This is placed near enough so that the steersman can hear the man who "heaves the lead" when he calls out the number of fathoms of water.

This he tells by the marks on the "lead line" as follows: 2 fathoms, twelve feet, 2 strips of leather.
3 " 3 strips of leather.
5 " white rag.
7 " red rag.
10 " leather with hole in it.
13 " 3 strips of leather or blue rag.
15 " white rag.
17 " red rag.
20 " 2 knots.
25 " 1 knot.
30 " 3 knots.
35 " 1 knot.
40 " 4 knots.
9 " are called mark.
11 " " " deeps.
The leadsman stands on his little grating and swings the lead so it just clears the water.

When it is swinging well he lets it fly in the direction in which the ship is moving and then notes the depth by the strips of leather or rags.

The result is shouted out so the steersman can hear and keep the vessel in the channel.
THE BOATSWAIN'S CALLS.
The boatswain's calls or "pipes" are very difficult to reduce to a musical scale, because the pitch of the instrument depends entirely on the amount of energy expended by the blower.

The novice, after a few trials, would probably assert that the primitive little whistle had only one note--and not very much of that; but he would be surprised indeed at the volume of sound, the range, and the command over the instrument which a veteran boatswain would soon make everyday matter to him.