The work was hard and he had not expected Charnock's assistant to continue his task longer than he need.

Festing was fastidiously just, and thought it shabby to steal a workman's time; moreover, he imagined that if he had asked the fellow to go on after the whistle blew he would have refused.
Curiosity led him to wait farther along the track until the thud of the hammer stopped.

It looked as if Charnock was putting in the dynamite, and Festing hoped he would be careful with the detonator.

By and by he heard a warning shout, and a moment or two afterwards saw a blaze of light.

Then there was a curious sharp report, and pieces of broken rock splashed into the river.