Throughout this entire district the Russians built a dense network of trenches, and it was especially by means of these that the Germans were repulsed not only successfully but with great losses to their attacking forces. The more important of these earth fortifications were built in a novel fashion. The main part of each had the form of a crescent with its horns turned toward the enemy. Every attack from the latter, in order to find a point big enough for an effective attack, had to be frontal in nature; that means, it had to be directed against the main part of the crescent-shaped trench. But, whenever such a frontal attack would be executed and just as soon as the attackers would be inside of the sides of the crescent, machine guns and rifle fire from its two horns would hit them on both flanks and frequently destroy them utterly. In order to make the Germans advance far enough into the crescent, advanced trenches had been built in front of its horns, which were connected with the main part of the crescent by communicating trenches.
These advanced trenches were manned by comparatively small forces, whose duty it was to offer a sufficiently strong resistance to draw a fairly good-sized number of Germans. This purpose having been accomplished the troops in the advanced trenches would give way and retire by means of the communicating trenches into their main positions. Again and again the Germans followed them into the death-dealing hollow, to be decimated unmercifully in the manner described above. At the same time Russian guns would open fire and direct a sheet of shells toward the back of the attacker, thus cutting off most effectively any reenforcements which might have made it possible for the Germans to either storm the main trench or withdraw at least that part of their attacking party which had not yet fallen prey to Russian ingenuity. It is said that General Russky contrived to throw out fortifications of this nature around Dvinsk in an immense circle which had a diameter of twenty miles and with its circumference formed a front of almost two hundred miles. Of course, this front was not in the form of an unbroken line. There were any number of places along it that could be occupied by the Germans practically at will. But once there the next advance would invariably bring them face to face with a new obstacle, kill hundreds of them, and frequently result in the withdrawal of the remnant to its main line, from where another advance would be attempted promptly on the next day.
One other feature of these fortifications contributed a great deal to their becoming practically impregnable. The Russian engineering troops saw to it that all these works were built as narrow as possible and were dug as deep as the ground permitted. It was this fact which made the German artillery fire so surprisingly ineffective at this point. In spite of its unceasing fierceness the results it accomplished were as nothing compared with the effort and expense it involved. For, of course, no matter how brilliant the gunnery, how wonderful the cannon, how devastating the shells, if the target at which they are aimed is sufficiently far away and sufficiently small, the result will be disappointing; and the Russians at Dvinsk saw to it that the Germans experienced a long series of costly and heartbreaking disappointments of that nature.
A Hungarian staff correspondent, who was with Von Hindenburg's army, had this to say about the siege of Dvinsk, or rather about the attacks on its outlying fortifications: "The German army could not make use of its heavy artillery, for it proved quite useless, owing to the extreme narrowness of the Russian trenches. In the lake district south of Dvinsk the Russians made the utmost of their natural defenses, and even the advanced trenches there were only occupied after very heavy losses, and then retained under the most trying circumstances. In taking Novo Alexandrovsk—a village about fifteen miles southwest of Dvinsk on the Dvinsk-Kovno post road—the losses incurred on our part were unprecedented in severity."
Another correspondent in writing to his paper, the "Vossische Zeitung," describes the fortifications of Dvinsk as follows: "Every rod of land is covered with permanent trenches, roofed securely against shrapnel and shell fragments and connected with so-called 'fox holes'—small shelters in which the garrisons are safe against the heaviest shells. Sand trenches, skillfully laid out, so that they are mutually outflanking, smother exploding projectiles. The flanking fire of the machine guns often annihilates the assailants when they are apparently successfully attacking. One company alone thus lost fifty-one dead in one day. Between September 15 and October 26, 1915, Dvinsk, in a way, was captured fifteen times, but it is still in Russian hands. The bombardment has reduced the fortress in size one-half without affecting in the least the strength of the remainder."
South of Dvinsk, however, the Germans had been able to advance their line slightly farther to the east. On September 27-28, 1915, and the following days they were fighting on the shores of Lake Drysvidly, about ten miles east of the Dvinsk-Vilna railroad, and at Postavy, ten miles south of the Disna River, a southern tributary of the Dvina. Again on October 1, 1915, the Russians attacked north of Postavy, as well as south on the shores of Lakes Narotch and Vishneff, but without success. Throughout the next day the fighting continued, although not particularly severe. But on October 6, 1915, stronger Russian forces were again thrown against the German lines. In the beginning they gained ground at Koziany, on the Disna, and south on Lakes Drysvidly and Vishneff, but the day's net results left the Germans in possession of their old positions. Russian attacks in that region during October 7-8, 1915, suffered the same fate.
On the latter day the Germans made an attack in force south of Ilukst, ten miles to the northwest of Dvinsk, and took the village of Garbunovka, capturing over 1,000 Russians and some machine guns. On the next day, October 9, 1915, the Russians attempted unsuccessfully to regain these positions and were also defeated to the west of Ilukst, north of the Ponevesh-Dvinsk railroad. On the 10th, attacks west of Dvinsk and Vidzy, north of the Disna, had no better results.
Throughout the following week, October 10 to 17, 1915, the Russian army continuously attacked along the entire line west and south of Dvinsk. In some instances they succeeded in breaking temporarily and for short distances through the German line. But in no case did this lead to a lasting success and, in some instances even, the Germans closed the line again so quickly that the Russian detachments who had broken through were cut off from their main body and fell into the hands of the Germans.
Both on October 22 and 23, 1915, the Russians launched strong attacks near Sadeve, south of Kosiany, which were repulsed in both instances. On the latter day the Germans again attacked northwest of Dvinsk, near Ilukst, and captured some Russian positions as well as over 3,500 men and twelve machine guns, maintaining their hold on the former in the face of strong Russian counterattacks on October 24, 1915. Small German detachments which had advanced toward the north of Ilukst on that day, however, had to give way promptly to superior Russian forces. In spite of this the Germans repeated the experiment on the following day with stronger forces and at that time gained their point. On October 26, 1915, the Germans broke through the Russian line south of the Ponevesh-Dvinsk railroad, between the latter city and the station of Abele, but had to give up part of the newly-gained positions during the night only to regain it again the next morning. A Russian attack against this position undertaken later on that day, October 27, 1915, broke down under German artillery fire, before it had fully developed.
In a similar way the most furious kind of fighting took place throughout this period on the Riga salient. There, too, the Russians, successfully held the Germans at a safe distance. In the second half of October, 1915, when Von Hindenburg apparently had become convinced that he would not succeed in taking Dvinsk before the coming of winter, if at all, the German general began to shift the center of his operations toward the north and massed large forces against Riga. According to some reports as many as six army corps were concentrated at that point. The country there, though different from that in the vicinity of Dvinsk, was hardly less difficult for the Germans and offered almost as many opportunities for natural defenses to the Russians.