Such was the harvest of facts and ideas garnered from Mars at the Observatory during this summer of tireless watching. Both the facts and the conclusions drawn from them were received with incredulity by astronomers whose atmospheres and unfamiliarity with the things to be observed hindered their seeing the phenomena, and to whom the explanations seemed fantastic. With more careful observation skepticism about the phenomena decreased, one observer after another seeing the change of color on the planet, the growth of vegetation, and in some form the lines and the dots, although many skilled observers still see them as irregular markings rather than as fine uniform lines. The hypothesis of artificial construction of the canals by intelligent beings has met with much more resistance. It runs against the blade of Occam’s razor, that nothing should be attributed to conscious intelligent action unless it cannot be explained by natural forces. Percival seems to have made a very strong argument against any natural cause yet suggested, and a rational case for an intelligent agency if no natural one can be found. There, for the present, his hypothesis may be said to rest.
The favorable period for observation during the opposition of Mars having come to an end, the two larger telescopes, which had been hired or borrowed for the expedition, were returned in the spring to their owners, the observatory at Flagstaff being dismantled, and the rest of the apparatus brought East and stored; but plans for further work on Mars were by no means given up; and Percival—bent on still better equipment for the next opposition of Mars, in the summer of 1896—arranged with Alvan Clark & Sons for the manufacture of a 24-inch refractor lens. The Clarks were then the most successful makers of large lenses in the world; for up to that time it had not been possible to cast and cool these large pieces of glass so that they were perfectly uniform in density, and the art of the Clarks consisted in grinding and rubbing the surface so as to make its slight departure from the calculated curves compensate for any unevenness in density; and to a less extent it is still necessary. It required a skill of eye and hand unequalled elsewhere, and Percivals’ lens was one of the most perfect they ever made.
Where the telescope should be set up was not yet decided; for it will be remembered that he wanted to make his observations in any accessible place in the world where the clearest, and especially the steadiest, atmosphere would be found. As already explained, he believed this lay in one of the two great desert belts that encircle the Earth north and south of the equator; and, for practical purposes, that meant Arizona, Mexico and South America in the Western Hemisphere, and the Sahara in the Eastern. Mr. Douglass had therefore been sent—probably with the faithful 6-inch telescope—to Mexico and South America, while Percival proposed to examine the Sahara himself.
CHAPTER XI
THE PERMANENT OBSERVATORY—INTERLUDES AND TRAVELS
The year following his return to Boston, at the end of November, 1894, was filled with the arrangements for his new telescope and apparatus, and in writing the book on Mars. At this time he lived at 11 West Cedar Street, the little house he had bought some time before; for it was characteristic that, while lavishing whatever was needed on his observatory, he was modest in his expenditure on himself. By the end of the year his book was published, his work for the coming observatory was done, and he went to Europe; but his Mother had died in March, and the daily stream of loving letters, which told about himself, had ceased to flow.
On December 10, 1895, he sailed on the Spree with Alvan G. Clark, the last surviving brother of the telescope-making family. The voyage, though very rough at times, was uneventful, until as they were entering the Solent the vessel struck, and stuck fast, on Warden’s Ledge, just inside the Needles. “Fault of the pilot” Percival recorded, “aged 73 and bordering on imbecility.” With all his travels about and around the world this is the nearest he ever came to shipwreck; nor was it for him very near, for since the ship could not get herself clear tugs came down the next day and took off the passengers, who were landed at Southampton and went up to London. Two days later he was in Paris, and for nearly three weeks he and Clark saw astronomical friends,—among others having to lunch and dinner Edouard Mantois, the great glass manufacturer who had cast the new 24-inch refractor for his telescope. Percival enjoyed a most interesting dinner at the house of Flammarion, the astronomer and novelist, who was devoted to Mars and had followed his work at Flagstaff. As he wrote to his Father—“There were fourteen of us, and all that could sat in chairs of the zodiac, under a ceiling of a pale blue sky, appropriately dotted with fleecy clouds, and indeed most prettily painted. Flammarion is nothing if not astronomical. His whole apartment, which is itself au cinquieme, blossoms with such decoration.
“At the dinner I made the acquaintance of Miss Klumpke of the Paris Observatory, who has just translated my last article for the Bulletin of the Société Astronomique.”
In fact before he left Paris for Africa he gave a talk to that society, on his observations of Mars. At Marseilles, meeting his old friend, Ralph Curtis, they crossed to Algiers and made excursions to Boghari and Biskra to test the atmosphere on the border of the Sahara. Not finding this satisfactory, he organized a small private caravan of his own for a journey of a few days into the desert, taking the telescope—doubtless the faithful six-inch—on a mule. His going off by himself across country seems to have worried his companions for fear he would lose his way; but he always turned up in the afternoon, and in time to observe when the stars came out. Curiously enough, he found that although the air was very clear they twinkled badly, so that while the atmosphere was transparent it was distinctly unsteady, for his purpose a very grave defect which excluded North Africa from the possible sites for his observatory. Satisfied on this point, he left Algiers in February.
From Marseilles he took the opportunity to visit Schiaparelli, to whom he owed so much of the incentive to study Mars, and found him at his observatory in Brera near Milan. With him he compared observations, much to his own satisfaction. The veteran looked middle-aged, but did not expect to make more discoveries, and said that at the preceding opposition the weather had been so bad that he saw almost nothing. So his mantle had definitely fallen on Percival when he began his observations at Flagstaff the year before.
Leaving Milan he started to visit Leo Brenner, who was also interested in Mars, and had his observatory at Lussinpiccolo, a rather inaccessible spot on the eastern coast of the Adriatic. In getting there he was much delayed by a heavy storm, and beguiled the time by working out a mathematical theory of the tides. Finally, he decided to go by rail to Pola, and thence by boat to Lussinpiccolo, where Brenner met him, insisting that he should stay with them. They proved most hospitable and kind, but he was not favorably impressed by the observatory or its work; and after a stay of a few days he returned through Cannes, Paris and London, sailing for America on March 19th, to land in New York on the 28th.