SEWAGE CONTAMINATION OF OYSTER BEDS. 209 



Hesults. — The bacteriological examination of an}" large bod}^ of water 

 resolves itself into an analysis of series of samples taken from various 

 sections of the stream. So in this survey of the Providence River col- 

 lections were made first at the head of the river, then, proceeding 

 downstream, at intervals of varying distance until the polluted area 

 was passed. For the sake of brevity, the localities at which collections 

 were made will be spoken of hereafter as "stations," and they have 

 been indicated on the map by large dots. When possible, they were 

 chosen near some prominent landmark, so that they might be more 

 easily found a second time, since in many instances several trips were 

 made in order to observe the effect of varying conditions of tide and 

 weather. 



The evidences of sewage pollution of both the water and shore in 

 the neighborhood of Fields Point were very obvious. Below the point 

 the west bank of the river falls abruptly away from the eastern shore, 

 taking a westerly direction for nearly half a mile, when it again 

 resimies its general southerly course. The deep water of the river 

 follows closely the eastern shore, so that a large area of shoal water is 

 formed south of Fields Point, extending out beyond Starve Goat 

 Island. This section of the river is therefore out of the direct tide 

 current, which naturally follows the channel along the east shore, and 

 the water is consequent!}^ rather sluggish. It is a dirty gray color, 

 which is due to the large amounts of sediment in suspension. Also 

 the beaches within a quai'ter of a mile of the sewer outfall are usually 

 covered with foul-smelling slime and collections of sewage refuse, left 

 there by the receding tide water. Before the Fields Point sewage 

 station Avas put into operation this shoal was a famous natural oyster 

 bed, but it has been abandoned for a number of 3'ears. At the pres- 

 ent time quantities of seed oysters are taken from this locality in the 

 spring of the year and planted on beds farther down the river. The 

 beaches in this neighborhood also produced an abundance of clams. 



In the section of the river above described the first series of water 

 samples was collected at 11 stations situated in an area at no point 

 more than half a mile distant from the outlet of the main sewer. 

 Commencing on the northern shore of Fields Point, these stations 

 were located as follows: Station 1, halfway between the ship channel 

 and the northern shore of the point, directly off the outfall of the 

 "storm" sewer; station 2, off the end of the steamboat landing; 

 station 3, directly over the outlet of the main sewer; stations 4 and 5, 

 in deep water on opposite sides of the channel, a short distance below 

 the point; stations 0, 7, and 8, in the shallow water on the flats run- 

 ning out from the southern shore of the point; stations 9 and 10, in 

 about 10 feet of water near Starve Goat Island, and station 11, in the 

 ship channel just off buoy No. 11. Perhaps the exact situations can 



F. C. 1904—14 



