93. Elevator Latches.—Locks or latches for use on doors of elevator shafts are usually operated by a key from the outside and by a flush lever handle from the inside. The latch illustrated in [Fig. 132] consists of a pivoted arm with a hook at its end to engage with a strike on the jamb. This type of latch is the one generally employed.
Fig. 133
94. Secret Gate Latch.—In [Fig. 133] is shown a secret gate latch, which is used for office gates. Latches of this kind may be had in either the rim or the mortise type. They usually consist of a spring bolt that cannot be operated except by a concealed button or similar device. In the type of latch shown in the figure, the concealed button that controls the latch is located on the lower edge. The knob shown is fixed and does not operate the latch.
95. Ornamental Nails and Studs.—Although the constructive necessity for ornamental studs and nail heads has disappeared under modern methods of wooden construction, they are still used for purposes of decoration, and a great variety may be had. Several stock designs are illustrated in [Fig. 134]. These nails and studs are made of various metals and in many finishes, having a projecting spur on the back that, when driven into the wood, firmly attaches the ornamental head in place. They contribute effectively to the decoration of important doors, especially extension doors of churches and public buildings.
96. Hand and Bevel of Doors.—Many locks and butts used at the present time are made reversible; that is, they can be used for either right- or left-hand doors. Others are not, and must therefore be specified as right hand or left hand. In this latter class are included loose-joint butts and most locks, the operation of which is different on one side than on the other. All locks with beveled fronts are not reversible, and their use should be avoided where no real need of them exists.
A reversible lock is one having a beveled latch bolt that can be turned over, or reversed, at will, to make its bevel face the opposite direction. This is usually accomplished by removing the cap of the lock and turning over the latch bolt.
Fig. 134
In order that hardware may be ordered intelligently, the hand and bevel of the door should be given where the hardware is not interchangeable, or reversible. Rules to determine the hand of doors have, therefore, been established by the manufacturers of hardware, so that the information may be founded on a uniform basis. Reference to [Fig. 135] will materially assist in the interpretation of these rules.