Harvey was as indefatigable a labourer as any we have named. He spent not less than eight long years of investigation and research before he published his views of the circulation of the blood. He repeated and verified his experiments again and again, probably anticipating the opposition he would have to encounter from the profession on making known his discovery. The tract in which he at length announced his views, was a most modest one, - but simple, perspicuous, and conclusive. It was nevertheless received with ridicule, as the utterance of a crack-brained impostor. For some time, he did not make a single convert, and gained nothing but contumely and abuse. He had called in question the revered authority of the ancients; and it was even averred that his views were calculated to subvert the authority of the Scriptures and undermine the very foundations of morality and religion. His little practice fell away, and he was left almost without a friend.
This lasted for some years, until the great truth, held fast by Harvey amidst all his adversity, and which had dropped into many thoughtful minds, gradually ripened by further observation, and after a period of about twenty-five years, it became generally recognised as an established scientific truth.
The difficulties encountered by Dr. Jenner in promulgating and establishing his discovery of vaccination as a preventive of small-pox, were even greater than those of Harvey. Many, before him, had witnessed the cow-pox, and had heard of the report current among the milkmaids in Gloucestershire, that whoever had taken that disease was secure against small-pox. It was a trifling, vulgar rumour, supposed to have no significance whatever; and no one had thought it worthy of investigation, until it was accidentally brought under the notice of Jenner. He was a youth, pursuing his studies at Sodbury, when his attention was arrested by the casual observation made by a country girl who came to his master's shop for advice. The small-pox was mentioned, when the girl said, "Ican't take that disease, for I have had cow-pox." The observation immediately riveted Jenner's attention, and he forthwith set about inquiring and making observations on the subject. His professional friends, to whom he mentioned his views as to the prophylactic virtues of cow-pox, laughed at him, and even threatened to expel him from their society, if he persisted in harassing them with the subject. In London he was so fortunate as to study under John Hunter, to whom he communicated his views. The advice of the great anatomist was thoroughly characteristic: "Don't think, but TRY; be patient, be accurate." Jenner's courage was supported by the advice, which conveyed to him the true art of philosophical investigation. He went back to the country to practise his profession and make observations and experiments, which he continued to pursue for a period of twenty years. His faith in his discovery was so implicit that he vaccinated his own son on three several occasions. At length he published his views in a quarto of about seventy pages, in which he gave the details of twenty-three cases of successful vaccination of individuals, to whom it was found afterwards impossible to communicate the small-pox either by contagion or inoculation. It was in 1798 that this treatise was published; though he had been working out his ideas since the year 1775, when they had begun to assume a definite form.
How was the discovery received? First with indifference, then with active hostility. Jenner proceeded to London to exhibit to the profession the process of vaccination and its results; but not a single medical man could be induced to make trial of it, and after fruitlessly waiting for nearly three months, he returned to his native village. He was even caricatured and abused for his attempt to "bestialize" his species by the introduction into their systems of diseased matter from the cow's udder. Vaccination was denounced from the pulpit as "diabolical." It was averred that vaccinated children became "ox-faced," that abscesses broke out to "indicate sprouting horns," and that the countenance was gradually "transmuted into the visage of a cow, the voice into the bellowing of bulls." Vaccination, however, was a truth, and notwithstanding the violence of the opposition, belief in it spread slowly. In one village, where a gentleman tried to introduce the practice, the first persons who permitted themselves to be vaccinated were absolutely pelted and driven into their houses if they appeared out of doors. Two ladies of title - Lady Ducie and the Countess of Berkeley - to their honour be it remembered - had the courage to vaccinate their children; and the prejudices of the day were at once broken through. The medical profession gradually came round, and there were several who even sought to rob Dr. Jenner of the merit of the discovery, when its importance came to be recognised.
Jenner's cause at last triumphed, and he was publicly honoured and rewarded. In his prosperity he was as modest as he had been in his obscurity. He was invited to settle in London, and told that he might command a practice of 10,000L. a year. But his answer was, "No! In the morning of my days I have sought the sequestered and lowly paths of life - the valley, and not the mountain, - and now, in the evening of my days, it is not meet for me to hold myself up as an object for fortune and for fame." During Jenner's own life-time the practice of vaccination became adopted all over the civilized world; and when he died, his title as a Benefactor of his kind was recognised far and wide. Cuvier has said, "If vaccine were the only discovery of the epoch, it would serve to render it illustrious for ever; yet it knocked twenty times in vain at the doors of the Academies."Not less patient, resolute, and persevering was Sir Charles Bell in the prosecution of his discoveries relating to the nervous system.
