on Mosquito Extermination. 25 



They did not appear to be anopheles. The cisterns I referred 

 to were those about the premises which w^ere scarcely used ; 

 they had no circulating chain pump, and were for use only in 

 case of an emergency in case the water supply should fail. In 

 them we found numerous instances of larvae. I feel that we 

 could have obviated that trouble by screening or introducing 

 gold fish. 



Mr. Claflin: Were the cisterns dark or covered? 



Mr. Matheson : They were very dark. 



Mr. Claflin : Thank you very much, Mr. Matheson. 



Mr. Claflin spoke for about ten minutes, holding the close 

 attention of all present by his recital of the interesting experi- 

 ence of the Morristown, N. J., Improvement Society in drain- 

 age and extermination. On account of his departure from 

 the city for some time the proofs of his remarks could not be 

 corrected by himself, much to our regret, and he advised that 

 only the summary be printed, which w^as given in Engineering 

 News : 



"He prefaced his remarks by saying that sunshine seemed 

 to favor the breeding of anopheles, the malaria-bearing mos- 

 quito, and that it had been a great grief to him to do away with 

 a swamp and pond which were particularly attractive. The 

 swamp gave no trouble until a railway embankment was built 

 through it, increasing the stagnant water, and bringing in, pre- 

 sumably, both anopheles, mosquitoes and malarial Italian labor- 

 ers. Within two years some 25 per cent, of all adult persons 

 living within 1,000 feet of the swamp, previously healthy, were 

 attacked by malaria. Subscriptions were secured, the dam 

 removed, the pond emptied, and the swamp was drained by 

 pipes, supplemented by open ditches where the ground was 

 yet too soft for the pipes. The mosquitoes, previously num- 

 erous, and including anopheles, had almost disappeared from 

 the section, and scarcely an anopheles was found during almost 

 weekly inspections last summer." 



Mr. Claflin : I would like to ask some one, if there is 

 any one here who can tell me, how large and deep a pond 

 should be in order, under usual circumstances, to sustain the 

 life of gold fish and top minnows and such other fish as may 

 best be adapted. Can you tell me, Mr. Weeks? 



Mr. Weeks: I was going to suggest that Dr. Felt answer 

 that. 



