Abstract: A spectrophotometer which uses as a detector a silicon photocell and a phototube sensitive to short wavelengths. The light from the sample cell is divided into a smaller and a larger portion. The smaller portion is projected onto the silicon photocell and the larger portion, to the phototube. The two outputs are combined and amplified for indication. The whole of the light transmitted through the sample cell may also be projected to the phototube while the spectrophotometer operates in the short wavelength region and alternatively to the silicon photocell while the instrument operates in the long wavelength region.