… Mr. Grierson remarks that on the L.P.T.B. tube stock in general the electro-pneumatic brake is in use, but that the new 1938 stock is fitted with the self-lapping electro-pneumatic brake, which is under the control of an automatic mercury-operated retardation controller when normal service stops are being made.

I heard a ploop, but I couldn't tell where it came from.

Coordinate term: unicorn

You leave your girl around me; if she's bad she's gonna get stuck.