In fact, it being admitted that the bullet would describe an orbit round the moon, that orbit must necessarily be elliptical. Science proves that it must be thus. No mobile circulation round any body is an exception to that law. All the orbits described in space are elliptical, those of satellites round their planets, those of planets around their sun, that of the sun round the unknown orb that serves as its central pivot. Why should the projectile of the Gun Club escape that natural arrangement? Now in elliptical orbits attracting bodies always occupy one of the foci of the ellipsis. The satellite is, therefore, nearer the body round which it gravitates at one moment than it is at another. When the earth is nearest the sun she is at her perihelion, and at her aphelion when most distant. The moon is nearest the earth at her perigee, and most distant at her apogee. To employ analogous expressions which enrich the language of astronomers, if the projectile remained a satellite of the moon, it ought to be said that it is in its "aposelene" at its most distant point, and at its "periselene" at its nearest. In the latter case the projectile ought to attain its maximum of speed, in the latter its minimum. Now it was evidently going towards its "aposelene," and Barbicane was right in thinking its speed would decrease up to that point, and gradually increase when it would again draw near the moon. That speed even would be absolutely _nil_ if the point was coexistent with that of attraction. Barbicane studied the consequences of these different situations; he was trying what he could make of them when he was suddenly interrupted by a cry from Michel Ardan. "I'faith!" cried Michel, "what fools we are!" "I don't say we are not," answered Barbicane; "but why?" "Because we have some very simple means of slackening the speed that is taking us away from the moon, and we do not use them." "And what are those means?" "That of utilising the force of recoil in our rockets." "Ah, why not?" said Nicholl. "We have not yet utilised that force, it is true," said Barbicane, "but we shall do so." "When?" asked Michel. "When the time comes. Remark, my friends, that in the position now occupied by the projectile, a position still oblique to the lunar disc, our rockets, by altering its direction, might take it farther away instead of nearer to the moon. Now I suppose it is the moon you want to reach?" "Essentially," answered Michel. "Wait, then. Through some inexplicable influence the projectile has a tendency to let its lower end fall towards the earth. It is probable that at the point of equal attraction its conical summit will be rigorously directed towards the moon. At that moment it may be hoped that its speed will be _nil_. That will be the time to act, and under the effort of our rockets we can, perhaps, provoke a direct fall upon the surface of the lunar disc." "Bravo!" said Michel.