Source: The Illustrated London News, Feb 21, 1846, p.135
CHUBB'S LOCKS, Fire-proof Safes, and Cash Boxes.—Chubb's New Patent Detector Locks give perfect security from false keys and picklocks, and also give immediate notice of any attempt to open them. Chubb's Patent Fire-proof Safes, Bookcases, Chests, &c.; strong Japan Cash Boxes and Deed Boxes of all sizes, fitted with the Detector Locks—C. CHUBB and Son, 57, St. Paul's Churchyard.