aeroscope
/ˈɛːrə(ʊ)skəʊp/noun
1Any of various instruments for estimating the concentration of particles in the air by causing them to impinge on a surface to which they adhere.
2A kind of hand-held motion picture camera driven by compressed air. Now historical.
Origin
Early 19th century (in an earlier sense). From aero- + -scope. Compare earlier aeroscopy.