Once clear of the ice, the floating sleigh was headed northwards, the aerial propellers were brought into action, and at a speed of twenty-five knots the unique craft glided with a hydroplane-like motion over the waves.
[Illustration: The Bird of Freedom toppled, and like an arrow, plunged into the sea.
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Leslie was now at liberty to "stand easy." There was no immediate or apparent reason why the motors should be stopped or slowed down during the sea passage, unless small floes, rising sufficiently high out of the water, were encountered. Then the danger would arise of the aerial propellers striking the obstruction; hence to prevent such a possibility it would be necessary to use the marine propeller only.
Ranworth's decision to make use of the twin aerial propellers was determined solely by a desire to attain the greatest possible speed. In conjunction with the marine propeller, an increase of 25 per cent. in speed was obtainable.
"Going jolly well now, Leslie," observed Ranworth, enthusiastically, as the lad joined him at the foremost observation scuttle. "'Pon my word, you've managed to get a bit out of the motors."
"They're not going so badly," admitted Leslie modestly.
"It occurred to me that we ought to give the sleigh a name," continued Ranworth. "I've come to the conclusion that the word 'sleigh' is not sufficiently appropriate. What we have is really a combined cabin-boat on runners or wheels, or floating on the water according to circumstances. Hence, since she's a sort of boat, she ought to be named, Now, what do you suggest?"
"It's rather hard lines that the responsibility of giving her a name should rest with me, sir," objected Leslie, laughingly.