Table showing whether a Vessel gains or loses by keeping away a given number of Points from the True Course, thereby enabling her to economize Fuel.

The upper line shows the rate in knots per hour steaming head to wind. The other lines show the rate in knots a ship must go, if she keeps away, to be in as good a position as she would have been had she held on her course.

Example.-A ship is able to steam 4 knots an hour head to wind; by keeping away 4 points, and setting fore-and-aft sails, she makes 6 knots an hour. The table shows that if she made 5.65 knots, she would be in as good a position as if she had remained steering head to wind; therefore, if she can steam 6 knots, she gains nearly half a knot an hour; but if she can only steam and sail at the rate of 5 knots, she is losing.

If the vessel keeps away 5 points she must steam or sail at the rate of 7.2 knots to be in an equally good position.