Page:Popular Science Monthly Volume 66.djvu/290

286 very small section, and the spring of 1905 should tell an interesting story. There will be 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 estimates 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 useful. 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

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 larvæ breed are declared nuisances because 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 consideration 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.