PUMPING MACHINERY OF THE WATER AND SEWERAGE BOARD. LI. 



which he believed was as low as that of any pumping engine 

 in the world doing the same amount of work. Latterly we 

 have had the Watt engine introduced at Ryde Pumping 

 Station, not altogether superseding the old pumps, but as 

 an improvement. These pumps however, did not maintain 

 the high reputation for duty in actual work which they 

 achieved at the trial; they nevertheless did very good 

 work. Then came the newer type of the turbo centrifugal 

 pump, and marked, he thought, the line of divergence in 

 one important particular between the pumping stations of 

 the past and those of the future — their economy of space. 

 One of these pumps raised water to a higher elevation than 

 any other south of the Line, or indeed, so far as his know- 

 ledge extended, in the world. So far these pumps had 

 worked well, but from an engineering standpoint, one 

 important factor had to be looked to, that was that the 

 ratepayers did not pay too much, and that the machinery 

 chosen for works of this nature should combine the maxi- 

 mum of efficiency with the minimum of cost so far as was 

 consistent. It would be absurd to give any opinion as to 

 the efficiency of these pumps after only one or two months 

 of running, because the only opportunity of testing them 

 had occurred when the reservoir at Wahroonga was empty. 

 With regard to the sewage pumps, Mr. Smail did not want 

 to say anything about the original engines, but he was very 

 glad to be able to say that the Board had adopted a sensible 

 view by simply taking them out and placing them on the 

 scrap heap ; that was all that could now be done with them, 

 although their workmanship was, he believed, unsurpassed 

 — it was the type and design of the pump that were at fault. 

 The next pump introduced was he thought the Gwynne. 

 Then Mr. Zollner came along with his own pump, which 

 appeared very well in the schedule, still experience had 

 proved many tilings about pumping machinery for that 

 gentleman to learn, especially in connection with the thrust. 



