IQI5] SUBMARINE BOATS 137 
the bottom in damaged condition. Shackles are fitted on the top of 
the boats for this purpose 
Special vessels are constructed also for the transportation of sub- 
marine boats. 
SIZE. 
From the moment that submarine boats were taken into practical 
service, claims to increased seagoing capability, speed, radius of action, 
and better living conditions on board were advanced by the naval 
officers. These claims could be best met by an increase in size and we 
can understand, therefore, that size has steadily increased ever since 
the beginning of the century. Boats were then less than too ts. fully 
submerged and are now being built of about 1200 ts. displacement. The 
reason why the displacement has not increased much faster is chiefly 
the difficulty of providing motors for propulsion of sufficient power. 
By an increase in size, moreover, the boats become more difficult to 
handle under water, especially where the depth is small, but probably 
this difficulty would be of secondary importance for ocean-going boats, 
should such boats become a reality. The high cost of large boats will 
put an early limit to their number, the price per ton being almost three 
times as high as for battleships. 
MILITARY VALUE. 
The great military value of submarine boats has been demonstrated 
in the present war. At the present stage of development submarine 
boats afford not only the best means of defence of our own harbors and 
coasts, but may be used also for offensive purposes in the open sea and 
on the coasts of an enemy up to a distance of some five hundred 
miles from their base. The large boats of about 1200 ts. displacement 
now under construction probably have a still greater radius of action. 
A peculiarity of the submarine boat is its faculty to carry out an 
attack with relatively small risk once it has gotten into position, in 
which respect it differs radically from the ordinary torpedo boat which 
must always be prepared for great and almost unavoidable sacrifices 
in order to carry out a successful attack. The greatest difficulty with 
a submarine boat is to bring it into position for attack. 
The future development of the submarine boat is likely to be 
steady but slow. In the meantime it is probable that also the means 
of attack and defence possessed by the battleships against submarine 
attack will progress. Evidently, the first point for the battleship is 
to detect the submarine boat. Once detected before it has reached 
within striking range the submarine boat can generally be avoided, 
