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which has a tendency to set over the south
part of the Treachery and South Head
Shoals.

Note.—The South Head Beacons are
placed on sliding ways for moving, so as to
be adjusted to lead the channel course as
circumstances may require in cases of the
shoals shifting, and if required the beacons
can be used as lighthouses.

Main Channel.

The present directions for crossing the
bar are to get the signal mast on the South
Head to bear E. by N. ½ N. (magnetic) on
the Ninepin Rock, in line with the tangent
of the inner point of the South Head, as
shown on the chart and sketch by Commander Sydney, R.N., in 1860. This course will
lead a fair way over the bar, carrying three
and a half fathoms at low water. After
crossing the bar, a glance at the chart will
be sufficient to keep the channel. To cross
the bar at low water is not advisable unless
the water be very smooth, with a commanding breeze or steam. As a rule, it will be
better to wait for half-flood or near high-water, and after having crossed the bar, and
arrived to eight or nine fathoms water in the
vicinity of the Orpheus Shoal, it will be
necessary to steer along the line of break in
the middle banks, distance about one quarter
of a mile, which will clear and leave the
Orwell Shoal on the porthand. From this,
towards Paratutai, the channel leads straight
into the harbour. The main channel is
seldom used since the South Channel has
been buoyed and beaconed, and the Signal
Station removed from the North to the South
Head, where the site is less obstructed by
back land. The Southern Channel, in general, is preferred, in consequence of being
more sheltered and accessible at times when
the main bar is dangerous.

Note.—The flood comes from the northward, setting along the shore from one to
two knots; but when coming in contact with
the banks about the bar, it trends into the
channel increasing its rate to four or five
knots as it approaches the Heads.

Care should be taken to guard against the
cross tides about the spits, and swatchways
when near them; but in the middle of the
main channel the tides set fair in and out
of the harbour.

The prevailing winds are from N.W. to
S.W.; it seldom blows a gale from the southward, the wind moderating as it draws from
S.W. to southward. Easterly gales are not
frequent, and generally shift suddenly to the
westward, in a violent squall, and bring heavy
rain. The gales rarely continue long in one
quarter, and a strong breeze from N.W., or
even W.S.W., as a rule, does not cause a
heavy sea in the South Channel, which can
be taken with safety towards high water.
The bar, with such winds, generally speaking,
breaks, and sometimes dangerously, towards
low water; but, in case the gale gets to the
S.W., the sea will break right across both
channels, but less across the South Channel,
which is never at any time so dangerous as
the main. This, however, is of short dura-
tion, and seldom lasts over a day and night,
when by the morning it becomes moderate,
and the South Channel free of break, (even
though there is considerable swell outside
and the banks breaking heavily) and safe to
enter at proper time of tide, say half flood,
or even at first quarter ebb, with a com-
manding breeze or steam.

Barometer.

A falling barometer generally indicates a
change to a northerly quarter, to be shortly
attended with rain; and, in case the
barometer begins to rise, expect wind.
When the barometer is ranging about 30in.
steady weather may be expected from the
westward; a high barometer, say above 31
inches, and the land appearing very clear
and nearer than usual, is, (as a rule,) a sign
of a change to the eastward. On the coast
of New Zealand, for many years past, I have
observed that very clear and cloudless nights
are indications of a change being at hand,
either wind or rain.

T. W.