48 W. H. WARREN. 
coastal rivers sailing vessels have to pass, the leaf type of lifting 
bridge with a clear opening of forty feet is adopted, in which the 
lifting span is hinged at one end and raised by means of chains 
passing over timber towers and connected to balance weights, so 
geared that one man can raise the spanin ten minutes. In rivers 
in the interior where traffic is carried on by means of steamers 
and barges, the opening span is raised by wire ropes passing over 
towers at the four corners. The clear width of opening is fifty 
feet, and the lift twenty-five feet above flood level. The lift span 
is of steel and is raised by machinery carried on the top of the 
towers ; one man is required, the lift taking five minutes. One 
hundred punts and ferries are under the control of the depart- 
ment, six of which are worked by steam. The latest addition is 
that for the Hunter River at Hexham, which on its trial trip 
gave a speed of seven and a half miles per hour. 
Sewerage.—The total length of sewers completed or in progress 
at the end of 1892 in connection with the sewerage of Sydney 
and its suburbs was 4835°47 chains, and of storm water channels 
95441 or a total Jength of seventy-two miles 29°88 chains. Of 
this length five miles 10°61 chains of sewers and three miles 20°55 
chains of storm water channels were completed during the year, 
while on the 3lst December, four miles 52:13 chains of sewers 
and four miles 7:29 chains of storm water channels were still in 
progress. Amongst the most important of the sewers completed 
was the extension of the George-street West sewer, through the 
Glebe to Annandale (with its branches) which will ultimately tap 
the whole of Leichhardt and Balmain. It is unfortunate that 
owing to the present depression it has been found impossible to 
proceed with the reticulation of this district, as if this could be 
done it would not only be a boon to the residents, but would 
render the trunk sewers already constructed, revenue producing. 
An extension of the Prince Alfred Hospital sewer through Cam- 
perdown to Liberty-street Newtown has also been completed. It is 
designed to drain Camperdown, and parts of Newtown and Peter- 
sham ; some portions of the latter areas have already been reticu- 
