On the other end of the scale, U-Boats had a free-piston engine
that was the emergency air compressor; if you ran it long enough
you could build up air to restart one of the two Diesels.

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A host is a host from coast to
& no one will talk to a host that's close..........................
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433