‘Navigation demonstrateth how, by the shortest good way, by the aptest direction, and in the shortest time a sufficient ship between any two places may be conducted.’ To our Elizabethan forebears it was evident that the best way to conduct a ship was by the shortest passage of time which engendered least risk of catastrophe and avoided excessive wear and tear on ship, equipment and possibly passengers and crew. In the age of value-engineering and cost-effectiveness we are required to quantify these conflicting criteria. This is a matter of economics, which is concerned with applying the finite resources of mankind to the satisfaction of its infinite wants.