PUMPING MACHINERY OF THE WATER AND SEWERAGE BOARD. XLIII. 



Battersea. If such had been the case, and it had also been 

 possible to remodel the old Botany engines, converting 

 them to triple expansion, then possibly an efficiency at 

 least double of the average now reached in our Sydney 

 sewage pumping might have been attained. It is rather a 

 pity that the author left out all reference to the Farcot 

 (French) type of pumping engine, which is very economical 

 in first cost, owing to the high piston speeds possible; in 

 fact there are records up to 500 feet per minute, and the 

 Botany temporary pump designed by him and made by the 

 Atlas Engineering Co., was run up to 360 f.p.m. quite 

 smoothly. The author's figures for the old Botany engines 

 appear to be much too favourable, they were reported upon 

 by him (the speaker) in 1880, and found then to give an 

 average duty of only 24*07 millions. Of course that is 

 assuming that all the coal paid for was utilised by them. 

 At the same time the locally made Crown Street engines 

 were more than twice as efficient with a duty of 62 millions. 

 Unfortunately the records of the Farcot locally made 

 temporary engines at Botany were hurriedly taken, but 

 they showed about twice the efficiency — although non- 

 condensing — as the permanent condensing engines did. 

 This was largely due of course to the higher pressure of 

 steam and the expansion of same in a compound engine 

 giving a very mild exhaust to the atmosphere. 



The diagram given by the author illustrating the water 

 supply of Sydney, and the percentage of "gravitation" and 

 " pumped" water is very interesting, because it shows the 

 futility of going abroad for advice from an engineer 

 altogether unacquainted with the country, when there are 

 plenty of local engineers better seized with local conditions. 

 Although one million gallons a day was raised to Paddington 

 in 1876, Mr. Clarke, in his report on the City Water Supply 

 only allowed for Crown Street station pumping 1J million 



