The cornelele is a blend-instrument between the renaissance cornetto and the Hawaiian ukulele.
There are many historical examples of double instruments but the involved geometries were much simpler and the result were awkward and impractical, while in this design the cornetto entirely disappears into the body of the ukulele while being entirely functional.
The cornetto and the ukulele belong to entirely different worlds. The first one is a European renaissance wind instrument which went nearly extinct by 1750. The second one is a string instrument which was developed around Hawai in the 1880s. Both instruments never even coexisted in the same place or time yet we can see them now fused into a single functional body.