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The 40-channel magnetograph is described. Special attention is given to details of the fiber-optic probe which dissects the Fraunhofer line image and provides for a choice of spectral and spatial resolution. Examples of magnetograms taken with the instrument are shown. Maps of quiet areas, made with long integration times to achieve a noise of 0.4 G, yet with 5 arc-sec resolution, indicate the presence everywhere of a minimum background field of average strength 2–3 G.