King Kong first appeared on movie screens in 1933. Audiences were amazed at the lifelike movement of the film's prehistoric creatures.
It was done with advanced special effects of the day: stop-motion animation.
How is it done? A camera is pointed at the object. A frame of film is exposed, and the camera stops. The object, usually a model miniature, is adjusted. Another frame of film is exposed. The object is adjusted again.
After 24 times, one second of film is produced. When all the frames are played back at the normal speed of 24 frames per second the object appears to move.
Tedious, yes. But the results are fluid and realistic motion. Forms of stop motion animation are still used today.
You can see a model miniature from King Kong at UW's American Heritage Center.