340 Til AN S ACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



the Local Sanitary Authorities have not yet attempted to 

 realise. In 1898 Mr. H. Bertram Nichols, C.E., designed 

 the present system of sewerage. At that time the 

 Cameron method of septic purification was in high favour, 

 and it was decided to adopt this. The scheme provided 

 for the collection and treatment of the sewage (almost 

 entirely domestic) of Morecambe, Bare and Torrisholme — 

 an estimated population of 11,000, with an annual influx 

 of 30,000 visitors — at an estimated total cost of £60,000. 

 Really the system was designed to cope with a population 

 of 60,000 persons, and for an average daily water supply 

 of 20 gallons per head. The main sewers are laid along 

 the back of the town, and terminate in two main outfalls, 

 iron pipes of 21-inch and 24-inch diameter respectively. 

 These open into two culverts, which are designed to 

 contain an aggregate night flow of 400,000 gallons. The 

 culverts open into a well, and the sewage, after being 

 screened so as to remove solid matters, is raised by means 

 of four centrifugal pumps worked by electric power to 

 the level of the channels leading into the septic tanks. 



There are eight rectangular tanks, each of which is 

 covered in and airtight. After passing through a 

 " detritus chamber," in which much of the grit from road 

 washings is allowed to settle, the sewage passes through 

 special inlet pipes into the tanks themselves. Here it 

 is allowed to remain, and the well-known septic 

 process of purification goes on. The saprophytic 

 and nitrifying bacteria normally present in the 

 stale sewage act on the organic matters present, 

 and most of the solids present in suspension pass 

 into a state of solution. Organic matter is broken down 

 and resolved largely into harmless nitrites and nitrates. 

 A certain amount of sludge settles at the bottom of the 

 septic tanks, but the rate of accumulation of this is very 



