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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.”

Thus frustrated, Jenner’s ingenuity took another turn. It was the belief of farriers that if infected in dressing horses’ greasy heels, they too were secure from smallpox. The area of this conviction was narrower than that of the dairy-maids, farriers being neither so numerous, nor so observant of their beauty: but Jenner entertained their faith and converted it to his purpose.

Horsegrease protected from smallpox, if cowpox did not. But might there not be one sort of cowpox that answered to the dairy-maids’ faith, if another sort did not? Happy thought! The defensive sort was derived from the horsegrease which protected the farriers: the non-defensive originated spontaneously on the cows. Men, fresh from handling horses’ greasy heels, milked cows and communicated to them the horses’ disease. Milkmaids, who in turn contracted from the cows that sort of pox, were like the farriers secure from smallpox, yea securer; whilst milkmaids who contracted pox spontaneously developed on cows were not secure. The milkmaids’ superstition was therefore justifiable: they were right and they were wrong—right when they got pox through the cow from the horse; wrong when they got pox from the cow simply.

Why then, it may be asked, did not Jenner dismiss the cow from consideration? Why did he not base his prescription on the farriers’ experience, and use and recommend horsegrease exclusively for inoculation? The question is an obvious one, but it is not easy to make out Jenner’s answer with precision. His assertion was, that—

which was to say that horsegrease attained its highest prophylaxy after transmission through the cow.

Such was the doctrine of the Inquiry, “that master-piece of medical induction.”

When the doctrine came to be reduced to practice, difficulties arose. Cowpox was considered wholesome and credible, whilst horsegrease was repulsive and incredible. Still fact was fact; and many were ready to accept horsegrease through the cow, or without the cow, if such indeed were the source of the new salvation. Cowpox proved to be a rare commodity, whilst horsegrease was common, and numerous attempts were made to produce cowpox by means of grease, but ineffectually. At some attempts, Jenner officiated. Marshall records that—

To this discomfiture Jenner had to submit. His ascription of cowpox to horsegrease was stigmatised as an error of which the less that was said the better. It is true that other experimenters were more successful, and that Loy of Whitby and Sacco of Milan dispensed with the cow as a superfluity and used matter direct from the horse for inoculation, passing the virus from arm to arm into general circulation until what was equine was lost sight of and indistinguishable from what was vaccine; but Jenner did not care to be justified at the risk of his popularity and the money on which he had set his heart. He saw how the wind of public favour was blowing, and went with it. Since horsegrease was disliked, he consented to its oblivion. Pearson, the chief promoter and organiser of vaccination, scoffed at horsegrease, and used spontaneous cowpox, which Jenner knew was of no avail against smallpox; but he entered no protest upon that score. On the contrary, he let the futile practice go on; he claimed it as his own; and he set about manufacturing excuses for the failures which were imminent.

Spurious cowpox was one of the most dexterous of these excuses. If injury or smallpox followed vaccination, the disaster was ascribed to spurious cowpox. Jenner’s Further Observations, published in 1799, was designed to teach “how to distinguish with accuracy between that peculiar pustule which is the true Cow Pock and that which is spurious;” and in his Origin of the Vaccine Inoculation in 1801 even greater stress was laid on the distinction. By and bye, however, the excuse worked more harm than advantage. People got terrified with the mischiefs ascribed to spurious cowpox, and as which was genuine and which spurious was only discoverable in their consequences, they began to decline to have either. It then became expedient to deny spurious cowpox, which Jenner did. He confessed to the Royal College of Physicians that there was not a true and a false cowpox; and that by spurious cowpox he “meant nothing more than to express irregularity in the form and progress of the vaccine pustule from which its efficacy is inferred.”

In view of facts like these, there is little cause for surprise that the publication of Jenner’s Inquiry with its two supplements was not continued. What he set forth as essential was treated as illusory, whilst the cowpox in which he had taught there was no security had been brought into use everywhere. Why therefore embarrass himself with proclamations of his own blunders? The believers in vaccination were good-natured and incurious, and he had their homage, which was agreeable and profitable, and why should he dissipate it? The Inquiry was printed for the third time in 1801, but “this master-piece of medical induction” has never been republished; and the probability is, that if ever reproduced, it will be to prove to the world the emptiness of its author’s pretensions.

Jenner’s original promises of immunity from smallpox by inoculation with horsegrease cowpox were absolute. Thus he wrote—

Experience was not slow to demonstrate the futility of these assurances. At first the facts were flatly denied: it was impossible for smallpox to succeed cowpox. The evidence, however, grew too strong to be outsworn, and then it was said the cowpox must have been spurious. As failures accumulated over the operations of Jenner himself and his choice disciples (who were naturally presumed to know and avoid spurious cowpox) they began to lay great stress on the fact that smallpox itself did not always avert a subsequent attack; and if smallpox did not save from smallpox, why, they demanded, should cowpox be expected to do more?[194] Why, indeed! Still the cases of smallpox after cowpox were as scores to those of smallpox after smallpox, and then the argument was reduced to a competition between variolation and vaccination. “You inoculators with smallpox,” said the vaccinators, “are continually having smallpox after variolation, and why should we be expected to be more successful?” Why, indeed! The inoculators with smallpox in turn denied that after efficient variolation smallpox ever occurred, or could possibly occur; and thus the wrangle went on. One thing was plain and certain—the original claim of Jenner for the absolute infallibility of Horsegrease Cowpox as a preventive of Smallpox was reduced and surrendered bit by bit until it came to this at last—it made Smallpox milder!

These repeated surrenders were, however, never ingenuous. Mistakes are inevitable, and they are forgiven when frankly confessed; but frank confession was not Jenner’s habit. When vaccination failures had become notorious in 1808, he had the hardihood to assert, that from the outset he had recognised that as smallpox did not always avert smallpox, neither did he expect cowpox to do so; and cited as proof of his prescience this passage from Further Observations in 1799—

Here Jenner made a bold draft on his reader’s ignorance. It was his claim for horsegrease cowpox that it conferred an absolute security from smallpox without any qualification whatever. The assumed prescience in 1799 is completely belied when we refer to his arrogant manifesto of 1801. These are his words—

Cowpox was thus set forth as a prophylactic with powers hitherto unknown and unique; so that Jenner was cut off from the claim of its equivalence with smallpox in character and consequences. He knew in 1799, as we have seen, that infection with smallpox did not render the constitution proof against the subsequent influence of the disease; but in 1801, as we see, it was his express contention that what smallpox failed to do that cowpox did—it protected the constitution perfectly and for ever from smallpox, and nothing to compare with it had ever appeared in the Annals of Medicine. It was only under the pressure of exposure and defeat that he humbled himself to write to Dunning, 1st March, 1806—

To this pass was the infallible preservative from smallpox, with nothing to match it in the Annals of Medicine, reduced within the experience of seven years!

The most thorough-going and far-reaching of Jenner’s excuses for vaccination failures were herpetic affections of the skin. In his journal we read—

To Mr. Dunning he wrote from Cheltenham, October 25th, 1804—

And again to the same correspondent, 23rd December, 1804—

Having thus detected an all-sufficient explanation of the failure of vaccination to prevent smallpox, he communicated his discovery to the Medical and Physical Journal, August, 1804, in a paper entitled, “On the Varieties and Modifications of the Vaccine Pustule occasioned by an Herpetic State of the Skin,” but he complained to Dunning “that it seemed not to have excited the slightest interest.” In order to call attention afresh to the subject, he had the article reprinted as a pamphlet at Cheltenham in 1806 and at Gloucester in 1819, but in vain. He complained to Baron in 1817 that he could not get the Board of the National Vaccine Establishment to attend to his cautions touching the interference of cutaneous diseases with the progress of the vaccine vesicle. “I am afraid,” he observed, “that the extreme ignorance of medical men on this subject will destroy the advantages which the world ought to derive from the practice.”[201]

What of course medical men with the least common sense perceived was, that the excuse provided for vaccination failures was too liberal to be worth anything. If the least cutaneous eruption was sufficient to frustrate vaccination, what operation could be pronounced efficient? for it could scarcely be intended that every patient should be stripped to the skin and minutely examined for herpetic vesicles. There was nothing transitory in Jenner’s opinion about herpes: he harped upon its mischiefs and omnipresence to the close of his life. William Dillwyn of Walthamstow having asked him for any observations that occurred to him on the practice of vaccination for the benefit of Friends in Philadelphia, Jenner replied in a letter dated Berkeley, 19th August, 1818, in which we find these remarks—

These complaints of the indifference of the medical world to his prophesying, show how completely the business of vaccination had passed out of Jenner’s hands. The influence of herpes on vaccination, although declared by him to be of the utmost importance, even to the extent of imperilling the advantages of the practice, was disregarded as unworthy of serious attention.

Another of Jenner’s apologetics was a pamphlet in 1808[203] designed to explain away the failure of the variolous test—the test that deceived so many in the early days of vaccination. The inoculated with cowpox were inoculated with smallpox, and when the smallpox did not “take,” it was said, “Behold the perfect protection!” The smallpox inoculators complained bitterly of the hocus-pocus. “No wonder,” they said, “that when the system is in a fever with bestial corruption, that human pox will not ‘take,’ but try after awhile.” And they did try after awhile, and it was found that the vaccinated could be inoculated with smallpox like the unvaccinated. Indeed, when it was seen that the vaccinated fell victims to smallpox, many who had been vaccinated resorted to the smallpox inoculators for their supposed superior protection, and received it without hindrance from their previous vaccination. It therefore became judicious to disown the variolous test; but neither in this case was the surrender frankly made, but with prevarication that deprived it of all grace. What the smallpox inoculators maintained, Jenner had to allow, but after this fashion—

For the variolous he recommended the substitution of the vaccine test; saying—

Which was to say that vaccination immediately after vaccination would be found impossible—the later practice of periodical re-vaccination being unforeseen.

Jenner might have perceived that after his proclamation of the influence of herpes on vaccination, there was nothing to be said for the variolous test. When he consented to run vaccination on the same terms as variolation, and admitted that it would be wrong to expect more from the one practice than from the other, he was bound in consistency to allow that if vaccination was frustrated by eruptions of the skin, it was matter of consequence that variolation should be frustrated by the fever of vaccination. He informed Dillwyn that he destroyed cutaneous eruptions by the application of unguentum hydrargyri nitrati, and then vaccinated with success. The smallpox inoculators did so likewise. When the irritation induced by vaccination had had time to subside, they too variolated with success.

The letter to Dillwyn, 1818, contains some other points which it is instructive to note. For example, the following passage proves two things, first, how notorious had become vaccination failures; and, second, how vaccination, from an easy art that any one might practise, had been converted into a mystery to which even “an eminent surgeon” might be unequal. Jenner says—

A report having got abroad that Jenner had renounced his faith in vaccination, he replied to Dillwyn—

In presence of such a declaration, it is easy to understand why the Inquiry with its supplements was kept out of print, and never referred to. His confidence in vaccination not in the least diminished! In the words cited, he surrendered afresh the claim with which he started, and for which he was paid, namely, that inoculation with cowpox rendered the constitution proof against smallpox for life, and that the protection thus afforded was without precedent in medical experience.

Having thus, under stress of necessity, reduced vaccination to the level of variolation, and tried to shelter the failures of the one practice under those of the other, the spirit of the old quack surviving, he went on to prophesy in the familiar strain—

With Jenner’s turn for romance, there is no need for dealing with a statement like the foregoing seriously, else we might ask what was the prevalence of smallpox in Gloucestershire before vaccination? and to what extent had it been cultivated by inoculators? Throughout England there was a remarkable subsidence of smallpox precedent to the introduction of vaccination (for which vaccination obtained the credit), which subsidence was no doubt accelerated by the cessation of variolation. Jenner resumes—

There was no checking Jenner when he rose into rhodomontade about the myriads of Asia and the vastness of America, but descending to the definite in Ceylon and Sweden we can test him with precision, and as to both we shall find his statements at wide variance with facts. For the present, however, let us keep to our own country, and note especially what he had to assert of London in 1818—

In London in 1818 the deaths from smallpox were low (421); but a single year is of little account, and must be viewed in relation to preceding years. Here we have a statement for the decade, 1811-20, taken from the metropolitan Bills of Mortality.

From this statement we see that the decrease in London smallpox that set in toward the close of the 18th Century was maintained; but that vaccination had aught to do with the decrease there is no reason to believe—unless in so far as the new practice discouraged variolation. How, we ask, could the vaccination of one-tenth of the Londoners (if so many) reduce the smallpox among nine-tenths? We have also to observe that mortality from fevers abated in common with smallpox; and it cannot be pretended that that abatement was also due to vaccination! The rational assumption is, that what diminished fevers in London, likewise diminished smallpox. Nor should we overlook the fact, that as the deaths from smallpox declined, those from measles increased; nor the probability that many deaths formerly ascribed to smallpox were derived from measles, and that part of the decline in one column is accounted for by the increase in the other.

Jenner’s assertion, that the national mortality from smallpox had been reduced from more than 40,000 to less than 6000 annually, had no basis whatever in reality. As we know, the 40,000 deaths were got by multiplying the deaths of a bad year of London smallpox by the population of the United Kingdom—as if London were the standard of England, Ireland, and Scotland! How he obtained the reduced number of 6000 we are left to conjecture. In reviewing Jenner’s writings we are startled with his inconsistencies, and scarcely less with the carelessness and credulity of his adherents. He set out with the common knowledge that cowpox did not prevent smallpox, and for that reason he substituted pox generated by horsegrease on the cow. Horsegrease cowpox could not, however, be procured on demand; and was, moreover, disliked on the score of its origin; and cowpox was resorted to by Pearson and Woodville, and diffused everywhere with acclamation; and Jenner did not only not object, but took credit, and actually was allowed to take credit for the pox he had described as ineffective for the purpose designed! By and bye cowpox from horsegrease, or horsepox, according to the original recipe, was obtained and brought into circulation with Jenner’s sympathy, if without his open approval—he discerning that praise and pay were not to be had from that notion. After a while, horsegrease, or horsepox, was used for inoculation without the intervention of the cow; and that too entered into currency as vaccine, Jenner himself employing and distributing it, although according to his Inquiry it was not to be trusted to prevent smallpox.

I repeat these facts, even at the risk of tedium, because it is essential to have them clearly apprehended. For at least three descriptions of virus Jenner stood responsible, namely—

I.—Horsegrease Cowpox—the virus warranted in his Inquiry.

II.—Cowpox, known by Jenner to be ineffective in preventing smallpox, but favoured by the medical profession and the public.

III.—Horsegrease (said to have been horsepox), also described by Jenner as ineffective, but latterly used and diffused by him.

To which of these did he attribute the success claimed for vaccination? Apparently to all indifferently; but if one were as good as the others, why did he not say so, and proceed to explain how it was that cowpox did not save the Gloucestershire milk-maids, nor horsegrease the farriers from smallpox? Was it that the power to put such questions, and to answer them, does not consist with the quack’s intelligence; and that in his lucre he rests content? Observe, too, how when credit was to be had for London vaccination, Jenner took it, though at mortal enmity with the chief agent in the work, repudiating Walker’s practice as subversive of principles he considered essential to success.

Jenner’s final publication in 1822 had nothing to do with vaccination, but was a bid for fame in a new direction.[204] It was an attempt to originate a new method of cure by irritating the skin with tartarated antimony. He had dabbled with the chemical when a young man, and John Hunter had suggested that his preparation should be sold and puffed as Jenner’s Tartar Emetic. In his last years he returned to it, and produced a series of cases to prove how many diseases might be alleviated and removed by using it as a counter-irritant—just as in the Inquiry he recommended cowpox inoculation with the same intention. The matter does not concern us further than to observe that the vesicles and scars produced by tartarated antimony are almost indistinguishable from those of vaccination; and that Hufeland, the German Nestor of Medicine, taught and proved that tartar emetic was every whit as effective against smallpox as cowpox—an opinion from which I see no reason to dissent.