SEA-FISHERIES LABORATORY. 485 



The Lancaster sewers are about five miles above the 

 Bazil Point mussels. There is a small sewer about half 

 a mile distant, and a fairly large one about 2\ miles 

 distant. The contamination of the mussels is not, then, 

 nearly so immediate as in the case of the Conway beds. 

 At the time of high water, the dilution of the sewage will 

 be as above, but as the tide ebbs this dilution will 

 decrease. At low water the width of the Estuary is 

 represented by the lines indicating the level at low water 

 of ordinary tides, and the volume of water is now very 

 much less, but the sewers still continue to discharge. At 

 low water, Crook Skear dries, but there will still be 

 mussels on the Bazil Point training wall which are 

 bathed by the ebb tide. Now, considering these 

 conditions, it does not appear that the liability of the 

 shell-fish to dangerous contamination will be so great as 

 in the Estuary of the Conway. 



On the other hand, the bacteriological results 

 indicate a higher degree of sewage pollution. The recent 

 analysis quoted on p. 478 show 3,700 and 6,500 sewage 

 bacteria per mussel. This is, of course, evident merely 

 from a consideration of the number of sewers and the 

 number of the population served by each. 



But again, the epidemiological evidence is not at all 

 strong, in spite of this relatively high degree of bacterio- 

 logical impurity. Practically the evidence that I know 

 of was summarised by Dr. Bulstrode on p. 225 of his 

 Report (Shell-fish other than Oysters), and it cannot be 

 contended that this is convincing enough to establish a 

 thoroughly good case for condemnation. 



We must recognise, however, that the Estuary of the 

 Lime is thoroughly fouled by sewage matters. Naked 

 eye indications of this may easily be seen in the river 

 itself in the vicinity of the outfalls, on the banks aa 



