• Adytic lock, 176; machine for manufacturing the keys of the, 185; number of changes in the lock, 188; advantages of, 189; discussion on its value, 192.
• Ainger on the Bramah lock, 111.
• Ainger’s lock, 61.
• Alarum lock, 40.
• American locks, 82; Stansbury’s lock, 83; Yale’s lock, 83; Dr. Andrews’s lock, 84; Day and Newell’s locks, 86; their Parautoptic lock, 89; Hobbs’s Protector lock, 99.
• Ancient locks, 8.
• Andrews’s lock, 84; snail wheel lock, 85.
• Appendix, 173.
• Aubin’s lock trophy, 166; locks forming it described, 168.
• Barron’s tumbler lock, 49; Bramah on, 68.
• Bird’s tumbler lock, 52.
• Bramah on Barron’s tumbler lock, 68; on the defects of the tumbler lock, 68; on the defects of the warded lock, 66.
• Bramah lock, 70; cylinder lock, 73; number of changes in the Bramah lock, 81; picked by Mr. Hobbs, 121; report of the arbitrators, 123, 124; a description of the lock picked, 125; letters from Messrs. Bramah questioning the fairness of the trial, 126; method of picking, 110; method employed by Mr. Hobbs, 129; Ainger on the Bramah lock, 110; Farey on the Bramah lock, 113; improvements made since 1851, 131.
• Brown’s letter lock, 23; picked by Mr. Hobbs, 139.
• Bullion vaults of the Bank of France, 206.
• Chatwood’s safes described, 203.
• Chinese locks, 171.
• Chubb on Davies’s lock, 112; on lock picking, 132.
• Chubb’s lock, 53; described, 54, 56; key of, 57; attempt to pick, 58; experiments on, 59; number of changes in the lock, 55; the detector lock picked by Mr. Hobbs, 115; value of the detector questioned, 117; improvements, 121; Mr. Hodge on the Chubb lock, 114; Chubb’s new locks, 147; bank locks, 149.
• Clockwork, application of, to locks, 39.
• Closet-lock, 17.
• Commercial importance of locks, 174; method of picking, 118; double action, 49.
• Two-bolt lock, 17.
• Ward locks, 18.
• Warded locks, 27; action of the key on the wards, 28; insecurity of, 29; warded locks of the last century, 31; insecurity of, illustrated by Mr. Chubb, 34; Bramah on the defects of, 66; Mr. Fenby on, 173.
• Wheel locks, 18.
• Wheel and pinion, application of, to locks, 39.
• Williams’s lock, 62.
• Wolverhampton, account of the state of the lock and key manufacture at, 154.
• Worcester, inventions of the Marquis of, relating to lock-making, 35.
• Yale’s lock, 83; method of picking, 140.
• Yale’s cylinder lock, 152.

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