The walls and roof were likewise composed of stone and covered with cement, while at regular intervals along the ceiling were electric globes, which gave them plenty of light.
They went down about forty of these stone steps before they came to level ground, and then, before them, they saw a long, straight, and well-lighted lobby with an arched roof.
"This is the secret of the Three Ace Club. We have to take precautions when we have the like of Oom Paul to deal with," remarked Philip, with a smile. "Here you may make as much noise as you like, for no one outside could hear even a gun report. We have stopped the echo."
"It must have cost something to excavate this vault," said the boys.
"Yes; a good deal of Rand money has been sunk here. But come and see our shooting-gallery, arsenal, and general meeting-place."
He led the way along the lobby until they came to a door, against which he gave three loud knocks, at the same time pressing a knob.
Immediately the door opened, and they entered.
An underground hall of four hundred feet spread before them, in which were assembled a number of men.
It was lighted like the lobby by electricity, and lined, floor, coiling, walls, and doors, with felt. At the far end were placed three targets, and all round on racks, from floor to ceiling, were rifles. Not thirty thousand, but over a hundred thousand weapons, were here placed ready for use.
Along two sides were placed a row of maxim guns. Ted counted thirty to each side. He also noticed that there were several doors at different parts of this vast gallery.
Philip Martin saw their amazement, and smiled again.
"You see we are not altogether so much at the mercy of the Boers as they fondly imagine. That door to your right leads off to our magazine, where we have sufficient ammunition for our purpose. That other door on your left leads to a tunnel which we are at present engaged in boring. When finished it will take us into the fort where Kruger has fixed his Krupps. We are more than two-thirds on the way now. Those other doors are exits, and lead to different parts of the city. Oh yes, when next we rise, if we are forced, it shall not be against our wives and children that the fort guns will be discharged. We'll use them for another purpose, and be much obliged to Oom Paul for his valuable gift."