VI 



be infected by having previously bitten infected persons. 

 This means, also, can be adopted only by the rich, and is 

 sometimes very inconvenient even to them. 



While all these measures are undoubtedly beneficial, 

 particularly under special circumstances, the question 

 strikes us at once, " Rather than take so much trouble in 

 protecting ourselves from the bites of these insects, would 

 it not be better to get rid of them at once ? " 



Where this measure can be carried out, not only the 

 rich, but the whole population will be protected ; and 

 individuals will be saved the trouble and expense involved 

 in providing their houses with wire-gauze screens. 



The object of the present work is to show how we can 

 best wage war against mosquitoes. The information given 

 is based upon experience gained by me during many years 

 study of mosquitoes in various parts of the world ; and 

 more especially upon the actual results of the operations 

 now being carried on by the Liverpool School of Tropical 

 Medicine in West Africa. The work is not written only 

 for medical men in the tropics, but for anyone who lives in 

 countries where mosquitoes abound. I have tried to 

 describe the various operations in detail ; and the Appendix 

 contains accounts of the campaigns already started in 

 various parts of the world. 



The reader will perceive that, in fact, I am preaching a 

 general crusade of a more novel and perhaps more useful 

 character than most crusades. I trust that he will 

 volunteer under the flag. 



LIVERPOOL, i^th October^ 1901. 



