214 REPORT OF THE COMMISSIOTfER OF FISHERIES. 



Though the river below Bullock Neck does not have the appearance 

 of a sewage-polluted stream, it is possible to isolate B. coll from some 

 samples of water taken from it. A smaller percentage of the samples 

 collected about Conimicut and Naj^att points than of those collected 

 nearer the sewer outlet give tests for tliis organism; it was found in 

 59 per cent of the water samples taken in the neighborhood of Bullock 

 Nbck; in 60 per cent of those collected over the Conimicut beds; and 

 in but 31 per cent of those obtained from the Nayatt ground. It is 

 very evident that the tides play an important part in the purification 

 of this section of the river. Most of the samples which gave positive 

 reactions for B. coll were collected on a falling tide. Samples taken 

 on the flood are, in many cases, free from sewage bacteria. 



Here, then, is an area from 3 to 6 miles distant from the chief sources 

 of pollution, in which the sewage, when present, is diluted to such an 

 extent that examination often fails to reveal the presence of fecal bac- 

 teria in 1 c. c. samples. 



Below Conimicut Point, in the broader expanse of the lower river, 

 five stations were located over the extensive Rocky Point oyster 

 ground. These were situated as follows: Station 1, over the northern 

 portion of these grounds, 6 miles below Fields Point; station 2, about 

 half a mile farther south, near channel buoy No. 9; station 3, just 

 north of Rock}' Point; station 4, south of Rock}^ Point; and station 

 5, over the southern areas of this ground, which is about 8^ miles south 

 of the Fields Point sewer outlet. 



A single trip was made to the Warren River in October, 1902, and 

 samples collected at five stations about half a mile apart. Station 1 was 

 located at buoy No. 1, marking the entrance to Warren River channel, 

 w^hich is in reality in the Providence River, about half a mile directly 

 south of Rumstick Neck; station 2 directl}^ in the entrance to the 

 Warren River, half a mile above station 1, and so on up the river. At 

 this time samples were collected at a station, No. 6, in Providence 

 River, located at buoy No. 7. These samples were taken because this 

 locality is sw^ept by any tidal currents that may come from the Warren 

 River on ebb tide, and it v^as desired to ascertain whether pollution 

 from this stream was noticeable in the Providence River at that point. 

 Tables V and VI give in condensed form the results of the analysis. 



