Yet it is a point which must be insisted upon before pursuing our terrestrial investigations further, that whatever may be the variety of stellar systems, the differences of volume, temperature, density, illumination, electrification, movement, chemical constitution, etc., of the various globes which people the immensity of the universe, all these worlds are linked amongst themselves by the same invisible and imponderable Power which combines them all in a network of extreme sensitiveness. The prodigious extent of the distances which separate these systems one from the other does not prevent their being connected together by some sort of maternal link. The distance from the Earth to the Moon is 240,000 miles. The Moon acts constantly upon all the molecules of our globe and upon the entire Earth, and every one of us weighs a little less when that body shines over our heads than when it is on the horizon. The distance from the Sun to the Earth is 92 million miles; the Sun makes our planet move with a speed corresponding to that distance, and the Earth in its turn displaces the Sun in the heavens. The distance from the Sun to Neptune is over 2,500 million miles. The central globe acts upon that distant world and makes it revolve round it, and on the other hand Neptune makes the Sun revolve round their common centre of gravity, which is at a distance of 144,000 miles from the centre of the Sun. Jupiter displaces the Sun by 460,000 miles, and Saturn by 25,000 miles. The Moon disturbs the Earth to the extent of 2,900 miles. At the same time Jupiter acts upon the Earth, the Earth upon Venus, and so on. On account of this reciprocal influence of all the heavenly bodies upon each other, not a single point can remain in repose for an instant, and no heavenly body can ever come back to the place it previously occupied. All that we call matter is in perpetual motion under the irresistible power of invisible, intangible, and imponderable force. We have here a fact of capital importance, the consideration of which must always be associated with the conception we can form of the real nature of the universe. We have seen just now that the distance which separates our Sun from the star Alpha Centauri is 25 billion miles. But this distance is traversed by gravitational attraction. In reality the two suns are not absolutely separated. They know each other, they feel each other’s attraction, and they feel the attraction of all the other suns of infinite space. They both roam about, our own Sun with a speed calculated at about 200 million miles per annum and Alpha Centauri with a speed of approximately 400 million. The other suns of which we know the distance and the movement rush on with similar speeds. Some of them fly with incomparably greater velocities, which attain 200 miles a second, 11,000 miles per minute, 600,000 miles an hour, 15 million per day, and 5 or 6 thousand million miles per annum, veritable starry projectiles of the heavenly fields.