doors in Norway, and was first brought to notice by Professor O. RYGH, of Christiania. The key, which is of the same form as the last, enters the slit in the same manner, and after receiving the quarter turn is pressed home into the holes on the inside surface of the bolt like the last. In so doing, when firmly pulled back, it presses down a straight flat steel spring, the fixed end of which is attached to the door between it and the bolt, and the free end of which, when released, catches in a notch in the bolt so as to keep it securely in its place when shut. When the free end of this spring is pressed down by the returns of the key, it clears the edges of the notch, and the bolt can then be drawn back by pressing the key sideways. Both these specimens are therefore key-drawn as in Class B. Assuming this modern Norwegian lock to be a survival of an ancient form, one might naturally expect that the wooden portions of the ancient locks would have perished. The springs, which are the only metallic portions of this lock, would certainly become detached from the wood; their uses, when discovered separately, would not be recognised, and nothing to identify the mechanism with a door fastening would remain but the iron keys. [20] 'La Ferronnerie,' tome ii., p. 229. We must therefore judge of the distribution of this class of lock by the localities in which keys of this form are found. They are of two kinds, one T-shaped as in the preceding examples, and the other, serving the same purpose, but having the two teeth on one side of the shank; both are found together mainly in northern countries, which have been subject to Scandinavian influence. Notwithstanding which, however, the evidence is insufficient to establish the fact of their being of Scandinavian origin. They appear certainly to have been used in Roman times in England and elsewhere, and the influence of southern civilization upon the Scandinavian arts of the iron age is well established. It is always necessary to be on one's guard against inferring that forms originated of necessity in the regions in which they are most widely distributed, for, as we have seen, and have reason to believe, the wooden Scotch lock was carried to the West Indies and used by negroes on account of the facility with which it was constructed and the materials of which it was composed, so in all ages the more simple forms of contrivances must have found acceptance and survived longer on the outskirts of civilization than in those countries in which they were quickly superseded by new improvements.