(a)The product of half the length of the vessel, measured along the waterline and round the contour of the vessel from the centre of stem to centre of stern post multiplied by the interior greatest breadth of the vessel or by the greatest breadth of the cargo, should this over-hang, or, in the case of the logs, be lashed alongside, multiplied by the greatest interior depth from the water-line to the bottom of the vessel, is to be taken as equal to the number of maunds upon which toll shall be levied.
