He jerked in his chair with a start and a wrench, and held out his hand for the glass. The mixture, of a rich port-wine colour, frothed at the top.

“It looks,” he said, suddenly, “it looks—those bubbles—like a string of pearls winking at you—rather like the pearls round that young lady’s neck.” He turned again to the advertisement where the female in the dove-coloured corset had seen fit to put on all her pearls before she cleaned her teeth.

“Not bad, is it?” I said.

“Eh?”

He rolled his eyes heavily full on me, and, as I stared, I beheld all meaning and consciousness die out of the swiftly dilating pupils. His figure lost its stark rigidity, softened into the chair, and, chin on chest, hands dropped before him, he rested open-eyed, absolutely still.

“I’m afraid I’ve rather cooked Shaynor’s goose,” I said, bearing the fresh drink to young Mr. Cashell. “Perhaps it was the chloric-ether.”

“Oh, he’s all right.” The spade-bearded man glanced at him pityingly. “Consumptives go off in those sort of doses very often. It’s exhaustion… I don’t wonder. I dare say the liquor will do him good. It’s grand stuff,” he finished his share appreciatively. “Well, as I was saying—before he interrupted—about this little coherer. The pinch of dust, you see, is nickel-filings. The Hertzian waves, you see, come out of space from the station that despatches ’em, and all these little particles are attracted together—cohere, we call it—for just so long as the current passes through them. Now, it’s important to remember that the current is an induced current. There are a good many kinds of induction——”

“Yes, but what is induction?”

“That’s rather hard to explain untechnically. But the long and the short of it is that when a current of electricity passes through a wire there’s a lot of magnetism present round that wire; and if you put another wire parallel to, and within what we call its magnetic field—why then, the second wire will also become charged with electricity.”

“On its own account?”