“Would you have the strength to do it?  After a time you would become weary, for the burden would be too heavy, however great your devotion or profound your tenderness, to see my real position and my hopes, and, descending into the future, to see my ruin.  You know I am ambitious without having ever compassed the scope of this ambition, and of the hopes, dreams if you like, on which it rests.  Understand that these dreams are on the eve of being realized; two months more, and in December or January I pass the ‘concours’ for the central bureau, which will make me a physician of the hospitals, and at the same time the one for the admission, which opens the Faculty of Medicine to me.  Without pride, I believe myself in a position to succeed—­what sportsmen call ’in condition.’  And just when I have only a few days to wait, behold me ruined forever.”

“Why forever?”

“A man leaves his village for Paris to make a name for himself, and he returns only when bad luck or inability sends him back.  And then it is only every four years that there is a ‘concours’ for admission.  In four years what will be my moral and intellectual condition?  How should I support this exile of four years?  Imagine the effect that four years of isolation in the mountains will produce.  But this is not all.  Besides this ostensible end that I have pursued since I left my village, I have my special work that I can carry out only in Paris.  Without having overwhelmed you with the details of medicine, you know that it is about to undergo a revolution that will transform it.  Until now it has been taught officially, in pathology, that the human organism carries within itself the germ of a great many infectious diseases which develop spontaneously in certain conditions; for instance, that tuberculosis is the result of fatigue, privations, and physiological miseries.  Well, recently it has been admitted, that is to say, the revolutionists admit, a parasitical origin for these diseases, and in France and Germany there is an army looking for these parasites.  I am a soldier in this army, and to help me in these researches I established a laboratory in the dining-room.  It is to the parasites of tuberculosis and cancers that I devote myself, and for seven years, that is, since I was house-surgeon, my comrades have called me the cancer topic.  I have discovered the parasite of the tuberculosis, but I have not yet been able to free it from all its impurities by the process of culture.  I am still at it.  That is to say, I am very near it, and to-morrow, perhaps, or in a few days, I may make a discovery that will be a revolution, and cover its discoverer with glory.  The same with the cancer.  I have found its microbe.  But all is not done.  See what I must give up in leaving Paris.”

“Why give all this up?  Could you not continue your researches in Auvergne?”