“Oppose, sir,” answered Michel Ardan, with perfect gallantry—“oppose as much as you like.”
“You know,” said the unknown, “that when the sun’s rays traverse a medium like air they are deviated from a straight line, or, in other words, they are refracted. Well, when stars are occulted by the moon their rays, on grazing the edge of her disc, do not show the least deviation nor offer the slightest indication of refraction. It follows, therefore, that the moon can have no atmosphere.”
Everyone looked at the Frenchman, for, this once admitted, the consequences were rigorous.
“In fact,” answered Michel Ardan, “that is your best if not only argument, and a savant, perhaps, would be embarrassed to answer it. I can only tell you that this argument has no absolute value because it supposes the angular diameter of the moon to be perfectly determined, which it is not. But let us waive that, and tell me, my dear sir, if you admit the existence of volcanoes on the surface of the moon.”
“Extinct volcanoes, yes; volcanoes in eruption, no.”
“For the sake of argument let us suppose that these volcanoes have been in eruption for a certain period.”
“That is certain, but as they can themselves furnish the oxygen necessary for combustion the fact of their eruption does not in the least prove the presence of a lunar atmosphere.”
“We will pass on, then,” answered Michel Ardan, “and leave this series of argument and arrive at direct observation. But I warn you that I am going to quote names.”
“Very well.”
“In 1715 the astronomers Louville and Halley, observing the eclipse of the 3rd of May, remarked certain fulminations of a remarkable nature. These jets of light, rapid and frequent, were attributed by them to storms in the atmosphere of the moon.”
“In 1715,” replied the unknown, “the astronomers Louville and Halley took for lunar phenomena phenomena purely terrestrial, such as meteoric or other bodies which are generated in our own atmosphere. That was the scientific aspect of these facts, and I go with it.”
“Let us pass on again,” answered Ardan, without being confused by the reply. “Did not Herschel, in 1787, observe a great number of luminous points on the surface of the moon?”
“Certainly; but without explaining the origin of these luminous points. Herschel himself did not thereby conclude the necessity of a lunar atmosphere.”
“Well answered,” said Michel Ardan, complimenting his adversary; “I see that you are well up in selenography.”
“Yes, sir; and I may add that the most skilful observers, MM. Boeer and Moedler, agree that air is absolutely wanting on the moon’s surface.”
A movement took place amongst the audience, who appeared struck by the arguments of this singular personage.
“We will pass on again,” answered Michel Ardan, with the greatest calmness, “and arrive now at an important fact. A skilful French astronomer, M. Laussedat, whilst observing the eclipse of July 18th, 1860, proved that the horns of the solar crescent were rounded and truncated. Now this appearance could only have been produced by a deviation of the solar rays in traversing the atmosphere of the moon. There is no other possible explanation of the fact.”
“But is this fact authenticated?”
“It is absolutely certain.”
An inverse movement brought back the audience to the side of their favourite hero, whose adversary remained silent.
Ardan went on speaking without showing any vanity about his last advantage; he said simply—
“You see, therefore, my dear sir, that it cannot be positively affirmed that there is no atmosphere on the surface of the moon. This atmosphere is probably not dense, but science now generally admits that it exists.”
“Not upon the mountains,” replied the unknown, who would not give in.
“No, but in the depths of the valleys, and it is not more than some hundreds of feet deep.”
“Anyway you will do well to take your precautions, for the air will be terribly rarefied.”
“Oh, there will always be enough for one man. Besides, once delivered up there, I shall do my best to economise it and only to breathe it on great occasions.”
A formidable burst of laughter saluted the mysterious interlocutor, who looked round the assembly daring it proudly.
“Then,” resumed Michel Ardan, carelessly, “as we are agreed upon the presence of some atmosphere, we are forced to admit the presence of some water—a consequence I am delighted with, for my part. Besides, I have another observation to make. We only know one side of the moon’s disc, and if there is little air on that side there may be much on the other.”
“How so?”
“Because the moon under the action of terrestrial attraction has assumed the form of an egg, of which we see the small end. Hence the consequence due to the calculations of Hausen, that its centre of gravity is situated in the other hemisphere. Hence this conclusion that all the masses of air and water have been drawn to the other side of our satellite in the first days of the creation.”
“Pure fancies,” exclaimed the unknown.
“No, pure theories based upon mechanical laws, and it appears difficult to me to refute them. I make appeal to this assembly and put it to the vote to know if life such as it exists upon earth is possible on the surface of the moon?”
Three hundred thousand hearers applauded this proposition. Michel Ardan’s adversary wished to speak again, but he could not make himself heard. Cries and threats were hailed upon him.
“Enough, enough!” said some.
“Turn him out!” repeated others.
But he, holding on to the platform, did not move, and let the storm pass by. It might have assumed formidable proportions if Michel Ardan had not appeased it by a gesture. He was too chivalrous to abandon his contradicter in such an extremity.
“You wish to add a few words?” he asked, in the most gracious tone.
“Yes, a hundred! a thousand!” answered the unknown, carried away, “or rather no, one only! To persevere in your enterprise you must be—”
“Imprudent! How can you call me that when
