JENNÉ, a city of West Africa, formerly the capital of the Songhoi empire, now included in the French colony of Upper Senegal and Niger. Jenné is situated on a marigot or natural canal connecting the Niger and its affluent the Bani or Mahel Balevel, and is within a few miles of the latter stream. It lies 250 m. S.W. of Timbuktu in a straight line. The city is surrounded by channels connected with the Bani but in the dry season it ceases to be an island. On the north is the Moorish quarter; on the north-west, the oldest part of the city, stood the citadel, converted by the French since 1893 into a modern fort. The market-place is midway between the fort and the commercial harbour. The old mosque, partially destroyed in 1830, covered a large area in the south-west portion of the city. It was built on the site of the ancient palace of the Songhoi kings. The architecture of many of the buildings bears a resemblance to Egyptian, the façades of the houses being adorned with great buttresses of pylonic form. There is little trace of the influence of Moorish or Arabian art. The buildings are mostly constructed of clay made into flat long bricks. Massive clay walls surround the city. The inhabitants are great traders and the principal merchants have representatives at Timbuktu and all the chief places on the Niger. The boats built at Jenné are famous throughout the western Sudan.
Jenné is believed to have been founded by the Songhoi in the 8th century, and though it has passed under the dominion of many races it has never been destroyed. Jenné seems to have been at the height of its power from the 12th to the 16th century, when its merchandise was found at every port along the west coast of Africa. From this circumstance it is conjectured that Jenné (Guinea) gave its name to the whole coast (see [Guinea]). Subsequently, under the control of Moorish, Tuareg and Fula invaders, the importance of the city greatly declined. With the advent of the French, commerce again began to flourish.
See F. Dubois, Tombouctou la mystérieuse (Paris, 1897), in which several chapters are devoted to Jenné; also [Songhoi]; [Timbuktu]; and [Senegal].
JENNER, EDWARD (1749-1823), English physician and discoverer of vaccination, was born at Berkeley, Gloucestershire, on the 17th of May 1749. His father, the Rev. Stephen Jenner, rector of Rockhampton and vicar of Berkeley, came of a family that had been long established in that county, and was possessed of considerable landed property; he died when Edward was only six years old, but his eldest son, the Rev. Stephen Jenner, brought his brother up with paternal care and tenderness. Edward received his early education at Wotton-under-Edge and Cirencester, where he already showed a strong taste for natural history. The medical profession having been selected for him, he began his studies under Daniel Ludlow, a surgeon of Sodbury near Bristol; but in his twenty-first year he proceeded to London, where he became a favourite pupil of John Hunter, in whose house he resided for two years. During this period he was employed by Sir Joseph Banks to arrange and prepare the valuable zoological specimens which he had brought back from Captain Cook’s first voyage in 1771. He must have acquitted himself satisfactorily in this task, since he was offered the post of naturalist in the second expedition, but declined it as well as other advantageous offers, preferring rather to practise his profession in his native place, and near his eldest brother, to whom he was much attached. He was the principal founder of a local medical society, to which he contributed several papers of marked ability, in one of which he apparently anticipated later discoveries concerning rheumatic inflammations of the heart. He maintained a correspondence with John Hunter, under whose direction he investigated various points in biology, particularly the hibernation of hedgehogs and habits of the cuckoo; his paper on the latter subject was laid by Hunter before the Royal Society, and appeared in the Phil. Trans. for 1788. He also devoted considerable attention to the varied geological character of the district in which he lived, and constructed the first balloon seen in those parts. He was a great favourite in general society, from his agreeable and instructive conversation, and the many accomplishments he possessed. Thus he was a fair musician, both as a part singer and as a performer on the violin and flute, and a very successful writer, after the fashion of that time, of fugitive pieces of verse. In 1788 he married Catherine Kingscote, and in 1792 he obtained the degree of doctor of medicine from St Andrews.
Meanwhile the discovery that is associated with his name had been slowly maturing in his mind. When only an apprentice at Sodbury, his attention had been directed to the relations between cow-pox and small-pox in connexion with a popular belief which he found current in Gloucestershire, as to the antagonism between these two diseases. During his stay in London he appears to have mentioned the thing repeatedly to Hunter, who, being engrossed by other important pursuits, was not so strongly persuaded as Jenner was of its possible importance, yet spoke of it to his friends and in his lectures. After he began practice in Berkeley, Jenner was always accustomed to inquire what his professional brethren thought of it; but he found that, when medical men had noticed the popular report at all, they supposed it to be based on imperfect induction. His first careful investigation of the subject dated from about 1775, and five years elapsed before he had succeeded in clearing away the most perplexing difficulties by which it was surrounded. He first satisfied himself that two different forms of disease had been hitherto confounded under the term cow-pox, only one of which protected against small-pox, and that many of the cases of failure were to be thus accounted for; and his next step was to ascertain that the true cow-pox itself only protects when communicated at a particular stage of the disease. At the same time he came to the conclusion that “the grease” of horses is the same disease as cow-pox and small-pox, each being modified by the organism in which it was developed. For many years, cow-pox being scarce in his county, he had no opportunity of inoculating the disease, and so putting his discovery to the test, but he did all he could in the way of collecting information and communicating what he had ascertained. Thus in 1788 he carried a drawing of the cow-pox, as seen on the hands of a milkmaid, to London, and showed it to Sir E. Home and others, who agreed that it was “an interesting and curious subject.” At length, on the 14th of May 1796, he was able to inoculate James Phipps, a boy about eight years old, with matter from cow-pox vesicles on the hand of Sarah Nelmes. On the 1st of the following July the boy was carefully inoculated with variolous matter, but (as Jenner had predicted) no small-pox followed. The discovery was now complete, but Jenner was unable to repeat his experiment until 1798, owing to the disappearance of cow-pox from the dairies. He then repeated his inoculations with the utmost care, and prepared a pamphlet (Inquiry into the Cause and Effects of the Variolae Vaccinae) which should announce his discovery to the world. Before publishing it, however, he thought it well to visit London, so as to demonstrate the truth of his assertions to his friends; but he remained in London nearly three months, without being able to find any person who would submit to be vaccinated. Soon after he had returned home, however, Henry Cline, surgeon of St Thomas’s Hospital, inoculated some vaccine matter obtained from him over the diseased hip-joint of a child, thinking the counter-irritation might be useful, and found the patient afterwards incapable of acquiring small-pox. In the autumn of the same year, Jenner met with the first opposition to vaccination; and this was the more formidable because it proceeded from J. Ingenhousz, a celebrated physician and man of science. But meanwhile Cline’s advocacy of vaccination brought it much more decidedly before the medical profession, of whom the majority were prudent enough to suspend their judgment until they had more ample information. But besides these there were two noisy and troublesome factions, one of which opposed vaccination as a useless and dangerous practice, while the other endangered its success much more by rash and self-seeking advocacy. At the head of the latter was George Pearson, who in November 1798 published a pamphlet speculating upon the subject, before even seeing a case of cow-pox, and afterwards endeavoured, by lecturing on the subject and supplying the virus, to put himself forward as the chief agent in the cause. The matter which he distributed, which had been derived from cows that were found to be infected in London, was found frequently to produce, not the slight disease described by Jenner, but more or less severe eruptions resembling small-pox. Jenner concluded at once that this was due to an accidental contamination of the vaccine with variolous matter, and a visit to London in the spring of 1799 convinced him that this was the case. In the course of this year the practice of vaccination spread over England, being urged principally by non-professional persons of position; and towards its close attempts were made to found institutions for gratuitous vaccination and for supplying lymph to all who might apply for it. Pearson proposed to establish one of these in London, without Jenner’s knowledge, in which he offered him the post of honorary corresponding physician! On learning of this scheme to supplant him, and to carry on an institution for public vaccination on principles which he knew to be partly erroneous, Jenner once more visited London early in 1800, when he had influence enough to secure the abandonment of the project. He was afterwards presented to the king, the queen and the prince of Wales, whose encouragement materially aided the spread of vaccination in England. Meanwhile it had made rapid progress in the United States, where it was introduced by Benjamin Waterhouse, then professor of physic at Harvard, and on the continent of Europe, where it was at first diffused by De Carro of Vienna. In consequence of the war between England and France, the discovery was later in reaching Paris; but, its importance once realized, it spread rapidly over France, Spain and Italy.
A few of the incidents connected with its extension may be mentioned. Perhaps the most striking is the expedition which was sent out by the court of Spain in 1803, for the purpose of diffusing cow-pox through all the Spanish possessions in the Old and New Worlds, and which returned in three years, having circumnavigated the globe, and succeeded beyond its utmost expectations. Clergymen in Geneva and Holland urged vaccination upon their parishioners from the pulpit; in Sicily, South America and Naples religious processions were formed for the purpose of receiving it; the anniversary of Jenner’s birthday, or of the successful vaccination of James Phipps, was for many years celebrated as a feast in Germany; and the empress of Russia caused the first child operated upon to receive the name of Vaccinov, and to be educated at the public expense. About the close of the year 1801 Jenner’s friends in Gloucestershire presented him with a small service of plate as a testimonial of the esteem in which they held his discovery. This was intended merely as a preliminary to the presenting of a petition to parliament for a grant. The petition was presented in 1802, and was referred to a committee, of which the investigations resulted in a report in favour of the grant, and ultimately in a vote of £10,000.
Towards the end of 1802 steps were taken to form a society for the proper spread of vaccination in London, and the Royal Jennerian Society was finally established, Jenner returning to town to preside at the first meeting. This institution began very prosperously, more than twelve thousand persons having been inoculated in the first eighteen months, and with such effect that the deaths from small-pox, which for the latter half of the 18th century had averaged 2018 annually, fell in 1804 to 622. Unfortunately the chief resident inoculator soon set himself up as an authority opposed to Jenner, and this led to such dissensions as caused the society to die out in 1808.
Jenner was led, by the language of the chancellor of the exchequer when his grant was proposed, to attempt practice in London, but after a year’s trial he returned to Berkeley. His grant was not paid until 1804, and then, after the deduction of about £1000 for fees, it did little more than pay the expenses attendant upon his discovery. For he was so thoroughly known everywhere as the discoverer of vaccination that, as he himself said, he was “the vaccine clerk of the whole world.” At the same time he continued to vaccinate gratuitously all the poor who applied to him on certain days, so that he sometimes had as many as three hundred persons waiting at his door. Meanwhile honours began to shower upon him from abroad: he was elected a member of almost all the chief scientific societies on the continent of Europe, the first being that of Göttingen, where he was proposed by J. F. Blumenbach. But perhaps the most flattering proof of his influence was derived from France. On one occasion, when he was endeavouring to obtain the release of some of the unfortunate Englishmen who had been detained in France on the sudden termination of the Peace of Amiens, Napoleon was about to reject the petition, when Josephine uttered the name of Jenner. The emperor paused and exclaimed: “Ah, we can refuse nothing to that name.” Somewhat later he did the same service to Englishmen confined in Mexico and in Austria; and during the latter part of the great war persons before leaving England would sometimes obtain certificates signed by him which served as passports. In his own country his merits were less recognized. His applications on behalf of French prisoners in England were less successful; he never shared in any of the patronage at the disposal of the government, and was even unable to obtain a living for his nephew George.
In 1806 Lord Henry Petty (afterwards the marquess of Lansdowne) became chancellor of the exchequer, and was so convinced of the inadequacy of the former parliamentary grant that he proposed an address to the Crown, praying that the college of physicians should be directed to report upon the success of vaccination. Their report being strongly in its favour, the then chancellor of the exchequer (Spencer Perceval) proposed that a sum of £10,000 without any deductions should be paid to Jenner. The anti-vaccinationists found but one advocate in the House of Commons; and finally the sum was raised to £20,000. Jenner, however, at the same time had the mortification of learning that government did not intend to take any steps towards checking small-pox inoculation, which so persistently kept up that disease. About the same time a subscription for his benefit was begun in India, where his discovery had been gratefully received, but the full amount of this (£7383) only reached him in 1812.