Proceedings of Fi^th Annual Meeting 19 



In Westfield the Union County Mosquito Commission started 

 to improve the lake in the center of the city, part of the expense 

 to be borne by the town of Westfield. This work was so suc- 

 cessful that they have appropriated $80,000 to continue to make 

 a park at the upper end of that lake. 



We are going to try to keep on the good work and see if we 

 cannot make 191S better than any previous year. 



President B^inkerhoi^f — The next report in our sympo- 

 sium is from Middlesex County, by Dr. Headlee. 



Prog:ress in Mosquito Work in Middlesex County 



BY THOMAS J. HEADI^EE^ PH.D., NEW BRUNSWICK_, N. J. 



In Middlesex County the work has been primarily a matter 

 of attending to the salt marsh, of which we have about 8,000 

 acres. A little fresh-water work is done, but that fresh-water 

 work is supported entirely, except for the supervision, by local 

 funds. 



On the marshes of Middlesex County we have now nearly a 

 million feet of ditching; to be exact, about 995,000 feet. That 

 is about half of what we need. This year we have put in nearly 

 117,000 feet in spite of the labor conditions, and we have done 

 that primarily by means of a ditching machine. 



We have a special problem in Middlesex County consisting 

 of the contamination of the salt marsh by an acid-charged 

 effluent from guncotton works. We have three great powder- 

 mills that are constantly contributing to the pollution of the 

 salt marsh. We have the Hercules Powder Plant, the DuPont 

 Works and the Nixon Nitration Works. The two first-men- 

 tioned are on the south side of the river, near the town of South 

 River, and pour their effluent into South River, which empties 

 ijito the Raritan. The third, the Nixon Nitration Works, 

 empties its effluent into what we call Redroot Creek, which 

 drains down into the Raritan River. Until recently the effluents 

 were above 3: per cent acid, consisting of about 2 per cent sul- 

 furic and I per cent nitric. So long as the effluent was dis- 

 charged continuously into Redroot Creek we had no particular 



