One of these traps may be constructed as follows at the cost of only a few pence over the price of a small paraffin lamp. Put together a square box, the sides about two feet and the front open, or procure a suitable one from your grocer. Place a paraffin lamp with a bright tin reflector at the back of this, and make a hole in the top just over the chimney to allow the heated air to pass out freely. Three sheets of glass are now to be placed as shown in the sketch (fig. 51), one upright piece completely shutting off the lamp, and two others placed obliquely with a space between them just large enough to allow admission. These must be exactly the width of the box, and should not be permanently fixed, but simply resting on small wooden supports nailed on to the sides. When required for use, it is only necessary to light up the lamp, strew some dead leaves on the bottom of the box, and put the sheets in their places. It will be seen at once that the angles at which they are placed will direct all light-seekers into the lower compartment, whence they are not at all likely to find their way out again; and after vain endeavours to reach the light they finally settle down on the sides of the box or seek shelter among the dead leaves. [Illustration: FIG. 51.--A TRAP FOR CATCHING MOTHS.] Occasionally it happens that an entomologist is lucky enough to claim the friendship of a person who, from the nature of his calling, is peculiarly well qualified to render him great assistance. Thus a friendly lamplighter, expert and patient in the use of the cyanide bottle or pill box, is capable of giving valuable aid at times; and the keeper of a lighthouse has it in his power to capture many a gem that is seldom seen on the wing; but, although much may be done by means of these and other stationary lights, this kind of work does not compare favourably with the night rambles of a naturalist in the very haunts of the objects of his search. For such out-door work in search of moths a good lantern is essential. An ordinary 'bull's-eye' is almost useless, for, although it concentrates a good light on certain objects, the narrow range of its rays constitutes a strong objection to its use for entomological work. For this purpose it is necessary that the rays of light not only pass in front of you, but also shoot off right and left to warn you of the approach of a moth before it is too late to wield the net. This wide range may be obtained by means of three flat glass sides, or, better still, by a bent plate glass front.