I worked as a Saturday student at Marlows in the '60s having transferred here from George Street, Luton. (In those days even students could request transfers!).
I vividly remember being asked to clean the front door bronze surrounds and so I diligently got some of the paste that the Perspex screens were cleaned with and started polishing.
Unbeknown to me this paste was abrasive and I managed to remove the lacquer protecting the bronze and caused the branch to have the surrounds repaired at considerable expense.
I also remember the vertical carousel connecting the upper warehouse with the buffer room and how many times the metal trays full of breakables e.g. preserves, would cascade down after it jammed!