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at Suiimiit, N. J., in woodland pools and swamp land, and its use on a 

 large scale is being attempted the present year in the vicinity of a arge 

 town on Long Island. Dr. A. D. Hopkins, of Morgantown, W. Va., 

 tells the writer that a])out ten years ago an extensive pumping station 

 was located near the river liank where the oil pipe line crosses a mile 

 above Morgantown and that the oil frequently escapes out over the 

 river. Since that time the city has been almost exempt from 

 mosquitoes. 



In 1897, Mr. M. J. Wightman, while interested in developing a new 

 resort knowji as Midland Beach, had -t barrels of (?rude petroleum 

 scattered over the marshes surrounding the beach. For three weeks 

 previously the mosquitoes had been unl)earable. The employees at 

 the beach went about w ith their heads covered with netting, and of 

 course this had a very discouraging influence upon visitors. The 

 oiled district covered a radius of half a mile, and Mr. Wightman, writ- 

 ing in 1800, stated that within three days after the oil was distributed 

 mosquitoes wa^re rare along the beach. This condition lasted through- 

 out the season. Recently, owing to a change of management, the 

 writer is informed that nothing has been done and that mosquitoes 

 have become plentiful again. 



Dr. St. George Gray, of St. Lucia, British West Indies, writes, after 

 reading Bulletin 1 of this office, that he has tried kerosene in his well 

 and in the water jars in his yard with the result that one species has 

 disappeared from his house and that the other mosquitoes give; him 

 very little trouble. 



The remedial experiments against uiosquito larva? tried by Doctors 

 Stephens and Christopher at Sien-a Leone are given in the reports to 

 the malaria committee of the Royal Societ}^, London, July 0, 1000, 

 They selected as the most practical larvicides kerosene (paraffin oil) 

 and salt. The salt, requiring a very strong solution, was not experi- 

 mented with extensively. A few handfuls thrown into pools contain- 

 ing not more than 3 or 1 pints of water produced no effect in three 

 days. With kerosene the rock pools and small runnells of water were 

 treated: "The larvicidal effect in the pools was very striking, most of 

 the larvte being killed in fifteen minutes or less. In many cases again, 

 besides the larvicidal effect, adult females were found next day killed 

 l^y the paraffin on the surface of the pool where they had come to lay 

 their eggs." Thus the writer's 1893 observation on the non-deterrent 

 effect of the kerosene film on adult mosquitoes and their resultant 

 destruction before the eggs are laid is confirmed. This has always 

 seemed to be a point of great practical value in the use of kerosene. 

 The final result by the English observers, however, was found to be the 

 inmiediate return of the insects on the cessation of the application of 

 petroleum. An interesting test experiment was made by them upon a 

 surface drain arising from a spring and running for 300 yards when it 



