COLLECTION AND TREATMENT OF SEWAGE. 687 



The author took advantage while in Europe to visit Trouville, 

 in France, where the vacuum (pix)perly known as the " Liernur ") 

 system has been in constant use for thirteen years, and, thanks to 

 the courtesy of the municipal authorities, he was enabled to 

 thoroughly investigate the whole systen:i. 



The main works are situated on tlie outskirts of the city, which 

 has a poi^ulation varying from 12,000 in the off season to 38,000 

 when the season is at its height. 



The whole staff at the works consists of three men — one 

 engineer, one fireman, and one turncock. In the engine-house are 

 two vacuum pumps that exhaust the air from the district and main 

 receivers, and discharge this foul air, which would be most offensive, 

 into the furnaces, and so supplies the necessary draft for the fires, 

 And is rendered free from smell. 



The turncock goes round the district receivers and opens in turn 

 the mains leading from the different streets, and as he opens the 

 various valves the sewage is sucked from the houses into the receivers 

 at the rate of 12 ft. per second. No extra water is used for flushing 

 the pipes, which are found to keep perfectly clean after years of use. 

 No foul gases can find their way into the houses, in fact, air is 

 drawn from the houses into the system, and this is regulated by :i 

 most ingenious and simple contrivance. 



The amount of sewage dealt wdth varies considerably, but in 

 European cities may be taken at 10 to 18 gallons per head per diem. 

 The installation at Amsterdam was put in in 1870, and serves 

 a population of 230,000. 



The Trouville system was installed in 1896, and serves, as 

 already stated, from 12,000 to 38,000 people. 



A number of small installations exist on the continent of 

 Europe, and in South Africa, and one in Great Britain in the small 

 town of Stanstead, Essex. 



The cost of installing the vacuum system at Stanstead was £3 

 per head for 750 persons; at Trouville (originally) £1 per head for 

 12,000 persons. 



An estimated cost prepared some years ago for Maitland, New 

 South Wales, was about £3 per head, the difference in cost being 

 due, no doubt, to the extx'a cost of labour and material in Australia. 



The cost of a water carriage installation, without pumping (as 

 in Sydney), ranges from £8 to £10 per head, but the main objection 

 to this system is the tremendous cost to property-holders, who have 

 not only to fit up their buildings but to connect them with the 

 sewers, which are often many feet down in the ground. In Melbourne 

 some property-owners found the cost of connection almost ruinous, 

 although quite a number of years were given to pay it in. 



With regard to the cost of operating the vacuum system at 

 Stanstead the recorded cost is Is. per head. At Trouville the proved 

 cost is 3id. per head on 12,000 population, and naturally less for 

 38,000. 



As regards the health aspect of this system, Amsterdam supplies 

 some interesting figures. Taking the thirty years during which this 

 system has been installed, from 1871 to 1901, the mortaHty has de- 

 creased more than 50 per cent. Now, while it may not be fair to 

 credit any one system with all the decrease in the death rate, yet 



