Denis Gifford called Ralph Morgan's MONSTER MAKER character, drugged and chained in the lab, "the most sickening sight in pre-Hammer horrors" -- I'm pretty sure that's an exact quote.

Welllllll, I think pre-Code horrors had more "sickening" sights -- but if he'd written "most sickening sight in a '40s horror movie" he might have been on to something. And, funnily enough, trying to think of another disturbing sight in a '40s horror movie, I came up with another Ralph Morgan character: Kurt Ingston in NIGHT MONSTER, sitting in bed with one (fake) arm and no legs.