The China Sea directory - Sabrizain.org

CHAP. II.] BLAEA-Sn 'MATI ISliAND.^-TIBES. 107
just described. Between these two banks the depths are from 13 to 15
fathoms.
The soundings -south of Coney islet are deep but irregular; near the
reef which projects from it is a depth of 20 fathoms ;
south-westward from
Coney, depths of 18 to 22 fathoms extend to tlie distance of about 1^ miles
thence deepening to 40 or SO fathoms towards Long island.
At half a mile north-eastward of Helen Mar reef, is the western part of
a bank, which is about a mile in extent with 9 to 10 fathoms water. A
pateh of 9 -fathexms lieS half a mile northward of its eastern extreme.
A bank with depths under 20 fathoms, but irregular in contour, fronts
the whole -of the islands and dangers on the south side of the strait,
between Helen Mar reef, and Batu Beranti. Between Pulo Sannang and
the ledges west of Batu Beranti, the edge of this bank is about half a mile
from the shoal water near the reef extending from the north part of
Pulo Blakan Padang, and nearly three-quarters of a mile outside Pulo
Sannang.
TIDES.—The tidal stream from Malacca strait when setting to the
eastward, and the tidal stream from the China sea when setting to the
westward, meet between Tree island and Tanjong Bulus. It is high water,
full and change, at Coney island, at 11 a.m., but the tide does not set to
the eastward till about 1 p.m., and it is then about half ebb by the shore.
Between Tanjong Bulus and Tree island no dependence can be placed
upon the set of the tides, for they sometimes run strong towards Durian
strait, and at other times northward towards the Old strait of Singapore.
From Tree island to Raffles lighthouse the tides cannot be depended on
to set as fairly through the channel as they do to the eastward of the
lighthouse, but may be expected to draw more across the channel in a
north-easterly and opposite direction. The tides set fairly through the
channel about E.N.E. and W.S.W. between Raffles lighthouse and St.
John islands, frequently very strong, with eddies on the springs. Their
velocity, when strongest, is from 4 to 4| miles per hour, making it un-
pleasant to anchor here in large vessels when the weather is unsettled in
the night, particularly if unacquainted.
The tidal stream has been observed in both monsoons to run to the west-
ward 10 or 12 hours at a time, or even 18 hours, strong and weak
alternately ; at other times, it sets only 6 hours to the westward, and the
same length of time to the eastward. During the strength of the north-
east monsoon at neap tides, the stream sets to the westward at times for
three or four days, although there is a regular rise and fall by the shore.
Temporary anchorages.—Owing to the strong tides and cur-
rents in the western part of Singapore strait, sailing vessels are frequently
obliged to anchor, for which purpose the north side of the channel is to be