N. J. Mosquito Extermination Association 49 



I do not expect that everyone here will agree that it it is a 

 matter of considerable import, but it seems to me that it is based 

 on a good many years' experience, so I am willing to take the 

 risk of setting before you something which may not entirely meet 

 your judgment. 



introduction. 



This paper, owing to the time limit, must necessarily be con- 

 fined to general principles. Adapting these principles to opera- 

 tions in definite localities is a matter of much more detailed con- 

 sideration. 



NEED OF^ A MEASURE OF IMMEDIATE RESULTS. 



It is a fairly well accepted principle that a unit of measure of 

 some kind must be adopted in any line of endeavor in order that 

 progress made therein may be expressed in some definite and 

 clear-cut way. Mosquito control, the problem which we have 

 come together in this convention to consider, is not an exception 

 to tljis general rule, but a satisfactory sort of unit of measure 

 peculiarly difficult to work out. 



It is comparatively easy to determine how many thousands of 

 dollars have been spent, how many feet of ditch have been cut, 

 how many acres of swamp or salt marsh land have had the water 

 removed from their surface, how many acres have been filled, 

 how many gallons of oil have been used as larvicide, but it is 

 difficult to secure a unit of measure which will tell us accurately 

 the extent to which these efforts have been successful in mosquito 

 reduction, and, after all is said and done, the first result to be 

 measured is the reduction in mosquitoes which such work brings 

 about. Later the effect of this work will appear in advances in 

 taxable values, but. some years must go by before even the begin- 

 nings of this type of result will make their appearance. 



POSSIBI^E KINDS OF MEASURES OE IMMEDIATE RESUI^TS. 



The most natural way of attempting a measure of the effect of 

 anti-mosquito work in terms of the reduction of the mosquito 

 pest is to consult the experience of persons living in the territory 

 where the reduction has occurred. Unfortunately all of the 

 efforts of this sort with which the writer has been familiar have 

 been unsatisfactory because the reports are of such an extremely 

 variable character. It is probable that if everyone living within 

 the territory could be consulted, at say an interval of every two 

 weeks or even 30 days, a pretty fair measure of mosquito reduc- 



4 MOS 



