The National Museum of Computing (on the Bletchley Park campus) continue to make progress on the rebuild of the EDSAC. This video shows the technology of the delay lines they are building - rather than sound waves in mercury, for safety reasons they are using torsion waves in nickel wire, as became conventional not long after EDSAC:
I’ve cued up to the final bit, where the initial orders for the machine are loaded from a bank of hard-wired uniselectors and the code is displayed in real time on the console traces.
There’s also a link to a related article which mention’s Turing’s famous suggestion to use gin instead of mercury: