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The Bramah Lock Controversy.—The Messrs. Bramah have just published in a pamphlet, for general circulation, the articles which appeared in The Morning Chronicle of the 8th and 10th of September, together with the remarks which appeared in one of our contemporaries on the subject. To these remarks they have added the following information:—

“The property of transposition and property of motion which the Bramah lock possesses are illustrated by the sub-joined table. Their first column shows the number of sliders in each lock; the second, the number of transpositions; the third, the variations which may be made in any lock, supposing each slider, to admit only of six notches, by which the actual sum of security compared with unity is demonstrated for any given number of sliders from four to eighteen.

TABLE OF PERMUTATIONS OF THE BRAMAH LOCK.

1.2.3.

424576 51203000 672025920 75040211680 8403201935360 936288019595520 103628800217728000 11399168002634508800 1247900160034488115200 136227020800485707622400 14871782912007322976460800 15130767436800011769693120000 16209227898880002008587829248000 1735568742809600036280117665792000 186402373705728000678651612807168000

“To illustrate the practical effect of these changes or permutations, it may be stated, that when a key to any Bramah lock is lost or stolen, the change of position of one of the sliders will effectually exclude the original key. A new key (and this is the only expense) becomes necessary, while the old one remains utterly useless in whatever hands it may happen to fall.

“This trial having been disposed of, it is intended to fit up the same lock with such improvements as Bramah and Co. now use, and to restore it with its challenge to the place of honour it has occupied in their window, 124, Piccadilly, for half a century.

“The lock on which Mr. Hobbs operated for 16 days before he could open it, was by no means a arge [large] lock being only 4 in. wide, and 1¼ in. thick, and 2¾ in. over the boss, (all outside measurement) while its actual machinery was contained in a barrel 2¼ in. long, and 1½ in. in diameter. In order to open it the operator had recourse (although the spring was only 13lbs.) to a fixed apparatus, to keep it down screwed to the woodwork in which the lock was enclosed, a powerful reflector, a trunk of tools, and four or five other instruments made for the purpose, and this after he had been allowed six or seven weeks before he commenced his operations, to take a wax impression of the of the key hole; und further, the lock did not contain Messrs. Bramah and Co's. more recent improvements in at least three particulars, and its interior had not been opened for 34 years.”