Use of an array of solid‐state detectors in conjunction with a magnetic analyzer as a replacement for nuclear emulsions in nuclear spectroscopy is described. Arrays of both Au‐Ge and gold‐doped silicon have been used. The arrays consist of twenty detectors each and cover two inches along the image plane of the magnetic spectrograph. Particles of the same magnetic rigidity, but different mass, are easily identified as their energies are in the ratioZ2/m. The silicon detectors, which operate essentially as parallel plate ionization chambers, suffer the disadvantage of becoming polarized. The use of such arrays reduces by a factor of the order of twenty the time required to extract precision data from a nuclear reaction.