............................................................. 137
Building Precision Machine Shop, Period III: 1915-1931 ............................................. 153
THE POST-EDISON YEARS: Period IV: 1932-1962 .............. 144
Building Third Floor, Storage Battery Test Department........................................ 146
Building Third Floor, Central Open Area....................................... 152
Building Powerhouse, Period 1887-1900 ........................................................ 161
Building Chemical Store Room............................................ 146
Building Third Floor, Educational Film Studio................... 151
Albert Petit’s experimental room .................................. 140
Building Second Floor Vacuum Pump Room and Glass
Blower’s Room, Period II: 1901-1914........ 163
Building Library . 141
Building Room .............................. 142
Building Drafting Room, Period 1887-1900 and Period II:
1901-1914 ................ 152
Fred Ott’s experimental room.. 165
Building General .. 165
Ediphone Development.......................... 144
Building Third Floor, Period II: 1901-1914 and PeriodIII:
1915-1931 ...... 162
Building Pattern Shop..................................................................................................... 141
Building X-Ray Room.................................. 143
Building Drafting Room, Period III: 1915-1931 ........................... 165
Engineering Department ............................................... 153
Building Period II: 1901-1914.... 162
Building ........................................... 151
Building Third Floor, Offices (South Side) ................................................................................................................................................................................................................... 152
Photographic department.... 140
Building Second Floor Experimental Rooms, Period 1887-
1900 and Period II: 1901-1914.... 144
Building Third Floor, Lamp Test Room ..Building Precision Machine Shop, Period II: 1901-1914 .......................................................................................... 139
Building Second Floor Vacuum Pump Room and Glass
Blower’s Room, Period 1887-1900 .......................................... 151
Building Third Floor, Music Room ............................................................................... .............................................. 160
Building ............................................ 154
Building .................................. 164
Building Machine Shops.......................................................................................................... 144
Building Third Floor, Recording Studio ................................... 166
vi
........................................................................................................................................................... 143
Building Third Floor, Period 1887-1900 ........... 154
Historical Occupancy and Furnishings.............................. 165
Historical Research Department................................................ 141
Building Second Floor Experimental Rooms, Period III:
1915-1931 .............................................................
