Eclipses of the Sun are very rare for a definite spot. Thus not one occurred for Paris during the whole of the nineteenth century, the last which happened exactly above the capital of France having been on May 22, 1724. I have calculated all those for the twentieth century, and find that two will take place close to Paris, on April 17, 1912, at eighteen minutes past noon (total for Choisy-le-Roi, Longjumeau, and Dourdan, but very brief: seven seconds), and August 11, 1999, at 10.28 A.M. (total for Beauvais, Compiègne, Amiens, St. Quentin, fairly long: two minutes, seventeen seconds). Paris itself will not be favored before August 12, 2026. In order to witness the phenomenon, one must go and look for it. This the author did on May 28, 1900, in Spain. The progress of the lunar shadow upon the surface of the Earth is traced beforehand on maps that serve to show the favored countries for which our satellite will dispense her ephemeral night. The above figure shows the trajectory of the total phase of the 1900 eclipse in Portugal, Spain, Algeria, and Tunis. [Illustration: FIG. 77.--The path of the Eclipse of May 28, 1900.] The immutable splendor of the celestial motions had never struck the author so impressively as during the observation of this grandiose phenomenon. With the absolute precision of astronomical calculations, our satellite, gravitating round the Earth, arrived upon the theoretical line drawn from the orb of day to our planet, and interposed itself gradually, slowly, and exactly, in front of it. The eclipse was total, and occurred at the moment predicted by calculation. Then the obscure globe of the Moon pursued its regular course, discovered the radiant orb behind, and gradually and slowly completed its transit in front of him. Here, to all observers, was a double philosophical lesson, a twofold impression: that of the greatness, the omnipotence of the inexorable forces that govern the universe, and that of the inexorable valor of man, of this thinking atom straying upon another atom, who by the travail of his feeble intelligence has arrived at the knowledge of the laws by which he, like the rest of the world, is borne away through space, through time, and through eternity. The line of centrality passed through Elche, a picturesque city of 30,000 inhabitants, not far from Alicante, and we had chosen this for our station on account of the probability of fine weather.