(In). Methodical and orderly. More generally “Shipshape and Bristol fashion.”
“In the great mass meeting, October 18th, 1884, a route of above three miles was observed in one unbroken line. No cheering disturbed the stately solemnity; no one ran to give any direction; no noise of any kind was heard, but on, in one unbroken line, steady and stately, marched the throngi n `Bristol fashion.' ” —Daily News, October 20th, 1884.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894