Every pilot, within such convenient time as the commissioners may direct, who has control over the waters within which he acts, shall furnish himself with a good telescope or spyglass, under the penalty of fifty dollars ($50.00), to be paid to the commissioners. (1790, c. 320, s. 3; R.C., c. 85, s. 27; Code, s. 3517; Rev., s. 4973; C.S., s. 6987.)