In 1858 British railways found a unique way to save time: Rather than stopping at an intermediate station, an express train would simply uncouple a car full of passengers, which would roll into the station under its own momentum, slowed by a guard using brakes. At the station the passengers could disembark, or their coach might be connected to a train that served a branch line. Eventually a local train would deliver the coach to a station where it might be connected again to the express.
This practice continued until 1960 — the last “slip” is documented above.
(Via MetaFilter.)