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(6) Light traps. If you have a suitable place a light trap on 

 the American moth trap principle will often pay most amazingly, 

 but it is not much good in a town where there is a lot of artificial 

 light about. Such traps are not difficult to make, but are some- 

 what dear to buy, and my friends who work them tell me that 

 they find a well diffused light of fair power better than an intensely 

 bright light of small dimensions, which will perhaps be better 

 understood under the next heading. 



(7) Light work. My brother and I have been working light 

 on the following principle, obtaining many insects of undoubted 

 interest by it. 



First, we use a large sheet suspended by the corners, to which 

 are strongly sewn stout brass rings. Have plenty of strong blind 

 cord, throw the cord by a small lead weight of about 2lb. over 

 the bough of a tree, detach your weight, and leave the cord 

 hanging, next throw another cord over the bough about twice 

 the width of your sheet down the bough. Make fast one Hne 

 to each upper corner of the sheet and pass the free end through 

 the rings, next drive into the ground two longish stakes with 

 holes in the end at such an angle that they will withstand the 

 strain on the sheet, pass the lines through the bottom rings, then 

 through the eyes in the stakes, and finally through the bottom 

 rings, haul taut and make fast to the bottom rings. Your sheet 

 will now be tightly stretched, like a lantern sheet. The sheet 

 should be white or nearly so. A loose flap at the bottom touching 

 the ground is an advantage. Stretch at right angles to a ride 

 or path, and moderately high up. 



To Illuminate your sheet. We use a 10-inch Rushmore 

 Searchlight (costing about £8 to £9), because we happen to 

 have one. I have procured quite good results with bicycle lamp 

 on the same principle, i.e., the Mangin lens mirror, costing only 

 24/- Acetylene gas is convenient and clean. Use a separate 

 generator, coupled to a horsehair scrubber, this gives a supply of 

 fairly clean acetylene gas. There is room for experiment as to 

 that part of the spectrum which is most attractive to insects. As 

 will be known to most of you, acetylene is very rich in the violet 

 end of the specrum. 



The moths come to the illuminated sheet at all hours of the 

 night, but best from 11.30 to 1. As a rule they come in little 

 parties of several different species together, followed by a lull. 

 We simply sit on a camp stool and wait, one each side of the sheet, 

 and net them as they come in. (See Note A). 



Note A. — Since I addressed the Society I have been working in the Pens in conjunction 

 with a professional collector. He averred that I did not want much teaching about setting a 

 lamp and sheet, but as his methods, and mine were rather different, and I thought in some 

 respects better, I will give them. Like me he set his sheet across the wind and kept his lamp 

 on the lee side. Unlike me, he used a lamp open at three sides, and with only the dark side 

 away from the sheet. He also did not use a scrubber. Now several species came freely to his 

 light which did not come to mine, and vice versa. I believe that to be due to the fact that his 

 light was more diffused, and being open at the side, some insects were first attracted by the 

 flame and then got into the area of the sheet light. Some seemed to prefer the lamp to the 



