The Hardy-Goldthwaite organ was a type of early analogue sampler, similar to the Welte Licht-Ton Orgel, using optical discs of photographed sound waves. The discs, created from translations of original instrumental sounds, rotate between a light a slit and a photo-electrical cell generating outputs of various timbres.
A History of Sampling (Hugh Davies)
Electronic and Experimental Music: Technology, Music, and Culture. Thom Holmes