I have alluded above to a painless mode of doing so, doubtless applicable to all insects. I know it answers admirably with the large moths, so tenacious of life under other circumstances. This potent agent is chloroform, whose pain-quelling properties are so well known as regards the human constitution.
There is a little apparatus[[8]] constructed for carrying this fluid safely to the field, and letting out a drop at a time into the box with the captured insect, taking care that the drop does not go on to the insect. Or a wide-mouthed bottle may be used, having at the bottom a pad of blotting-paper, or some absorbent substance, on which a few drops of chloroform may now and then be dropped. The insect being slipped into this, and the stopper or hand being placed over the bottle's mouth, insensibility (in the insect) follows immediately, and in a few minutes, at most, it is completely lifeless.
But the usual and quickest mode of despatch is by a quick nip between the finger and thumb applied just under the wings, causing, for the most part, instantaneous death: and this can be done through the net, when the
inclosed butterfly shuts his wings, as he usually does when the net wraps round him.
Now take one of your thin pins, and pass it through the thorax of the butterfly, while open or shut, and put it into the corked lining of your pocket-box. So secured, the butterfly will travel uninjured till you reach home; but a heap of dead butterflies in a box together will, in the course of a long walk, so jostle together, as to entirely destroy each other's beauty, rubbing off all their painted scales, when, of course, they are as butterflies no longer.
When you get home, take out all the pins, excepting such as may be stuck perpendicularly through the middle of the thorax, and as soon as possible proceed to "set" your captures.
Preparatory to this, some articles called setting-boards must be provided. A section of one of these is shown in the accompanying cut; but in reality they are made much longer, so as to accommodate a column of half-a-dozen butterflies or more: the breadth may vary,
according to the width of the butterflies that are to be set thereon.
The bottom is usually a thin slip of deal, on which are glued two strips of cork, bevelled off towards the edges, with a slightly curved face. Sometimes, however, the whole board is made of soft pine, with a groove planed down the middle, and with care will answer pretty well; but the corked board is far preferable.