vaccinist, at once took exception to the name variolae vaccinae “for the sake of precision of language and justness in thinking.” It is a palpable catachresis, says he, to designate what is called the cowpox by the denomination variolae vaccinae, because the cowpox is a specifically different distemper from the smallpox in essential particulars, namely, in the nature of its morbific poison and in its symptoms[1080].
That the term variolae vaccinae in Jenner’s title-page is used tropically can hardly be doubted; but it is not so easy to say which of the great classical tropes it is. It may be objected that “catachresis” is too general for the misuse of a word when that word is a scientific one and occurs in the leading title of a scientific book. Here we have the somewhat specific and purposeful use of a word in an unwonted sense, which, if it fall under any of the scholastic figures of speech, ought to be a figure more specifically defined than mere catachresis. In a matter so important as this one should find the exact figure if possible; but at the outset a difficulty arises, namely whether we should look for it in the usage of the rhetors, as Isocrates teaches, or in the usage of the logicians, as Aristotle lays down the definitions of tropes. If among the former class, the nearest is perhaps the hypocorisma, or attractive, agreeable name for something that is not so nice in itself. If among the latter, we shall hardly find a better than the metalepsis, which is a change more of mood than of meaning, namely the transition without proof from a supposition to an assertion. But in truth no single figure of the ancient teachers suits this modern instance. We require at least two. Metalepsis carries us so far, but synecdoche must supplement it. The term variolae vaccinae is a synecdoche in that it names the cause from the effect; it is a metalepsis in that it passes abruptly from the hypothetical mood to the categorical; and in respect that it does both at a stroke it is probably unique, and without precedent among the examples known to the ancients. Or again, leaving the graver figures, and translating the Latin name of Jenner’s title-page, one may try the figurative conversion of cowpox into smallpox by the standard of pure and legitimate paronomasia, of which there is a familiar English example in the conversion of a plant into an animal by the verbal play of horse-chestnut and chestnut horse in the minor premiss.
Some in more recent times, mistaking the figurative or rhetorical intention of Jenner, have understood his Latin name of cowpox as if there really were a smallpox of the cow (although not of the bull, nor of the steer, the maiden heifer or the calf of either sex). Not being able to find a smallpox of the cow in the natural way, they have thought to satisfy the legitimate requirements of proof by manufacturing it. Certain Germans of the Lower Rhine, where the cows ordinarily wear blankets, have wrapped the blankets taken from smallpox beds round the bodies of cows, after clipping the hair close; nothing was found to ensue in these interesting experiments except an occasional pimple which had probably been caused by the shears in the preliminary clipping. Others in England, France, America and India, have succeeded in raising a smallpox pustule at the point of puncture in the epidermis of the cow or in the more delicate transitional epithelium, the matter from which has produced smallpox in its turn[1081]. But these are academic exercises. The natural cowpox of the cow has been likened by none to the natural smallpox of man in a sustained comparison of all the anatomical and epidemiological particulars of each; nor, I am persuaded, will anyone ever attempt to draw out such a comparison. Variolae vaccinae as a name for cowpox was a figure of speech, and it is to misunderstand its original use to treat it as anything else.
The proof that cowpox had some power over smallpox consisted in trying to inoculate with the latter those who had been previously inoculated with the former. The accepted mode of testing the power of inoculated smallpox itself was to inoculate it again; at first the test for cowpox was to inoculate with smallpox, but after a few years the testing inoculation was done with cowpox itself. The effects of Suttonian inoculation with smallpox, as we have seen, were nearly always slight, and sometimes invisible (as in Watson’s practice at the Foundling Hospital). A previous inoculation with cowpox made them slighter still; but even with cowpox in the system, the pustules of smallpox rose where the matter had been inserted on the arm. It may be thought that there were only fine shades of difference between the effects of inoculation after cowpoxing and the effects of the same in a virgin soil; but some difference must have been perceived, for it was upon that, and upon nothing else, that the authority in favour of cowpox as a substitute for smallpox in inoculation was promptly established. The relationship between cowpox and smallpox was admitted by all to be in the nature of things “extraordinary,” as Jenner said, or a mystery, as others said; but as an empirical fact many believed it to be true, because the cowpoxed had less to show for the effects of inoculation with smallpox than if they had not been cowpoxed. Jenner himself is known to have made only two variolous tests. He used crude or watery matter from the local pustule of inoculated smallpox, and advised all his readers to do the same. In one of his two trials, a child Mary James had nearly the same effects from inoculation after cowpox that her mother and another child had from it without having been cowpoxed, namely the pustule or confluent group of pustules at the place of puncture, and the eruptive fever at the ninth day[1082].
In the earliest tests made independently of Jenner, five at Stonehouse[1083], near Stroud, and five at Stroud[1084], in the first months of 1799, the cowpoxed received smallpox afterwards by inoculation “in the usual slight manner.” In the practice at the Smallpox and Inoculation Hospital, London, in the spring and summer of 1799, many of the cowpoxed took smallpox by contagion from the atmosphere of the hospital, so that Woodville, after a period of perplexity, at length concluded that cowpox, while it was still active upon the arm, did not shut out the action of the smallpox virus in the constitution[1085].
The antecedent objections to cowpox, arising out of its non-variolous nature, were met by appealing to the results of experiments. The authority in favour of cowpox was speedily established on that ground, and has been continuous to the present time. The experimenters had to decide very nice points both in the way of observation and of reasoning. They had to appraise the margin of difference between the effects of Suttonian inoculation where cowpox had preceded and where it had not preceded. They had to allow for the first virus causing a swelling in the absorbent glands, which would obstruct the entrance of the second testing virus into the blood. They had to average the varying effects of Suttonian inoculation for its own sake, and the equally varying effects of it as the variolous test, and to find a broad difference between the two averages. Having decided that preceding cowpox infection did make a real and appreciable difference to the number of pustules resulting, at the spot or elsewhere, from the insertion of inoculated smallpox matter, or to the amount of fever, they had next to consider whether that degree of resistance by a cowpoxed person to inoculation were a good measure of his power to resist contagion reaching his vitals in the natural way. Their diligence and acumen may or may not have been equal to these things—it was a slack tide in medical science. Also they received little or no help from Dr Jenner himself, whose inventive genius was of the kind that is apt to leave the practical value, and even the theoretical probability, of the project to be tried by others. The inventor made interest with great personages—with the king, the duke of York, and the aristocracy of his county. His priority, and the merits of his project, were referred in 1802 to a Committee of the House of Commons, with Admiral Berkeley as chairman, which entered on its labours with a strong recommendation from the king, endorsed by Addington, the prime minister. They decided in favour of Dr Jenner’s claim for remuneration on all the issues, and on 2 June, 1802, the Committee of the whole House unanimously voted: “That it is the opinion of the Committee that a sum not exceeding £10,000 be granted to his Majesty to be paid as a remuneration to Dr Edward Jenner for promulgating the discovery of the Vaccine Inoculation, by which mode that dreadful malady the smallpox was prevented[1086].” On 29 July, 1807, a farther sum of £20,000 was voted to him; and on 8 June, 1808, a National Vaccine Establishment was appointed, at an annual cost of about £5,000.
Chronology of epidemics resumed from 1801.
In resuming the history of smallpox from the beginning of the present century, we come first to the deaths in the London Bills of Mortality, which are the only continuous figures. The bills of Parish Clerks’ Hall had failed, before they ceased, to include more than two-thirds, perhaps not much more than a half, of all the deaths in the capital. The great parishes of St Pancras and St Marylebone, which returned a somewhat excessive share of the deaths both from smallpox and from fever in the first two or three years of the Registration Act (1837-39), as well as the parishes of Chelsea and Kensington, were never included within the Bills; also much of the suburban extension on the other sides of London was never taken in. Meanwhile the area of the old Bills had actually become less populous owing to the displacement of dwelling houses by warehouses, workshops, counting houses, and the like, in the City, the Liberties and in certain out-parishes such as those bordering the Thames at the east end.
Still, the bills of mortality may be taken as showing on the whole fairly the proportion of smallpox deaths to other deaths, and the years of its greater outbursts.