28 ON THE REMOVAL OF BARS FROM 
same state as our principal rivers are at present, namely, nearly 
blocked by a shifting sand-bar, with deep water on either side. 
transformation has been made in this entrance by the carrying out 
of judiciously planned works. By the construction of the two 
same time the tidal scour has been greatly improved by reason of 
the large area enclosed by the breakwaters. The foreshore has 
only slightly advanced, and from the rapidly increasing depth sea- 
ward there is little danger of any serious trouble from this cause. 
south breakwater, a considerable improvement has already taken 
place, the bar having been lowered several feet. 
plans were suggested early in the present century for further 
improving the entrance, and if possible for the removal of the bar. 
Eventually it was decided to construct the great north wall, start- 
ing some distance up the coast and converging towards the end of 
the great south wall, thus enclosing a great tidal area for scouring 
purposes, at the same time forming, with the south wall, a sort of 
nozzle, directing and concentrating the action of the tide on the 
bar, and likewise protecting the inside harbour from the waves. 
the entrance, they have been designed so as to make the best 
E ible use of the available scouring power, and their success 
is established by the fact that the bar ha: 
