"There's a threat of thunder and I'd like to cross the lake before the storm comes." Agatha got up and in a few minutes they launched the canoes.

The heat was overwhelming and Agatha felt no movement of the air, but the _Metis_ sweated and panted as they labored at the paddles.

The thud of the blades came back in measured echoes from the motionless pines and a fan-shaped wake trailed far across the glassy lake.

In the meantime, the cloud bank rolled up the sky like a ragged arch and covered the sun.

The glare faded and a thick, blue haze crept out upon the water, until it looked as if the horizon advanced to meet them, but the heat did not get less.