[The Australian Panther]

J. R. Bray is quite a significant figure.
Here is what Allmovie.com has to say about him.
[The father of modern animation, artist John Randolph "J.R." Bray was born August 25, 1879. Beginning his career as a magazine artist, he first entered animation in 1910 with The Dachshund and the Sausage, the first cartoon ever to contain a structured narrative. Within four years, Bray had created a system whereby a single background image would be reprinted on hundreds of sheets of tracing paper, creating a series of translucent overlays which were then combined with animated characters to foster the appearance of a cohesive scene. He soon teamed with another cartoonist, Earl Hurd, who devised a similar technique utilizing transparent celluloid sheets, later inking his characters directly onto the celluloid. Bray took the process to the next level by introducing multiple layers of celluloid, each with a distinct element of the scene; the fusion of ideas ultimately simplified animation production to an unprecedented degree.

Quickly, the Bray-Hurd technique became the industry standard]
But that's not all folks!
['even the brand of surreal humor so long a staple of the more famous Warner Bros. studios evolved under Bray's guidance. He died in 1978.']

Detailed article here.
http://www.animation-now-and-then.com/page21.htm
Cheers!

Link to the book: Teddy Bears at the Circus