successive observations will probably be taken at intervals of about one minute, the period of time that the periscope is exposed diminishing gradually to ten or twelve seconds.

Periscope Almost Under Water

In the meanwhile the submarine will have closed to about 2,000 yards, and from now on only a few inches of periscope will be exposed, but at more frequent intervals, about every thirty seconds, and the length of time the periscope is shown will decrease to from ten to five seconds.

At about one thousand yards the firing exposure will be made, and this will probably be for about twenty-five seconds in order to assure a well-aimed torpedo.

The above procedure is not absolutesome submarine commanders show more periscope in attacking and others lessbut it may be taken as typical. This means that from the time the submarine can be seen to the time the torpedo is fired about ten minutes elapse, during which there are about fifteen exposures of the periscope for gradually diminishing periods of time, ranging from thirty seconds down to five seconds, except the last exposure for firing, which lasts about twenty-five seconds.

There has been some talk of a German invention designed to enable a submarine to make a successful approach and attack without showing any periscope. It is improbable that any such device is in general use at present.

Tactics Used Against U-Boats Anti-submarine tactics comprise both methods to destroy enemy submarines and methods to evade their attack. Of course, the primary objective is to destroy the enemy ships, but, since it is easier for the larger vessels, transports, and merchantmen to evade the attack, every effort should be made by the transports and merchantmen to develop tactics of evasion while the fighting navy is developing tactics to destroy. Cordial understanding and co-operation, therefore, between the fighting navy and the merchant navy are of first impor

tance in the successful development and practice of anti-submarine tactics.

The means within the ship of frustrating submarine attack are the lookout, the manoeuvre, and the gun.

An efficient lookout system is essential. A ship can usually avoid attack if the submarine or even the torpedo is sighted when still far enough away to permit a change of course before the torpedo can travel the intervening distance. Safety depends upon seeing," and an alert lookout by gaining 200 or 300 yards in sighting a periscope may avert destruction. The need for a system of intensively trained and organized lookouts is too often neglected.

Zigzag tactics make attack difficult. Also a quick manoeuvre the instant a periscope or torpedo is sighted will often save the ship. Alert seamanship is, therefore, a main reliance of capital ships in avoiding submarine attack.

The gun is chiefly useful to compel a submarine to keep submerged. The presence of the gun is important to embarrass the attack; but to hit a periscope is difficult, and even if a lucky hit is scored no serious damage is done, as spare periscopes are carried by all Uboats.

Skilled Work of Destroyers

Tactics aiming to destroy the submarine can be best used by the destroyers and other small craft specially equipped for this work. Nets and other devices which have proved useful against the smaller type of submarine in comparatively restricted areas are not effective against the larger seagoing U-boats. Under-water weapons such as bombs and plunging shell are needed to attack an under-water enemy.

Plunging shell are somewhat similar in their operation to bombs. It may be supposed that such shell kept falling just short of a periscope by a well directed gunfire and fused to burst both on contact and at a certain depth make it very uncomfortable for an attacking subma

rine.

The seagoing destroyer appears to be the best type of anti-submarine craft so far developed. It combines abilities to scout, to escort, and to destroy.

Seagoing craft of all descriptions approaching the characteristics of the destroyers and capable of carrying guns and bombs are useful. Yachts, fast tugs, and other comparatively small vessels capable of keeping the sea and making reasonable speed can all do good work in the war zone.

Torpedo boats and the smaller submarine chasers and patrol boats, though not so useful as more seaworthy vessels, are still of value for operating nearer the shore. Mine sweepers also are needed.

Seaplanes, dirigibles, (Blimps,) and kite balloons make good scouts because of the large areas they can cover. Weather conditions are seldom such that submarines entirely submerged can be seen by aircraft, but this does not make the latter less valuable for detecting periscopes and submarines awash or on the surface. Also air craft mark the spot where a periscope is sighted and so assist destroyers and patrols in the effective use of their bombs.

Cruisers and converted cruisers are needed for distant convoy work, to carry seaplanes, to carry kite balloons, and also for various administrative and mothership duties.

An anti-submarine force, therefore, includes cruisers, converted cruisers, destroyers, submarines, torpedo boats, patrol craft, mine sweepers, sea planes, dirigibles, and kite balloons, all supplied in as large numbers as can be obtained.

Submarines Now More Wary

As has already been remarked, the details of new equipment and new methods employed in anti-submarine tactics cannot be made public. It is better to let the U-boats find these out at their own cost. But as they learn of the increasing number and variety of schemes used to destroy them they realize that the chances against them have increased. This in itself is a restraint, which makes the U-boats more wary and consequently less effective. At best there is not much comfort or security in a long submarine cruise. The prospect of dying like a rat

in a trap is not pleasant, whether because of accident, or shipwreck, or hostile attack. The strain of constant guard against the devices of an alert enemy must tell on even the strongest nerves. Any method or. contrivance which increases the anxieties and difficulties of the U-boats is thus helpful in checking their activities, and may contribute in unexpected ways to their destruction.

The nature of the U-boat makes trickery conspicuous in German submarine tactics, and, it is fitting that countertricks should prove effective against them. But, as plunging shell, bombs, and other suitable weapons are developed, it is probable that the allied navies will find simple and direct anti-submarine tactics best. History has shown that in the majority of naval campaigns direct methods usually triumph over those which rely upon deceit. It is not unreasonable to suppose that merchantmen of the near future may be so equipped as to make them auxiliary naval submarine hunters; and as tactics to destroy supplant tactics to evade, trade routes will gradually be cleared of this, literally speaking, snake of the sea.

The submarine menace is very real, and people are beginning to appreciate the facts and figures which show it to be the all-important problem of the war. But the United States Navy, if squarely ranged against this menace, will answer it. Anti-submarine tactics are being developed right along, and, while the U-boat as a lawless commerce destroyer was unforeseen and countermeasures consequently not prepared during previous years of peace, still to assume that it will not be successfully met is unjust to the navy, which is upholding traditions handed down from John Paul Jones, from Decatur, and from Farragut. It is safe to conjecture that as soon as Uncle Sam's seamen get fairly started on the work in hard they will prove more than a match for this Ger man underwater navy which hides and strikes and runs away.

A

NEW and significant chapter of war history has recently been written by the organized sailors

of the belligerent countries, in the form of a report prepared by the German Seamen's Union with a view to justifying the U-boat warfare; and of an equally formal and much more scathing answer by the British seamen, who have suffered from that warfare. At the same time an international conference of merchant seamen met at London and voted for the withdrawal of all the sailors' unions of allied and neutral countries from the international union hitherto controlled by a Central Council in Germany.

The International Transport Workers' Federation has its Central Council in Berlin. Under date of March 8, 1917, this council sent a "German Report Upon the U-boat Warfare," along with a circular letter to the seamen's unions of neutral lands. The letter said in part:

The consequences of the German U-boat warfare for the neutral States, and particularly for their seafaring population, stand forth particularly prominently, and therefore all the more conspicuously. In consequence of impulses reaching the I. T. U.'s Central Council, either by direct or by indirect route, from America, England, and other lands, we regard it as necessary and as a duty to seek to describe the situation which the U-boat warfare has created above all for the seamen of the neutral lands. For this purpose we have encouraged the officers of the German Seamen's organization to give an objective account of the causes and the aims of the German U-boat warfare. This is now to hand.

The German Seamen's Report Following is the full text of the report referred to above:

The question of the blame for the world war we will here leave on one side. This question would lead to a conscious taking of sides, which we desire to avoid in this context.

The causes of the war lie, according to the German view, mainly in the sphere of economics, and thereby both the intensity of this world war and its form as a war of economics and of trade are conditioned. It is also, moreover, these

economic causes of the war which have placed the war by sea in the foreground before all other events of the war.

At the commencement of the war Germany and the neutrals pinned their hopes upon the respecting by all parties of international and maritime rights as fixed at The Hague Convention and by the Declarations of Paris and London. If these had been correctly observed in the sea warfare, the seamen of all States would have seen their interests kept in view to such extent as was necessary.

England preferred to take up a one-sided standpoint which regarded only its own interests. It either interpreted all the rules for the sea war to its own advantage in a one-sided way, limited them in arbitrary fashion, or else discarded them altogether. It was nothing else than arbitrariness on the part of England when it subsequently tried to replace the international rights of sea warfare that they themselves had discarded by rules that served only their own interests.

England's bad example was followed by its allies. Their motto at the present day is: "No consideration for the German people, arbitrariness toward the neutrals, and egoism in the achievement of their own interests and aims."

The freedom of the seas was destroyed, Germany and its allies were cut off from contact with the world, and the possibilities of neutral navigation were greatly limited. England certainly had no unqualified command of the sea, but nevertheless did violence to international navigation. And protests from the neutral States, whether sharp or mild, were simply ignored by England and France whenever they found it good to do so. Every new German or neutral protest only stirred England to new arbitrary acts and to an intensification of its terrorizing measures.

The Reprisal Excuse

In this way Germany not only obtained the theoretic right, but was also practically compelled and obliged to adopt reprisals-i. e., to take preventive measures for its self-defense. Germany's intensification of the war by sea was caused by the aforesaid English actions.

When Germany, in face of this situation, resorted to U-boat warfare, this was because that was the most dangerous weapon that could be employed against England. From the technical point of view it was a novelty, behind which lay no practical experiences, and which, therefore, stood outside all international rul