The life of Pasteur

by René Vallery-Radot

In May, M. Roux gave a lecture on diphtheria at Lille, at the request of the Provident Society of the Friends of Science, which held its general meeting in that town. Pasteur, who was president of the Society, came to Lille to thank its inhabitants for the support they had afforded for forty years to the Society.

The master and his disciple were received in the Hall of the Industrial Society. Pasteur listened with an admiring emotion to his pupil, whose rigorous experimentation, together with the beauty of the object in view, filled him with enthusiasm. He who had said, “Exhaust every combination, until the mind can conceive no others possible,” was delighted to hear the methodical exposition of the manner in which this great problem had been attacked and solved.

At the Hygiene and Demography Congress at Buda-Pesth, M. Roux, repeating and enlarging his lecture, made a communication on the serotherapy of diphtheria which created a great sensation in Europe.

In France, prefects asked the Minister of the Interior how local physicians might obtain this antidiphtheritic serum. The Figaro newspaper opened a subscription towards preserving children from croup; it soon reached more than a million francs. The Pasteur Institute was now able to build stables, buy a hundred horses, render them immune, and constitute a permanent organization for serotherapy. In three months, 50,000 doses of serum were about to be given away.

Pasteur, who was then at Arbois, followed every detail with passionate interest. Sitting under the old quinces in his little garden, he read the lists of subscribers, names of little children, offering charitable gifts as they entered this life, and names of sorrowing parents, giving in the names of dear lost ones.

When he started again for Paris, October 4, 1894, Pasteur was seized again with the melancholy feeling which had attended his first departure from his home, when he was sixteen years old. He saw the same grey sky, the same fine rain and misty horizon, as he looked for the last time upon the distant hills and wide plains he loved, perhaps conscious that it was so. But he remained silent, as was his wont when troubled by his thoughts, his sadness only revealing itself to those who lovingly watched every movement of his countenance.

On October 6, the Pasteur Institute was invaded by a crowd of medical men; M. Martin gave a special lecture in compliance with the desire of many practitioners unaccustomed to laboratory work, who desired to understand the diagnosis of diphtheria and the mode in which the serum should be used. Pasteur, from his study window, was watching all this coming and going in his Institute. A twofold feeling was visible on his worn features: a sorrowing regret that his age now disarmed him for work, but also the satisfaction of feeling that his work was growing day by day, and that other investigators would, in a similar spirit, pursue the many researches which remained to be undertaken. About that time, M. Yersin, now a physician in the colonies, communicated to the Annals of the Pasteur Institute the discovery of the plague bacillus. He had been desired to go to China in order to study the nature of the scourge, its conditions of propagation, and the most efficient means of preventing it from attacking the French possessions. Pasteur had long recognized very great qualities in this pupil whose habits of silent labour were almost those of an ascete. M. Yersin started with a missionary’s zeal. When he reached Hong-Kong, three hundred Chinese had already succumbed, and the hospitals of the colony were full; he immediately recognized the symptoms of the bubonic plague, which had ravaged Europe on many occasions. He noticed that the epidemic raged principally in the slums occupied by Chinese of the poorer classes, and that in the infected quarters there were a great many rats which had died of the plague. Pasteur read with the greatest interest the following lines, so exactly in accordance with his own method of observation: “The peculiar aptitude to contract plague possessed by certain animals,” wrote M. Yersin, “enabled me to undertake an experimental study of the disease under very favourable circumstances; it was obvious that the first thing to do was to look for a microbe in the blood of the patients and in the bubonic pulp.” When M. Yersin inoculated rats, mice, or guinea-pigs with this pulp, the animals died, and he found several bacilli in the ganglions, spleen, and blood. After some attempts at cultures and inoculations, he concluded thus: “The plague is a contagious and inoculable disease. It seems likely that rats constitute its principal vehicle, but I have also ascertained that flies can contract the disease and die of it, and may therefore become agents for its transmission.”

At the very time when M. Yersin was discovering the specific bacillus of the plague in the bubonic pulp, Kitasato was making similar investigations. The foe now being recognized, hopes of vanquishing it might be entertained.

And whilst those good tidings were arriving, Pasteur was reading a new work by M. Metchnikoff, a Russian scientist, who had elected to come to France for the privilege of working by the side of Pasteur. M. Metchnikoff explained by the action of the white corpuscles of the blood, named “leucocytes,” the immunity or resistance, either natural or acquired, of the organism against a defined disease. These corpuscles may be considered as soldiers entrusted with the defence of the organism against foreign invasions. If microbes penetrate into the tissues, the defenders gather all their forces together and a free fight ensues. The organism resists or succumbs according to the power or inferiority of the white blood-cells. If the invading microbe is surrounded, eaten up, and ingested by the victorious white corpuscles (also named phagocytes), the latter find in their victory itself fresh reserve forces against a renewed invasion.

On November 1, in the midst of all this laborious activity and daily progress, Pasteur was about to pay his daily visit to his grandchildren, when he was seized by a violent attack of uræmia. He was laid on his bed, and remained nearly unconscious for four hours; the sweat of agony bathed his forehead and his whole body, and his eyes remained closed. The evening brought with it a ray of hope; he was able to speak, and asked not to be left alone. Immediate danger seemed avoided, but great anxiety continued to be felt.