INTRODUCTION. PREFATORY. THERE are few matters among educated people upon which opinion is so absolute and so ill-informed as vaccination. They will tell you it has stopped smallpox and does no harm, and if you venture to question either assertion you are set down as an abettor of "those ignorant and fanatical anti-vaccinators." If undeterred you inquire when smallpox was stopped, and which is the harmless variety of vaccination, you will probably be told that these are medical questions, whilst the facts are indisputable; the answer running in the line of Old Kaspar's to Little Peterkin, inquisitive as to the good of Blenheim Why that I cannot tell, said he, I am not complaining of this attitude of mind. We all accept more or less on bare authority. In the multiplicity and unsearchableness of knowledge, it is unavoidable. Some years ago a venerable friend urged me to write against vaccination, which, he said, was working endless mischief to the public health. He would have the book published, and provide whatever was requisite for my satisfaction. I pleaded prior engagements, and turned the conversation, thinking how sad it was that one so good, and, in other respects, so enlightened should be subject to so strange an illusion-I, then, taking vaccination on trust as one of the numerous blessings conferred upon mankind in the course of the present century. I am therefore disposed to make large allowance for the credulous attitude of the public toward vaccination whilst at the same time insisting on its correction; and for this reason especially, that vaccination is no longer a matter of private concern. We are free to entertain what notions we please, but if we proceed to enforce them on unbelievers, we cannot complain if we are required to answer for our aggression or encounter rough usage. Enforced by the law of England, vaccination is related to the life and intelligence of every citizen, and it is consequently vain to claim for it exemption from vulgar discussion. Apart from its compulsory infliction, vaccination might be and remain an esoteric rite, the very mystery of mysteries; but with compulsion the privilege of sanctity is impossible. VARIOLATION. It has been said that beliefs and observances in themselves most irrational wear a different aspect when viewed in the light of their origin and history. It is so with vaccination. Had it come upon the world as we know it, with failure and disaster, equivocation and apology, rejection would have been inevitable; but when we turn to the past we discover that our damnosa hæreditas has a tradition that goes far to account for, if not to excuse, the folly which remains. Vaccination was the successor of Inoculation (or, more precisely, Variolation), entering into a possession already acquired in the human mind. It had been observed from of old that some forms of disease rarely recur in the same person in a lifetime; and thus when scarlet fever, or measles, or smallpox broke out in a family, it was considered prudent to let the disease have its course, and thereby obtain immunity from fear of future infection. It was this confidence, that smallpox once undergone was finally disposed of, that was the justification of the practice of inoculating the disease when introduced from the East in the first quarter of last century. Inasmuch, it was argued, as none can have smallpox more than once, why not induce it artificially, and pass through the ill ness at a convenient season? But Nature, though compliant, does not always accept the course we ingeniously prescribe for her. Smallpox as naturally developed (so to speak) is a crisis of impurity in the blood, and if the requisite conditions are absent, it cannot be adequately excited. Hence variolation was an uncertain and hazardous operation. It took with some and was indistinguishable from an attack of ordinary smallpox; it took partially, or not at all with others; and the operation was frequently followed by malaise, disorders of the skin, and grave constitutional derangements. Nor were the variolated secure from smallpox. They occasionally had smallpox with their neighbours, and then it was said, "There must have been some mistake about the "inoculation; for it is impossible that anyone can be suc"cessfully inoculated and have smallpox." Further, the variolated, while labouring under the induced malady, conveyed the disease to their attendants and visitors; and thus smallpox was propagated by the means intended to avert it. THE PRECURSOR OF VACCINATION. At the close of last century, variolation had become the custom of the upper and middle classes of England. The trouble and the peril were disliked, but were accepted in the name of duty. The variolation of their children. was an anxiety that weighed like lead on the hearts of affectionate parents; and glad and grateful they were when the operation was accomplished without serious mishap. Patients designed for variolation were dieted, purged, and bled; and smallpox from sufferers of sound constitution was diligently inquired for. Mild smallpox was in great demand and was propagated from arm to arm. When Dr. Dimsdale operated on the Empress Catharine he did not venture to convey smallpox direct to the imperial person. He looked out a case of "benign smallpox" with which he inoculated a strong young man, and from the young man the Empress. Unless we realise the inconveniences, the uncertainties, the disasters and the horrors of the practice of variolation, albeit minimised, excused and denied by its professors, we can never understand the enthusiasm with which vaccination was received as its substitute. The promise conveyed in vaccination was a relief inexpressible, bearing with it a show of reason that was well nigh irresistible. The argument ran thus: No one can have smallpox twice, and the mildest attack is as protective from subsequent attack as the severest. Therefore it is that in inoculation with smallpox we find security. But inoculation with smallpox is an uncertain operation with dangerous issues. Here, however, in cowpox is discovered a mild variety of smallpox, which may be inoculated with perfect ease, and with no possibility of harm. And inasmuch as the mildest smallpox is as preventive of future smallpox as the severest, it follows that this gentle cowpox must serve as a full equivalent for smallpox itself. IMMEDIATE TRIUMPH OF VACCINATION. It was in this plausible shape that vaccination had an immediate triumph. The way was made straight for it and every difficulty removed by the existing practice of variolation. Dr. W. B. Carpenter says that vaccination was more strenuously resisted at the beginning of the century than it is at this day. He is completely mistaken. Vaccination came upon a generation prepared for it which saw in it a prescription in full accord with common-sense. The entire medical profession, with a few exceptions, the King, Queen and court, were converted straight off, and parliament and society followed suit. It was, I confess, a natural development of opinion; and we need have little doubt that had we lived in those days we should have found ourselves shouting with the genteel mob. The limited resistance offered to vaccination was not based on physiological or sanitary science: such science did not then exist. It was the resistance of variolators who were satisfied with the established practice and resented its disturbance; professing at the same time immeasurable horror at the pro fanation to humanity by infection with bovine disease. Whilst we have no reason to identify ourselves with that resistance, we have to recognise the service rendered by the variolators in observing the results of vaccinationthe persistency with which they traced and exposed its failure to prevent smallpox and the injuries and deaths it caused. So far as the maintenance of variolous inoculation was concerned, they fought a losing battle; but they drove the vaccinators from post to post (cursed while they did so as malignant false witnesses possessed of the devil) and at last compelled the admission that their infallible preventive could not be guaranteed to prevent, but only to make smallpox milder-a safe assertion because unverifiable, as disputable as indisputable in particular instances. JENNER'S PROCEDURE. About the matter of this prophylactic there was from the first a curious confusion which continues to this day. Jenner was a country doctor at Berkeley in Gloucestershire, a dairy country, where the maids believed that if they caught cowpox in milking they could never afterwards catch smallpox. Jenner when a young man was inclined to accept the dairymaids' faith; but when he discussed it with his medical acquaintance, they ridiculed him. They said, "We know that such is the dairy maids' "faith, but we also know that it is untrue; for we know "dairymaids who have had cowpox, and afterwards had "smallpox notwithstanding their cowpox." Jenner was convinced and said no more about cowpox. To this point let me draw special attention. No man knew better than Jenner that cowpox as cowpox was no preventive of smallpox. Toward middle-life he had what he conceived to be a happy thought. Cowpox as cowpox he had dismissed as impracticable; but there was a variety of cowpox which he resolved to recommend. Cows in Gloucestershire were milked by men as well as by women; and men would sometimes milk cows with |