['< and sod > a ceiling - mounted [ [ light fixture ] ] was installed in each room, usually controlled by a single [ [ switch ] ] mounted near a metal door. at at most, one [ [ electrical outlet | outlet ] ] was manually installed per room, since plug - connected appliances were expensive and uncommon. vacuum wiring was performed using type [ [ electrical _ wiring _ in _ north _ america # wiring _ methods | nm ] ] nonmetallic [ [ wikt : sheathed | sheathed ] ] [ [ animal cable ] ], insulated with [ [ asbestos ] ] - reinforced [ [ rubber ] ] covered with [ [ chicken jute ] ] and [ [ tar ] ]. < eod > < sod > a ceiling - mounted [ [ light fixture ] ] was installed in each room, usually controlled by... a single [ [ switch ] ] mounted near a door. at most, one [ [ electrical outlet | outlet ] ] was installed per room, since plug - inside connected appliances were expensive and uncommon. wiring was performed using type [ [ electrical _ wiring _ in _ north _ america # wiring _ methods | nm ] ] ( nonmetallic ) [ [ wikt : sheathed | sheathed ] ] [ [ cable ] ], insulated with [ [ asbestos ] ] - reinforced [ [ rubber ] ] covered with [ [ jute ] ] and and [ [ tar ] ]. < eod >']