Modern Magic: A Practical Treatise on the Art of Conjuring

The glasses used have no speciality, but the decanter has a small hole in its under side. This is plugged with a pellet of wax, which, however, is instantly removeable at pleasure. Of the three stands, two (those on which the glasses stand) have no preparation, being mere raised shapes of tin. The third is similar in appearance, but is, in fact, a hollow box, with three or four little holes drilled in its upper side, for a purpose that will presently appear. Of the three covers, the centre one is hollow throughout, but the other two have each its upper portion occupied by a hollow chamber or reservoir, divided in two by a vertical partition, and tapering down to a tube with a very small opening. Each of these compartments has an air-hole at the top. (See Fig. 209.)