I examined everything closely and asked a hundred questions, but the doctor seemed to have provided for every necessity or contingency.
"Let us waste no more time," said I. "If we have forgotten anything, we must get along without it. All aboard! What is our first stop?"
"The planet Mars, only thirty-six million miles away, if we are successful in meeting him just as he comes into opposition on the third day of August. This is the most favourable opposition in which to meet him for the past quarter of a century. Back in the year 1877 he was only about thirty-five million miles away, and it was then that we learned most that we know of his physical features. But we shall not have a more favourable time than this for the next seventeen years."
"Still it seems like nonsense to talk about travelling such an incomprehensible distance, doesn't it?" I ventured.
"Not at all!" he replied positively. "If the Earth travels a million miles per day in her orbit, without any motion being apparent to her inhabitants, why should we not travel just as fast and just as unconsciously? We are driven by the same force. The same engine of the Creator's which drives all the universe, drives us. When we have left the atmosphere we shall rush through the void of space without knowing whether we are travelling at a thousand miles per minute or standing perfectly still. Our senses will have nothing to lay hold on to form a judgment of our rate of speed. But if we make an average of only five hundred miles per minute we shall accomplish the distance in about fifty days, and arrive soon after opposition."
"But have you given up stopping on the Moon?" I asked. "I had great hopes of making those rich discoveries there."
"We must leave all that until our return trip. I have chosen this starting time in the dark of the Moon in order to have the satellite on the other side of the Earth and out of the way. She would only impede our progress, as we wish to acquire a tremendous velocity just as soon as we leave the atmosphere. We must accelerate our speed as long as gravity will do it for us. When we can no longer gain speed, we shall at least continue to maintain our rapid pace.
"But if we stopped on the Moon, we should only have her weak gravity to repel us towards Mars, and we could make but little speed. On our return, the stop on the Moon will be a natural and easy one. We shall be near home and can afford to loiter."
While the doctor was saying this, he had been busy making tests of his apparatus. He now called me to see his buoyancy gauge, which was a half-spherical mass of steel weighing just ten pounds. It was pierced with a hole at right angles to its plane surface and strung upon a vertical copper wire. Small leaden weights, weighing from an ounce to four pounds each, were provided to be placed upon the plane surface of the steel. The doctor explained its action to me thus:—
"The polarizing action of the gravity apparatus affects only steel and iron, and has no effect upon lead. Therefore, when the current is conducted through the copper wire into the soft steel ball, it will immediately rise up the wire, by the repulsion of negative gravity. Now, if the leaden weights are piled upon the steel ball one by one, until it is just balanced half way up the wire, our buoyancy is thus measured or weighed. For instance, with the first two batteries turned in we have a buoyancy a little exceeding one pound. That means, we should rise with one-tenth the velocity that we should fall. Turning in two more batteries, you see the buoyancy is three pounds, or our flying speed will be three-tenths of our falling speed. With all the batteries acting upon the gauge, you see it will carry up more than ten pounds of lead, because the pressure of the air is against weight and in favour of buoyancy. So long as we are in atmospheres, then, it is possible to fall up more rapidly than to fall down; but, on account of friction and the resultant heat, it is not safe to do so."