199 



Correspondence on the Mosquito Remedy. 



An article iu Insect Life written by yon on the prevention of mosquitoes has 

 much interested me. I supposed the plan mentioned by j'ou was ori<riual with me, 

 as I had never seen it proposed before it occurred to me. It appears quite possible 

 to me to treat large tracts of land in the manner you have tried on a small scale. 



x\lthough I have not given the snbject proper scientilic study, I have observed 

 enough to learn that mosquitoes will only breed where there are rather small-sized 

 pools of water that is not agitated and is warmed by the sun. Such pools are found 

 in the salt marshes along the coast. In many places they are, without doubt, too 

 numerous to make any attempt to destroy their contents successful, but in a large 

 number of tracts of salt meadow land there are comi^aratively few collections of 

 water, and here, it seems to me, the petroleum or other insecticide could be effect- 

 ively applied. By careful study and experiment the smallest quantity of the in- 

 secticide could be found and the exact time that it would remain operative. Even, 

 suppose this quantity should amount to large jiroportions and should cost a good 

 deal of money, the advantage gained would be so great that the plan could be car- 

 ried out. To free a mosquito-infested district from the pest, in many parts of the 

 country, would increase values of lauds thousands, perhaps millions of dollars, and 

 land-owners would gladly pay for it. I myself am an owner of laud along the Sound 

 and I would be most happj;- to add my share to a fund to relieve us from the pest. 



Could the plan of ridding a district from mosquitoes be shown to be feasible by 

 some authority on entomology I think an association could be formed to carry it 

 out. Please inform me whether it is within the province of your Department to 

 assist in such an undertaking. If not, perhaps Insect Life might agitate the sub- 

 ject and awaken sufficient interest in the matter to have means provided to test the 

 mosquito destroying plan. — [Dr. Wooster Beach, New York, N. Y., October 14, 1892, 

 to L. O. Howard. 



Reply.—* * * I do not claim to have originated the plan of treating breeding 

 j)ools with kerosene as a remedy against mosquitoes, but it is a remedy which has 

 been floating around in the air for the past twenty years if not longer. I began 

 studying entomology in 1866, and it seems to me that I have always been familiar 

 with the suggestion. It has been published, however, very rarely, and no accounts 

 of accurate experiments have ever been put in print so far as I know, except the one 

 of mine which you are kind enough to comi)liment. I fully believe that in many 

 localities the remedy will pay and that, as you suggest, there is room for further ex- 

 periment, although it seems to me that I have etfectually proved the efficiency and 

 economy of the plan. I have shown that one barrel of kerosene will treat 96,000 

 square feet of water surface and that the effect of this treatment will last longer 

 than ten days, even if rain storms intervene. Calculate for yourself on the basis of 

 the 370 mosquitoes my little experiment killed. All were females. Suppose each 

 female to have laid 200 eggs. Barring accidents, in twenty days there would have 

 been from those 370 mosquitoes seventy-four thousand individuals. One-half of 

 these being females and each laying 200 eggs, in six weeks from the time of my ex- 

 periment there would have been seven million four hundred thousand mosquitoes ! 

 Such ligures as these are to a certain extent defective, but they indicate possibilities 

 and they give at least a faint idea of what can be done by work of this kind early in 

 the season. It is within the province of this Division to undertake experiments of 

 this character, and I think it quite likely that further experiments will be made next 

 season. * « - I can assure you that if I had the misfortune to live in a mosquito- 

 ridden neighborhood I should agitate the matter among my property-holding neigh- 

 bors and I think it would not be difficult to arouse such a public sentiment that ac- 

 tive remedial work would be undertaken. — [L. O. H., October 15, 1892.] 



