that of anthrax. Having discovered the bacillus, these gentlemen, by actual experiment, demonstrated the fact that it was possible to protect animals against black-quarter by inoculation with an attenuated virus. This method of preventive inoculation has proved successful in France and Switzerland, as the following data will show. In France 5,835 head of cattle have been inoculated against blackquarter. The mean mortality from the disease in the districts where this mode of vaccination is now used was not less than 10.84 per cent., and not unfrequently reached 17 per cent. After preventive inoculations had been introduced, and although they were not applied all over the country, the mortality at once fell to 2.15 per cent. per annum.

During the year 1884, 2,199 animals were inoculated against black-quarter in Switzerland. Of these 22 per cent. died from the disease during the year, whereas of the non-vaccinated cattle 6.1 per cent. died. In other words, the mortality amongst the non-inoculated was twenty-eight times as large as amongst the inoculated cattle.

In 1887 the agricultural societies of the Jura performed an experiment on a very large scale. They caused 1,703 head of cattle to be inoculated against black-quarter, and then turned them out to graze in various parts of the country with 18,720 head of cattle which had undergone no treatment.

The summer over, the mortality from this disease amongst the non-inoculated animals proved to be 1.33 per cent., whereas amongst those that had undergone the preventive treatment the death-rate amounted to 1.75 per thousand only. Since 1885, inoculations against black-quarter have been performed on a large scale in the Canton Berne, as, in order to obtain compensation for losses caused by infectious disease, farmers must bring proof positive that every means has been tried which is known to prevent the occurrence of the diseases, and amongst these means the authorities very properly include preventive inoculations. In 1883 and 1884 respectively, when this method had not yet been introduced, 522 and 712 animals died from black-quarter, but as soon as inoculations were properly carried out the mortality fell to seventy per annum.

Similar facts have been observed in the Canton of Freiburg. Previous to the year 1884, 140 to 150 head of cattle perished annually from the disease. In that year the method of preventive inoculations was first tried, and the number of deaths from blackquarter fell to 136 in 1884, to 119 in 1885, 107 in 1887, 69 in 1888, and 45 in 1889.

During the last five years, out of 36,744 head of cattle, in the same canton, 14,444 were inoculated against black-quarter, and of these one in 555 died from the disease. On the other hand, 22,300 animals were not inoculated, and of these one in forty-three perished. It occasionally happens that an animal dies from the inoculation, Arloing, Les Virus.

6

just as sickly children sometimes perish after vaccination. The owners of the animals are then duly indemnified; but, in spite of such losses, the cost of preventive inoculations only amounts to fourpence-halfpenny per head.

Mr. Herbert Spencer states in one of his works that, excluding these inductions that have been so fully verified as to rank with exact science, there are no indications so trustworthy as those which have undergone the mercantile test.' During the last ten years the method of preventive inoculations has indeed undergone the mercantile test. The methods which were looked upon with something like distrust by the highest scientific authorities now stand on the firmest possible basis, and their practical value is acknowledged even by those who at first bitterly opposed their application. Agriculturists-who cannot be accused of belonging to a scientific clique, who know nothing and care less about theoretical considerations or bacteriology-are clamouring for the vaccines.

Interesting as are these results, they are perhaps of less importance than what has been accomplished in the prevention of another disease, which affects both man and animals-namely, rabies or hydrophobia.

7

I have in another paper given full details as to how Pasteur was led to make his remarkable discovery, and I must refer the reader to my former publication on this subject. I will now come at once to the results obtained in man by Pasteur's treatment.

A few details are here necessary, for we have to consider what the mortality amounted to in human beings who were bitten by rabid dogs before the invention of Pasteur's treatment. I have collected most of the statistics on this subject, and I find the mortality of persons bitten on any part of the body varied between 15 and 50 per cent.; but, for the sake of argument, I will assume 15 per cent. to be the correct figure--although I believe this number to be far too low. The tables on next page show the results obtained by Pasteur's treatment in Paris."

If we take into consideration only the cases contained in Column A-that is, cases in which there cannot be the shadow of a doubt that the animals which bit the patients were rabid-we see that the total mortality, including the cases dying before the treatment could have any effect, including the cases which came to the Institute after their fellows bitten at the same time had died of rabies, we see that this total mortality is a little over one per cent.

"British Medical Journal, Sept. 21, 1889.

It is noteworthy that, although M. Pasteur employs rabbits for the production of virus of rabies, the fact that dogs are not used at the Pasteur Institute for that purpose, although repeatedly pointed out, has been persistently ignored by the antivivisectionist party, who in their letters to the papers talk of the thousands of dogs' inoculated by M. Pasteur.

• Perdrix, Annales de l'Institut Pasteur. 1890.

Column A refers to patients bitten by animals which were undoubtedly rabid, the proof being that an animal bitten at the same time died of rabies, or that a piece of the spinal cord of the animal which inflicted the bite inoculated into a rabbit produced rabies in this animal.

Column B refers to patients bitten by animals certified to be rabid by veterinary surgeons.

Column C refers to patients bitten by animals suspected of being rabid, but which were not actually proved to be so. I have, from repeated inquiries, no hesitation in stating that most of the persons in Column C were bitten by animals really rabid.

Before M. Pasteur's treatment was applied, the mortality among people bitten in the face by rabid animals amounted to 80 per cent. I find that in the years extending from 1885 to 1889, 593 persons bitten in the face were inoculated at the Institut Pasteur in Paris. The total mortality is 2·23 per cent.

In the year 1887, 350 persons were bitten in Paris by rabid animals. 506 were inoculated by M. Pasteur and three died (mortality 97 per cent.); forty-four declined to be inoculated, and seven of these are known to have died of rabies (mortality 15.9 per cent.). These facts were elucidated by careful inquiries made by an independent medical man acting for the Prefect of Police.

Since the foundation of the Pasteur Institute in Paris similar Institutes have been established all over the world, and I have before me, at the time of writing, the reports of such institutes in Russia, Hungary, Italy, Sicily, Brazil, Turkey, the United States, Roumania, and other countries. In all Pasteur's results have been confirmed, and in a large number of them the method has proved even more successful than in Pasteur's hands. I have also in my possession notes of a number of cases in which some were submitted to the treatment, whilst others bitten by the same rabid animals declined. to be inoculated. The result was that the inoculated persons recovered, whilst those who for some reason or other refused to be treated died of hydrophobia. It is my firm conviction that of all the treatments which have ever been invented for the prevention of an infectious disease, not one (vaccinia perhaps excepted) has proved so successful as Pasteur's treatment against rabies.

In a lecture on rabies and its preventive treatment, which I had the honour of delivering before the Society of Arts on the 5th of December, 1889, I attempted to answer the following question: Suppose you had been bitten by a dog, and the veterinary surgeon had told you that the animal was rabid, or suppose you had been bitten by a stray dog which you believed to be rabid, what would you do?' After enumerating the evidence I possessed at the time, I answered: 'If ever I am bitten by a rabid dog, or one which I believe to be rabid, I shall take the first train to Paris and be inoculated.' Since that time I have, every month, carefully scrutinised the statistics of the Institut Pasteur, and on the occasion of the last 'International Congress of Hygiene,' I asked for details from some of the directors of the antirabic institutes of Russia, Roumania, Italy, and America, many of whom fully answered my queries. What I said on the 5th of December, 1889, I now repeat with renewed emphasis.

If I am compelled to lay so much stress on the value of Pasteur's treatment, it is because some people, whose object is to show that no good can possibly come out of experiments on animals, still go on advocating other methods of treatment. Again I repeat it, there is no treatment which will prevent the occurrence of rabies in a person bitten by a rabid animal, except Pasteur's method of preventive inoculation. When a human being is bitten by a rabid animal, every moment lost in applying a useless treatment increases the danger, every moment lost may prove a fatal delay. Does it not show a devilish disregard of human life' to extol modes of treatment which have been proved to be useless by every man who has studied the question ? 10

Had space allowed, this would have been a fitting opportunity of giving an account of the results obtained against other infectious diseases, such as swine fever. The researches on the chemical substances secreted by micro-organisms might also have interested the reader, but the question is too wide to be more than mentioned here. Already, however, there are indications to show that in a short time

10 It is not my intention to take Pasteur's defence against the calumnies which have been heaped upon him by his unscrupulous opponents. Pasteur requires no defence, for his works stamp him as one of the greatest benefactors of humanity. I may, however, give one specimen of the style of attacks made against him. In an anti-vivisectionist paper, M. Pasteur is accused of having invented the preventive treatment of rabies in order to benefit the Paris hotel keepers. I think it would be difficult to match this piece of slanderous imbecility, even at a political meeting. Had M. Pasteur tried to carry out his researches in this country, he would have had the greatest difficulties in obtaining permission to do so. Suppose he had triumphed over his difficulties, then, after spending his life in trying to advance knowledge and saving human and animal lives, a respectable paper' would no doubt publish a letter stating that a man who performs experiments on animals is farther down the pit' than a drunkard, a debauchee, a liar, or a thief' (Manchester Guardian, October 6, 1891). And this from a lady who boasts that the heart of Christian England' is on her side (Star, August 1891).

bacteriologists will have discovered ways of curing diphtheria with methods based on strictly scientific principles.

In the preceding lines, it has been proved that bacteriology is the direct outcome, not of one branch of knowledge only, but of all the divisions of natural science, biology, chemistry, and others. But during its growth even, it shed the greatest light on the sciences of which it is an offshoot. The first step in bacteriology was made through chemical investigations; but, on the other hand, see what the new science has done for chemistry. It has solved for chemists some of the chief problems connected with putrefaction and fermentation, problems which were previously in a state of hopeless obscurity. Through bacteriology, chemists have learnt that each kind of specific fermentation is due to a specific micro-organism, which placed under definite conditions produces definite chemical substances, and in this manner bacteriologists have discovered substances the existence of which chemists did not even suspect.

Have not bacteriologists also revolutionised botanical methods by new modes of cultivating micro-organisms; by showing that every colony of microbes has its own particular aspect; by improved methods of staining, so that previously invisible bacteria are now easily seen; by inventing photographic processes of such delicacy that structures invisible to the naked eye are now readily perceived in the plate; and by enriching the flora with countless new genera previously unknown?

The men to whose genius we owe the 'new science' were merely seeking for truth and had no practical object in view, but gradually gained this useful knowledge through experiment-physical, chemical, and physiological. Hundreds of human lives, snatched from death through Pasteur's treatment; thousands of human beings restored to health every year through perfected systems of medicine and surgery; millions of animals protected against infectious disease, have been saved through the knowledge gained by experiments on animals. Those who expect that the science of medicine will make any startling progress without having recourse to experiments on animals, might just as well expect to see brilliant discoveries in chemistry without new and improved methods of chemical experimentation.

Suppose a man who had never seen a steam engine at work was told to set it going. If an acute observer, he might, by taking that engine to pieces, form a very shrewd guess as to the use of its various parts, of its boiler, its stop-cocks, and its furnace; but how could he be sure that his suppositions were correct until he had actually seen the engine at work-in other words, until he had performed an experiment? Suppose he had surmounted this primary difficulty, would he be able to work his engine without