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CHAPTER XVIII.

HORSEGREASE AS A SOURCE OF VACCINE.

In order to complete the account of Jenner’s awards and the adoption of Vaccination by Parliament, I have passed over several matters of interest and significance, which I shall now proceed to deal with, commencing with the tactics of our hero in relation to Horsegrease.

In his Inquiry, published in 1798, Jenner set forth Horsegrease as the origin of that form of Cowpox, which, when inoculated on the human subject, ensured life-long security from Smallpox. Many attempts were consequently made to produce pox on the teats of cows by inoculating them with Horsegrease, but in vain; and the possibility became discredited. Moreover, the notion of inoculation with Horsegrease, either immediately or through the cow, was disliked intensely. It was pronounced repulsive. Why virus from horses’ heels should be more repulsive than virus from cows’ teats was not explained; but, as we know, there is no accounting for tastes. Many who eat beef with relish would start with disgust from horse-flesh. A story is told of a Wesleyan who rebuked a sister for wearing feathers in her hat, and was sharply referred to the existence of flowers in her own. “Yes, sister dear,” was the cogent reply, “but we must draw the line somewhere, and it is drawn at feathers.” The line was drawn at Horsegrease, and the origin of Cowpox as asserted by Jenner and his country acquaintance was conveniently denied. Jenner was not slow to perceive how the wind of opinion was blowing, and let Horsegrease drop. He said not a word about it in his petition to Parliament in 1802, nor did he again advance it as a reason for consideration.

Now, why was this? Was it because he had ceased to believe that Cowpox originated in Horsegrease? Not at all! Why, then, did he not vindicate his opinion and confront vulgar prejudice? Simply because he had the wit to discern, that whilst he might get something out of the national purse for the Cowpox recipe, he could get nothing for the Horsegrease one. As Dr. Pearson observed, “The very name of Horsegrease was like to have wrecked the whole concern”—an observation that Dr. Mason Good confirms in saying, “The mere idea of using the matter of grease from the horse’s heel excited from the first so deep and extensive a disgust that Cowpox Inoculation had nearly fallen a sacrifice from the supposed union of the two diseases.”

It is not to be supposed that I am censuring Jenner as a tradesman.[142] If any of us had two patents for sale, we should be great fools if we declined to take £30,000 for one without the other, or suffered one to prejudice the other, or tried to inflict any doctrine about them upon the purchaser. It is for those who go to market to adapt themselves to the market, and remember that sellers were made for buyers, and not buyers for sellers. Since then the public were ready to pay for Cowpox, whilst they shuddered at Horsegrease, it was not for Jenner to force Horsegrease upon them.

Such is mercantile logic; and on its own conditions it is irrefragable; but it is not the custom to deal with Jenner as a tradesman, but as a man of science, and to range him with great discoverers, inventors, and benefactors of mankind; and here it is that I decidedly demur. What, I ask, did he discover? He did not discover that Cowpox prevented Smallpox: that was the dairy-maids’ faith. He did not discover that Horsegrease prevented Smallpox: that was the farriers’ faith. He did not discover that Horsegrease on milkers’ hands begot pox on cows’ teats: that was the farmers’ belief. He did not discover that inoculated virus could be conveyed from arm to arm: that was an existing practice. What then did he discover? He discovered nothing. He did no more than take the vulgar opinion of his neighbourhood to the London market. He made a few perfunctory experiments by way of confirmation, advertised them in a book, and by good or ill luck the notion was caught up, and worked to practical issues, chiefly by Pearson, who thereby incurred the full malignity of Jenner’s jealousy.

The distinction between a man of science and a tradesman is this, that the mind of the one is set on the extraction of truth and the other on the extraction of profit. The man of science does not inquire what the public may be pleased to know and pay for, but he ascertains and defines what is fact, and leaves the public to adjust themselves thereto as they may find convenient. If they recognise the truth communicated, it is well for them; if they dislike or deny the truth, it is ill for them; but well or ill, the man of science is the disinterested expositor of what he knows to be true; not unfrequently, when his revelation vitally affronts popular prejudice, realising the blessing of those who are persecuted for righteousness’ sake.

What therefore I maintain concerning Jenner is, that the truth (as we may presume he regarded it) he did not fully reveal; that what he did reveal, he suffered to be derided and denied; that he was content to take credit for so much of it as was marketable; whilst his private conviction about Horsegrease remained unaffected, not only in theory, but in deliberate practice.

It is for me to establish these assertions.

First, I say, he did not fully reveal what he knew. In 1789 Jenner inoculated his son, Edward, an infant of 18 months, not with Cowpox, or with Horsegrease, but with Swinepox; and, according to the evidence of his own papers, the result was perfectly satisfactory. The child was subsequently inoculated with Smallpox on five or six different occasions, and always without effect. According to the well-known variolous test, he was proof against Smallpox. In short, there was nothing that Jenner ever adduced in favour of Cowpox that was not equally valid of Swinepox. And this Swinepox experiment was made nearly ten years prior to his advertisement of Cowpox and Horsegrease. Why, I ask, did he keep back the truth about Swinepox? When Cowpox was scarce, and every cow-house was explored for virus, why did he not recommend Swinepox as an alternative? Why, too, did he refrain from the obvious generalisation, that Cowpox, Horsegrease, Swinepox, and probably other sorts of pox, generated fevers, during the prevalence of which inoculation with Smallpox was not apt to take? The answer is plain, Because he had something to sell rather than something to teach.

In conformity with this conduct he suffered the origin of Cowpox in Horsegrease, and the specific virtue of grease to be derided and denied. “It was fortunate for Dr. Jenner, and the triumph of his discovery,” wrote Dr. Mason Good, “that a minuter attention to the subject gave sufficient proof that there was no foundation for his opinion that Cowpox originated in Horsegrease, nor that any connection existed between the diseases.”[143] Such was the convenient medical verdict, which Jenner did not venture to disturb, though all the while persuaded of its error. There were failures to inoculate cows with Horsegrease, but Thomas Tanner, veterinary surgeon, of Rockhampton, Gloucestershire, “had the merit,” says Dr. Baron, “of proving the truth of Jenner’s statement.”[144] He succeeded in communicating the disease to the cow from the heel of the horse, producing on the cow’s teat a complete vaccine pustule. “From handling the cow’s teats,” said Tanner, “I became myself infected and had two pustules on my hand, which brought on inflammation, and made me unwell for several days. The matter from the cow, and from my own hand, proved efficacious in infecting both human subjects and cattle.”[145] Jenner distributed the virus from Tanner, and it operated precisely like Cowpox. But the proof did not rest with Tanner: others repeated his experiment with similar issues. Dr. Loy of Whitby published in 1801 Some Observations on the Origin of the Cowpox, in which he confirmed Jenner’s country tales, and described how (dispensing with the cow) he managed to inoculate patients with Horsegrease, producing pustules identical with those from Cowpox, and subjecting the persons thus equinated to the variolous test with complete impunity. Yet, with so much to fortify him, Jenner kept silent. He preferred to be adjudged mistaken rather than risk the forfeit of public favour and pay. Nor might I blame him, had he frankly reasserted the integrity of the Gloucestershire faith, and allowed that since the public were ready to accept Cowpox without Horsegrease, it was not for him to stand in the way of their preference by an obstinate defence of what was non-essential in practice.

But the case for Horsegrease was yet stronger than I have stated. Dr. Sacco of Milan was sometimes described as “the prince of vaccinators” by reason of his enthusiasm, his professional attainments, and the facilities that were accorded to him in the Cisalpine Republic of those days for universal vaccination. He tried to generate pox on the cow with grease from the horse, but failed, and in 1801 reported to Jenner his failure. In 1803, however, he cried, Eureka! A coachman presented himself at the Milan Hospital suffering from an eruption contracted in grooming a horse with greasy heels. He was at once led off by Sacco to the Foundling Asylum, where nine children were inoculated from the vesicles on his hands. On three of the children the inoculation took, producing vesicles which were pronounced to be the same as those resulting from Cowpox. The virus was propagated from arm to arm, and distributed in all directions. Dr. Sacco from thenceforth avowed himself a Horsegreaser. “It is now admitted and settled,” he wrote to Jenner from Milan, 25th March, 1803, “that grease is the cause of vaccine, and we cannot too soon alter the designation to equine.”

Was the designation changed to equine? It was not, nor was the attempt made. Those chiefly concerned in promoting vaccination in England would not hear of Horsegrease, and many were ready to swear that in the matter of pox, the horse and the cow had no connection whatever, and that Jenner had too hastily assumed the truth of a vulgar west country opinion.

Dr. De Carro of Vienna, who described himself as Jenner’s friend and first apostle, having effected the first vaccination on the Continent and transmitted the first charge of vaccine to India, was also a Horsegreaser. Whilst Jenner was judiciously holding his tongue about Horsegrease in England, he wrote to De Carro congratulating him on his success in conveying Cowpox to the East, and ascribing the failure of the English attempts to the absurd prejudice against Horsegrease, which Dr. Loy had, however, completely annihilated. Here are his words under date, 28th March, 1803—

How the clamorous opposition to Horsegrease had deprived Hindoos of the earlier blessing of vaccination, we are left to conjecture. Perhaps he meant that Horsegrease would have borne transit to India better than Cowpox, or that the Hindoos themselves might have resorted to horses with greasy heels.

In reply, 22nd April, 1803, De Carro wrote to Jenner commending his moderation in maintaining silence toward his antagonists—little apprehending the motives of that silence. Pearson’s conduct, he thought, bordered on insanity. “I am extremely glad,” he continued, “that you have treated it with the contempt it deserves, though I am happy to see that your friends have exposed his ridiculous and malevolent designs.”

De Carro was intimate with Sacco of Milan, and from him received virus derived from Horsegrease, which he used indiscriminately with Cowpox, until in Vienna it was unknown who were vaccinated and who equinated.[147]

De Carro was also in correspondence with Dr. La Font, a French physician, established at Salonica, who was likewise a Horsegreaser. He discovered that the Macedonian farriers recognised three sorts of grease in horses, called in general javart, and discriminated as l’écrouelleux, le phlegmoneux, et la variolique.[148] With the variolous grease, La Font inoculated two boys, and from them other children, reproducing the experience of Loy of Whitby and Sacco of Milan. De Carro in communicating La Font’s success to Jenner, 21st June, 1803, observed, “These particulars, I hope, will silence all those who still doubt the truth of your doctrine as to the connection of Grease, Cowpox, and Smallpox”—Jenner holding that Smallpox was a malignant variety of Cowpox, whilst Cowpox came out of Horsegrease.

Notwithstanding these confirmations and his boast that the opposition of Pearson and Woodville was silenced for ever, Jenner suffered judgment to go against him. He recognised that it was expedient that the connection between Horsegrease and Cowpox should be denied. He had his bill to settle with the English public, and it was not for him to make difficulties. A curious evidence of how thoroughly the unpopular truth was suppressed is furnished by Dr. Willan’s treatise On Vaccine Inoculation, published in 1806. There is not a word or hint in it concerning Horsegrease. The treatise was the work of a competent physician, who set forth what was known of vaccination (from the standpoint of belief) with fulness and clearness, accompanied with an appendix of letters and reports from Jenner himself, from Pearson and other experts in the new practice—but as to Horsegrease, the silence was absolute. How the disagreeable truth was so effectually covered up is more than I can account for. It was not mentioned in the debates in Parliament, nor was it referred to in the reports of the Colleges of Physicians and Surgeons, nor did the opponents of vaccination use it with the force that might have been expected. One explanation is, that Jenner’s Inquiry never entered into general circulation, that no popular edition ever appeared, and that it was chiefly known at second hand. The leading representatives of vaccination, moreover, so boldly disowned Horsegrease and Jenner’s authority in ascribing Cowpox to its parentage, that there was little use in charging them with it; whilst all the while Jenner offered no open resistance to those who contemned him for one mistake, but exhausted the language of adulation on his imputed merit. Thus we suppose it came to pass that at the end of twenty years Dr. Mason Good, as the exponent of orthodox medical faith, felt justified in asserting that there was no foundation for the opinion that Cowpox originated in Horsegrease, nor that any connection existed between the diseases, and that it was fortunate for Jenner and the triumph of his discovery that the fact was so.

Jenner was silenced, but was he convinced? How could he be convinced? Horsegrease as the origin of Cowpox might be voted detestable and impossible, but there was the evidence of the country folk, confirmed by Tanner, Loy, Sacco, De Carro, and La Font; and though a weak man may be put down, or think it worth while to be accounted mistaken, yet, in the stillness of his mind, he knows that facts are facts whatever may be said to the contrary. When, therefore, Jenner had filled his purse, obtaining all he could expect from public favour, and was clear of London, and the oppression of its savants, he reverted to his first opinion as true—true and untrue, true with a distinction, which I shall presently define. Writing to James Moore, Director of the National Vaccine Establishment, from Berkeley, on 23rd July, 1813, he observed—

And in a subsequent note of 1st August, he repeated—

To Moore again he wrote from Cheltenham, 27th October, 1813—

Then we have a memorandum of Jenner’s, dated 1st April, 1817, wherein he thus traces the course of the virus—

Which was to say, that they were subsequently inoculated with Smallpox without effect. Among Jenner’s papers, there were other entries to the same purpose, thus—

This equine virus from Jane King was extensively diffused. It was, we see, sent to London; it was also sent to Edinburgh;[154] and Dr. Baron says he had supplies of it for use in the Gloucester Infirmary. Baron relates that in the following year he was able to return the gift, having obtained virus from the hands of a boy infected directly from the horse. Here is Jenner’s acknowledgment of the present, dated 25th April, 1818—

It is surely unnecessary to adduce further evidence of what was Jenner’s mature faith and deliberate practice. Further, it is manifest that to the end of his career he held that pox in the cow was not only derived from grease in the horse, but that it was exclusively derived from the horse, and, that apart from the horse, Cowpox would cease to exist. Owing to the multiplication of vaccination failures, it began to be conjectured that vaccine might be worn out by transmission from arm-to-arm, and that a reversion to the cow might be expedient; and discussing the question in a letter to Moore, dated 5th March, 1816, Jenner advanced the objection—

Why did not Moore rejoin, Where is the difficulty? Suppose pox driven from the herds, what conceivable reason was there for anxiety when the cow had become a demonstrated superfluity?—when, in Jenner’s own words, “the true and genuine life-preserving fluid” might be drawn direct from horses’ heels? Except for the perpetuation of imposture, the cow in the case had ceased to have any value whatever. But, as so often happens with quacks, their minds become so saturated with their own humbug that there is nothing left of common-sense.

Having thus proved my assertions concerning Jenner, it may be reasonably asked, How was it that some got Cowpox by means of Horsegrease when others could not? for, it may be argued, that if Cowpox issued straight and invariably from inoculated Horsegrease, not even the most resolute prejudice against Horsegrease could have permanently kept back the truth.

The answer is, that Cowpox never came out of what is commonly known as Horsegrease. The statement made by Jenner in his Inquiry of 1798 that—

infected cows and begot pox was a blunder, which he explicitly reversed fifteen years afterwards in his letter to Moore of 27th October, 1813, already cited—

Jenner, we have always to remember, was a slovenly investigator, not apt to take pains, but apt to eke out observation with invention. His friend, “honest Jack Baron of Gloucester,” who himself inoculated with horse virus unmodified by the cow, actually wrote Jenner’s life in two volumes, and not until the work was ready for the binder did he discover that he was in error in common with his master in ascribing Cowpox to Horsegrease! Such was the intellectual muddle in which these prophets of vaccination operated! In a note stuck at the end of the second volume, we have the following amazing confession, made, remember, in 1838, fifteen years after the chief conjurer’s death—

Here we have the secret and desired explanation. It was out of Horsepox, and not out of Horsegrease, that Cowpox was derived, and in confounding grease with pox, Jenner mystified himself and others, and obscured the whole doctrine of vaccination. The Macedonian farriers who in 1803 informed La Font that they recognised three sorts of grease, and one of them variolous, were more accurate observers than the Gloucestershire farriers and farmers whose opinion Jenner lazily retailed. Whether he had any clear apprehension of his own blunder is not apparent. We have seen how long it took his biographer, Baron, to find it out. This is certain, that he made no public attempt to set right what he had so egregiously set wrong, nor to withdraw the statement in his Inquiry that Horsegrease only acquired its efficacy against Smallpox after inoculation on the cow.

Lastly, we may inquire what is the present state of opinion as to Horsegrease and Cowpox? When difficult questions are asked, we usually turn to our cyclopædias, and taking down Hooper’s Lexicon Medicum, 8th ed. 1848, Art. Cowpox, we read—

Genuine Cowpox communicated by a horse is surely a bull of the first magnitude! The Encyclopædia Britannica, 8th ed. 1860, Art. Vaccination, illuminates us thus—

An established fact, indeed!—established in quicksand!

Some say the Gloucestershire farmers and Jenner were correct in attributing Cowpox to Horsegrease, and that they can only he charged with mistake in nomenclature. When they said Horsegrease, they meant Horsepox, not discriminating between maladies that sometimes occurred together. No one now believes that the affection recognised by veterinarians as “grease” ever originated Cowpox. The same rural authorities, including Jenner, held that where there was no Horsepox, there could be no Cowpox; but, so far as I can make out, that conclusion is surrendered. Pox on the horse may generate pox on the cow, but the cow may have pox without the horse.

At this point comes the tug of war. If cows have pox, how do they contract the malady? Speaking at the London Conference on Animal Vaccination in December, 1879, Professor J. B. Simonds, Principal of the Royal Veterinary College, said—

Professor Simonds and others believe that Cowpox as described by Jenner was a parasitic affection of Smallpox, probably communicated by milkers; and that Ceely, Badcock, and others did intentionally, what milkers had done inadvertently, when they inoculated cattle with Smallpox in order to create virus for vaccination. On the other hand, those who assert the independent existence of Cowpox, hold no terms with this heresy. As Dr. Cameron says, “We can no more make Smallpox into Cowpox than by stunting an oak-tree we can make it a gooseberry bush.” Fortunately I have no call to pronounce judgment on the controversy. The more it rages, the better I like it, and if the combatants disposed of each other as did the Kilkenny cats, I might not be very sorry.

A last word as to Horsepox. There seems to be little doubt that when inoculated on man it gives rise to vesicles indistinguishable from those raised by Cowpox. In 1863 Professor Bouley of Alfort produced pox on a cow by inoculating it with pox from a horse, and children were successfully vaccinated with the virus. In the Transactions of the Clinical Society, Vol. X., Mr. John Langton, describes the case of a groom who came to St. Bartholomew’s Hospital, 20th March, 1877, with an eruption caught from a horse exactly like that induced by vaccination; and there could be no question, says Mr. Langton, that the disease was the same as that described by Jenner as grease.

There is much virus in currency as vaccine that is equine, and many of us are equinated who suppose ourselves vaccinated; and it might be argued that we have been saved from Smallpox by reason of our equination. Why with all the notorious failures of vaccination, and of re-vaccination, some of the more audacious medical quacks do not recommend Horsepox as an infallible alternative, is not easy to understand. It would be a Napoleonic stroke; nor is it improbable that before vaccination is surrendered the attempt will be made. How easily it might be asserted that vaccination is a failure in so far as it has lost the original virtue of equination, that the remedy is to dismiss the cow and revert to the horse, from whose poxy heels, as the immortal Jenner observed, there issues “the true and genuine life-preserving fluid.” The oracle might be worked thus—

“Let us hear no more of pure lymph from the calf, too often, alas! an illusion. Sure and certain salvation from Smallpox can only be guaranteed to those inoculated with pure pox from the horse. Come then to the horse, the horse with pox! Come quickly! Come yourselves! Come with your wives! Come with your children! Come and be saved by Horsepox from the loathsome pestilence that decimates the human race and brings myriads to untimely graves!”