OPERATION The latch bolt is operated from the outside by the handle except when it is locked by key. When so locked, outside handle is held rigid and is disconnected from the spindle allowing the door to be opened by the inside lever at all times. Section showing lock No. 15777C applied in…
![An illustration from [Graphophone patents] (1878)](https://img.insideoutlibrary.com/img/200/ia-graphophonepaten15unit-405-233.webp)
