A fuse plug spillway is a low embankment designed to be over topped and washed away in the event of a large flood.
From the en.wikipedia.org
Showing the rear of the plug with its 2 A fuse.
From the en.wikipedia.org
Wouldn't it be great to see at a glance whether a fuse in a plug has blown without needing to test it?
From the newscientist.com
If there is a fuse holder on the bottom of the plug, gently open it using the tip of a slot-head screwdriver.
From the guardian.co.uk
Operators frequently did not check simple faults, for example checking whether a fuse had blown or a power plug had become disconnected.
From the en.wikipedia.org
In soggy Coney Island, Evangeline Pugh said her apartment on the second floor of a public housing high-rise lost power after a fuse blew when she tried to plug in a heater.
From the suntimes.com
The plugs were available in both 5 and 13 A versions, differing only by the widths of the live and neutral pins, and contained an internal fuse of the same rating as the plug.
From the en.wikipedia.org
A fuse that worked loose could end up protruding from the socket, electrically live and posing a shock hazard, when the plug was removed.