the Flatiron was now entirely concealed by the dense forest.

Soil had formed thickly over all the surface. Huge oaks and pines
flourished there as confidently as though in the heart of the Maine
forest, crowding ash and beech for room.

Under the man's feet, even as he stood close by the building--which
was thickly overgrown with ivy and with ferns and bushes rooted in the
crannies--the pine-needles bent in deep, pungent beds.

Birch, maple, poplar and all the natives of the American woods
shouldered each other lustily. By the state of the fresh young leaves,
just bursting their sheaths, Stern knew the season was mid-May.

Through the wind-swayed branches, little flickering patches of morning
sunlight met his gaze, as they played and quivered on the forest moss
or over the sere pine-spills.

Even upon the huge, squared stones which here and there lay in
disorder, and which Stern knew must have fallen from the tower, the
moss grew very thick; and more than one such block had been rent by
frost and growing things.

"How long has it been, great Heavens! How long?" cried the engineer, a
sudden fear creeping into his heart. For this, the reasserted
dominance of nature, bore in on him with more appalling force than
anything he had yet seen.

About him he looked, trying to get his bearings in that strange
milieu.