Glass positive:- Franklin-Adams astro-camera, this shows the instrument with which the photographs were obtained for the Franklin-Adams chart, the lens was a Cooke Triplet of 10-in, aperture, and 45-in, focal length, a few of the 206 photographs obtained are also exhibited, each plate was 15 inches square, and the complete series affords a photographic representation of the whole sky, 15" x 15"