PLATE I. Fig. 1.
EXPLANATION OF THE PLATE.
PLATE I, FIGURE 1.
A B C D E F and E F, the oblong box as shown in fig. 1, Plate I.
A B C D, the top lid of the oblong box; G H, the half of it made to fall back, and supported at an angle by the hinges, h h; l, the upper part of the lock of the box; i k, the two gable ends of the roof; i, the perforated zinc shown as secured in a triangular frame; and k, the outside appearance of the ventilator.
Q Q, the two quadrants, supporting the table, I J, which is formed by the side of the box, A C E E, being let down; a a a, &c., fifteen holes made to receive the back bolt, m, of the observation-frame, Z; b b, two bolts to fasten into the holes, c and d, when the table I J, is closed, f, being the other part of the lock.
T, one of the handles of the box (the other not seen).