hodgk] TYPES OF THE BEST NATURE-STUDY 35 



Next, several lessons were given showing how newts and min- 

 nows devour mosquito larvae in the water; with the result, we may 

 hope, of making the children more thoughtful about destroying such 

 harmless creatures. 



Finally, when interest was at a white heat and everyone was 

 asking, "What can we do about it ?" similar lessons were given 

 with petroleum on the water. The magic of it ! A drop of oil on a 

 tumbler full of wrigglers and in a few minutes every one stretched out 

 dead on the bottom. A few drops on a covered aquarium, and next 

 morning every one of the adult mosquitoes caught by the oil him and 

 drowned. 



This was also conclusive and convincing and the proposition to 

 "oil the pools" met with enthusiastic support. Oil was contributed, 

 also money, about three times as much as was needed, and a barrel 

 of gas oil was purchased; and just as the great first brood was about 

 to emerge from the water nearly five hundred school children armed 

 with oil cans and bottles of oil, and with several express wagons that 

 carried five-gallon tanks, began at one end of the brook basin and, 

 under pretty careful direction, oiled every pool on both sides of the 

 brook for nearly a mile. Many hands made quick work and it only 

 took aboutthree hours-from three to about six o'clock-to complete the 

 task. It was my good fortune to be invited and I came home feeling 

 that I had seen the best nature-study excursion of my life. Every 

 minute of it was worth while. I took the picture from farther out in 

 the water in front of the pupils just as they reached the brook and 

 were about to scatter out among the man)' pools. 



After this great excursion a number of the older children volunteered 

 to watch different parts of the district and report if mosquitoes were 

 again beginning to breed, but all reports were negative up to the close 

 of the term in June. The excursion was made about the first of May 

 and about June first I again slipped into my rubber boots and spent 

 an entire Saturday afternoon wading through the worst places and 

 trying to find pools in the brush that had been skipped. Other years 

 the mosquitoes would have made such a trip impossible. As it was 

 I did not succeed in finding a wriggler in the water and did not see a 

 mosquito the whole time. From the amount of oil that was still in 

 evidence, I should judge that people along the brook were wasting a 

 good deal more than necessary to make a sure thing of it. 



I do not wish to leave the impression that everything went smoothly. 

 Even for work as good as this there are bound to be croakers. People 



