The metropolis is supplied with milk to the extent of about 15,000,000 gallons per year, a great portion of which comes by rail, and is supplied to the retail dealers by contract, at an average rate of 1s.10d. per barn gallon (8 qts.): Dairies are situated in different parts, where milk may be had; and it is also purveyed in tin pails by men who twice a day go their rounds, calling at every house on their "walk."

Cruchley's London in 1865 : A Handbook for Strangers, 1865