An apparatus for the automatic measurement of the coordinates of particle tracks on photographs obtained from bubble, diffusion, and other chambers is presented. The measured coordinates are registered on perforated tape for insertion into a calculating machine. The maximum traveling speed for the tracks in the automatic system is 3 mm/sec. The precision of the coordinate readings is 2.5 mu and the mean-square deviation is 2.5-4.0 mu . It is pos sible to operate the apparatus manually for precise measurement of the coordinates of separate points. (tr-auth)