No.
As they reached the bottom, the two boys, momentarily deprived of their senses by the fall, were partially restored by the shock.
Instinctively the knives go to work.
Young Jack here rendered the most signal service.
He held his knife in a tight grip even as they fell.
And barely did they come in contact with the bed of the ocean, when young Jack stabbed upwards, and, at a single stroke, cut his way out of the sack.
At the self-same instant his left hand grappled his friend and trusty comrade Harry.
To kick the earth fiercely with his feet was to Jack a natural impulse, and striking upwards, he made for the surface.
Will he reach it?
Doubtful.