[2] 
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Fourth. On the extent and form of the hreak water. 
1st. As to the complete harbor at the position B. 
Going far enough from the shore to leave about half a mile in 
breadth, of good anchorage, vvc di-aw the line b c^ oi 740 yards. 
The direction of this line must be such, that the course of the ebb- 
tide will make, with it, a very oblique angle. From the western ex- 
tremity of this line, we draw the iine a b, (towards the shore,) at an 
angle of 135°, to which vve give a length of 440 yards; and from the 
eastern end, we diaw the line c (/, at the same angle, of 580 yard^ 
in length. It will be seen, by an inspection of the chart, that the ice 
which will strike a breakwater, made according to the above deline- 
ation, will be deflected outwardly, while that which passes within 
the extremity 6 will course along near the shore, leaving a broad 
space entirely clear. It will be seen too, that, while by the shore or 
the breakwater, all winds will be entirely excluded except the east- 
northeastwardly, that there will be a large space secuie even from 
these. The area of this harbor will be about half a mile square^ 
the mean depth at low water being 28 feet, the whole length of the 
breakwater will be one mile. The bases of the interior slopes of this 
work will he one half the altitudes: but the exterior, being exposed to 
a heavy sea, will require for the slopes bases of four times the alti- 
tudes. The side facing the northeast will be finished at high water 
mark, while the other two sides must be raised three feet higher, to 
keep the ice from being forced over into the liarboi'. 
£d. As to the partial breakwater at the position A. 
From the point c, which is in about 12 feet water, we draw the line 
e/, of 1,100 feet, so as to form with the course of the tide an angle 
of 120°. This line is so far up the roadstead, that a vessel aiichoi'ed 
behind it at the distance of 800 yards, will be protected fiom E.S.E. 
winds by the lower part of the shears ; and here it is proper to re- 
mark, that the winds blowing from between E.S.E. and S.E. are 
neither violent nor of long continuance. It will be perceived on the 
chart, that, from the direction we have given to the breakwater, the 
descending ice will be deflected towards the deepest water and strong- 
est current, and that vessels, to the number of twelve, moored in two 
lines behind the breakwater, will be protected either by the shoal or 
by the main land, from all winds, excepting those just mentioned. 
it has frequently been remarked above, that tlie shoal itself is a 
good breakwater, and there is no doubt that vessels, provided with 
good ground tackle, could ride under its lee in safety; but it is proper 
to provide against deficiency in this respect, which may be often ex- 
pected with merchant vessels; tlierefore, the Commission propose to 
fix, in addition to the breakwater, two lines of heavy anchors, con- 
nected with buoys, by strong chain cables. These buoys, cables, 
and anchors, will not only enable vessels to ride in safety, but the 
buoys will guide the vessels as they arrive at their proper stations in 
the harbor, thereby ensuring the greatest economy of space. The 
Jength of the line of breakwater is just sutlicient to cover the vessels 
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