THE DISCOVERY OF THE PLANET VULCAN.
Leverrier, encouraged and made illustrious by his success in exploring those infinite spaces beyond the orbit of Herschel, turned his attention to the innermost circles—the central region of our solar system. By theoretical demonstrations, based on irregularities in the movements of Mercury, he proved the existence of some planet or planets lying still more closely within the light and heat of the sun. While proceeding with his calculations, he received a letter from Lescarbault—a poor physician of Orgères, a village in the department of Eure and Loire, in France—announcing the discovery of an intra-Mercurial body, making its transit, in appearance like a small black spot, across the disk of the sun. Possessed of a sensitive and modest soul,—as all true lovers of science are,—the doctor at first doubted the reality of his discovery, and hesitated to make it known. It was only after vainly waiting nine months, to verify his observation by another view of the object, that he prepared a letter, narrating what he thought he had seen, and sent it to the great Leverrier. The latter had just published an article on Mercury’s perturbations in the Kosmos of Paris. Astonished at this coincident proof of the correctness of his theory, he lost no time in starting for the village of Orgères, to obtain a personal interview with the humble discoverer of the new orb. The following account of the meeting was reported in the Kosmos by the Abbé Moigne, who took it from the lips of Leverrier himself:—
Leverrier left Paris for Orgères, in company with Vallee, four days after the date of Lescarbault’s letter. Orgères was twelve miles from the nearest railroad-station, and the party had to foot it across the country. On their arrival, Leverrier knocked loudly at the door, which was opened by the doctor himself; but his visitor declined to give his name. The simple, modest, timid Lescarbault, small in stature, stood abashed before the tall Leverrier, who, in blunt intonation, addressed him thus: “It is you, then, sir, who pretend to have discovered the intra-Mercurial planet, and who have committed the grave offence of keeping your discovery secret for nine months! I come to do justice to your pretensions, to warn you that you have either been dishonest or deceived. Tell me unequivocally what you have seen.” The lamb-like doctor, trembling at this rude summons, stammered out the following reply:—
“On the 26th of March (1859), about four o’clock, I turned my telescope to the sun, when, to my surprise, I saw, at a small distance from its margin, a black spot, well defined, and perfectly round, advancing upon the disk of the sun. A customer called me away, and, hurrying him off as fast as I could, I came back to my glass, when I found the round spot had continued its transit, and I saw it disappear from the opposite margin of the sun, after a projection upon it of an hour and a half. I did not seize the precise moment of contact. The spot was on the disk when I first saw it. I measured its distance from the margin, and counted the time it took to make the same distance, and so approximated the instant of its entry.” “To count time is easy to say,” said Leverrier; “but where is your chronometer?” “My chronometer is this watch, that beats only minutes,—the faithful companion of my professional labors.” “What! with that old watch? How dare you talk of counting seconds? My suspicions are too well founded.” “Pardon me, sir, but I have a pendulum that nearly beats seconds, and I will bring it down to show you.” He goes above-stairs and brings down a silken thread, the upper end of which he fastens to a nail, and brings to rest the ivory ball at the lower end. He then starts it from the vertical, and its oscillations beat seconds very nearly. “This is not enough, sir: how do you count these seconds while in the act of observing?” “My profession is to feel pulses and count their pulsations, and my pendulum puts my seconds into my ears, and I have no difficulty in counting them.”
“But where is your telescope?” The doctor showed Leverrier his glass, which was one of Cauchoix’s best. It was four inches in diameter, and mounted on a rude stand. He took the wondering astronomer-imperial to his roof, where he was building a rude revolving platform and dome. “This is all very well; but where is your original memorandum?” The doctor ran and got his almanac, or Connaissance des Temps, and in it he finds a square piece of paper, used as a marker, and on it, all covered with grease and laudanum, is the original memorandum! “But you have falsified the time of emergence. It is four minutes too late by this memorandum.” “It is; but the four minutes are the error of my watch, which I corrected by sidereal time, by the aid of this little telescope.”
“But how did you determine the two angular co-ordinates of the point of contact, of the entry and emergence of the planet, and how did you measure the chord of the arc between them?” Having explained the simple method which he pursued in the premises to the satisfaction of the astronomer, the latter next inquired after his rough drafts of calculation for determining the distance of the planet from the sun. “My rough draughts! Paper is scarce with us. I am a joiner as well as an astronomer. I write on my boards, and when I am done, I plane them off and begin again; but I think I have preserved them.” On visiting the shop, they found the board, with all its lines and numbers still unobliterated!
The Parisian savant was now convinced that Lescarbault had really seen the planet whose existence he had himself foretold. Turning to the amateur astronomer, he revealed his personality, and congratulated his humble brother on the magnificent discovery thus confirmed. It was the event in the Orgères physician’s life. Honors poured in upon him. The cross of the Legion of Honor was sent to him from Paris, and his name was at once enrolled in the lists of the leading scientific academies of Europe.
The new orb, whose revolution is performed in 19 days, 17 hours, has been felicitously named Vulcan. If objection be offered to the selection of names for the planets from “Olympus’ dread hierarchy,” it must at least be acknowledged that there is a peculiar fitness in their distribution.