So much has been written on the zodiacal light that it may appear rather rash to say that a really accurate examination of this phenomenon has yet to be made. Still I have no hesitation in saying that neither its position, its shape, nor its spectrum has yet been determined with sufficient accuracy. In the hope of being able to add something to our knowledge of the last of these, I obtained, in 1882, a grant from the Government Grant Fund for the construction of a spectroscope specially designed for observing and, if possible, photographing the spectrum of the zodiacal light. The apparatus, which was made by Mr A. Hilger, consists of two interchangeable collimators of 36 inches and 8 inches focal length and 1½ inch aperture; an Iceland spar prism 1¼ inch high, 2¼ inches side, a camera with a lens of 8 inches focal length, and an observing telescope and a heavy glass prism which can be used for eye observations. The camera and telescope are fixed to a common base movable about a pivot concentric with the pillar carrying the prism, so that they are readily interchanged. The lenses are all of quartz, and the dark slide carrying the sensitive plate can be placed at such an angle that the whole or at least a considerable part of the spectrum is in focus at the same time.