SEA-FISHERIES LABORATORY. 489 



contamination of the mussel beds. What we have to 

 consider is not so much the production of a non-putrefiable 

 effluent as an effluent free from intestinal bacteria, and 

 it does not appear that this is likely to be effected by any 

 system of sewage purification at present in use. Still if 

 such system of treatment as is in use at Morecambe 

 succeeds in breaking up solid faecal matter and producing 

 an uniform effluent in which there are no coarse particles 

 of sewage matter, much would be gained, for a more 

 uniform and speedy distribution of the effluent with the 

 diluting sea-water would be effected. On the only two 

 occasions on which I saw this effluent being discharged 

 there was indeed no solid faecal matter visible, but the 

 effluent itself was a dark, turbid liquid. There were 

 some flocks of gulls on the surface of the water, and this 

 may have indicated the presence of solids which I did 

 not see. Dr. Bulstrode, in his last report, refers to the 

 effluent as a " thick black liquid, containing numerous 

 small pieces of paper, and some small faecal masses, 

 and the discoloration of the water thereby was to be seen 

 for considerable distances round the outfall." We have 

 therefore no assurance that this septic tank installation 

 is being worked in the manner that its designers 

 intended. We cannot, of course, assume that it will 

 always be properly worked. This does not matter so 

 much with regard to the outer Heysham mussel skears, 

 but it is a consideration of some importance with regard 

 to the upper mussel grounds. 



The conclusion, then, is that the mussels taken from 

 the Heysham Skears are quite suitable articles of human 

 food, and that there is no dangerous contamination ; but 

 that until the improvements suggested by Dr. Bulstrode 

 are carried out, it would be as well to regard the mussels 

 from the upper skears — Editing Knot, Stone Skear, Little 

 Skear, and Bare, as undesirably contaminated. 



