"Who is that?" I said to my neighbor.
"Leverrier."
Delaunay was one of the most kindly and attractive men I ever met. We spent our evenings walking in the grounds of the observatory, discussing French science in all its aspects. His investigation of the moon's motion is one of the most extraordinary pieces of mathematical work ever turned out by a single person. It fills two quarto volumes, and the reader who attempts to go through any part of the calculations will wonder how one man could do the work in a lifetime. His habit was to commence early in the morning, and work with but little interruption until noon. He never worked in the evening, and generally retired at nine. I felt some qualms of conscience at the frequency with which I kept him up till nearly ten. I found it hopeless to expect that he would ever visit America, because he assured me that he did not dare to venture on the ocean. The only voyage he had ever made was across the Channel, to receive the gold medal of the Royal Astronomical Society for his work. Two of his relatives—his father and, I believe, his brother—had been drowned, and this fact gave him a horror of the water. He seemed to feel somewhat like the clients of the astrologists, who, having been told from what agencies they were to die, took every precaution to avoid them. I remember, as a boy, reading a history of astrology, in which a great many cases of this sort were described; the peculiarity being that the very measures which the victim took to avoid the decree of fate became the engines that executed it. The death of Delaunay was not exactly a case of this kind, yet it could not but bring it to mind. He was at Cherbourg in the autumn of 1872. As he was walking on the beach with a relative, a couple of boatmen invited them to take a sail. Through what inducement Delaunay was led to forget his fears will never be known. All we know is that he and his friend entered the boat, that it was struck by a sudden squall when at some distance from the land, and that the whole party were drowned.
There was no opposition to the reappointment of Leverrier to his old place. In fact, at the time of my visit, Delaunay said that President Thiers was on terms of intimate friendship with the former director, and he thought it not at all unlikely that the latter would succeed in being restored. He kept the position with general approval till his death in 1877.
The only occasion on which I met Leverrier was after the incident I have mentioned, in the Academy of Sciences. I had been told that he was incensed against me on account of an unfortunate remark I had made in speaking of his work which led to the discovery of Neptune. I had heard this in Germany as well as in France, yet the matter was so insignificant that I could hardly conceive of a man of philosophic mind taking any notice of it. I determined to meet him, as I had met Hansen, with entire unconsciousness of offense. So I called on him at the observatory, and was received with courtesy, but no particular warmth. I suggested to him that now, as he had nearly completed his work on the tables of the planets, the question of the moon's motion would be the next object worthy of his attention. He replied that it was too large a subject for him to take up.
To Leverrier belongs the credit of having been the real organizer of the Paris Observatory. His work there was not dissimilar to that of Airy at Greenwich; but he had a much more difficult task before him, and was less fitted to grapple with it. When founded by Louis XIV. the establishment was simply a place where astronomers of the Academy of Sciences could go to make their observations. There was no titular director, every man working on his own account and in his own way. Cassini, an Italian by birth, was the best known of the astronomers, and, in consequence, posterity has very generally supposed he was the director. That he failed to secure that honor was not from any want of astuteness. It is related that the monarch once visited the observatory to see a newly discovered comet through the telescope. He inquired in what direction the comet was going to move. This was a question it was impossible to answer at the moment, because both observations and computations would be necessary before the orbit could be worked out. But Cassini reflected that the king would not look at the comet again, and would very soon forget what was told him; so he described its future path in the heavens quite at random, with entire confidence that any deviation of the actual motion from his prediction would never be noted by his royal patron.
One of the results of this lack of organization has been that the Paris Observatory does not hold an historic rank correspondent to the magnificence of the establishment. The go-as-you-please system works no better in a national observatory than it would in a business institution. Up to the end of the last century, the observations made there were too irregular to be of any special importance. To remedy this state of things, Arago was appointed director early in the present century; but he was more eminent in experimental physics than in astronomy, and had no great astronomical problem to solve. The result was that while he did much to promote the reputation of the observatory in the direction of physical investigation, he did not organize any well-planned system of regular astronomical work.
When Leverrier succeeded Arago, in 1853, he had an extremely difficult problem before him. By a custom extending through two centuries, each astronomer was to a large extent the master of his own work. Leverrier undertook to change all this in a twinkling, and, if reports are true, without much regard to the feelings of the astronomers. Those who refused to fall into line either resigned or were driven away, and their places were filled with men willing to work under the direction of their chief. Yet his methods were not up to the times; and the work of the Paris Observatory, so far as observations of precision go, falls markedly behind that of Greenwich and Pulkova.
In recent times the institution has been marked by an energy and a progressiveness that go far to atone for its former deficiencies. The successors of Leverrier have known where to draw the line between routine, on the one side, and initiative on the part of the assistants, on the other. Probably no other observatory in the world has so many able and well-trained young men, who work partly on their own account, and partly in a regular routine. In the direction of physical astronomy the observatory is especially active, and it may be expected in the future to justify its historic reputation.