At that moment Sir William came towards her. He had switched on the electric light, and the room was now brilliantly illuminated. In his hand he held a large oval thing of brass, bright and shining.
At that moment, also, old Lady Poole woke up with a start.
"Dear me," she said, "I must have taken forty winks. Well, I suppose, my dear children, that I have proved my absolute inability to be de trop! What are you doing, William?"
"It's a little experiment," Sir William said, "one of my inventions, Lady Poole. Marjorie, I want you to take off your hat."
Marjorie did so. With careful and loving hands the great man placed the metal helmet upon her head. The girl let him do so as if she were in a dream. Then Sir William pressed a button in the wall. In a few seconds there was an answering and sudden ring of an electric bell in the study.
"Now, Marjorie!" Sir William said, "now, all I have told you is being actually proved."
He looked at her face, which flowered beneath the grotesque and shining cap of metal.
"Now, Marjorie, everything you are thinking is being definitely recorded in another place."
For a moment or two the significance of his words did not penetrate to her mind.
Then she realized them.