Pee wee and many others on sale now
Professor Welton’s Boxing Cats was created by William K L Dickson and William Heise for the Edison Manufacturing Company in 1894. Their company, Black Maria Studio, in west Orange, New Jersey made the film as independents and had to work through Edison as Edison had total control of film exhibition in the US. 20 seconds long, 27 frames per second, 35mm.
Now you have the answer to when cat videos started.