Jon R. Roma:
Gresham sequence switches
Jon R. Roma:
Gresham relays and sequence switches
Jon R. Roma:
Gresham close-up of bevel gears
Jon R. Roma:
Gresham sequence switch close-up
Jon R. Roma:
Gresham relays
Jon R. Roma:
Gresham gears
Jon R. Roma:
Gresham sequence switch interlocking system
Jon R. Roma:
Gresham name plate
Jon R. Roma:
Gresham route lever
Jon R. Roma:
Gresham switch controls
Jon R. Roma:
Gresham builders plate
Jon R. Roma:
Gresham route lever
Jon R. Roma:
Gresham model board and control levers
Jon R. Roma:
Gresham exterior
Jon R. Roma:
Gresham track layout