112 ON THE SUITABILITY OF CURRENT DESIGN OF SUBMARINES 
whose meshes are of a size suitable for catching submarines, while the counter- 
attack is made by thousands of swift patrol boats whose business is to destroy the sub- 
marine or force him down again whenever he comes to the surface for information 
or for air to start his engines and to recharge his batteries. 
The success of these measures against submarines is undeniable. At the be- 
ginning of the war German good fortune with submarines promised the most im- 
portant results, but as the war drew on the efficacy of submarine warfare dimin- 
ished as methods of reply to it developed. It is now an important arm, but not the 
supreme one. By a line of a priori reasoning the general broad conclusion to be 
drawn from this survey is that the submarine is essentially a defensive arm, whose 
use as an offensive arm, although practicable, yet partakes somewhat of the nature 
of a tour de force. 
After this brief review of the general qualities of submarines and the proba- 
bilities open to them we are ready to take up the consideration of the particular 
types of submarines best suited for American use. Preliminary to this examina- 
tion it will be desirable to summarize the accomplishments of the submarine 
under the conditions imposed by the relative situations of the present belligerents. 
The early performances of German submarines caused them to stand very 
high in popular estimation, but they have not yet been able wholly to justify the 
expectations they first aroused. The efforts of Germany to wrest the control of 
the sea from the grasp of Great Britain and her allies called for the exertion of 
the highest type of offensive war; but, as we have already seen, the submarine, in its 
essential nature, is the defensive weapon of the weak. It met with a temporary suc- 
cess, first in the North Sea and later in the Mediterranean, which in each case 
lasted only until the entente allies had time to prepare counter measures. At the open- 
ing of the war British ships advanced boldly to the German side of the North Sea 
and maneuvered there at slow speeds. The hostile submarines took advantage of 
their opportunity and the British forces withdrew from the vicinity of the German 
coast. Great Britain then developed the net defense of her ports and of the cross- 
channel routes to France, as well as the counter-attack against hostile submarines 
and mine-layers, by the patrol flotillas of whose work such an excellent idea is given 
in Kipling’s “Fringes of the Fleet.” After six months of warfare, the Germans 
began their submarine attack upon commerce. The strategic features of this phase 
of the war need our consideration. 
German submarines were charged with the aggressive task.of destroying com- 
merce, but owing to their essentially defensive nature they were obliged to lie in 
wait in positions where shipping would come to them. The favorite area was that 
between the south of Ireland and the western entrance of the English Channel, since 
nearly all British foreign commerce naturally took that way. But as the Straits of 
Dover were protected by nettings the Germans were obliged to pass around the 
north of Scotland to reach their station, a distance of about 1,200 miles. Once 
there, it was necessary to lie on station some days in order that the time at work 
might be in reasonable proportion to the time needed to make the trip and return. 
