The process is a simple one, requiring for its manipulation to obtain best results, prepared, or heliographic paper, a copying frame, glass and cushion, which may be obtained of dealers in artists' materials. In use the frame is laid on the glass side, the back and cushion removed. The tracing or drawing (which has been made with deep black India ink upon tracing paper or cloth) is laid on the glass face downward, the prepared paper placed over it, the prepared side next to the tracing, the cushion placed over this and the back of the frame closed. Care must be used to have the tracing, the prepared paper and the cushion perfectly smooth, so as to insure the perfect contact of the tracing and paper. Reverse the frame and expose to the light for from six minutes to an hour, according to the degree of light. Remove the prepared paper and drench in clear water ten minutes or more, and hang by one edge to dry. The prepared paper requires to be entirely shielded from daylight before being used and while putting it into the frame. Where all the regular materials are not at hand the cushion may be a smoothly-folded blanket placed upon a board, and on this laid successively the prepared paper, the tracing and the plate glass.