420

ON LOCKS AND KEYS.

A very peculiar latch-bolt, which worked from asmall pin motion, the key working through a nicheinto the bolt to draw it back.

Detecting levers, which detect by an underliftas well as an overlift. This is effected by av-formed noze-spring catching in notches on theface of the levers.

They also improved the narrow mortise lock, bycutting out a channel in the main-bolt and workingthe latch therein, or vice versa. This is a neat anduseful contrivance, as when the main-bolt is lockedout, it also fastens the latch, making together a verystrong bolt.

We are sorry to record that for want of a cheapmode of securing inventions to the inventors,* thebenefits which ought to have accrued to the Messrs.Walton have been entirely lost, for no sooner hadthey brought out a new lock, or introduced an im-provement into others, than the same articles weremade by other makers, of lighter materials and in

* Under the old patent law it was only a man of means that could takeout a patent, and under the new law, which came into operation in 1852, apoor inventor is virtually prevented from availing himself of the protectiongranted to his wealthier brethren, as he cannot take out the patent him-self, but must do it through a patent agent. The Government fees for thecompletion of a patent amount to but £25, but few patents are secured(except the inventor takes the necessary steps and draws his specificationhimself) for less than .842: and if there should be numerous drawings, itcosts from £50 to £60. These are the charges when there is no oppositionto the granting of the patent, and the amount secures it for the first threeyears only. We hope for the sake of ingenious but poor inventors the dayis not far distant when a patent may be secured for a quarter of the aboveamount. We consider it would be an act of policy on the part of theLegislature to enact a law accordingly.