Eurekas are toy index typewriters that are usually found rebranded for other companies. Most notably, during the first quarter of the 20th century, a German chocolatier sold it alongside a box of chocolates and stationary. That chocolatier was Stollwerck GmbH which was named after founder Franz Stollwerck (1815 - 1876). For this company the typewriter was rebranded as the Stollwerck. Stollwerck typewriters were embossed with the company name on the daisy wheel so they were easily identifiable. Other examples were rebranded as La Française and, like the one on this page, the American, both of which were marketed to Francophones.
The actual manufacturer of these typewriters was a French company by the name of Kratz-Boussac which was founded in 1883 by Henri-Kratz Boussac. In 1910, about when the Eureka was produced, the Boussac factory was located in Eure, France with offices in Paris. The company produced a line of Eureka branded products, including this typewriter.
This simple typewriter works by turning the daisy wheel with the wooden handle to the desired character then pressing downward to print. A roller sits atop the daisy wheel which applies ink as each character passes under it. The typewriter has a crude wood platen with feed rollers underneath to pull through sheets of paper. They were available in several finishes such as green, red or brass plated and most came with a base and dome-top cover made of a composite material.