Such a programme of work was beyond the unaided power of the Tank Corps, and therefore the 184th Tunnelling Company was allotted to the Corps, one section to each Brigade.
Much of the canal bridging and of the track making was done under fire, shrapnel, gas and H.E.
Often a series of shells, bursting on the newly laid causeway would undo a day’s work in a few minutes. Half the time the men had to wear gas-masks, and almost always they worked knee-deep in liquid mud or in the oozy bed of some little “beke.”
Yet in no instance did the 184th Tunnelling Company fail to carry out the work allotted to it.
One very ingenious piece of mechanism for use on the Tank itself had been evolved at Central Workshops in view of the Flanders mud. This was the “Unditching Beam.” It was a massive baulk of teak, iron shod at the ends, and having heavy chains whereby it might be secured to the tracks when it was needed.
Its length was somewhat greater than the width of the Tank over its tracks, and therefore ordinarily it was carried lengthwise along the back of the machine.
Its battle position was across the Tank, where it rested on the raised guide-rails which served to lift it clear of the conning-tower, the silencer and the other excrescences above the armoured back.
To these guide-rails it was secured by special holdfasts to prevent it from breaking adrift when the Tank pitched or rolled amongst the shell-holes.
When the Tank got “bellied,” these holdfasts had to be released and the drag-chains attached to the tracks by one of the crew climbing out on to the roof—the feat being one of some danger when in the near presence of the enemy.
The beam having been duly attached, the differential gear would be locked and the clutch released, when the revolving tracks would carry the beam over the nose of the Tank, from which it would dangle by its two track-chains until dragged beneath the Tank itself.