“But I will do it,” said he to Margaret. “If this is a cavern, and if it has a bottom, I will reach it. I will go on and see what there is beyond. On such a discovery as I have made one can pass no conclusion whatever. If I cannot go farther, I need not have gone down at all.”
“No,” said Margaret, “I don't want you to go on—at least at present; you must wait. The earth will wait, and I want you to be in a condition to be able to wait also. You must now stop this work altogether. Stop doing anything; stop thinking about it. After a time—say early in winter—we can recommence operations with the Artesian ray; that is, if we think well to do so. You should stop this and take up something else. You have several enterprises which are very important and ought to be carried on. Take up one of them, and think no more for a few months of the nothingness which is fourteen miles below us.”
It was not difficult for Roland Clewe to convince himself that this was very good advice. He resolved to shut up his lens-house entirely for a time, and think no more of the great work he had done within it, but apply himself to something which he had long neglected, and which would be a distraction and a recreation to his disappointed mind.
CHAPTER XV. THE AUTOMATIC SHELL
In a large building, not far from the lens-house in which Roland Clewe had pursued the experiments which had come to such a disappointing conclusion, there was a piece of mechanism which interested its inventor more than any other of his works, excepting of course the photic borer.
This was an enormous projectile, the peculiarity of which was that its motive power was contained within itself, very much as a rocket contains the explosives which send it upward. It differed, however, from the rocket or any other similar projectile, and many of its features were entirely original with Roland Clewe.
This extraordinary piece of mechanism, which was called the automatic shell, was of cylindrical form, eighteen feet in length and four feet in diameter. The forward end was conical and not solid, being formed of a number of flat steel rings, decreasing in size as they approached the point of the cone. When not in operation these rings did not touch one another, but they could be forced together by pressure on the point of the cone. This shell might contain explosives or not, as might be considered desirable, and it was not intended to fire it from a cannon, but to start it on its course from a long semi-cylindrical trough, which would be used simply to give it the desired direction. After it had been started by a ram worked by an engine at the rear end of the trough, it immediately bean to propel itself by means of the mechanism contained within it.
But the great value of this shell lay in the fact that the moment it encountered a solid substance or obstruction of any kind its propelling power became increased. The rings which formed the cone on its forward end were pressed together, the electric motive power was increased in proportion to the pressure, and thus the greater the resistance to this projectile the greater became its velocity and power of progression, and its onward course continued until its self-containing force had been exhausted.
The power of explosives had reached, at this period, to so high a point that it was unnecessary to devise any increase in their enormous energy, and the only problems before the students of artillery practice related to methods of getting their projectiles to the points desired. Progress in this branch of the science had proceeded so far that an attack upon a fortified port by armored vessels was now considered as a thing of the past; and although there had been no naval wars of late years, it was believed that never again would there be a combat between vessels of iron or steel.