"You will need all your eyes to see much of the shore now," he said; "I have given her her wings."

Nitocris felt a shudder in the carpeted floor. Looking ahead she saw the bow lift slightly. Then a smooth, green swathe of water curled up on either side. She looked aft, and saw a broad torrent of froth, foaming like a furious, rapid stream away from the stern. The houses and trees on the shore seemed to run into each other, and slide out of sight almost before the eye could rest upon them. The water alongside was merely a blue-green blur. Nitocris involuntarily held her breath as though she had been out on deck.

"It is wonderful, Prince!" she said, almost in a whisper. "That alleged express from Hamburg was nothing to this: and yet how steadily she moves in spite of the speed. I should have thought that it would have nearly shaken us to jelly."

"That is the turbines, dear," said her father, who was already wondering whether Oscarovitch was doing this just to show how hopeless any pursuit of such a vessel would be. "They are a marvellous means of applying steam power. Lieutenant Parsons is robbing the sea of one, at least, of its worst terrors."

"Yes," added the Prince, "we are travelling a little over forty miles an hour; and if you got that speed out of reciprocating engines you would scarcely be able to lie on the deck without holding on to something, yet here we are as comfortable as though we were standing in a drawing-room."

"You have given us a new experience to begin with," said Nitocris, thinking how nice it would be to take her wedding trip with Merrill in such a craft as this. "Why, look at the two shores coming together, Dad!"

"No, excuse me," said Oscarovitch, "we are only about half-way to the Gate of the Baltic yet. That land on the right is the island of Hvreen. When we have passed that you will soon see the heights of Elsinore and Helsingborg rising ahead. There are only about two and a half miles between Denmark and Sweden there."

"Oh yes, of course. I am forgetting my geography," laughed Nitocris, as the low, wooded patch of land came rushing towards them as though it were adrift on a fast-flowing stream. "Goodness, what a speed!"

"A very wonderful craft, Prince," added the Professor, as the island drifted past; "she quite inclines me towards a breach of the tenth commandment. Now that you have given us this taste of the delights of speed, I think that if I were a millionaire, I should try to build one to beat her."

"Exactly," laughed Oscarovitch. "It is marvellous this fascination of speed. Your poet, Henley, touched the pulse of the times when he wrote those splendid lines of his. But surely, Professor, you would not have very much difficulty in leaving all far behind. A man to whom mathematical impossibilities are as easy as an addition sum ought to be able to realise the dream of the ages and solve the problem of aerial navigation."