8 



becoming country-wide. I notice that the Toledo Btoard of 

 Trade has sent two representatives to attend this meeting, and 

 that they are here to-day. Another indication of the interest which 

 the work is acquiring ; the Clinton Hill Improvement Society, an 

 association of eight hundred prominent business men of Newark, 

 has seen fit to send a delegate to attend this meeting, and we 

 hope to hear from him before the session is over. 



The first paper on our 'program is : "The Place of Dikes, 

 Sluices and Tide-gates in Mosquito Extermination," by Mr. 

 James E. Brooks, of Glen Ridge, N. J. Mr. Brooks is .the con- 

 sulting engineer of the Essex County Mosquito Commission. 



The Place of Dikes and Tide-Gates in Mosquito Control. 



BY JAMES E. BROOKS, M.E., GLEN RIDGE, N. J. 



The last yellow fever epidemic in New Orleans came after the 

 discovery that the disease is transmitted by a species of mosquito 

 known as the "Stegomiyia." Before this. epidemic was checked, 

 so much had been printed and said about these mosquitoes, their 

 life habits, and their relation to yellow fever, that even the news- 

 boys on the street could identify a yellow fever mosquito and 

 tell the latest way of exterminating it. 



It is no longer necessary to explain to most people that mos- 

 quitoes spend the first few days of their life in stagnant water, 

 and that they do not multiply in the grass and bushes. Nearly 

 everyone knows that only the adult female stings ; that she flies 

 with an aeroplane and carries poison and disease for her vic- 

 tims; that the salt-marsh varieties can migrate as far as forty 

 miles and defy all the defense which man has devised. 



The fight against the adult mosquito is simply hopeless, but 

 fortunately the infant mosquito has no monoplane and must live 

 in water, like a submarine. Eike the submarine of human design, 

 the infant mosquito must come to the surface at frequent inter- 

 vals to breathe through a periscope. This is the reason that 

 oiling pools of stagnant water kills the mosquito larvae; the 

 periscope will not penetrate the film of oil on the surface of the 

 water, and the mosquito dies for lack of air. 



