tides. The impression one gets here is that the mvissels are 

 clean and well scoured. There is neither smell nor mud, and 

 they are evenly distributed on the shingle and stones forming 

 the top of the wall. The main sources of pollution of these 

 mussels would be the effluent from the Preston Sewage Farm 

 at Freckleton, between the third and fifth miles on the 

 northern side of the Channel. The only treatment this 

 sewage gets is coarse screening, sedimentation and irrigation 

 on the Sewage Farm ; it is simply sewage with the coarser 

 matter removed. This effluent is run off into the Channel, 

 and has to flow about nine miles before reaching the mussels 

 under consideration, and it is probable that the dilution must 

 largely reduce the risk of serious pollution. Another probable 

 source of pollution was evident in the effluent from the Lytham 

 East sewer. This drains down a mud gutter, and empties 

 into the channel about 70 yards in front of the Pier at dead 

 low water. This is about the ninth mile, or four-and-a-half 

 miles away from the mussels under consideration. The 

 volume of effluent is small, and it has four-and-a-half miles 

 to travel down channel before it reaches the mussels ; the 

 risk of pollution is not serious. A very important source of 

 pollution is the effluent from the Ansdell and Lytham outfalls 

 referred to as probably polluting Church Scar Bed. This 

 finds its way into the Channel, and must be included as one 

 of the sources of pollution of the latter. It appears to find 

 its way into the Channel above the 13.1 mile point, probably 

 somewhere about the 10^ mile point, in its most concentrated 

 condition at low water. 



Methods of Bacteriological Examination. 



Two samples were collected in the early morning of 

 November 3rd, 1921 , from the resjoective areas, packed in sterile 

 air-tight tins, and brought to Liverpool immediately after 

 collection. The Church Scar sample was examined the same 



