A TUNNEL ATTACK

Dominion, Volume 9, Issue 2837, 31 July 1916, Page 4

A TUNNEL ATTACK

FIRING A WAR MINE J ' (By "Tunneller," in the "Daily Mail.'v For several days the lunnellers bad been busy.day ami night putting in 'the charge of explosive to blow the mine. It 'was no small undertaking, for the gallery in which it was laid was over a hundred yards' from the shaft or outlet, and only measured about 3ft. high by •Mil!, wide. All the explosive had to lie carried very carefully and placed in position, and the Bodies were working eo very close to us that it was imperative in make no noise or the whole business would be given away. After the explosive a quantity of "stemming," consisting of sandbags well tilled with clay, and rubbish, had to be built up to prevent the force of the explosion following'the line of least resistance and simply expending its force along our own gallery and probably damaging our own lines. ' . This particular mine was so close io the German trenches that you could hear [jtheir rille-bolts click as they unloaded after firing. Moreover, with a view to > blowing a rcady-mado communication trench the mine was so closo to the surface that the concussion from the oxplosion of even Hie lighter shells from ■ oiir guns falling short and anywhere near us put all the caudles out. One of tho greatest difficulties connected with these operations is to ventilate the galleries and avoid the noise, made by mechanical ventilators or fans, and, as the "stemming" has to be passed from hand to hand to ensure quiet, 'the number of men necessary in a gallery a hundred yards long is so considerable that tho air is rarely good enough to allow a. candle to burn. In this instance we were also without electric lamps, and the work had to be done almost entirely in the' dark —at auy rate, during the last twenty-four hours.

A Second of Margin. The infantry attack was timed to begin at -i.liO. a.m., and the mines-had to be exploded at.4.29 a.m., so that the infantry might rush forward under cover of the smoke from the explosion. In these circumstances it was very important to have our watches set to the exact time of the Brigade Headquarters so that there.would be no confusion, and that our infantry might not start too. early aud be blown up by our own mine?. The strain of the last fen; minutes wait ing Hot the exact moment to come waa very trying.' The seconds seemed to pass like hours. However, we had had. just "one difficulty on.top of another" to'contend with, : and it was 4.25 a.m. before wq were actually ready to fire. So that we had only four minutes to spare.' At this time it was simply raining shells and trench mortars all around,' and in the darkness before, dawn the vivid flashes of our own guns, as well as those of the bursting German shells, blazed out, even though the air was thick was the fumea and reek of tho explosives. Still, our men, who had put in such strenuous, work for to many hours, were glad when the/ were icady to get away, and left the front line to go down the communication trench with as little concern as ever they did,' despite the fact that these communication trenches and the second aud reserve lines are always constantly bombarded during an.attack to try to prevent reserves coming up to the front line, i'ortunately they all got out without a scratch, but they dropped a quantity of their, "tackle"—hammers, saws, airpipes, shovels, and the like—iij their hurry, as I 'discovered when.l left after firing the mines.

In order td blow up this mine to form a ready-mado communication trench the charges had to bo laid in a series, equidistant and of eq.ua! amount, except for ihoso nearest our own end, which for safety's sako wero made lighter. These charges were connected up electrically "in series'' and "in parallel,'" so that there could be no possible doubt of their exploding as soon us the "exploder" or battery was used. To make doubly sure a fuse had been attached,- so that if the electrical connections failed tlio safety tuse would be employed. The of the latter method in a I case like this is that'the rate.of "the. firo travelling along the safety fuse is one foot iu 30 seconds. As our nearest ohargo to tho shaft was some forty feet oft', it would have been, necessary to leave a length, sufficient for a minuto or two on the fuso to allow the man who lit it ■> got out, and,'as I havo. pointed out, w wore tied down ttra niiuute.

- Of course it could liavo been aono with instantaneous /fuse, but it would have required all tho length to the shaft top ironi each separate charge, and as the tunnel was exceedingly wet this would not have been practicable. As.it was, .we had twelve "leads" or cables coming out of tho shaft top which were all marked and numbered so as to prevent a .mistake, and all brought to a point* behind a thickish part of the parapet, where wu "rigged up" a few stout poles and props as a covering at any rate against splinters. Here we crouched and waited the time when our watches (we had three all put by "brigade" ■time) should come round to 4.29 a.m. Pressing the Button, The time came at last, and we pushed down the handles of the exploders.. So great was the concussion of the shells dropping at the time that I thought the charge had failed, though such a charge or series of charges as we were firing was sufficient to 6hake down dug-outs several hundred yards away. To make sure we hurriedly changed the connections on the batteries, using three exploders for each separate charge, and then when our minute's grace was almost up we gave up troubling further and came out from our improvised shelter feeling that wo had failed. How pleased we were to meet a cheery captain as we went along the front line towards the communication trench, who told us the mine had exploded splendidly !"■ The captain was now in the same state of excitement awaiting his time to lead his men over the parapet and across to the German lines as we had.been wait-' ing for 4.29 a.m. He was the captain of the second line, who were now manning the front-lino trench, while the front-lino fellows were already in No Man's Land lying hidden in a ditch. At Inst the moment, arrived, and the order to charge forward was given, and away they rushed across the open, and in less than half an hour had taken the first three lines of German trenches. The sappers, 100, had rushed out, and with pick and shovel were busy making the connection blown by our mine into a communication trench by which ammunition and reserves could be brought forward to the' lads in front. This work brought to light the fact that wo had blown in a German gallery within four feet of our own and had killed at least four Germans by the explosion—how many more there might have been in their demolished gallery one could net say.