"Now I will lift the drill up gently, Bertie; do you kneel down, and when I stop, take hold of it close to the floor, so that we may see the thickness of the stone."
"Five inches," he said as he measured it. "Now put on a little grease, Dias. I will lower it again, and we shall be perhaps able then to get some idea of what is underneath."
He lowered the drill and turned it round two or three times, and then carefully raised it. Some sand and little stones were sticking to it.
"Sand and gravel," he said. "That settles that point. Now we have done a good morning's work, and let us go up and have breakfast."
Maria looked enquiringly at them. "I was just coming down for you. Well, what have you done?"
"We have drilled one hole, Maria, and none of us have got our fingers smashed, so I think we have every reason to be satisfied with our first experience at the work."
As they breakfasted they talked matters over. Harry said that he was certain that the thickness of the stone was not sufficient for them to break it up by blasting. "We shall have to try some other plan. It is equally certain that we cannot smash the stone with the sledge-hammers, and I don't think that the wedges would break it. Of course if we got one stone out it would be comparatively easy to lift the next, as we could put the crowbars under it. If we can do it in no other way, we must drill a line of holes close to each other right across the stone, and we might then break off the piece between them and the crack and get our crowbars under the slab. It might be worth while to drill holes a foot apart, from the point where we have begun to the other end of the room. Of course if we found that gravel and stones were everywhere under the slabs we should learn nothing; but the opening to the chambers is probably covered by another stone, and if we found that, we could put in one or two more holes so as to be sure that it was flat, in which case we might smash it somehow. Of course, if we don't come upon a flat stone we shall conclude that they put a layer of sand and fine gravel over the slabs covering the vaults, and must then, as I say, get up one stone and gradually lift all the rest, clearing out the gravel as we go to the depth of a foot or so. In that way we shall make sure that we shall not miss any chamber there may be.
"I think that would certainly be the best plan. At present we are groping altogether in the dark, and it will take us a fortnight at least to make that row of holes close to each other, as you propose."