ART. III. 1. On the Origin of the Vaccine Inoculation. By Edward Jenner, M. D. F. R. S. &c. London. 1801. 2. An Oration Delivered before the Medical Society of London, on the Occasion of Presenting Dr. Edward Jenner with a Medal, in Honour of his Discovery of Vaccine Inoculation. By Dr. Lettsom. London. 1804. 3. A Comparative Sketch of the Effects of Variolus and Vaccine Inoculation; being an Enumeration of the Facts not generally known, but which will enable the Public to form its own Judgment on the probable Importance of the Jennerian Discovery. By Thomas Pruen, Esq. London. 1807 TH HESE pamphlets are of a very old date,-and do not embrace one tenth of the number which the same subject was the means of calling forth. The promulgation of the Jennerian discovery caused, for some time, a general engagement throughout the lines of the English physicians; and we could fill up all the space we intend to devote to this article with barely enumerating the titles of the works which have been written by a Willan, a Ring, a Moore, a Mosely, a Squirril, and a-host of others whose names we have now forgotten. The three pamphlets, of which we have just transcribed the titles, afford us all the requisite materials for a short account of Dr. Jenner's life; and we shall, therefore, proceed to lay before our readers a brief abstract of their several contents. Edward Jenner is the son of the Rev. Stephen Jenner, M. A. of Oxford, rector of Rockhampton, and vicar of Berkely, in Gloucestershire,-and was born in the latter place on the 17th day of May, 1749. He lost his father at a very early age; but in the affectionate attentions of his two brothers, the Rev. John Jenner, B. D. fellow of Magdalen college, Oxford, and the Rev. Henry Jenner, vicar of Great Bedwin, Wilts, he found almost a sufficient remuneration for his loss. His classical education was received at Cirencester,—and his medical education at Sudbury. In 1770 he took up his residence in London, with John Hunter, the anatomist. As natural history was a collateral department of anatomical study, Dr. Hunter published frequent essays on that subject, during the two years which Jenner spent with him:-the name of his new pupil was always introduced with approbation; and so highly indeed did the doctor rate his investigative powers, that he made him a liberal proposal of co-operation in a course of lectures upon natural history, which he was then preparing to deliver. About the same period a skilful comparative anatomist was wanted to accompany captain Cook in his first projected circumnavigation of the earth. Jenner was pointed out as the person most competent to fulfil such an office; and, although he was tempted by very liberal offers, his affection for his brother, John Jenner, induced him to reject a proposal which would carry him to such a distance from his native place. He accordingly determined to take up a permanent residence in Berkeley; and to content himself with prosecuting the natural history of his own country. Soon after this resolution was executed he was offered the degree of doctor of physic by the university of Erlington;-but, as the acceptance of the honour would have been incompatible with the discharge of his surgical duties, he was induced to decline the offer. In a community, however, where uncommon talents are rightly appreciated and rewarded, a person who is naturally inquisitive and observant will, first or last, be elevated into notice. While Jenner was dining with a large party at Bath, some article was introduced which required to be heated by the application of a candle. A question immediately arose,-whether the heat would be imparted more effectually, when the substance was held at a little distance above, or when it was directly immersed in the flame. Jenner requested that the candle might be placed by his side; when he immediately thrust his finger into the flame, and suffered it to remain for some time, without any apparent inconvenience. He then held the same finger a little above it,-and was obliged to withdraw his hand instantly. This, gentlemen,' said he, is a sufficient test.' He received the next day a note from general Smith, with the offer of a place in India, which, in the course of two or three years, would have insured him an annuity of 3000l. The proposal was submitted to his brother; and non-acceptance was the result of the consultation. Again, therefore, he retired to his beloved Berkeley,—with a resolution to spend his life in the comparatively inglorious occupation of a country surgeon. About the year 1775, inoculation for the small pox, after the Suttonian method, was very prevalent in Gloucestershire: and it was at this eventful period that Dr. Jenner commenced those investigations which ultimately terminated in the discovery of the vaccine inoculation. The steps which led to the discovery are concisely and perspicuously detailed by his own hand, in one of the pamphlets at the head of this article; and lest we should vitiate or impair the record of so important an event, we shall adopt without abridgment the very words of the Doctor himself. My inquiry into the nature of the cow pox commenced upwards of 25 years ago. My attention to this singular disease was first excited by observing, that among those whom in the country I was frequently called upon to inoculate, many resisted every effort to give them the small pox. These patients I found had undergone a disease they called the cow pox, contracted by milking cows affected with a peculiar eruption on their teats. On inquiry, it appeared that it had been known among the dairies, time immemorial, and that a vague opinion prevailed that it was a preventive of the small pox. This opinion I found was, comparatively, new among them; for all the older farmers declared they had no such idea in their early days-a circumstance that seemed easily to be accounted for, from my knowing that the common people were very rarely inoculated for the small pox, till that practice was rendered general by the improved method introduced by the Suttons: so that the working people in the dairies were seldom put to the test of the preventive powers of the cow pox. In the course of the investigation of this subject, which, like all others of a complex and intricate nature, presented many difficulties, I found that some of those who seemed to have undergone the cow pox, nevertheless, on inoculation with the small pox, felt its influence just the same as if no disease had been communicated to them by the cow. This occurrence led me to inquire among the medical practitioners in the country around me, who all agreed in this sentiment, that the cow pox was not to be relied upon as a certain preventive of the small pox. This for a while damped, but did not extinguish, my ardour; for as I proceeded, I had the satisfaction to learn that the cow was subject to some varieties of spontaneous eruptions upon her teats; that they were all capable of communicating sores to the hands of the milkers; and that whatever sore was derived from the animal, was called in the dairy the cow pox. Thus I surmounted a great obstacle, and, in consequence, was led to form a distinction between these diseases, one of which only I have denominated the true, the others the spurious, cow pox, as they possess no specific power over the constitution. This impediment to my progress was not long removed, before another, of far greater magnitude in its appearances, started up. There were not wanting instances to prove, that when the true cow pox broke out among the cattle at a dairy, a person who had milked an infected animal, and had thereby apparently gone through the disease in common with others, was liable to receive the small pox afterwards. This, like the former obstacle, gave a painful check to my fond and aspiring hopes: but reflecting that the operations of nature are generally uniform, and that it was not probable the human constitution (having undergone the cow pox) should in some instances be perfectly shielded from the small pox, and in many others remain unprotected, I resumed my labours with redoubled ardour. The result was fortunate; for I now discovered that the virus of cow pox was liable to undergo progressive changes, from the same causes precisely as that of small pox; and that when it was applied to the human skin in its degenerated state, it would produce the ulcerative effects in as great a degree as when it was not decomposed, and sometimes far greater; but having lost its specific properties, it was incapable of producing that change upon the human frame which is requisite to render it unsusceptible of the variolous contagion: so that it became evident a person might milk a cow one day, and having caught the disease, be for ever secure; while another person, milking the same cow the next day, might feel the influence of the virus in such a way, as to produce a sore or sores, and in consequence of this might experience an indisposition to a considerable extent; yet, as has been observed, the specific quality being lost, the constitution would receive no peculiar impression. 'Here the close analogy between the virus of small pox and of cow pox becomes remarkably conspicuous; since the former, when taken from a recent pustule, and immediately used, gives the perfect small pox to the person on whom it is inoculated: but when taken in a far advanced stage of the disease, or when (although taken early) previously to its insertion, it be exposed to such agents as, according to the established laws of nature, cause its decomposition, it can no longer be relied on as effectual. This observation will fully explain the source of those errors which have been committed by many inoculators of the cow pox. Conceiving the whole process to be so extremely simple, as not to admit of a mistake, they have been heedless about the state of the vaccine virus; and finding it limpid, as part of it will be, even in an advanced stage of the pustule, when the greater portion has been converted into a scab, they have felt an improper confidence, and sometimes mistaken a spurious pustule, which the vaccine fluid in this state is capable of exciting, for that which possesses the perfect character. During the investigation of the casual cow pox, I was struck with the idea that it might be practicable to propagate the disease by inoculation, after the manner of the small pox, first from the cow, and finally from one human being to another. I anxiously waited some time for an opportunity of putting this theory to the test. At length the period arrived. The first experiment was made upon a lad of the name of Phipps, in whose arm a little vaccine virus was inserted, taken from the hand of a young woman who had been accidentally infected by a cow. Notwithstanding the resemblance which the pustule, thus excited on the boy's arm, bore to variolous inoculation, yet as the indisposition attending it was barely perceptible, I could scarcely persuade myself the patient was secure from the small pox. However, on his being inoculated some months afterwards, it proved that he was secure.' This case inspired me with confidence; and as soon as I could again furnish myself with virus from the cow, I made an arrangement for a series of inoculations. A number of children *This boy was inoculated nearly at the expiration of five years afterwards with variolous matter, but no other effect was produced beyond a loeal inflammation around the punctured part upon the arm. were inoculated in succession, one from the other; and after several months had elapsed, they were exposed to the infection of the small pox; some by inoculation, others by variolous effluvia, and some in both ways; but they all resisted it. The result of these trials gradually led me into a wider field of experiment, which I went over not only with great attention, but with painful solicitude. This became universally known through a treatise published in June 1798. The result of my further experience was also brought forward in subsequent publications in the two succeeding years, 1799 and 1800. The distrust and scepticism which naturally arose in the minds of medical men, on my first announcing so unexpected a discovery, has now nearly disappeared. Many hundreds of them, from actual experience, have given their attestations that the inoculated cow pox proves a perfect security against the small pox; and I shall probably be within compass if I say, thousands are ready to follow their example; for the scope that this inoculation has now taken is immense. An hundred thousand persons, upon the smallest computation, have been inoculated in these realms. The numbers who have partaken of its benefits throughout Europe and other parts of the globe are incalculable: and it now becomes too manifest to admit of controversy, that the annihilation of the small pox, the most dreadful scourge of the human species, must be the final result of this practice.' We shall not adventure very deeply into the controversy which was occasioned by the discovery of the vaccine inoculation. Like every other valuable improvement, it had to struggle its way into general adoption; and though its utility is now pretty universally acknowledged, there are not wanting a few tenacious enemies who yet keep up an occasional and scattered opposition. That the Jennerian inoculation, in the most unlimited sense of the word, can be considered as an infallible preventive of the small pox, it would be foolish to imagine;— inasmuch as we have it from the discoverer's own pen, that the virus of the cow pox is liable to decomposition, and may often produce the ulcerative effects, without making sufficient impression on the constitution' to secure it against the attacks of the small pox: but that if administered by skilful hands and with the genuine virus, it is in almost every,-perhaps we may say, in every case, a security against the variolous infection, we think has been abundantly demonstrated.-In order to put our readers in possession of some of the leading facts relative to the merits of the respective modes of treatment, we shall proceed to give a concise view of the pamphlet entitled, A Comparative Sketch of the Effects of Variolous, and Vaccine Inoculation. In the first section we have a statement of the mortality occasioned by the natural small pox. It appears, that, of those infected in the natural way, one out of six are, upon an average, |