ing his whole bearing. After a few weeks he disappeared as he had come. "I must go," he said, "but I hope to be back soon." We were surprised to discover now that Demarcay had had his yellow spot removed—it was owing to Regnault's urgent representations—and, at the same time, we learned that the time granted for scientific journeys to every engineer of the School of Mines had expired in Regnault's case, but that Liebig, who had immediately discerned the eminent talents of the young man, had interceded in Regnault's behalf in Paris, in order that another sojourn at Giessen might be allowed to him. The request was granted, and Regnault came back.
Ten years later my destiny brought me to Paris. Agassiz, with whom I had worked five years at Neufchâtel, had emigrated to America, whither I did not want to accompany him. I was indebted to him for letters of introduction to some of the prominent members of the Academy of Sciences, which was then split into two great parties: one, headed by Arago, embraced the few republicans, the mathematicians and physicists; the other, led by the elder Brongniart, embraced most of the naturalists, the chemists, and the Orleanists. I had been recommended to the latter group; with Arago I was brought into closer contact by several radical Alsacians, whose acquaintance I had made partly during my flight from the gendarmes of his royal highness the Grand duke of Hesse, and partly afterward in Switzerland. I was to make my living in Paris by reporting the proceedings of the Academy of Sciences for the Augsburg Universal Gazette. Upon entering the gloomy hall for the first time, I immediately noticed Regnault; he sat with his dreamy gaze before a few papers, as before the retorts in the laboratory; and, after the lapse of ten years, looked as young and fresh as at Giessen. Thus I saw him for three years in Paris, and again after long intervals; and when, during the Franco-German War, he came to Geneva, broken-hearted because of the death of his excellent son, who, in his youth, had caused him many a pang by his mad freaks, but had afterward filled his heart with just pride and joy, the deep furrows of suffering, and the consequences of a dangerous fall several years before at the porcelain-factory of Sèvres, had been unable to obliterate his youthful appearance completely. But his last years were a long, slow agony; death had made the most cruel gaps in his family already, prior to the death of his son; the war had rudely destroyed the instruments which he had patiently collected for many years at Sèvres, and this destruction had affected him the more painfully, as the utmost precision and the most conscientious calculation formed the most essential peculiarity of his labors. Ever studious to detect the most insignificant sources of errors, to reduce miscalculations to their very minimum, to bring his apparatus and instruments to the highest degree of efficiency and technical perfection, Regnault will always be a shining model for those moving in similar paths of experimental physics.