This was but the beginning of the war; soon it spread with vertiginous rapidity, and made its cruel destructive force felt.

On our return from Norka, we found everything on a war footing. The very next morning, Metchnikoff hurried to the laboratory. He only reached Paris with some difficulty, all means of communication being encumbered by soldiers. He had left the house nervous and excited but full of courage and energy. I shall never forget his return home....

I was awaiting him as usual, just outside the station, and, as he got out of the train, I did not recognise him. I saw a stooping old man, bent as under a heavy burden; his usual vivacity was gone, and had given place to the deepest depression.

He told me in a broken voice that the Institute was already deserted; that it was under the orders of the military authorities, and completely disorganised for scientific work. The younger men were mobilised; the laboratories empty; the animals used for experiments had been killed on account of the departure of the servants, and for fear of a lack of food. Everything that had been devoted to the service of science and of research into means of preserving life had been handed over to the service of war. Normal and cultured life was arrested. And that was the outcome of civilisation.

Metchnikoff felt as if he had suddenly been dropped into the abyss of centuries, into the times of human savagery. He could not accustom his mind to the idea of such a fall; it seemed to him a paradox, an impossibility, that civilised peoples could not do without sanguinary fights in order to solve questions of mutual relations.

The events which were taking place agitated and depressed him all the more that he had not the possibility of becoming absorbed in scientific investigations; he was completely thrown off his balance.

And as, one by one, the news came of the death in action of several of the young men who had left the Institute, Metchnikoff’s grief knew no limits. He could not bear the idea, now a terrible reality, that these brilliant young lives should be sacrificed, victims of those who should have directed the peoples towards peace and a rational life, and who, instead of that, threw the most precious part of humanity into the abyss of death. War became a dark, sinister background to his daily life. The victims of war were not only those who fell on the battle-field, but included him whose whole life-effort had been directed towards the conservation of human existence and the search for rational conceptions. The contrast between his aspirations and the cruel reality had been to him a blow which his sensitive and suffering heart was not fit to bear.

The Germans were advancing rapidly. Then came the sad days of panic, when the inhabitants were leaving Paris in numbers and the Government started for Bordeaux. At night, the sky was swept by the gigantic, luminous sword of the searchlights; the rumble of cannon could be heard in the distance....

Metchnikoff, however, had no personal fear whatever. He very simply decided on his course of action, which was to remain at the Institute if his presence there could be of use; if not, to retire to some quiet place where he could work. As there was hardly any staff left at the Institute on account of the mobilisation, he did not go away, but, on the contrary, we came to live in Paris, the communication with SÈvres being very difficult.

The day we arrived was that on which the first German aeroplanes appeared, and they dropped bombs near the St. Lazare station just as we were alighting from the train. For some time after that, they carried out a raid above Paris every Sunday.

In spite of the disorganisation of his whole life, Metchnikoff had succeeded in resuming his work to a certain extent. He took advantage of an opportunity to observe an old dog who was suffering from diabetes, and hastened to examine his organs as soon as he died, whilst they were still fresh. He had for some time supposed that diabetes might be an infectious disease; yet he was unable to discover any specific microbe either in the humors or in the organs of the dog. But he succeeded in provoking symptoms of the disease (traces of sugar in the urine) in a healthy dog, by inoculating him with the pancreatic gland of the diabetic dog. He was much encouraged by this result, and would have liked to continue his researches, but was unable to do so because of the general disorganisation and the impossibility of obtaining animals for experiments. He had to content himself with continuing his memoir on infantile cholera and his observations on the silk-worm moth.

As he was almost altogether precluded from laboratory work, he began to write a study on “The Founders of Modern Medicine,” in order to demonstrate, by concrete examples, the importance of positive science in its application to life. This is what he said in his preface to the book:

After describing the state of medical science before Pasteur, Lister, and Koch, Metchnikoff compared with it modern medicine, created by these three Founders, and showed the great horizons opened by them to the medicine of the future.

On the 26th of September 1914, whilst we were still in Paris, he had, in the laboratory, an attack of tachycardia, which lasted three hours but was much less violent than that of the year before. The winter, however, passed fairly well in spite of the emotions and continuous excitement caused by the war, and he had no other attack until April 1915, when again he had a slight tachycardiac crisis of a short duration. Yet he was very much changed: his hair was much whiter, his movements were slow, and his figure bent. His infectious gaiety and vivacity had disappeared, but he remained energetic and enthusiastic in his work, and gained more and more in serenity.

Little children in the street called him “Father Christmas,” and came confidingly to ask him for presents. They knew him well, and were aware that his pockets were always filled with sweets for them. He used to say that his growing love for children was the revelation of the grandfatherly instinct, for which he had reached the proper age. He especially loved one of his god-daughters, little Lili; he had become attached to the child on account of her kind heart and exceptional sweetness, and also because, from the cradle, she had shown a marked preference for him. And yet his love for children was not to him a source of joy, for anxiety on their account predominated over other feelings.

In spite of the physical change which had supervened, his brain continued to work untiringly as in the past, and he tackled new problems with youthful courage and boldness. He had planned a work on the sexual question, which, according to him, was treated erroneously, with the result that grave disharmonies occurred in human existence.

Thus he reached some quite revolutionary conclusions respecting education and marriage. He thought that morality should be set upon a quite different basis, new and rational; and that was the question which he prepared to treat.

The 16th of May of that year was his seventieth anniversary.

His satisfaction was great at having reached the normal limit of age, for he saw in that a conclusive proof of the efficacy of his hygiene. Indeed, he showed on that day a sort of rejuvenation: his aspect was quite different, he was gay and animated as he had not been for a long time.

The Pasteur Institute celebrated his jubilee. In spite of the absence from “The House” of many members on account of the war, the library filled with people, and the fÊte had a cordial and intimate character. Dr. Roux’s speech[31] will remain the best description of E. Metchnikoff and of his scientific activity. He himself responded to all those manifestations of sympathy by a spirited speech, in which, À propos of his own particular case, he expounded his ideas on senility and the duration of life in general. This is what he wrote on that same day in his note-book:

We spent that summer a few weeks at Norka, where Metchnikoff completed his researches concerning the death of the silk-worm moth.

We went for delicious walks; we spent all the afternoon by the lake or under the pines in the heather, reading and working. Once only, during a walk, he had a strong cardiac intermittence, but as a rule he felt well. I could see, however, that he was obsessed by a grave preoccupation which he did not express. Later, during his last illness, he confessed to me that during the whole of that stay at St. LÉger he had feared to die suddenly during one of our walks. The thought of my isolation weighed on his mind and he hid his anxiety so as not to alarm me....

With a view to the work which he had planned on the sexual question, he interested himself in the influence that their sentimental life had had on the activity of great men, and we read together the biographies of Beethoven, Mozart, and Wagner. Elie was more than ever desirous of making our holidays as pleasant as possible, as if he already felt that they were our last. Here are more extracts from his note-book:

He spent the autumn collecting and preparing the materials he required for his book on the sexual function. It was a relief from the sad impressions of the war and the deserted laboratory. But new troubles were in store for us; I became ill, and had scarcely recovered when we heard the news of the death of a nephew who was very dear to us. The death of the young had always deeply moved Metchnikoff, and it was so in this case. It was another weight thrown into the already descending scale.

In spite of all, he continued to work with enthusiasm, planting young trees that future generations might enjoy their shade.