370 MOSQUITOES OF NORTH AMERICA 



volatilized over a lamp of some kind for every 1000 cubic feet of space. A 

 special apparatus for the purpose has been perfected by Doctor H. A. Veazie, 

 of New Orleans, but a simple apparatus may be made from a section of a stove- 

 pipe, cut so as to have 3 legs and outlets for draft, an alcohol lamp placed be- 

 neath and a flat-bottomed basin on top. The substance is inflammable but the 

 vapor is not explosive. The vapor is not dangerous to human life except when 

 very dense, but it produces a headache if too freely breathed. One of the 

 writers (Howard), in New Orleans on the 8th of November of the epidemic year 

 (1905), in company with Doctor J. H. White, in charge of the Public Health 

 and Marine-Hospital Service operations in the city during the epidemic. Doctor 

 Eupert A. Blue, Doctor Richardson, Doctor H. A. Veazie, and several other 

 assistant surgeons in the service, took part in the fumigation of a room contain- 

 ing about 1200 feet of space. A number of specimens of Culex quinquefasciatus 

 were flying about the room. There were 2 boxes, each about 1 foot long with 

 gauze sides, containing ^ dozen or more live mosquitoes each ; there was a large 

 tube, 2 inches in diameter, and possibly 1^ feet in length, the mouth of which 

 was covered with mosquito bar and which lay on its side on the mantle piece and 

 contained several live mosquitoes. About 6 ounces of the mixture were vola- 

 tilized and the room was kept closed, without any effort to artificially stop 

 cracks, for exactly one hour. Upon re-entering and airing the room, all mos- 

 quitoes were found to be dead and a cockroach was also found dead on the floor, 

 having come up from between the cracks. The vapor is lighter than air, and the 

 mosquitoes in the room, previously unnoticed, soon after fumigation sought the 

 lower air strata of the room, gradually descending towards the floor and towards 

 the windows which were on one side of the room only. Sheets of manila paper 

 had been spread before each window and on these sheets, at the end of the hour, 

 were found dead all the mosquitoes to be found in the room. 



An account of experiments with this mixture, containing details of apparatus, 

 etc., by Past Assistant Surgeon Berry, of the U. S. Public Health and Marine- 

 Hospital Service, is published in the Public Health Eeports for February 2, 

 1906, vol. 21, No. 5, pp. 83 to 89. The conclusions reached by Doctor Berry 

 are as follows : 



" 1. Culicide in the proportion of 4 ounces per 1000 cubic feet used for 2 hours 

 with apparatus similar to that used by us kills Culex pungens, Stegomyia, and 

 Anopheles maculipennis and temporarily stuns the house fly. 



" 2. In the proportion of 3 ounces to 1000 cubic feet it does not always kill the 

 Anopheles maculipennis. 



" 3. Culicide takes fire spontaneously if heated sufficiently. It is therefore 

 necessary to keep the liquid at a certain distance from the flame ; it is also better 

 to have more than one basin in a large space, and about 8 ounces is the maximum 

 quantity to use in one pan. All large cracks must be pasted up — the doors and 

 windows if loose fitting. Gummed paper spread under a window left light would 

 be of great benefit. (I concur with Passed Assistant Surgeon Goldberger as 

 to the closing up of large cracks, but more for preventing weakening of the 

 strength of the gas in the room by diffusion than from any belief that insects 

 might escape from the room.) 



