entering the supply. Thus new fields of work have been opened to the laboratory. The center of gravity of the system is now much farther from the city than formerly, and the logic of the situation points to the future establishment of a laboratory upon the watershed operated in connection with a department of sanitary inspection and equipped for chemical as well as biological work.
In 1893 the Public Water Board of the city of Lynn, Mass., fitted out a small room in the basement of the City Hall to serve as a laboratory for microscopical work. Weekly samples were collected from the supply ponds and examined by one of the lady assistants in the office. The results of the examinations were used by the superintendent in the operation of the works, and in several instances
they proved the direct means of preventing the consumers from receiving water of an inferior quality. They also resulted in the undertaking of improvements in one of the reservoirs and tributary swamp areas that materially reduced the growths of troublesome algæ.
Bad tastes and odors in the water supply of Brooklyn, N. Y., led to the establishment of Mt. Prospect Laboratory by the Department of Water Supply in 1897. As this laboratory is typical of its class it deserves more than a passing notice. Situated upon the shore of Mt. Prospect Reservoir, near the entrance to Prospect Park, the laboratory has a fortunate location. In addition to being within convenient distance of the office of the department, the main distribution reservoirs of the city and the railway depot at which samples from the watershed are