Hoffmann (Professor), 1839-1919 · New York : E.P. Dutton & Co. ; London : George Routledge & Sons · leaf 43
Later Magic 13 utility is discounted by the necessity of using the con- jurer's own head-gear, a proceeding naturally giving rise to suspicion. The little appliance which I am about to describe is not open to that objection. … Fig. 8. The apparatus in question (Fig. 8) consists of an oval disc of pasteboard, a a (in size a little less than the crown of a hat), to which is attached, by means of a hinge of cloth or leather, an upright partition, b. Though shown upright in the diagram, this partition normally lies flat on a…
