WHARF CONSTRUCTION, SYDNEY HARBOUR. XXXI. 
years ago, has given me an exeeptionally good opportunity 
of closely observing the behaviour of the various classes 
of timber and other material used in their construction. 
It may have been noticed that timber for the construction 
of wharves and jetties still holds its own in Sydney, and it 
might be thought, seeing the extent to which iron and steel 
had displaced timber in ship building, that the same thing 
wouid have happened before this, in wharf construction. It 
might also be asked, if the wooden ship is obsolete, why not 
the wooden wharf also? In Hurope there is some point in 
this question, because suitable timber is scarce andit is being 
rapidly superseded by steel, by re-inforced concrete struc- 
tures, and by stone quay walls. In Sydney Harbour there 
are very few solid quay walls, the largest being the sea- 
wall at Darling Island and the privately owned wall at the 
Sydney Collieries, Balmain; there is also one of Monier 
sheet piling at the foot of Market Street. All the remain- 
ing public wharves having been constructed of timber. The 
reason for this preference for timber construction becomes 
evident as soon as the excellence of the material and the 
prime cost of construction are considered. In no other 
part of the world is to be found so plentiful a supply of 
good and suitable hardwood as in the forests of Australia. 
Owing to this fact, as long as the timber supply is available, 
wharf construction is more rapid, cheaper and more adapt- 
able than under any other system. 
During the iron age, that is before the present steel age, 
iron wharf construction was tried in Port Jackson. The 
iron wharf at the head of Darling Harbour erected by the 
Public Works Department in 1874, is a good example 
of this class. The high cost of construction and the very 
heavy cost of maintenance to protect it from corrosion, 
was however sufficient to prevent other wharves of similar 
design being constructed. 
