Serrure de Tabernacle is still preserved. On the escutcheon surrounding the key-hole are figures of our Saviour on one side and two angels on the other—angels of mercy doubtless meant, posted at the portal of the blest to salute the incoming saint receiving the welcome, "Well done, good and faithful servant; enter into the joy of thy Lord." The work of a life apparently was devoted to the elaborate and delicate engraving of images, symbols, and scrolls, and inworking of beads around the edges.
As we come down to the utilitarian centuries, locks and keys began to be made more for practical use than fanciful ornament. The Chinese, as in many other departments of mechanical skill, seem to have led the way in the manufacture of unpickable locks. They introduced the lever, or tumbler principle. The Dutch get the credit of the combination or letter-lock: It was so constructed that the letters of the alphabet, which are engraved on four revolving rings, may be required, by pre-arrangement, to spell a certain word, or number of words, before it can be opened. One of these locks was made to open only with A. M. E. N. The poet Carew, in verses written in 1620, thus describes this complex contrivance:
"As doth a lock
That goes with letters, for till every one be known.
The lock's as fast as if you had found none."
