D6 
at Summit, 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 about ten years ago an extensive pumping station 
was located near the river bank 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 nO excmys from 
mosquitoes. 
In 1897, Mr. M. J. Wightman, while interested in developing a new 
resort known as Midland Beach, had 4 barrels of crude petroleum 
scattered over the marshes surrounding the beach. For three weeks 
previously the mosquitoes had been unbearable. The employees at 
the beach went about with 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 1899, stated that within three days after the oil was distributed 
mosquitoes were 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 4 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 TRORGIN SOEs give him 
very little trouble. 
The remedial experiments against mosquito larvee tried by Doctors 
Stephens and Christopher at Sierra Leone are given in the reports to 
the malaria committee of the Royal Society, London, July 6, 1900. 
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 4 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 larve being killed in fifteen minutes or less. In many cases again, 
besides the larvicidal effect, adult females were found next day killed 
by 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 
immediate return of the insects on the cessation of the application of 
petroleum. An interesting test experiment was made by them upona 
surface drain arising from a spring and running for 300 yards when it 
