If the attack materializes, repeat volleys and trench mortar discharge and open fire with the machine guns.
A new, and in many respects one of the most effective weapons produced by the war is the trench mortar.
There was always lots of trench mortar fighting here, and we had orders to send over six shells for every one that came across.
Only once did Fritz blow in the entrance with a trench mortar, and then we had to dig ourselves out.
This form of grenade is very heavy, often weighing 200 pounds and is fired from a trench mortar.
We went in during the night when it was fairly quiet, and we took over the gun positions, from a trench mortar crew.
It was while in those trenches that we first started to use the Lewis gun and the Stokes trench mortar.
Fritz trench mortar batteries sending over a series of particularly nastily ranged shells.
He got this for lifting his trench mortar over the parapet when all the detachment were killed.
A trench mortar had got us full in one of our tracks, and the beastly thing broke.