An astronomer seated at a table, holding a compass and an armillary sphere, looking at a board inscribed with geometric figures

A comparable drawing of an old man looking through a window with a telescope by Leprince is in the Muse des Beaux-Arts, Quimper, S. Barthlmy, Dessins franais XVIIe-XIXe sicle, exhib. cat., Quimper, 1999, no. 50.