"Why did you select boys?"
"Because all the others were born in an atmosphere of superstition and reared in it. It is in their blood and bones. We imagined we had educated it out of them; they thought so, too; the Interdict woke them up like a thunderclap! It revealed them to themselves, and it revealed them to me, too. With boys it was different. Such as have been under our training from seven to ten years have had no acquaintance with the Church's terrors, and it was among these that I found my fifty-two. As a next move, I paid a private visit to that old cave of Merlin's-not the small one-the big one-"
"Yes, the one where we secretly established our first great electric plant when I was projecting a miracle."
"Just so. And as that miracle hadn't become necessary then, I thought it might be a good idea to utilize the plant now. I've provisioned the cave for a siege-"
"A good idea, a first-rate idea."
"I think so. I placed four of my boys there as a guard-inside, and out of sight. Nobody was to be hurt-while outside; but any attempt to enter-well, we said just let anybody try it! Then I went out into the hills and uncovered and cut the secret wires which connected your bedroom with the wires that go to the dynamite deposits under all our vast factories, mills, workshops, magazines, etc., and about midnight I and my boys turned out and connected that wire with the cave, and nobody but you and I suspects where the other end of it goes to. We laid it under ground, of course, and it was all finished in a couple of hours or so. We sha'n't have to leave our fortress now when we want to blow up our civilization."
"It was the right move-and the natural one; military necessity, in the changed condition of things. Well, what changes have come! We expected to be besieged in the palace some time or other, but -however, go on."
"Next, we built a wire fence."
"Wire fence?"
"Yes. You dropped the hint of it yourself, two or three years ago."
"Oh, I remember-the time the Church tried her strength against us the first time, and presently thought it wise to wait for a hopefuler season. Well, how have you arranged the fence?"
"I start twelve immensely strong wires-naked, not insulated -from a big dynamo in the cave-dynamo with no brushes except a positive and a negative one-"
"Yes, that's right."
"The wires go out from the cave and fence in a circle of level ground a hundred yards in diameter; they make twelve independent fences, ten feet apart-that is to say, twelve circles within circles-and their ends come into the cave again."
"Right; go on."
"The fences are fastened to heavy oaken posts only three feet apart, and these posts are sunk five feet in the ground."
"That is good and strong."
"Yes. The wires have no ground-connection outside of the cave. They go out from the positive brush of the dynamo; there is a ground-connection through the negative brush; the other ends of the wire return to the cave, and each is grounded independently."
"No, no, that won't do!"
"Why?"
"It's too expensive-uses up force for nothing. You don't want any ground-connection except the one through the negative brush. The other end of every wire must be brought back into the cave and fastened independently, and without any ground-connection. Now, then, observe the economy of it. A cavalry charge hurls itself against the fence; you are using no power, you are spending no money, for there is only one ground-connection till those horses come against
