c. 1869-75 original and completely intact ornamental cast brass interior residential window sash lock manufactured by the p. & f. corbin co., new britain, ct. window sash locks are generally described as a contrivance which, by fastening the top rail of the lower sash to the bottom rail of the upper sash, prevent the opening of windows from the outside, either by lowering the upper or raising the lower sash. their general construction and operation is as follows: a lever is pivoted upon the top rail of the lower sash. when the lock is open the directin of this lever is the same as the rail of the sash. to fasten the sashes it is necessary to turn this lever on its pivot to a position across and at right angles to the division line between the impinging rails of the two sashes, when it engages with a catch on the bottom rail of the upper sash. this catch, if, as has generally been the case, it consists of a simple hook, under the projection of which one end of the lever remains when in the locking position, is sufficient to prevent the opening of the window by any direct pressure on the sashes exerted in the ordinary way to open a window, but there would be nothing to prevent the pushing aside of the locking lever by inserting from the outside, between the impinging rails of the sashes, a knife-blade, paper-cutter, or other similar instrument, and thus opening the lock. to prevent this, various devices have been used to hold the locking lever fast when in the locking position, so that it could not be moved sideways from the outside, but only from the inside, by disengaging it from the catch in the ordinary process of unlocking. the ornamented sash lock with tapered steeple finials contains a functional pivoting arm that sweeps against the slightly curved slot found on the keeper. patent date lightly embossed on the underside of the keeper. excellent working condition. likely salvaged from a stately mansion.