leadsman

He slowed the freighter to a snail's pace when he approached the dredged channel, and at last the leadsman found suitable bottom.

At a signal the leadsman had flown his pigeon again, though we were well past all reefs.

Then came the leadsman's long-drawn chant, once so familiar, the monotonous repeating in river parlance of the depths of water.

A leadsman had been stationed on each side of the forecastle, though there was no present occasion for their services.

The leadsman was ordered to sound, as the screw was stopped, and he reported sixteen fathoms with the deep-sea lead.