Rumours of “smallpox and other infectious disease” at Cambridge in the summer of 1674[857], and at Bath in the summer of 1675[858], threatened to interfere with the studies of the one place and the gaieties of the other.

Smallpox in London in 1694: the death of the Queen.

The epidemic of smallpox in London in 1694 was made memorable by the death of the queen. On 22 November Evelyn notes, “a very sickly time, especially the smallpox, of which divers considerable persons died”; on 29 December: “the smallpox increased exceedingly, and was very mortal,” the queen having died of it the day before. Queen Mary came of a stock to which smallpox had been peculiarly fatal, a brother and sister of her father, James II., having died of it at Whitehall in 1660. Some of the particulars of her illness and death come from bishop Burnet[859], who saw her in the first days of the attack and was about the Court until the end of it; the authentic medical details are by Dr Walter Harris, one of the physicians in attendance, who published them, by leave of his superiors, in order to meet the censures passed on the doctors “by learned men at a great distance[860].”

The case of Queen Mary was one of discrete smallpox turning to the haemorrhagic form; and it had from first to last the most striking resemblance to that of her uncle, the Duke of Gloucester, in September, 1660[862]. The smallpox, says Burnet, came out, but the pustules “sunk so that there was no hope of raising them”; and in sinking they turned to livid spots or blotches. It is quite possible that the repeated doses of Venice treacle at the outset, which failed in their usual effect of inducing sweat, may have had something to do with the result, as Dr Harris certainly believed and afterwards publicly said with the leave of his superiors. But the queen, with eminent qualities of mind and heart, was not physically of good constitution. She was one of those children of James II. whom Willis had brusquely pronounced, some twenty-five years before, to be affected with mala stamina vitae; and her father’s brother, the Duke of Gloucester, who was not treated in the same way, and, by one account, not treated at all, died in exactly the same kind of haemorrhagic smallpox[863].

Circumstances of the great Epidemic in 1710.

For fifteen years after the year of Queen Mary’s death by haemorrhagic smallpox, there was comparatively little of the disease in London. In seven of the years the deaths were counted by hundreds, while the average of the whole period from 1695 to 1710, which included the years of Marlborough’s campaigns, was unaccountably low. There was a corresponding lull in the fever mortality in London; and as precisely the same kind of lull took place both in fever and smallpox during the next great war with France a century after, it may seem as if a state of war, instead of spreading infectious disease as it did in the countries where the war raged, had the effect in England of reducing it. The period of comparative immunity came to an end, both for fever and smallpox, with the great epidemic of each disease in 1710, in which year smallpox cut off 3138 in London and “great numbers in Norwich[864].” In 1714 there was another severe epidemic of smallpox in London, again in company with one of fever, and thereafter a high average for many years.

Smallpox deaths in London, 1701-1720.

The marked increase of smallpox deaths in 1710 and 1714, after an interval of low or moderate annual mortalities, caused the same cry to be raised as in the Restoration period, namely, that the medical treatment was to blame. Lynn, writing in 1714, says that many complaints were made of the destructiveness of smallpox in the epidemic four years before (1710), and of “the great want of better help, care or advice therein[865].” Woodward also ascribed the great increase of smallpox fatalities from 1710 onwards to erroneous treatment[866]. All the lives that might have been saved by better medical treatment or by more assiduous visiting of the sick would, in the then circumstances of the London populace, have made little difference to the bills of mortality. The causes that made fever so mortal in the same years were in great part the causes that made smallpox mortal, the former chiefly among those in the prime or maturity of life, the latter chiefly among the children. London had nearly reached its maximum of overcrowding; its population advanced but little for a good many years, and its mortality from all causes was so great that the numbers were only kept up by a constant recruit from the country. The necessity of doing something for the health of the poorer classes was felt, but nothing adequate was done or could be done[867]. So far as concerned the richer classes, they incurred constant danger of smallpox infection. In one of those fatal years, probably 1720, when there was smallpox among persons of quality in London, the Duchess of Argyll wrote to the Countess of Bute, to congratulate her on the birth of a daughter and on having two fine boys in her family already, “and he that has had the smallpox as good as two, so mortal as that distemper has been this year in town was never known[868].”

The domestics also of great houses frequently caught smallpox and spread it, a trouble which gave occasion at length, in 1746, to the first Smallpox Hospital for the admission of such of them as brought subscribers’ letters. Before that it had been the practice of the rich to send their domestics to private houses kept by nurses[869].

It was in these circumstances, and for the benefit of the upper classes and their domestics, that a project of getting through smallpox on easy terms was brought to the notice of London society in 1721.

Inoculation brought into England.

The first that was heard in England of engrafting the smallpox was through a communication by Dr Timoni, a Greek of Constantinople, to Dr Woodward, Gresham professor of physic, who had the paper printed in the Philosophical Transactions of the Royal Society[870]. After a statement that “the Circassians, Georgians and other Asiatics” had brought the practice to Constantinople, and that it had been followed there for forty years by “the Turks and others” (statements never confirmed but on inquiry contradicted by those who knew), he proceeds to matters more within his own competence. During these eight years past “thousands” of subjects have been inoculated, and the value of the practice has now been put beyond all suspicion and doubt. The practice is to take fluid smallpox matter from the pustules of a discrete case of the natural disease, and convey it warm in a stopped phial to the scene of inoculation. A few punctures with a three-edged surgeon’s needle are made in any of the fleshy parts (but preferably over the muscles of the arm or forearm) until the blood comes; a drop of the fluid matter of smallpox is then to be mixed with the blood, and the inoculated part to be protected by a walnut shell bound over it. The symptoms that follow are very slight, some being scarce sensible that they are ill. The pocks that ensue are for the most part distinct, few, and scattered; commonly ten or twenty break out; now and then the patient may have only two or three; few have a hundred. The matter is hardly a thick pus, as in the common sort, but a thinner kind of sanies. There are some in whom no pustules appear except at the points of insertion, where purulent tubercles arise; yet these have never had the smallpox afterwards in their whole lives, though they have consorted with persons having it. On one occasion fifty were inoculated together, and of these four developed smallpox which was nearly confluent; but there was a suspicion that they must have been already infected by contagion. Timoni had never observed any mischievous accident from this incision hitherto; reports of such had sometimes spread abroad among the vulgar, “yet having gone on purpose to the houses whence such rumours have arisen I have found the whole to be absolutely false.” But, to keep nothing back, he will mention two fatalities of children inoculated; both of them were cases of hereditary lues with marasmus, and it was about the fortieth day from their inoculation that death ensued. The rest of Timoni’s paper is printed in the original Latin, being devoted to a theory of engrafting which afterwards passed current:—one attack of smallpox secures from a second, a mild attack serves as well as a severe, as also in the natural way, the reason being that smallpox, in whatever degree, causes a fermentation of the mass of the blood.

A year after this, in 1715, there was published in London An Essay on External Remedies, of which the 37th chapter was “Of the Variolae or Small Pox, the manner of ingrafting or giving them, and of their Cure.” The author was Peter Kennedy, Chir. Med., a Scot of good but impoverished family, who had spent several years in various parts of Europe visiting the schools of medicine and surgery, and had found his way to Constantinople[871]. His account of the engrafting of smallpox, which he had seen or heard of there, differs somewhat from that of Timoni, whom he just refers to: “Dr Timoni, a Grecian who resides there, had taken or followed this same method with his two sisters a little before my arrival at Constantinople.”

Kennedy says that engrafting the smallpox was practised in the Peloponnesus or Morea, “and at this present time is very much used both in Turkey and Persia, where they give it in order to prevent its more severe effects by the early knowledge of its coming; as also probably to prevent them being troubled with it a second time.” In Persia, however, the smallpox was taken internally in a dose of dried powder. In Constantinople the matter was inserted at scarifications upon the forehead, wrists, and ankles. After eight or ten days the smallpox came forward in a kindly manner, and not nearly so numerous as if naturally taken. “The greatest objection commonly proposed is, whether or not it hinders the patient from being infected a second time. But, in answer to this, it is advanced that we do rarely or never find any to have been troubled with this distemper twice in the same manner or the same fulness of malignity”—i.e. we rarely find this in the natural way.

Kennedy’s object was, not to recommend the engrafting of smallpox in England, but to show how easily distempers or contagions, “as well as medicines,” may be communicated to the blood from the surface of the body: “and this is more confirmed by some of the country people in Italy, in the more remote parts from towns, so also in some parts of the highlands of Scotland, where they infect their children by rubbing them with a kindly pock, as they term it.”

Meanwhile Timoni’s essay in the Philosophical Transactions had stirred up Sir Hans Sloane to make farther inquiries[872]. He applied to the British consul at Smyrna, Dr Sherrard, who was fortunately able to get information at first hand from an old Smyrna colleague, Dr Pylarini, consul for Venice, who had practised inoculation at Constantinople in the first years of the century. Pylarini, who had retired to Venice, was induced to draw up an account of what he knew of the beginnings and original methods of engrafting, which was printed at Venice, with a dedication to Sherrard, in 1715, and at once copied into the Philosophical Transactions[873]. This, the most trustworthy account of the Constantinople practice, ignores the earlier essay of Timoni altogether.

Pylarini carries the authentic history of the practice at Constantinople back to the year 1701. Its history before that was obscure; but it is most certain, he says, that it began in Greece, more particularly in Thessaly, and crept gradually from place to place until it reached Constantinople, where it attracted little notice for several years, being rarely practised and only among the lower class. A noble Greek having spoken of it to him in 1701, with a view to the protection of his children from the epidemic then raging, Pylarini had to confess his entire ignorance of it, but being at the Greek’s house four days after he there met a Greek woman who expounded the practice clearly in detail and gave him many instances of persons who had gone through it safely. Pylarini inquired into some of these cases and found them to be genuine; but in that great city he could not search them all out. Soon after this interview, the woman came and operated on the four children of the rich Greek, of whom the three younger had a very mild disease, but the eldest a severe attack, which nearly cost her life. Many other rich Greek families followed suit, so that, says Pylarini in 1715, “every one wishes to have the advantage of transplantation.” He adds, however, that “the Turks have hitherto neglected it.” He confirms Timoni in saying that the pocks raised by transplantation were nearly always of the distinct kind and few in number—ten to twenty or thirty, rarely a hundred, very rarely two hundred,—although he does not reach Timoni’s minimum of “two or three,” or the pustules only at the punctured spots.

These accounts from Constantinople, printed in London in 1714, 1715 and 1716 were regarded, says Douglass, “as virtuoso amusements[874]” until the spring of 1721, when inoculation began to be tried tentatively in London, and in a bold and confident way during the very same weeks at Boston, New England.

Dr Pitcairn, of Edinburgh, had received an account of inoculation from Bellini, an Italian physician, who had read Pylarini’s essay. Douglass says that Pitcairn “was very fond of it, but could not persuade himself to venture it in practice[875].” Sometime in March, 1721, one à Castro had issued in London a pamphlet on inoculation, full of inaccuracies and of no moment[876]. In a lecture on the plague given at the College of Physicians on the 17th of April, 1721, Dr Walter Harris made a passing reference to the Constantinople practice of engrafting smallpox[877]; and shortly after that, or shortly before, the Lady Mary Wortley Montagu set about having her younger child inoculated in London, her elder child having been inoculated at Constantinople three or four years before. This lady had, in 1717, accompanied her husband as ambassador to the Porte, where the embassy remained about a year. During her residence at Pera she heard of the Greek practice of engrafting or transplanting the smallpox; the French ambassador had said in pleasantry to her: “They take the smallpox here by way of diversion, as they take the waters in other countries.” According to her information, there was a set of old women who made it their business to perform the operation every autumn, in the month of September, when the great heat is abated. People send to one another to know if any of their family has a mind to have the smallpox; they make parties for this purpose, and when they are met (commonly fifteen or sixteen together) the old woman comes with a nut-shell full of matter. Every year thousands undergo the operation (but according to the information of the British embassy in 1755 not more than twenty in a year, which may perhaps mean that it had fallen into disuse[878]). There is no example of anyone that has died of it. She intended to have it performed upon her little son, and had patriotic visions of bringing “this useful invention” into fashion in England. Accordingly her boy, aged five, was inoculated in March, 1717/18, by a Greek woman, under the direction of Maitland, a Scots surgeon who attended the embassy. The child suffered very little inconvenience and, according to Maitland, “had about an hundred pox all upon his body.”

Lady Mary returned to London in 1718; but it was not until some three years after, in the spring of 1721, that she stirred the matter again. Whether it was that she herself was the cause of the talk about inoculation in London in April, 1721, or that she merely had the subject brought back to her mind by the essay of à Castro, the lecture by Harris, or by what others were saying, she sent sometime in April for Maitland, who had assisted at the inoculation of her elder child at Pera, with a view to having the operation done on the younger, who was now four or five years old. In a week or two Maitland found suitable smallpox matter and engrafted the child on both arms; on the tenth night she was a little feverish, but the smallpox began to appear next morning and in a few days she was perfectly recovered. Three physicians of the College visited the case, as well as several ladies and other persons of distinction. One of those physicians, Dr Keith, resolved to have a boy of his own, aged six, engrafted, which was done by Maitland on both arms on the 11th of May, 1721, five ounces of blood having been drawn before the operation.

Among Lady Mary’s intimates was the Princess of Wales, who became interested in the project for the sake of her own children[879]. She proposed to the king (George I.) that he should remit the capital sentence of six Newgate felons on condition that they would submit to be inoculated. The king consulted Sir Hans Sloane, who applied to Dr Terry of Enfield, formerly in practice at Constantinople. Terry’s report was that not more than one in eight hundred had died from the effects of inoculation in Turkey. The upshot was that the six Newgate convicts, three men and three women, were inoculated by Maitland on the 9th of August, 1721, in the presence of several eminent physicians, surgeons, Turkey merchants, and others. The matter was inserted on both arms and on the right leg of each, and the insertion was repeated on the arms of five of them three days after. Dr Mead, having heard that the Chinese procured smallpox by stuffing the matter up their noses, got a pardon for a seventh convict under sentence of death, a young woman, on condition that she would submit to a pledget of cotton dipped in smallpox matter being inserted in her nostril: it produced, besides a fair smallpox, much severe pain along the Schneiderian membrane and the frontal sinuses, and was not thought a satisfactory experiment. The trial upon the other six was reassuring; they all escaped with the slightest possible eruption; “the most that anyone had was sixty pustules.”

The next step was on the part of the Princess of Wales, who procured the inoculation of six charity children of the parish of St James’s. Four of them had smallpox “very favourably”; one did not have it at all, “having evidently had the smallpox before”; and the sixth had not only the prolonged effects of inoculation, but also an attack of the natural smallpox, of a favourable kind, eleven weeks after. This experiment was followed by the inoculation of five more hospital children, from eight to fourteen weeks old, of whom three had no effects, their bodies being “morbid.” The Princess of Wales was at length resolved in April, 1722, to run the risk of the operation on her two daughters, the princess Amelia, aged eleven, and the princess Caroline, aged nine, being urged by the fact that another daughter, the princess Anne, afterwards princess royal of Orange, had just had the natural smallpox so dangerously that Sloane feared for her life. The inoculations were done on the 19th of April, by serjeant-surgeon Amyand under the direction of Sir Hans Sloane. What passed between that physician and the king shows at once the apprehension of danger from a novel operation and the temper in which it was undertaken:

The news of the successful inoculation of the two princesses had hardly time to create a vogue for the practice, when there came word, in the same month of April, of the death by inoculation of the Earl of Sunderland’s son, aged two and a half, and of Lord Bathurst’s footman, aged nineteen.

Meanwhile, in the autumn of 1721, Maitland had gone down to Hertford, where smallpox would seem to have been more rife than elsewhere, and had done several inoculations. In the family of a Quaker, near Hertford, an infant of two and a half years developed no more than twenty pustules, which lasted only three or four days; but six domestics of the house, four men and two maids, “who all in their turn were wont to hug and caress this child whilst under the operation and the pustules were out upon her” (Maitland), caught natural smallpox in varying degrees of severity, some of them having a narrow escape, while one of the maids died.

The question that people were really anxious about was the immediate risk to the inoculated; and as there were occasional fatalities, especially to the age of childhood, inoculation made little progress. In the first year of its trial in England it was done on the greatest scale by Dr Nettleton, of Halifax, whose practice remains for more particular notice. Apart from his cases, which numbered sixty-one, the following are all that were known in England from the month of April, 1721, to the end of 1722[880]:

The inoculations in all England in 1723 reached the considerable total of 292; but in 1724 they were no more than 40, being distributed among the various operators as follows:

In the next two years, 1725-26, Amyand and Maitland had respectively 66 and 37 cases in London, the other known cases in London being 30. Maitland had also 16 cases in Scotland. Sir Thomas Lyttelton had 4 at Hagley. All the known cases in those two years, including Nettleton’s at Halifax, came to 256, with four deaths of somewhat conspicuous persons. In 1727 the inoculations fell to 87, and in 1728 to 37. The total in eight years was 897, with 17 deaths. For the next ten or twelve years none were heard of in Britain. The check, however, was only temporary. The practice revived, extended among the rich, at length reached the common people in some counties, and gave rise to important developments of scientific doctrine. The greater these developments the more interesting the origins, which we shall now examine.

The popular Origins of Inoculation.

Six years before the Greek inoculation was tried in London, Kennedy, the travelled Scot, had compared the Constantinople practice with one that he knew of in his native country: “So also in some parts of the highlands of Scotland they infect their children by rubbing them with a kindly pock.” This indigenous Scots practice was confirmed by Professor Monro, the first, of Edinburgh, in 1765:

And, to make it clear that this was not the same as the method afterwards used of procuring the smallpox, he adds that the latter was not known in Scotland until Maitland introduced it, in 1726[881]. In Wales the curious practice of buying the smallpox was found to be indigenous[882]. One young woman in a village near Milford Haven testified in 1722 that, some eight or nine years before, she had bought twenty pocky scabs of one in the smallpox, and had held them in her hand, with the result that she sickened with the infection in ten or twelve days and had upwards of thirty large pustules in her face and elsewhere—at least ten more than she had bargained for. A schoolboy of Oswestry, who had since become an attorney and must have known the nature of an affidavit, bought, as he positively affirmed, for three-pence of a certain lady twelve pustules of smallpox (at a farthing each), and rubbed the matter into his hand with the back of his pocket-knife; a sore remained on the hand as well as pockpits in his face.

There was nothing remarkable in these methods of procuring smallpox except an occasional element of superstition or freak. It was not unusual in England for educated persons to let smallpox go through all their children after it had attacked one of them, just as it is regarded an economy by many to have done with the measles. On 15 September, 1685, Evelyn travelling to Portsmouth in the company of Pepys, stopped to make a call at Bagshot at the house of Mrs Graham, a former maid of honour to the queen. “Her eldest son was now sick of the smallpox, but in a likely way to recover, and others of her children ran about and among the infected, which she said she let them do on purpose that they might whilst young pass that fatal disease she fancied they were to undergo one time or other, and that this would be for the best.” It would be for the best because children from five to ten or fifteen (the older writers said even infants) ran far less risk from the attack than at the higher ages, and seldom died of it.

Similar means of procuring smallpox for children were used in other countries. La Motraye, who rode through the Caucasus in 1712, was told that children, to give them the smallpox, were placed in the same bed with one who had it, the mothers sometimes carrying them a whole day’s journey to any village where they heard of someone being attacked. He professes also to have seen a child of four inoculated with smallpox matter at five places (the region of the heart, the pit of the stomach, the navel, the right wrist and the left foot) by an old woman who used “three needles tied together[883].” The idea of barter was widely spread in those practices of procuring smallpox on favourable terms. We have seen that the Welsh had it. Bruce found it in his travels to the sources of the Nile[884]. African negroes are known also to have carried with them to the West Indies the practice of “buying the yaws,” which is also a contagious and inoculable disease of the skin. The earliest medical notices of buying the smallpox come from Poland in 1671 and 1677. A case having been published in the Miscellanea Curiosa of the Imperial German Academy, in which a quartan ague was alleged to have been got rid of by transferring it to a brute animal, Dr Vollgnad, of Warsaw wrote: “There is a similar superstition not uncommon among our nurses, who instruct the children under their charge to buy for a few farthings a certain number of pocks from one infected with the smallpox, in the belief that those who purchase that disagreeable commodity will be affected with a more scanty eruption and will be the sooner freed from the disease and with the less risk[885].” Six years after, Dr Simon Schultz, of Thorn, physician to the king of Poland, wrote that the same practice of buying the smallpox obtained also in that part of Poland: “What I have first to remark,” he says, “is that, in most cases if not in all, those infants that buy of the infected (whether in their proper persons or through others), while they may have few pocks, yet fall into a more serious illness than otherwise (gravius reliquis decumbant): which I remember to have happened to my younger brother Johannes, to say nothing of others[886].”

These early references to buying the smallpox were made à propos of the 17th century practice of sympathetic transference of disease from one to another, or from man to brute, or to plants, stones, holes in the ground, etc.[887], and were published as instances of “a similar superstition.” The case of a transferred ague which called them forth had been sent to the Curiosa of the Academy by Thomas Bartholin, the celebrated anatomist of Copenhagen. Ten years before, he had written in the Theatrum Sympatheticum Auctum[888] (to which also Dr Sylvester Rattray, of Glasgow, and Sir Kenelm Digby contributed): “I disclose a great mystery of nature. The transplantation of diseases is a stupendous remedy, by means of which the ailments of this or that person are transferred to a brute animal, or to another person, or to some inanimate thing”—various methods being instanced. He returned to the subject in 1673 under the title of the Transplantation of Disease, the name by which Pylarini first described the engrafting of smallpox[889]. It was the transfusion of blood, a foible of the time, especially at the Royal Society in London, which set Bartholin to his second essay. He expected that health, in the one case, or disease in the other, might be transplanted to another’s veins with the blood. It would be an incomparable addition to the amenities of life to be able to draw off in a syringe the diseased blood of a familiar friend and bring it to a better coction by one’s own juices[890].

Bartholin discovered the germ of these scientific developments in the scape-goat of the Israelites and in the miracle of the swine of Gadara[891]. In his own doctrine of transplantation, others in turn have found the germ of inoculation, Pylarini having actually adopted the 17th century name, with the proviso that the transplantation of smallpox was not sympathetic but res vera mera pura. The older idea of transplanting smallpox was to get rid of it. “Some persons in the smallpox,” says Slatholm, of Buntingford, in 1657, “keep a sheep or a wether beside them in the chamber, those animals being apt to receive the envenomed matter and to draw it to themselves[892].” The developments of folk-lore are erratic; one thing leads to another, but not necessarily in a logical sequence. Transference had somehow become the inoculation which Pylarini first found in the practice of a woman from the Morea or from Bosnia, being still in its superstitious stage. The woman drew blood and rubbed the smallpox matter into the bleeding points; but whether she did so with a physiological or a symbolical intent we shall probably never know. She told Dr Le Duc[893], who submitted to inoculation at her hands, that she had received the secret from the Virgin; during the operation she muttered prayers to the Virgin, and, on finishing it, requested an oblation of two wax candles to be sent to the shrine of the Virgin her patroness in Thessaly. She pricked the skin of the face at the four points which are touched in making the sign of the Cross, and at the points of the hands and feet which are pierced by the nails in the Crucifix. Voltaire says that Lady Mary Wortley Montagu’s chaplain objected to inoculation because it was an un-Christian practice. He must have been strangely ill-informed if he did so; for at Constantinople it was practised by the Christians only and not at all by the Mussulmans, who, by Kennedy’s account, were somewhat doubtful of its utility.

Pylarini and Timoni very properly dropped the symbolism of the Greek woman, and inserted the matter at any convenient spot, choosing usually the skin of the forearm. Therewith they took the practice under scientific protection. At the same time Pylarini was careful to explain that this transference of disease, although he called it by Bartholin’s old name of “transplantation,” was a real thing, and in no way akin to the sympathetic or magnetic transference whose name it bore. A real thing it undoubtedly was: a visible effect did follow in most cases—some ten, or twenty or thirty watery pimples on the skin. The effect being thus real, Pylarini and Timoni laid down at the outset the doctrine that the smallpox matter inserted in minute quantity was a ferment, which produced an ebullition in the mass of the blood. The common people, who had been procuring the smallpox for their children in other ways than by puncture and insertion, also knew that the transplanting was a real thing: it was smallpox, and nothing else, that they designed to procure, peradventure it might be mild smallpox.

While Pylarini used the name of Transplantation, Timoni used the name of Inoculation. Both names were figures of speech taken from the gardener’s art. Inoculation, or ineying, was a form of grafting, the taking of the “eye” or resting-bud of one kind of fruit-tree and fixing it upon the stock of another kind. The effect of a graft upon a fruit-tree is one of the most remarkable in nature: the incorporation of a bud from a nearly allied species at a particular part of the stock causes the whole tree to assume some characters of the other tree, the change being greatest in the fruit. An effect at once so real, so useful, and so familiar could not fail to take hold of the imagination. Accordingly we find the ineying or grafting of trees used in a correct figure, as in Hamlet’s “for virtue cannot so inoculate our old stock but we shall relish of it.” Between a fruit-tree modified as to its fruit by the permanent incorporation of a strange shoot, and an animal body infected of purpose with diseased matter, there is no very exact analogy. Figurative names, as well as metaphors, are apt to be mixed ideas. Correct science avoids the one vice, as correct style avoids the other. Transplantation had in any case too many fanciful associations to be retained as the name for the new practice in smallpox; inoculation, on the other hand, was still unspoiled as a medical term, while its wonderful effects were obvious in the familiar art of the gardener.

In all the developments or modifications of this practice, the intention was still to procure the smallpox by art. The idea of antidote or counter-poison did not enter into it at all. Yet the idea of a counter-poison was quite familiar, as in the following passage from a medical writer of the time of James I.[894]: