been undermined with vast conduits, sewers,
and tunnels, and that these communicated with the sea". It had been much
disputed whether the sea did or did not still send its tides up to the
site of the old quays. Felix now thought that the explosions were due to
compressed air, or more probably to gases met with by the ascending
tide.

CHAPTER XXV

THE SHEPHERDS

For four days Felix remained on the island recovering his strength. By
degrees the memory of the scenes he had witnessed grew less vivid, and
his nerves regained their tone. The fifth morning he sailed again,
making due south with a gentle breeze from the west, which suited the
canoe very well. He considered that he was now at the eastern extremity
of the Lake, and that by sailing south he should presently reach the
place where the shore turned to the east again. The sharp prow of the
canoe cut swiftly through the waves, a light spray flew occasionally in
his face, and the wind blew pleasantly. In the cloudless sky swallows
and swifts were wheeling, and on the water half a dozen mallards moved
aside to let him pass.

About two hours after he started he encountered a mist, which came
softly over the surface of the water with the wind, and in an instant
shut out all view. Even the sun was scarcely visible. It was very warm,
and left no moisture. In five minutes he passed through and emerged
again in the bright sunlight. These dry, warm mists are frequently seen
on the Lake in summer, and are believed to portend a continuance of fine
weather.

Felix kept a good distance from the mainland, which was hilly and
wooded, and with few islands. Presently he observed in the extreme
distance, on his right hand, a line of mountainous hills, which he
supposed to be the southern shore of the Lake, and that he was sailing
into a gulf or bay. He debated with himself whether he should alter his
course and work across to the mountains, or to continue to trace the
shore. Unless he did trace the shore, he could scarcely say that he had
circumnavigated the Lake, as he would leave this great bay unexplored.
He continued, therefore, to sail directly south.

The wind freshened towards noon, and the canoe flew at a great pace.
Twice he passed through similar mists. There were now no islands at all,
but a line of low chalk cliffs marked the shore. Considering that it
must be deep, and safe to do so, Felix bore in closer to look at the
land. Woods ran along the hills right