The boys felt like Mercuries, with winged heels, so swiftly their skate-blades bore them onward. Before they had uttered another word they were at the head of Eagle Island. Here they had the choice of taking Paper-mill Slough, or continuing upon the river proper.

“Let’s go outside the island,” suggested Ned. “They say the water that comes from the paper-mill is so warm it eats away the ice, and that the slough’s chuck-full of air-holes.”

Ned’s picture was enough to remove any question as to routes, and down along the outside of the island they dashed, their skates clinking a merry tune.

At first they followed, as Ned had assured his father they could, a “regular path,” made by the skate-blades of numerous others. They met nobody save three or four Hollanders from the island settlement; odd-looking people on wooden skates, bound, with easy, graceful motion, for town.

The tracks dwindled and dwindled, and presently there were none at all. Not a person was in sight. Before the three lay the vast expanse of ice, waiting to be explored.

What had become of those reputed marks of Lou Ravens and “Duke” Burke, the frozen river said not, and the boys spent no time in searching.

Stillness reigned, broken only by the wood chopper’s ax echoing from the island, the cawing of the black crows crossing overhead, the metallic rhythm of the skate-blades, and the rumbling groans of the ice as it cracked for miles under the grip of the cold.

“My—isn’t this fine!” cried Hal, spurting to relieve his spirits.

“I should say so!” agreed both his comrades, spurting also.

For a quarter of a mile they fairly flew.