also mounted, on the wall
(just under the clock) outside the gate to the Royal Greenwich
Observatory, is a “Gauge” where the “public” can measure the
Imperial Standard Length. The stated length of an “Imperial”
British Yard, two Feet, one Foot, six Inches and 3 Inches is
the distance between the inner faces of the 2 “D” shaped studs.

C U on the email, keith 