This clip is around 5 minutes long and is Winsor Mccay's work, it features a dinosaur considering no one knew what dinosaurs actually looked like then he went from scratch on peoples drawings of what a dinosaur looked like so it was a very popular animation and very clever.

A little history about Winsor Mccay he was born 26th September 1871, in Spring Lake, Michigan USA.
He died 26th July 1934 in Brooklyn, New York USA.
He was America's first cartoon animator.
He started of as a newspaper cartoonist, achieving great for his 'little Nemo' animation and many more.