Loki...
I think it was Tom who introduced me to the tunnel that ran under the central area, between Queen's Building and the Tower (elsewhere too, I believe). Apart from other uses, it served as a conduit for the Lamson Tube system; one could hear the containers hurtling along in the pipes. It was a somewhat eerie way to get into the tower building.
I only have a vague recollection of the existence of the tunnel but I do have clear memories of the two bods who were i/c the Lamson Tube system.
They were known as Tweedle Dum and Tweedle Dee and hated one another like poison.