Pages from stage illusions and entertainments

STAGE ILLUSIONS The first part of the work would be to lay the stage.

This should be solid and strong, and on this account the joists and all the supports must not be less than 4 in. by 3 in. The height at the front should be 3 ft. 6 in., and the floor must rise J in. in every foot towards the back. Each row of supports, therefore, will require to be 1J in. higher than the row in front.

If the stage were extended to its full depth, it would be 10 in. higher at the back than the front.

Fig. 4 shows the underwork as it would appear looked down upon from the front. In this figure A is the front of the stage, and the positions of the cross pieces are shown. These are 12 ft. long, and each has four supports, each 3 ft. 2 in. high; there is one support at each end and one 3 ft. from each end. The middle strut is one of the supports of the centre beam, 3 (Fig. 4). When fixing the stage, this would be the first to put up ; 1, 2, 3, 4 and 5 are placed over 3, each 3 ft. apart, and the whole firmly bolted together with carriage bolts, the joints being strengthened by means of metal plates (see A, B, Fig. 5). It will be seen that these trestles are double, and if one be drawn 3 ft. one way, and the other the same distance the other way a stage 18 ft. wide would result (see Fig. 6).

This would bring the supports c D close to the centre.

If it was desired to make the stage wider still, it is obvious that supports c and D would not pass the centre one, therefore, they would have to be taken off and shifted, and when the trestles were drawn out as far as required, would have to be put back again,