“June 2, 1881.
“It is only Thursday, and I am already writing to you; it is because a great result is now acquired. A wire from Melun has just announced it. On Tuesday last, 31st May, we inoculated all the sheep, vaccinated and non-vaccinated, with very virulent splenic fever. It is not forty-eight hours ago. Well, the telegram tells me that, when we arrive at two o’clock this afternoon, all the non-vaccinated subjects will be dead; eighteen were already dead this morning, and the others dying. As to the vaccinated ones, they are all well; the telegram ends by the words ‘stunning success’; it is from the veterinary surgeon, M. Rossignol.
“It is too early yet for a final judgment; the vaccinated sheep might yet fall ill. But when I write to you on Sunday, if all goes well, it may be taken for granted that they will henceforth preserve their good health, and that the success will indeed have been startling. On Tuesday, we had a foretaste of the final results. On Saturday and Sunday, two sheep had been abstracted from the lot of twenty-five vaccinated sheep, and two from the lot of twenty-five non-vaccinated ones, and inoculated with a very virulent virus. Now, when on Tuesday all the visitors arrived, amongst whom were M. Tisserand, M. Patinot, the Prefect of Seine et Marne, M. Foucher de Careil, Senator, etc., we found the two unvaccinated sheep dead, and the two others in good health. I then said to one of the veterinary surgeons who were present, ‘Did I not read in a newspaper, signed by you, à propos of the virulent little organism of saliva, “There! one more microbe; when there are 100 we shall make a cross”?’ ‘It is true,’ he immediately answered, honestly. ‘But I am a converted and repentant sinner.’ ‘Well,’ I answered, ‘allow me to remind you of the words of the Gospel: Joy shall be in heaven over one sinner that repenteth, more than over ninety and nine just persons which need no repentance.’ Another veterinary surgeon who was present said, ‘I will bring you another, M. Colin.’ ‘You are mistaken,’ I replied. ‘M. Colin contradicts for the sake of contradicting, and does not believe because he will not believe. You would have to cure a case of neurosis, and you cannot do that!’ Joy reigns in the laboratory and in the house. Rejoice, my dear children.”
When Pasteur arrived, at two o’clock in the afternoon, at the farmyard of Pouilly le Fort, accompanied by his young collaborators, a murmur of applause arose, which soon became loud acclamation, bursting from all lips. Delegates from the Agricultural Society of Melun, from medical societies, veterinary societies, from the Central Council of Hygiene of Seine et Marne, journalists, small farmers who had been divided in their minds by laudatory or injurious newspaper articles—all were there. The carcases of twenty-two unvaccinated sheep were lying side by side; two others were breathing their last; the last survivors of the sacrificed lot showed all the characteristic symptoms of splenic fever. All the vaccinated sheep were in perfect health.
Bouley’s happy face reflected the feelings which were so characteristic of his attractive personality: enthusiasm for a great cause, devotion to a great man. M. Rossignol, in one of those loyal impulses which honour human nature, disowned with perfect sincerity his first hasty judgment; Bouley congratulated him. He himself, many years before, had allowed himself to judge too hastily, he said, of certain experiments of Davaine’s, of which the results then appeared impossible. After having witnessed these experiments, Bouley had thought it a duty to proclaim his error at the Académie de Médecine, and to render a public homage to Davaine. “That, I think,” he said, “is the line of conduct which should always be observed; we honour ourselves by acknowledging our mistakes and by rendering justice to neglected merit.”
No success had ever been greater than Pasteur’s. The veterinary surgeons, until then the most incredulous, now convinced, desired to become the apostles of his doctrine. M. Biot spoke of nothing less than of being himself vaccinated and afterwards inoculated with the most active virus. Colin’s absence was much regretted. Pasteur was not yet satisfied. “We must wait until the 5th of June,” he said, “for the experiment to be complete, and the proof decisive.”
M. Rossignol and M. Biot proceeded on the spot to the necropsy of two of the dead sheep. An abundance of bacteridia was very clearly seen in the blood through the microscope.
Pasteur was accompanied back to the station by an enthusiastic crowd, saluting him—with a luxury of epithets contrasting with former ironies—as the immortal author of the magnificent discovery of splenic fever vaccination, and it was decided that the farm of Pouilly le Fort would henceforth bear the name of Clos Pasteur.
The one remaining unvaccinated sheep died that same night. Amongst the vaccinated lot one ewe alone caused some anxiety. She was pregnant, and died on the 4th of June, but from an accident due to her condition, and not from the consequences of the inoculation, as was proved by a post-mortem examination.
Amongst the cattle, those which had been vaccinated showed no sign whatever of any disturbance; the others presented enormous œdemata.