4 ON THE MAXIMUM DIMENSIONS OF SHIPS. 
speed has taken place. In France the largest submarines of 1901 were about 
135 feet long, 200 tons, and 12 to 13 knots speed; vessels now building are 
240 feet long, of 1,000 tons displacement when submerged, and the estimated 
surface speed is 18 to 20 knots. . 
The same general law has been at work in the mercantile marine. For 
each class the average size of ship has been increased, and the fact is apparent 
in every statistical ‘Return’ of the movements of shipping. In 1860 the 
average gross tonnage of ships (exceeding 100 tons) on the Register of British 
Shipping was 340 tons; in 1870, 580 tons; in 1880, 1,250 tons; in 1890, 
1,570 tons; in 1902, 2,200 tons. Since the Suez Canal was opened the 
average size of the vessels passing through it has grown steadily; the same 
may be said of the vessels passing through the Sault Ste. Marie Canal. 
Every “Return” of ships entering and leaving the great ports of the world 
tells the same tale of growth in dimensions and tonnage. Each annual 
statement of shipbuilding throughout the world furnishes an illustration of 
the working of this law. Many small ships continue to be built but there 
is an universal upward tendency in size. 
II. It must be noted, however, that—notwithstanding the remarkable 
developments of the last ten years—the number of ships of extremely large 
dimensions is relatively few. ‘These great ships naturally attract most atten- 
tion; they are admittedly essential to the performance of special services; 
but the carrying trade of the world is mainly done by vessels of moderate 
dimensions. ‘The British mercantile marine in 1910 owned 11,495 steel 
ships of roo tons (gross) and upward. Of these only 328 ships individ- 
ually exceeded 7,000 tons (gross), 107 exceeded 10,000 tons, and 20 exceeded 
15,000 tons. At the same date there were about 5,000 steel ships on the 
British register of from 2,000 to 6,999 tons gross individual tonnage; and 
over 6,000 ships of from 100 to 1,999 tons. ‘This enormous preponderance 
in numbers of ships of moderate dimensions has resulted from the operation 
of purely commercial considerations, which have similarly influenced all 
mercantile marines. Whatever may be the future growth in size of the 
largest ships built for special services, the bulk of the maritime business of 
the world will always be done by ships of relatively moderate dimensions, 
and they will continue to be the largest contributors to the revenues of port 
and harbor authorities. This fact, as will be shown hereafter, may have an 
important influence upon the upper limit of dimensions of merchant ships. 
III. Naval architects will agree that, provided the money is forth- 
coming for building still larger ships, their construction will be possible; and 
that considerably increased dimensions will present no serious difficulty 
even if the materials for shipbuilding already available were not improved 
i 
