Pimm's No.1 Cup 

Pimm's was first produced in 1823 by James Pimm, a farmer's son from Kent who became the owner of an oyster bar in the City of London, near the Bank of England. Pimm offered the tonic (a gin-based drink containing quinine and a secret mixture of herbs) as an aid to digestion, serving it in a small tankard known as a "No. 1 Cup", hence its subsequent name. Pimm's began large-scale production in 1851 to keep up with sales to other bars. The distillery began selling it commercially in 1859 using hawkers on bicycles.

-From the producer