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POPULAR SCIENCE MONTHLY.
when they come to the surface to breathe, and so kills them (see Figs. 5 and 6).
In Fig. 5 a 'wiggler' is seen trying to get air, vainly thrusting its breathing tube up into the film of kerosene.
In Fig. 6 the upper 'wiggler' is grasping its breathing tube in its mouth, apparently trying to pull off the small particles of kerosene
with which the tube has been clogged. The 'wigglers' upon the bottom have been suffocated and have given up the fight.
An ounce (two tablespoonfuls) of kerosene will spread over fifteen square feet of water surface, forming a film thick enough to kill all