"Tapping The Admiral" is slang for drinking
on the QT. The
origin story: When Admiral
Lord Nelson was killed at
Trafalgar, his body was
preserved in a
cask of
rum for the voyage home -- a primitive but perfectly servicable
embalmment.
Upon return to port, it was discovered that the keg was empty save for the body, for the sailors had surreptitiously drained the grog off, measure by measure.