AN APPARATUS FOR TESTING THE VALUE OF FUMI 



GATING AGENTS.* 



Arthur I. Kendall, 



Acting Chief, Board of Health Laboratory, I. C. C, Panama. 



CoiNCiDENTLY wilh our incrcascd knowledge of the part played 

 by mosquitoes in the spread of malaria and yellow fever there has 

 arisen a demand for a class of substances which shall be efiicient in 

 killing these insects. 



Although the introduction of preventive measures for these dis- 

 eases is a comparatively recent event, the number of substances — 

 "Culicides" — proposed for this purpose is very great; in fact, there 

 are approximately as many culicides as there are disinfectants for 

 bacteria, although our knowledge of the latter is much the more 

 complete. 



There is this difference, however, between the two classes of sub- 

 stances above mentioned, namely that whereas the bacterial fumigation 

 has been studied with great care and detail, with gradually perfected 

 apparatus and methods, the mosquito fumigation is still in the rule- 

 of-thumb state, and we have no very definite data based upon careful 

 experimental procedures upon which to compare the relative 

 efficiency of different culicides. This is due, to a considerable 

 extent, to the fact that at present there is no method or apparatus 

 which will allow such comparison. 



The writer has had occasion to construct an apparatus for this 

 purpose which has given satisfaction in actual use, and which has 

 furnished a ready means of demonstrating the applicability of the 

 various culicidal substances which from time to time have been 

 proposed in this connection. 



Before describing the apparatus in detail, it v.Ill be well to con- 

 sider what one must know about a fumigant; confining ourselves to 

 salient points, omitting details which are of lesser importance. 



One must consider cost, availability (including continuous sup- 

 ply), killing (orculicidal power), effect upon furnishings (or in 



♦Received for publication February 17. 1906. 



