As indicated by the caption, this undated image shows Henri-Léon Gréber's dynamic fountain with four allegorical bronze equestrians figures personifying the world’s great rivers.
The caption accompanying this image reads as follows:
Henri-Léon Gréber's dynamic fountain, with four allegorical bronze equestrians figures personifying the world’s great rivers, was equipped, from the start, with electric lights. Under water, they mimicked the rainbow.
Obviously the word "equestrians" is a typographical error that should be the "equestrian" instead.
Three other images of the "Fountain of Rivers" have also been placed in the Library:
Henri-Léon Gréber's dynamic fountain 1924 at Harbor Hill
One view of Henri-Léon Gréber's dynamic fountain after 1957 installed at Mill Creek Park adjacent to the Country Club Plaza in Kansas City, Missouri.
Another view of Henri-Léon Gréber's dynamic fountain after 1957 installed at Mill Creek Park adjacent to the Country Club Plaza in Kansas City, Missouri.
See Harbor Hill, Clarence Hungerford Mackay's Mansion.