An ingenious and elegant invention of the late Dr. Wollaston, for the purpose of facilitating the delineation of objects, by producing a reflected picture of them upon the paper. It consists of a solid prismatic piece of glass, mounted upon a stem capable of elongation or contraction, and which can be screwed at the foot to a table or drawing board. The prism has its angles so arranged, that the rays from the object are reflected upon the paper, and is covered at top by a metallic eye-piece, the hole in which lies half over the edge of the prism, so as to afford to a person looking through, a view of the picture reflected through the glass, and a direct view of his pencil or tracing point. By means of this instrument, a person unacquainted with drawing may delineate objects with great ease and accuracy. For specimens of the capabilities of this instrument, we would refer to the volume of plates to Capt. Basil Hall's Voyage to the United States of America, the whole of which, consisting of representations of scenery, animals, portraits, etc. were sketched by means of this instrument by Capt. Hall, who had no knowledge of drawing.