188 JOURNAL OF SCIENCE. 
Pacific. It flows through one of the most productive districts of 
New South Wales; and from the wonderful richness of the soil, 
there can be little doubt that this district is destined to play an 
important part in the development of the great agricultural] re- 
sources of this colony. But for the existence of the bar at the 
entrance of this great natural means of internal communication 
Gratton the Clarence district would, there is little reason to doubt, 
be next in importance to Sydney herselt, for with the entrance 
once secured the port would be the natural outlet for the trade, 
not only from the immediate district itself, but from the whole of 
the country stretching away to the table-lands of New England 
and beyond. The pressing necessity, therefore, of removing this 
obstruction to the progress of this important part of the colony 
cannot be over-estimated. In examining this case the same con- 
tending forces are seen at work—namely, the struggle between 
waves and tide, the result being that the entrance has been driven 
into amost awkward corner by the action ot the north-east winds, 
the river being diverted from its straight course into one of the 
most ugly bends imaginable, with the result that, instead of a good 
channel, we see a succession of deep-holes and sandbanks, and to 
make matters worse there are several dangerous sunken rocks in 
this already uninviting entrance. Nature has done much towards 
the removal of this most unsatisfactory state of things, the entrance 
being well protected on the south by the South Head; moreover, 
an enormous volume of tidal water is available, only wanting skil- 
ful directing in order that it may become a most powerful agent, 
and one that would be more than equal to the task of removing all 
obstructions. Wanting such directing, this great natural power is 
expended in dredging deep holes in places where they are not re- 
quired, and heaping up sandbanks on the site of the much-desired 
entrance ; at the same time, on account of the frequent changes 
of direction, troublesome eddies are formed to further increase the 
difficulties of navigation. There should be no great difficulty in 
fixing the entrance and removing the bar, considering that nature 
has provided perfect protection on the south side; allthat appears 
necessary is the construction of a breakwater to protect the en- 
trance from the north and south-easterly weather. At the same 
time the channel should be straightened by cutting through the 
spit, and deflecting the stream trom the south side of the river by 
the construction of a dyke from the south bank to Rabbit Island, 
extending a short distance into the main channel. The break- 
water once constructed, the removal of the spit would be an easy 
matter; for by cutting a narrow canal parallel with Queen street, 
Huka, the tide would soon complete the work of cutting a good 
channel. The new channel being straight, the banks would more- 
over require but little protection, as they would not be subjected 
to the excavating action inseparable from curved channels. The 
advantages of this plan of treatment must be commendable to the 
most casual observer. Firstly, the entrance being protected on 
the south side by the South Head and on the north by the break- 
water, extending into deep water, the protection from the waves 
is complete. Moreover, the channel being straightened, the tidal 
and upland waters, unimpaired by any abrupt changes of direction, 
would do the work of maintaining and improving the channel, and 
at the same time keeping the entrance clear of all obstructions. 
