aquila | dumb procurement
02|03|04

BTH (British Thompson Houston) were formed around 1880, the UKs foreign arm of Thompson Houston who eventually became GE (General Electric - hence the similar logos). BTH continued as a separate company for years, eventually being merged into AEI (Associated Electrical Industries) in 1960. Whilst all this electrical history is moderately interesting, it goes to show that these projectors were over forty years old.