Although it’s not quite the same as watching the original nitrate prints, you can find early color films online. Joshua Yumibe, AM’00, PhD’07, picks some of his favorites.
The numerous “serpentine dance” films from the 1890s
George Méliès's color films (see Flicker Alley's recently released Blu-ray set)
Les six soeurs Dainef (1902)
Sculpteur moderne (1908) by Segundo de Chomón
Le spectre rouge (1907) by Segundo de Chomón
Les tulipes (1907) by Segundo de Chomón
Mills in Joy and Sorrow (1912) by Alfred Machin
Maudite soit la guerre (1914) by Alfred Machin
The restored version of The Cabinet of Dr. Caligari (1920)
Walter Ruttmann’s Opus films, such as Opus 2 (1921)
Ballet mécanique (1924) by Dudley Murphy and Fernand Léger
The Timeline of Historical Film Colors is also a wonderful resource for various color processes