protect, leaving the person still susceptible to a more or less severe attack of varioloid small-pox.

I think we should gain something in precision, in exact conformity of language to scientific fact, if we were to discard the words vaccination, cow-pox, vaccinia, varioloid, etc., and use the terms natural small-pox, inoculated small-pox, and vaccine small-pox. a misleading nomenclature causes people to imagine that vaccination is an attempt to prevent one disease by another, against which the instinct of reason occasionally rebels, notwithstanding an overwhelming array of facts in its favor.

PUBLIC PROTECTION BY MEANS OF VACCINATION, OR, MORE PROPERLY SPEAKING, BY INOCULATION OF VACCINE SMALL-POX.

In comparison with the long ages of man's life on this planet, non-infectious vaccine small-pox, or vaccination, is a new thing. Sixteen years less than a century ago Jenner published his discovery to the world. Only eighty-four years have elapsed, yet the most dreaded of diseases to which man is subject has already lost the greater part of its terrors. Against the inertia of indolence and apathy, against ignorance and superstition, against dulness and prejudice, against heavy who were treating cases of the disease. He succeeded thirty-three times. His experiments were watched by many medical men. Mr. Marson, a very eminent authority in vaccination, used Badcock's lymph for many years. Sir Thomas Watson, in his famous medical treatise, bears testimony to Badcock's success. John Simon, writing officially in 1857, three years before the close of the experiments, says that more than fourteen thousand persons have been vaccinated with such lymph, and more than four hundred medical practitioners have been furnished with supplies of it. A detailed account of the matter may be found in an address of Mr. Hodson, delivered before the British Medical Association, at Ryde, in August, 1881, published November 26, 1881, in the British Medical Journal.

Per contra, Dr. Klein, under the supervision of Dr. Burdon-Sanderson, experimented on thirty-one cows, with negative results. (See ninth annual report of the Local Government Board of England, for 1879, 1880). The Lyons Commission, of which Chauveau was a member, made extensive experiments in 1865, without affirmative results. An Italian commission was equally unsuccessful. The Belgian commission of 1881, including Dr. Warlomont, also failed. Veterinarysurgeon Fleming, of the British war office, has written a pamphlet entitled Human and Animal Variola, in which he maintains that cowpox and small-pox are essentially different diseases.

It is evident, again, that a single uncontested success in conveying human variola to the cow by inoculation, and returning it to man by the same process as genuine non-infectious vaccine pox, establishes an affirmative answer to the question under discussion. Any number of failures in attempted experiments of the kind prove nothing more than the difficulty of performing the operation.

(2) Accounts of communicating human variola to cows by infection, belong to a realm too shadowy for science.

(3) We have no facts that enable us even to conjecture whether successful inoculation of the cow with small-pox needs the aid of infection.

conservatism and unreasoning tradition, the practice of vaccination has spread in a few decades over the whole civilized world, to the vast benefit of mankind.

A few salient facts and groups of facts will demonstrate to any rational human being the immeasurable utility of vaccination, or, in other words, of inducing, by inoculation, noninfectious vaccine small-pox.

(1) The great mass of people in all enlightened nations have come to believe in it, from observation and experience. Vox populi, vox Dei. Enlightened public opinion is a very good, although not infallible, criterion of truth.

(2) Educated medical men are almost unanimous in favor of vaccination. Simon addeessed a question, "purposely construed to elicit the expression of every existing doubt on the protective influence of vaccination," to five hundred and fortytwo distinguished medical men, British and foreign, and received an affirmative answer from all but two of them. The Britishepidemiological Society published a report of its small-pox and vaccination committee, in 1853, wherein reference is made to favorable answers from more than two thousand British medical men, besides many in other countries. In America to-day,

(4) Neither have any experiments been made to determine whether successful inoculation requires the concurrence of epidemic influence.

(5) Whether infection and epidemic influence combined can convey small-pox to the cow, is unknown.

(6) Whether inoculation, infection and epidemic influence must concur, in order to convey human variola to the bovine animal, although opening a fruitful field of tentative hypothesis, is a question on which not even a single observation, scientifically made, has cast a ray of light.

The argument from the analogy of known facts, in favor of the essential identity of small-pox and cow-pox, is very strong. It is enough to say that no zymotic disease exhausts susceptibility to another. The vaccine of M. Pasteur for chicken cholera is experimentally based on the identity of the vaccine and the disease of which it is prophylactic.

The argument relied on in favor of the essential difference of vaccinia and variola is from their clinical history. The experiment of Thiele, first published in Henke's Zeitschrift, in 1839, not only renders this argument baseless, but strongly corroborates the argument from analogy of the identity of these diseases. "Take some smallpox lymph," says Thiele, "and keep it between waxed glasses for ten days; then moisten and dilute it with cow's milk, and with this inoculate a child. The lymph from this child is again to be kept between waxed glasses for ten days, then diluted with milk, and transferred to another child, and so on-the same process being repeated to a tenth child. By this time the disease will have become as benign and noninfectious as cow-pox, the successive ten children having manifested it in a gradually milder form, the secondary fever and secondary pustules around the inoculated part having gradually ceased to occur; and thenceforth the lymph may be propagated directly from child to child (without keeping or milk dilution) just as in ordinary vaccination."

as well as in other countries, the physicians who do not favor vaccination are exceptions to the general rule.

(3) The governments of nearly all civilized nations favor vaccination, and some of them make it compulsory. The British and German governments, both of them conservative and enlightened, require it. The legislature of nearly every state in this Union has enacted a law favoring it.

Statistics on a large scale demonstrate the utility of vaccination. In Moravia, Bohemia and Austrian Silesia, vaccination reduced the annual mortality of four thousand in every million of population, by small-pox, to two hundred. In Westphalia, where the death rate from small-pox was formerly two thousand six-hundred and forty-three in the million of population, the annual mortality from the same cause declined to an average of one hundred and fourteen in the million from 1816 to 1850, under the influence of general vaccination. From 1810 to 1850 the yearly death rate from small-pox in Sweden was one hundred and fifty-eight per million of population, but was two thousand and fifty before vaccination. In Berlin the reduction was from three thousand four hundred and twenty-two to one hundred and seventy-six; in Copenhagan, from four thousand to two hundred. At the close of the last century the esti

The doctrine of the duality of vaccinia and variola, involves one of two things: either vaccinia arises from time to time de novo in the cow, or it has a continued existence in the bovine race. Whoever maintains the former must maintain not only the spontaneous origin of species, but also the repeated spontaneous origin of the same species at intervals. Whoever maintains the latter, must maintain a zoölogical history of unbroken continuousness of vaccinia, or animal variola, in the cow.

There are certain local histories, based on the observation of the common people, attested by the belief of the common people, which throw some light, although not scientifically certain light, on the question of the possibility of conveying small-pox from man to the bovine species. In the midst of the current facts of such a local history in Gloucester, England, Jenner made his great discovery. M. Negri, the originator of propagating bovine virus, three times obtained a fresh supply from cows in Calabria. At Beaugency, in the department of Loiret, France, a fresh "stock" was obtained from an infected herd. A fresh supply was also obtained at Saint Mandé, near Paris. In 1865, a new "stock" was secured at Esneaux, in the province of Liege, Belgium, which is now propagated under the direction of Dr. Warlomont, at Brussels.

It is certain that when milkers, having small-pox, convey the disease to cows, the animals are subjected to the combined influence of epidemic influence, infection and inoculation. In my judgment, future experimenters would do well to keep in view all of these conditions. If the Federal Government shall undertake the duty of supplying the whole country with vaccine virus, here is presented to the National Board of Health a useful field for exhaustive investigation.

Finally, however interesting this discussion may be from a scientific point of view, the practical value of vaccination does not at all depend upon the solution of the question, whether vaccinia and variola aro two distinct diseases or modifications of the same disease.

H

mated rate in England was three thousand. The average rate of 1841-1853 was three hundred and four. The average rate of 1854-1863, embracing two severe epidemics, was one hundred and seventy-one per million of population. Yet there are men, apparently rational, who denounce vaccination, without suspecting that they are making themselves public malefactors.

(5) Special statistics demonstrate the benefits of vaccination not less strikingly than general statistics. Dr. Seaton and Dr. Buchanan, both of them skilled observers, examined, in various London schools and workhouses, during the epidemic of small-pox in 1863, over fifty thousand children. A large majority of them had been vaccinated in various ways and degrees. Three hundred and sixty out of every thousand who had not been vaccinated were scarred with small-pox. Less than two in one thousand of those who showed evidence of vaccination had small-pox marks. Only one in over one thousand six hundred who had perfect vaccine marks showed pitting from small-pox. Mr. Marson observed and carefully recorded thirty-thousand cases of small-pox under his personal care in the London Small-pox Hospital. Deaths among the unvaccinated were thirty-seven per cent.; among the vaccinated, six and one-half per cent.

The general drift of statistics on the subject, collected during the current century, is in the same direction. I have no doubt that the present epidemic of small-pox in the United States would be quite as calamitous as the great war of the rebellion, without the protection afforded by vaccination. Were the protection as perfect as it might have been, we should scarcely know of the existence of small-pox.

DEGREES OF PROTECTION BY VACCINATION.

Efficient vaccination, that is, vaccination with pure virus and properly performed is, in my judgment, just as complete protection against small-pox as an attack of the disease in the natural way. "Duly and efficiently performed," said Jenner, "it will protect the constitution from subsequent attacks of small-pox as much as the disease itself will. I never expected it would do more; and it will not, I believe, do less." Nature does her work perfectly. The element of art enters into vaccination, and the degree of its success depends upon the material used and the skill of the operator. The best vaccinator cannot produce good results with imperfect matter. The best virus. may fail in the hands of a bungler. If such grand results in favor of vaccination, as already presented, are attained by work that is imperfect, what might we not expect with the science, skill and pains which are surely within human reach? Failure of vaccination may involve consequences more dangerous to the individual than the amputation of an arm. Yet we seek a careful and skilled surgeon to perform the latter operation,

while any blunderhead is supposed to be capable of performing the former. The surgeon is contented with only the best instruments and dressings when he undertakes a capital amputation. Yet, when he undertakes to protect a fellow-being against a disease, which, taken in its natural form, kills four out of ten of all who have it, he sometimes uses any kind of a knife, and exercises less care in the selection of virus than he would in the choice of a sleeve button. As pointed out in one of the reports of the medical officer of the British Privy Council, the degree of protection afforded by vaccination varies as one to thirty. And the worst of it is, that sloven vaccination, with imperfect or worthless virus, brings the great and beneficent discovery of Jenner into disrepute.

SOURCES OF VACCINE VIRUS.

In order to make clear a subsequent and essential part of this discussion, it is worth while to devote here a few words in explaining how we obtain supplies of vaccine matter. Until quite recently most of the virus used was obtained from the vaccine sore on the human arm. Lymph from a vaccine vesicle seven days old, from the "pearl on the rose," as it was termed, alluding to the red base of the vesicle, was regarded as the perfection of virus. Arm to arm vaccination was considered as the faultless method.. Thus from one person to another the supply was kept up. Now, the fashion is to use calves or heifers for the perpetuation of the needed supply. It is supposed by many that calves or heifers are all inoculated with small-pox in order to procure a supply of vaccine virus. The animals are simply vaccinated. It would be rather a serious business to keep a steady supply of small-pox on hand, in order to run a vaccine stable, to say nothing of the extreme difficulty of the operation. The difference between bovine virus and humanized virus is that the former is perpetuated from calf to calf, and the latter from man to man. Both are good. The bovine matter is preferred, for the simple reason that with humanized matter certain dreaded diseases may be inoculated with vaccination. Besides, the production of bovine virus can be carried on in a much more regular way, affording a constant, unlimited supply, as needed. I have no doubt that the danger of inoculating diseases with humanized lymph is greatly exaggerated, but the public is entitled to the benefit of a doubt, in favor of the bovine. A much greater source of danger is in vaccinating with unclean knives. The blood of a syphilitic person may be left on the point of a lancet and pricked into the arm of an innocent person. The blade used by the operator should be held in flame after each vaccination.

VACCINATION, THEREFORE, IS THE CHIEF MEANS OF COMBATTING NATURAL SMALL-POX.

The problem, how to combat small-pox, resolves itself, in great part, into the practical problem how to get the people