One of the rarest magic lantern slide, the Choreutoscope. Invented in the 1860s this is one of the earliest attempt at  a projecting phenakistiscope. The mahogany frame bears the stamp of T.H.MacAllister, New-York.
A star wheel moves the images one by one as the crank is turned, a Maltese cross covers the hole as the change of image happens, it does work!
In good condition and in working order, the skeleton is painted on a disk of thin mica and it has survived remarkably well, 25.5 cm x 10 cm or 10" x 4".