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would proceed, but more and more slowly as the deep water was 
approached till the current passing between the breakwater and 
it, was increased by the diminution of the channel, sufficiently to 
sweep away the sand as fast as the surf brought it forward, so 
that I conclude there would be an accumulation of sand on the 
beach to the Sd. of the breakwater, but from the example of the 
two shoals to the North, I feel satisfied that the passage between 
the end of the breakwater and the shore would never be closed. 
In the progress of things during the construction of the groynes, 
along the line of beach of late years, we have clear proof that the 
quantity of sand, in motion along the coast is not so very great, 
for since the number of groynes has been increased, extending as 
they now do for three miles along shore, the filling up between 
them with sand, has gone on very slowly, and it will probably be 
some years before the whole length of beach is extended much to 
seaward, though when there were only two or three groynes, the 
sand was deposited very rapidly. The only remaining effect that 
I believe the breakwater would produce on the line of the beach, 
is that somewhat to the Northward of the Nothern end, the beach 
would be cut away to some extent in consequence of the action of 
the surf upon it, while the sand removed by it, was not replaced 
by any surf under the lea of the breakwater, but this is of no im- 
portance. 
I am thus perfectly satisfied that a breakwater would not have 
any injurious effect whatever on the beach. 
^rd» Its cost. — The section which such a work will naturally 
take is now well known ; the inner slope is about an angle of 45® 
and the lower part of the outer one is the same. From a little 
above high water to a little above low water, the slope where the 
seas are excessively heavy is about 5 to 1, hence the cost of such 
a work very much depends upon the rise and fall of the tide. If 
this is great, both the work must necessarily be so much higher, 
and also the part on which the slope is so great must extend through 
a greater height, whereas in the present case, the rise being only 1 
yard, the cost will be greatly diminished, as compared with such 
works in England. Further I feel assured that the force of the 
