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POPULAR SCIENCE MONTHLY 



very small section, and the spring of 1905 should tell an interesting 

 story. There will he some mosquitoes, of course, because of the 

 Elizabeth, Kearny and Jersey City marshes that are so near by. 

 Elizabeth is showing an intelligent interest in the work and has esti- 

 mates of the cost of clearing up her marsh land, which is not much 

 less than the Newark area. The Kearny meadows at the junction of 

 the Hackensack and Passaic are being filled by immense hydraulic 

 dredges and will soon be not only mosquito free but industrially use- 

 ful. At a number of other places in the state effective work has been 

 done, and it is now all in the direction of permanent improvement. A 



Hand Ditching on the Shrewsbury Kiver Marshes, Early Spring of J904. 



breeding place once eliminated makes a permanent reduction in the 

 supply and is a positive gain. 



By an amendment to the health laws passed during the session of 

 1904, waters in which mosquito larvae breed are declared nuisances be- 

 cause of that fact alone, and the local boards of health are empowered 

 to deal with them. In a number of places proceedings under this 

 law have produced excellent results. 



The investigations made are important as eliminating from con- 

 sideration vast stretches of supposed breeding grounds like the cat-tail 

 areas in the Hackensack Valley; as limiting the number of species 

 which must be dealt with; as showing clearly the natural checks that 

 may be practically utilized; as proving to demonstration that control 

 amounting to practical extermination is not only possible, but not even 

 difficult; and finally as furnishing a scientific basis for practical work. 



