Take now a strip of 1 in. deal, 15 in. long, and form it with a plough plane to the shape shown in Fig. 49. The part marked A will be 0.375 in. thick, the parts marked B B overhang 0.25 in., and rise from A to B B to the height which the thickness of your setting boards determine.
Divide this down the whole length with a cutting gauge where shown by the dotted lines; glue one of these halves to the side of one of the bottoms of the box, and from here measure off 5 in., which will be the size of your largest setting board for hawk moths. At this point glue down a whole strip, as shown in Fig. 49, which (supposing you have commenced from your left) clips the right-hand side of the first or 5 in. setting board, and the left-hand side of the second. Proceed in this manner until the bottom of the box is covered with setting boards, which will now slide in and out between the 0.375 in. divisions. Turn the box round and do precisely the same with the other half.
As many more insects under, than above, 4 in. in expanse of wing will be captured, the most useful sizes for setting boards, as also the proper proportions of boards and divisions to fill up the bottom of each half of the box, are as follow:
First half. — 0.25 in. strip, 5 in. board; 0.375 in. strip, 4 in. board; 0.375 in. strip, 3.5 in. board; 0.375 in. strip, 3 in board; 0.375 in. strip, 2.5 in. board; 0.25 in. strip = 20 in. total.
Second half. — 0.25 in. strip, 3.5 in. board; 0.375 in. strip, 3 in. board; 0.375 in. strip, 2.5 in. board; 0.375 in. strip, 2.5 in. board; 0.375 in. strip, 2.25 in. board; 0.375 in. strip, 2 in. board; 0.375 in. strip, 1.5 in. board; 0.25 in. strip = 20 in. total.
Fig. 49 — Section of division strips.
There are thus twelve setting boards 15 in. long, of the most useful sizes, contained in this box. The front is still as it was, open. The loose piece of wood, 20 in. by 4 in., must now be cut down the length, and each half must (making 20 in. by 2 in.) be hinged to the top and bottom of the box; a lock can then be fixed to bolt together the two halves, hooks also being fixed at each end of the box to further secure the front flaps. Fig. 50 shows the arrangement of the box at this stage — shut, but with the front flaps lifted up and down, showing the "sliding" setting boards snugly fixed within. Insects may by this method be left on the boards whilst travelling without the slightest risk, as nothing can come loose, and the pins of one side miss those of the other when the box is shut and locked.
Fig. 50 — Front of setting-board box, with flaps open.