but by April 10 the effort wore out and the great siege subsided temporarily, al-. though heavy bombardments continued to alternate with infantry charges. By the middle of April French counterattacks grew much more frequent.

If the casualties at Verdun in the two months' fighting are reckoned at 300,000, it will probably be fair to assume that of this total not more than one-third were French. Never in all the history of French military glory has there been a brighter chapter than that written at Verdun. Every poilu in the ranks chanted "You Shall Not Pass," and died gladly to confirm the interdiction. Superficial military critics had long credited the French soldier with brilliant adaptability for attack, but had denied him credit for ability to "stand the gaff" on a long, hard defense. The armies under Maud'huy in Arras, de Castelnau before Nancy, and Pétain at Verdun have forever disproved that slander.

Verdun was a veritable hell in February, March, and April, 1916, but the French held it against artillery and infantry attacks of unparalleled intensity and persistence. An astonishing revelation was the preservation of the élan for attack which suffered no loss of enthusiasm by the long periods of dogged defense. From the gallant eloquence of Driant to his Chasseurs facing death in Caures Wood to the gasping phrase "Passeront-pas" of the humble private giving his life on Le Mort Homme, there seemed never to have been a moment when cheerful sacrifice of life itself could not be relied upon.

The great German armies went down to defeat before a greater foe at Verdun, but, heroic and competent as the French were, there came a time in the Spring when the Germans succeeded in pushing dangerously close to the beleaguered city on the northeast front. They were slowly but steadily crushing in the defenses on this front, and had in May and June taken Fort Vaux, the strongly fortified positions at Thiaumont Farm, Douaumont, and were within three short miles of Verdun. Across the river they had Cumières and Le Mort Homme and were eating their way into Hill 304. Then

the great storm to the north broke as French and British together hurled themselves against the German lines above the Somme. The Germans were compelled to shift all available reserves to that hard-pressed sector through the Summer months, and so the great effort to take Verdun rested. There have been many hard battles on both sides of the river since then, but the French have gradually pushed the invader back from his hard-won positions in the Vaux sector. The most serious of the later German attacks have been in the region of Hill 304, which remains a massive barrier to their progress on the west front. Serbia Overwhelmed

Serbia had been the superficial cause of the worldwide war and for two years was remarkably successful in avoiding any serious castigation. The early Austrian efforts to invade the little Balkan State had been defeated and the menace of mighty Russia on the east had prevented any renewal of Austrian efforts to avenge the murders at Serajevo in June, 1914.

Early in the Autumn of 1915 Bulgaria joined the middle Europe alliance, and thus a dangerous new foe close at hand loomed up on the Serbian horizon. Field Marshal von Mackensen appeared across the Danube opposite Belgrade in command of a new German-Austrian army. A fortnight later French and British divisions were landing at Saloniki. The stage seemed set for a great allied campaign in co-operation with the Serbs to turn back the new invasion from the north and at the same time punish the Bulgars for joining the Teuton cause. The French under Sarrail were the first to land at the Greek port, and they pushed out northward at once to prevent the Bulgars from seizing the Iron Gate, the narrow gorge on the Vardar, 90 miles above the base, the only pass through which rail communication with Northern Serbia could be maintained. By the end of October Sarrail's men were 75 miles up the Vardar above Krivolak and General Mahon's Tenth British Division had come up to Lake Doiran, where they guarded the French right flank from any possible Bulgar attack.

About the middle of September Austrian batteries began to bombard Bel-. grade, but it was not until Oct. 3 that the heavy bombardment with great guns began. A few days later the Teuton armies crossed both the Save and Danube rivers, and on the 8th the Germans were in part of Belgrade; by the morning of the 9th the army of von Kovess had captured all of the capital. Other columns pressed forward across the rivers, and by Oct. 11 the Germans had deployed on a front of 100 miles from Shabatz to Graditza.

As soon as the Germans were safely over the river frontiers, the Bulgars formally declared war-on Oct. 12-and a few days later von Kovess drove the Serbs from the positions south of Belgrade to which they had retreated after the town fell. Raiding Bulgar cavalry cut the railway at Vrania, (Vranja,) and the Serbian town of Egri Palanka was taken by a Bulgarian army. Veles fell on Oct. 20 and Uskub was lost on the 22d. At the latter point the meeting of the river valleys along which the railways run produces a traffic centre which practically controls all the travel routes of Central and Southern Serbia.

The principal Serbian armies in the north were now cut off, a disaster which might have been averted if the Allies from Saloniki had been a little earlier on their job of keeping the Bulgars away from the Vardar Valley.

Serbia's Fate Sealed

On Oct. 26 a column from the army of von Gallwitz crossed the Danube at Orsova and on the same day both Negotin and Prahovo were captured by Bulgarians, who seized large quantities of supplies sent up the river for the Serbs. By the end of the month the Austrians and Bulgars had joined hands and the fate of that part of Serbia which lay

below the Rumanian frontier was sealed. On Oct. 30 the Germans reached Kragujevatz, the Serbian arsenal, and the North Serbian army had been driven back toward Nish. Another force held the hills north of Monastir. Nish fell on Nov. 6, and after a heroic resistance at Katchanik the last of the northern army began a terrible retreat toward Montenegro.

At Babuna Pass, above Prilep, a Serb force of about 5,000 men fought bravely to stem the tide of invasion, but, finding that no help could be expected from the Allies, this heroic remnant finally retreated toward the Albanian frontier.

While the Serbs were struggling to hold the Babuna Pass a strong French column, trying to join hands, got to within ten miles of the pass, but, meeting powerful Bulgar forces, was compelled to abandon the effort and retreat to an intrenched camp at Kavadar. So ended the hope that the Allies would succor the Serbs. The remnants of the armies which had fought to save the fatherland were soon struggling over the wild mountain roads toward the west. By the end of November, 1915, practically all of Serbia was in the hands of the enemy, and early in December the French began to retreat from Serbia into Northern Greece. In the first week of December the Austro-Germans took Monastir and the Bulgarians began to attack the British positions near Lake Doiran. After a not very stubborn defense both French and British armies fell back before the Bulgarians and retreated behind the field fortifications, which had been prepared on an extensive scale outside Saloniki. The Greeks, making some virtue of necessity, handed the seaport over to the Allies, who soon found themselves in a state of siege behind the fortifications along the hills outside the city.

I

F we can believe the spokesmen of the Prussian Government, Germany is depending upon her submarine navy

so to cripple the ocean trade supplying men, food, and munitions to allied armies as to compel the acceptance of peace terms pleasing to the present leader of the German Nation.

Hindenburg has announced that it is only necessary for the German armies to hold their own on land while the Uboats at sea decide the war in Germany's favor.

It is strange that Germany's first soldiers should point out that the submarine, the only naval weapon able to evade the allied blockade, promises a respite and a hope that the German armies cannot give, even though the latter have been successful on all fronts and have conquered entire countries. Thus does Germany acknowledge the principle so well taught by the distinguished American naval officer, Admiral Mahan, that in all great wars between commercial nations land power is ancillary to sea power.

The answer of the United States to this Hindenburg announcement is characteristic and may be phrased somewhat as follows: The American Army will help hammer the Prussian lines while the American Navy defeats the U-boat.

As the war now enters upon its last stage there can be no doubt as to the final result. The end is in sight, and, as in past wars, so in this one, the force of sea power is slowly but surely shaping the issues. As the arteries of sea-borne commerce to the Teutonic Powers are more and more effectually blocked, and as the U-boat terror subsides while new strength and vigor from America, Africa, and Asia are transported more and more

easily to France, England, and Italy— the realization will slowly but surely be forced home that Pan-Germanism has been defeated and that Germany must give up the evil policies she has fought so desperately to defend and propagate.

It was Germany's unscrupulous methods of using her U-boats against commerce that precipitated war with the United States, and now it is the obvious mission of the American Navy to overcome this submarine menace in the Atlantic. As soon as this mission is accomplished and the U-boat campaign is demonstrated a failure, it may be assumed that Germany will stand ready to yield pretensions as a victor.

of

Secrecy is important in the development of certain kinds of anti-submarine tactics. Mention cannot be made new devices, because to forewarn the enemy is to forearm him. But no harm will result from an outline discussion of the older though still effective methods of submarine defense which are now well known to the enemy. On the other hand, a clearer understanding of the question will stimulate interest in the wider development and practice of common-sense methods against the submarine. These may contribute quite much to the ultimate defeat of the Uboat as highly scientific inventions.

as

In order to understand anti-submarine tactics it is necessary to know something of the tactical characteristics of the craft against which these countermeasures are directed. Of course, any very recent developments are not known, but there is no evidence at hand that radical advance has lately been made in U-boat construction.

The cruising radius of the larger sub

marines is about 6,000 miles when steaming on the surface at a slow speed of six to ten knots. The newer boats are reported to have a maximum speed of eighteen knots, but economy of fuel is so important, and the consumption is so much greater for high speeds, that submarines use the economical slower speeds except perhaps for short spurts. It is obvious that submarines operating from distant bases cannot well afford to chase merchantmen unless they happen to be slow ones. Their usual procedure is to lie in wait along the trade routes and attack the ships which run up to them.

Limitations of Submarines

Submarines, after cruising a certain distance while submerged, are compelled to come to the surface to recharge their batteries. Here again the maximum submerged speed of about fourteen knots for the newer boats and about ten knots for the older types is extremely uneconomical. For example, approximately speaking, the average submarine when submerged can go four to five hours at ten knots, a total distance of about forty miles; or ten hours at about seven knots, a total distance of seventy miles; or thirty-six hours at about four knots, a total distance of 144 miles; or seventy-two hours at steerage way, (about two and one-half knots,) a total distance of 180 miles. It also has been rumored that the most recent U-boats can go as far as 250 miles at a stretch without corning to the surface. But when the limit is reached, whatever it may be, the submarine must stop and wait for an opportunity to come to the surface to recharge batteries.

It follows, then, that anti-submarine tactics which force the enemy to go comparatively long distances at high speeds tend to limit their activities. It is reported that when the prospects are such as to promise considerable uneconomical cruising, either on the surface or submerged, submarine commanders usually abandon the attack.

It may be mentioned here that it is extremely hard to control merchantmen and compel them to practice simple antisubmarine tactics-such as steering zig

zag courses-calculated to embarrass the submarine in the accomplishment of its purpose. It is difficult for seamen who for years have navigated the usual lanes to understand and carry out instructions intended to safeguard them from a foe they cannot see. When the tangible proof of the enemy's presence arrives it is too late. Utmost vigilance is necessary at all times, and to get this requires a strict discipline which does not exist on board the majority of trading ships. The percentage of torpedoed ships is not sufficiently high to spur the crews to great exertions.

There are many influences inclining the individuals on board ships passing through the war zone to the opinion that getting safely by is largely a question of luck. There seems to be more or less prevalent a sort of fatalistic attitude toward the submarine, or the gambler's attitude of taking a chance against being torpedoed, with a resulting laxity in the observance of safeguarding measures. Whatever be the cause of this indifference to the practice of simple anti-submarine tactics of evasion, there is plenty of evidence that many a ship has played into the hands of the U-boat either by failure to carry out instructions, or by a poor lookout system, or by neglect to steer zigzag courses before sighting the submarine, or by stupid seamanship after sighting it. This is unfortunate, but not surprising. The nature of the submarine enemy is such that to combat it successfully requires a personnel of a high order of intelligence, well trained and well disciplined.

How Torpedoes Operate

The armament of the U-boats consists of both guns and torpedoes. The hull of the newer types is protected to some extent by armor, but is still so vulnerable that few U-boats will risk a gun engagement with a well-armed enemy. As nearly all ships are now armed, the torpedo has become the principal weapon of attack.

The general characteristics of the torpedo are now pretty well known. It is a highly scientific mechanism consisting of many intricate parts ingeniously assembled in a metal shell about twelve

to twenty feet long, twenty-one inches in diameter, weighing about one ton, and valued in this country at about $6,000. In appearance a torpedo somewhat resembles a small, elongated auto-submarine. It has horizontal and vertical rudders which can be so adjusted, in conjunction with an automatic steering device, as to make the torpedo keep at a certain depth and either travel straight or in a curve. The torpedo is propelled by a screw driven by an automatic compressed air engine, capable of giving a speed as high as thirty-six knots. By the act of launching from the tube a starting lever is tripped, which causes the propelling mechanism to go ahead at full speed. The head of the torpedo carries a powerful bursting charge. The object of submarine tactics is to detonate this high explosive against the underwater body of the target ship.

To accomplish this object the submarine commander has to make preliminary observations through his periscope, estimate the course, speed, and distance of the enemy, manoeuvre his boat to a favorable position, make the necessary firing adjustments, aim the torpedo, and then launch it.

It is obvious that the closer the target the better the chances of scoring a hit. Torpedoes are rarely fired by submarines at greater ranges than one thousand yards because the percentage of hits at longer ranges is comparatively small. Glancing hits, moreover, are not often effective. When the target ship is end on, the torpedo, even when correetly aimed to hit, frequently glances off without exploding, (bow wave and wake currents assist this deflection), or if it does explode fails to do much damage. Torpedoes are so expensive, the supply is so limited, and the U-boats themselves are so precious that every effort is made to avoid risk of failure and destruction.

U-Boat's Method of Attack

It is thus seen that submarine tactics are not altogether simple. If the target ship is fast, steers zigzag courses, keeps a bright lookout, carries guns, and is also attended by escort ships specially

equipped for destroying submarines, the difficulties in the way of successful attack are considerably increased.

The problem facing the U-boat Captain may be summarized as follows:

Keeping in mind the importance of safeguarding his own ship and also the necessity of economizing in both fuel and torpedoes, he first studies the situation and if he is in a favorable position ahead of his quarry, he decides to attack. Assuming that the approaching vessel is armed, he submerges before there is likelihood of discovery. He then observes at more or less frequent intervals through his periscope, takes bearings of the approaching target ship, and estimates her course, distance, and speed. His purpose is to avoid discovery and at the same time to manoeuvre into a favorable position for launching at about one thousand yards' range a torpedo so aimed and adjusted as to strike the enemy ship at an angle of incidence to her fore and aft line greater than thirty degrees.

Critical Moment of Attack

There are, of course, any number of variations in the methods of making a submarine attack, but as an illustration, suppose a U-boat submerged and approaching from a bow bearing at a speed of six knots toward a target ship advancing at twelve knots. With fairly good glasses a periscope can be distinguished with reasonable certainty in comparatively smooth water by an alert lookout at 3,000 to 4,000 yards.

As the ship can probably escape by manoeuvring if the periscope is seen before the torpedo is fired, it follows that the critical time for both the attacker and the attacked is during the interval of approach from the range of 4,000 yards to the firing range of about 1,000 yards. This interval will last approximately from seven to ten minutes, depending upon the angle of approach and upon how accurately the submarine judges the course of the target ship. Beginning at 4,000 yards the submarine can be expected to show about one foot of periscope and observe for a period of about thirty seconds. After this four or five