In 1854 this rule was changed by the Merchant Shipping Act, which provided that the actual cubic contents of a vessel’s hull should be measured, a registered ton being reckoned as 100 cubic feet. This is known as the Moorsom system, and is still in use and likely to continue. It was adopted by the United States in 1865; Denmark, 1867; Austria, 1871; Germany, France, and Italy, 1873; Spain, 1874; and Sweden, 1875. The old practice of calculating tonnage in the United States was adapted from the English, and the mode of measurement was as follows: The length was measured on deck from the fore part of the stem to the after part of the stern-post; the breadth from outside to outside planking at the broadest part of the vessel; the depth of the hold from the plank on deck to the ceiling of the hold. This last measurement was not used, the depth of a vessel for tonnage purposes being assumed to be one half of her breadth. In order to find the tonnage, three fifths of the breadth were deducted from the length and the remainder multiplied by the breadth, and this product multiplied by one half the breadth, or the assumed depth, the last product was then divided by 95, giving the formula: (L - ⅗ B) × B × ½ B/95 Thus in a vessel measuring 100 ft. x 20 ft. x 18 ft.: Length of vessel 100 Subtract ⅗ breadth 12 ------ Length for measurement 88 Multiply by the breadth 20 ------ 1760 Multiply by half breadth 10 ------ 17,600 Divide 17,600 by 95 and the result is 185 + 12/19 Total tonnage 185 + 12/19 This mode of measurement continued from colonial times until the Moorsom system was adopted in 1865. The dimensions of ten representative American and British clippers were as follows: Length Breadth _Nightingale_ (1851) 178 “ 36 “ American _Oriental_ (1849) 183 ft. 36 ft. _Celestial_ (1850) 158 “ 34 “ 6 in. _Stag-Hound_ (1850) 209 “ 39 “ _Flying Dutchman_ (1852) 187 “ 38 “ 6 in. British _Falcon_ (1859) 191 “ 4 in. 32 “ 2 in. _Taitsing_ (1865) 192 “ 31 “ 5 in. _Titania_ (1866) 200 “ 35 “ _Spindrift_ (1867) 219 “ 4 in. 35 “ 6 in. _Thermopylæ_ (1868) 210 “ 36 “ Although these British ships show less breadth than the American, yet they have more breadth in proportion to length than the earlier British clippers, such as the _Stornoway_ (1850), _Lord of the Isles_ (1855), etc. INDEX Vessels not otherwise designated are American A _Abbot Lawrence_, medium clipper ship, 255, 256, 258 _Abergeldie_, British clipper ship, 205