E. Cobham Brewer 1810–1897. Dictionary of Phrase and Fable. 1898.
Jack of Newbury.
John Winchcomb, the greatest clothier of the world, in the reign of Henry VIII. He kept 100 looms in his own house at Newbury, and equipped at his own expense 100 of his men to aid the king against the Scotch in Flodden Field.
