Old call board

Old pretty and large call board of bourgeois house. To call the staff of the pantry or kitchens. The principle of operation: the board was installed in the kitchens where at the office, the master of the house pressed a call button located in the room where he was. At the office a light was displayed on the board coupled with a bell...the light indicated the room where the house staff were asked. Early twentieth century. Dimensions with support 39 X 41. Square 36x36. Glass 26 x26.