1897.] Biological Studies in Massachusetts. 505 
As the biological laboratory of the Boston Water Works is 
typical of the methods and nature of the work under discussion, 
a description of it will occupy the remaining portion of this 
paper. It was established in the fall of 1889 by Mr. Desmond 
Fitz Gerald, C. E., Supt. of the Western Division of the Water 
Works, and since then the work has been carried on under his 
general direction. Prof. James I. Peck had charge of the 
laboratory during the first few months of its existence; but 
since January 1, 1890, it has been in charge of the writer. The 
working force consists of one biologist, two (sometimes three) 
assistant biologists, and a number of attendants at the various 
reservoirs who devote a portion of their time to the collecting 
of samples, the observation of temperature, etc. The laboratory 
building is situated upon the shore of the beautiful Chestnut 
Hill Reservoir. (Plate XIII.) It isnear the high service pump- 
ing station,from which it receives steam heat and electric light. 
A gas machine supplies it with gas. 
The object of the laboratory work is to ascertain and keep 
record of the condition of the water in all parts of the supply 
at all times. Reports are made weekly to the Superintendent 
and Water Commissioner. These enable the supply to be man- 
aged in the best possible manner so far as the quality of the 
water is concerned, and they have more than once prevented 
water of inferior quality from being sent into the city. 
The work of the laboratory may be considered under the 
following heads: 1. Environmental and Physical; 2. Micro- 
scopical ; 3. Bacteriological; 4. Photomicrographical; 5. Ex- 
perimental. 
1. Environmental and Physical—Samples of water for exam- 
ination are collected weekly from all parts of the supply, 
namely, from Lake Cochituate, the Sudbury Storage Reservoirs 
- and their inflowing streams, the aqueducts, distributing reser- 
voirs and service pipes, and sent by express to the laboratory. 
Glass-stoppered, one-litre bottles are used, thoroughly packed 
in felt-lined boxes. In all the reservoirssamples are collected 
at the surface, mid-depth, and bottom. The following appara- 
tus (Plate XIV.) has been found the most convenient for secur- 
ing samples from beneath the surface. The frame for holding 
