the floating force of twenty-five thousand men. In this war, the enlightened and educative measures of the Japanese reduced the deaths due to disease to onequarter of those due to battle. Thanks to the adoption of scientific methods, the incidence of disease in the British army during the great European War has been far lighter than in any previous campaign. The magnificent results achieved by attention to the essential principles of sanitation and preventive medicine have disposed-we hope for ever-of the old saying, "Disease, not battle, digs the soldier's grave." The health of the British Expeditionary Force is not only safeguarded by sanitary precautions, but also protected against typhoid fever by a treatment of inoculation instituted by Sir Almroth Wright. The success of these methods is little short of marvellous. Deaths of British soldiers from typhoid are much less in proportion than in any preceding war, and men fully protected by two inoculations escape punishment by the disease almost without exception.

The same principles of preventive medicine are applicable with no less success to civil life. What is true of typhoid, cholera, dysentery and malaria, is equally true of smallpox, tuberculosis, yellow fever, scurvy, rabies, plague and diphtheria, and is true also of numerous other common illnesses; applicable, therefore, to the poverty and distress which result from them.

Smallpox was formerly looked upon as practically unavoidable by members of the human family. People used to advertise for servants who had got over smallpox in much the same way as we now inquire, before purchasing a dog, whether it has had distemper. The difficulty of getting through life without smallpox was expressed in a popular saying very current in Germany in the eighteenth century; von Pocken und Liebe bleiben

nur wenige frei-from smallpox and love few remain In his History of England, Macaulay, referring to the death of Queen Mary from the disease in 1694 says:

That disease over which science has since achieved a succession of glorious and beneficial victories was then the most terrible of all the ministers of death. The havoc of the plague had been far more rapid; but plague had visited our shores only once or twice within living memory, and the smallpox was always present, filling the churchyards with corpses, tormenting with constant fears all whom it had not yet stricken, leaving on those whose lives it spared the hideous traces of its power, turning the babe into a changeling at which the mother shuddered, and making the eyes and cheeks of the betrothed maiden objects of horror to the lover. T. B. Macaulay.

For the different conditions which exist in civilised countries to-day, and for the fact that the fear of smallpox has become almost as remote as the fear of leprosy, we have chiefly to thank Edward Jenner (1749-1823)— the apostle of vaccination. Others had vaccinated before Jenner, but he was the first to rouse the civilised world to take an active interest in the subject. Among medical men of all nationalities his name is held in the highest reverence. Jenner, Pasteur and Lister form a triumvirate that has given the human race reason to rise up and call it blessed.

The value of vaccination as a protection against smallpox was established by Jenner in 1796; the principle of the method of protective inoculation was used by Pasteur in conferring immunity of animals from anthrax eighty-five years later; and Lister was led to introduce the system of antiseptic surgery by the study of Pasteur's investigations. Jenner opened the door to a new realm of remedies for disease; and we are only now beginning to realise how vast it is and what possibilities it offers for the future.

Jenner was in his teens and in the first stage of his medical education at Sodbury, Gloucestershire, when his attention was directed to the subject of protection against smallpox. A young girl came there for advice, and on smallpox being mentioned she exclaimed, “I cannot take that disease, for I have had cow-pox." She, like other milkmaids in Gloucestershire and elsewhere, had discovered for themselves that cow-pox was a safeguard against smallpox; but it required the insight and patient labour of Jenner to transform a piece of folklore into a scientific truth, and make the medical profession all over the world receive it as such.

When Jenner went to London, at the age of twentyone, and was entered as a student at St. George's Hospital, he mentioned this belief to John Hunter, who gave his pupil this excellent piece of advice: "Do not think, but try; be patient, be accurate." On returning to his native town of Berkeley to settle down into country practice as a physician, the belief of the young girl at Sodbury, and Hunter's wise words, were ever constant in his mind. To get at the truth of this opinion was his great object; but it was not until 1780 that he felt sufficient confidence to communicate to a friend his ideas on the subject of propagating the protective cowpox from one individual to another, and so ultimately staying the plague of smallpox.

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Gardiner," said Jenner, "I have entrusted a most important matter to you, which I firmly believe will prove of essential benefit to the human race. I know you, and should not wish what I have stated to be brought into conversation, for should anything untoward turn up in my experiments, I should be made, particularly by my medical brethren, the subject of ridicule, for I am the mark they all shoot at."

Jenner continued his experiments for another sixteen years before he performed his first inoculation with cow-pox on May 14th, 1796, the subject being a boy, about eight years of age. The boy was afterwards inoculated for the smallpox, and as Jenner predicted, no disease followed. A means of protecting the human race against its greatest scourge had been discovered, and Jenner redoubled his efforts to establish its efficacy. . He vaccinated all the poor in the neighbourhood of Berkeley gratuitously, and the success of the method of inoculation soon became widely known. He vaccinated his own son on three separate occasions, and prejudice against inoculation with cow-pox began to be overcome when two ladies of title-Lady Ducie and the Countess of Berkeley-submitted their children to it.

If Jenner had kept the secret of his discovery to himself, he could have made an immense fortune from it, but he imparted it to the public, and suffered great loss of time and money in answering inquiries which reached him from all parts of the world. He made known his discovery as soon as he had convinced himself of its value, and never for a moment did he hesitate as to whether he might not be a richer man by keeping his information to himself.

It is scarcely necessary to add that the discovery did not escape the fate which commonly awaits originality. Jenner's views were opposed and misrepresented, the caricaturists of the period drew persons with horns and cows' heads to suggest what might be expected from vaccination, and sermons were preached to show its wickedness. Nothing could, however, prevent the spread of a method which relieved every household of its greatest terror. Marks of distinction soon began to be showered upon the scientific St. George who had rid

mankind of the dragon of smallpox that had demanded tens of thousands of victims annually. With the Emperor Napoleon, Jenner was a great favourite. On one occasion Napoleon was about to refuse a petition from Jenner to allow two friends to return to England, when Josephine reminded him that the petition was from the discoverer of vaccination. Ah," said the Emperor, Jenner, we can refuse nothing to that man.'

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In recognition of the national value of vaccination, the House of Commons voted Jenner a grant of £10,000 in 1802, and five years later a further grant of £20,000 was made to him, the intervening time having strengthened the general opinion as to the efficacy of vaccination and as to its great benefit to the nation at large. Competent authorities would not now claim that a single inoculation with vaccine lymph is a perfect antidote against smallpox throughout life, but only that it confers a high degree of protection against the disease. Absolute immunity cannot be ensured in all cases because of individual differences of the blood and tissues of the human body; yet with this reservation the practice of vaccination has been completely justified. We owe our deliverance from the fear of smallpox not so much to improved sanitation, or to a natural decline of the disease or acquired immunity from it, as to the protective principle introduced by Jenner. The progress of preventive medicine depends largely upon the application of this principle, which has proved to be of even greater biological value than was anticipated by Jenner or the physicians of his day.

Many diseases of animals, as well as those of man, are now controlled or conquered by the application of scientific principles. Before science showed the nature of anthrax, and provided the remedy, many thousands