Plate II

Figs. 18A to 22A. Old Scottish treble wooden tumbler lock (Patent Museum).

Figs. 23A to 25A. Wooden tumbler lock from Norway (Hazilius Museum, Stockholm).

Figs. 26A to 28A. Wooden tumbler lock made by negroes of Jamaica (Museum, Kew Gardens).

Figs. 29A to 31A. Wooden tumbler lock from British Guiana (Christy Collection).

Fig. 9B. Probable use of fig. 29B, Plate III., as a key for a single tumbler lock.

Figs. 10B to 12B. Modern Egyptian wooden tumbler or pin-lock in use at the present time.

Fig. 10B. Longitudinal section showing pegs raised by key A preparatory to withdrawing the bolt B.