SAILING DIRECTIONS FOR THE MANUKAU HARBOUR.

Southland Times, Volume III, Issue 45, 19 February 1864, Page 7

SAILING DIRECTIONS FOR THE MANUKAU HARBOUR.

JtTSI COMPIET-RD BY CoMMAHDEB IV W. * Sidney, R.N: , In consequence of the changes that have taken place in the approaches to tbe Manukau Harbor (as so deplorably manifested by the loss of H.M.S. Orpheus), the Admiralty determined to have a new survey made, and directed Captain Sidney, R.N., to suspend for a time the survey ofthe coast of New South Wales, upon which he was engaged, and proceed to New Zealand to re-survey and draw up fresh sailing directions for the navigation of the channels leading to the Manukau: _j The following remarks and directions result from the re-examination of thafc locality :— The entrance to the main channel appears to have shifted both to the northward as to seaward, the bar now being half a. mile more to; the westward than at the time of Captain Drury's survey in 1853. The channal is also wider, the 8-feet bank that separated what was called the Norfch Channel from the main , haying now disappeared, if ifc ever existed. Aship, by attention to the lead, may now work either in or out. ■■'■*• •- The leading mark used at present is ; the Nine Pin rock, in line with the tangent of the inner point of the South Head, as shown in the sketch ; but as there is the same'' depth, viz.— 3^ fathoms a little th the norths ard, and the banks having a tendency to extend- themselves yet more in that direction, tt would be better to bring the Nine Pin Rock in line either wifch the objects marked B or C on the sketch and plans for crossing the bar. After crossing the bar a glance afc the plan will be sufficient to keep the channel. The South Channel stems hitherto to have' been very imperfectly known, and its merits underrated ; but now thafc buoys have been placed, its approach and navigation is rendered easy, and the depth of water being the samo as that on the bar of the main channel, and accessible at times when the latter is dangerous, it is much to be preferred,' To make the South Channel from seaward, keep fche signal staff of Parafcutai in line with the White Pile recently erected on the inner slope of the peak called Pukehuuhu on the chart (properly Pnkehoho), N. £W. This mark leads midway between the shoals off the South Head and the Heron Spit ; and when tho gap inside Poroporo (now almost an islet) and the Two Trees, to the righb of tbe wooded range, como in line, steer for ifc up to fclie outer Fairway Bnoy, tbe crossing mark for which is the Nine Pin rock and Parera Island in lino. The outer Fair-way Buoy is red, with black vertical stripes, having a bell within a circular cage on top. Leave this buoy, or the spot indicated by the marks, on the left hand half of a cable, steering 1-J- point more to the east for nearly four cables' length, when the inner Fairway Buoy will be reached. This buoy is similar to the outer one in every respect. Leaving this also on the left hand half a cable's length, two buoys will be seen in advance to the northward — a black one on tho left indicating the position of the Tranmere Shonl (to the westward), and a red one on the right.lf cable apart — pass midway betweon them steering parallel with the shore, passing the Soifc Buoy (red) on the right, nnd the buoy afc the tail of the Emma Bank (half black and white top) on the left, iuto the deep water channel. Ifc is recommended thafc Pukehoho be chosen as the site for the contemplated telegraph station ; the signals to be made by two pairs of semaphore arms — one pair above the other ; one half of the arms along their lengfeh being painted black and fche other white, which would ensure their been seen under all circumstances of light and shade, against the sky, or with tho, land behind — the arms working afc right angles to a line midway between the main and south channels. The stump of fcho mast or a beacon should bo on Parafcutai for the South Channel entrance mark. The following remarks are by Mr. Wing, pilot and harbour-master, made during an experience of over a quarfcrr of a century : — High water at the entrance of the Manukau at fnll and change of moon afc 9h. 30m. The rango at springs, 13 feet ; neaps. Bfe -t. The flood comes frcm the northward, setting along the shore from one to two knots, bufc when coming in contact with the banks aboufc tho bar, it trends into the channels, increasing its rate to four or live knots as it approaches the Heads. Care should be taken to guard against the crosstides about the spits and swatchways. The prevailing winds are from N.W. to S.W., and ifc seldom blows a gale from the southward — the wiud moderating as ifc draws from S.W. to southward. Easterly gales aro nofc frequent, and generally shift suddenly to the westward, in a violent squall and very heavy rain. The gales rarely continuo long in one quarter, and a strong breeze from N.W. or even W.S.W. (as a rule) does nofc 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 ; bufc in case the gale gets to the SW., the sea will break right across both channels bufc jess across the S channel, which is never afc any time so dangerous as the main. This, however, is of short duration, and seldom lasts over a day and night, when by the morning it becomes moderate, and the south' channel free of break (even though thero be considerable swell outside and the banks breaking heavily), and safe to enter at proper time of tide, say afc half flood, or even at first quarter ebb, wifch a commanding breeze or steam. Babometek. A low range denotes a change, and in a northerly quarter to be shortly attended by rain ; and in case the barometer begin to rise, expect wind. When the barometer is ranging aboufc 30 inches, steady weather may be expected from seaward. A high barometer — say above 31 inches, and fche land be looming clear and distinct, it is, (as a rule) a sign of a change to the eastward. Ihave also to remark that for many jears I have observed that very clear and cloudless nights are indications of a chadge being afc hand, either wind or rain. Frederick W. Sidset, Commander and Surveyor. December 21st, 1863. Saiiing- Dihections pok Waikato Eivee. When near the Waikato, do nofc shut in Oruaranghi Point (a point 3 minutes southward of fche entrance) until the fairway beacons are in one, bearing N.E. by E. \ E easterly (magnetic) ; then proceed over the bar, with them in line. When jusfc over the bar, the water will deepen 5 or 6 feefc ; keep fche marks on until a sandy cliff on the South Head is aboufc to shut in, then steer for Putataea. When the Mission House is touching a yellow cliff on the west side of Putataka, see that the small black beacons are still open, to avoid the five-foot bank to northward of channel. If wishing to bring up fco the eastward of Putataka. anchor so as to swing clear of a four feefc rockj E- by N., one cable from the point, and the shoal water to the northward of the Channel. If a vessel is 150 feet long, she must moor, bufc can lie at single anchor to the ]S r .W. of the point. The tide is less to the eastward of the point. In going out from Putataka, steer down for the mouth of the river, keeping the black beacons open to avoid the 5-^feefc bank. Bring the Fairway Beacons in line when the_ Sandy "cliff is about to open itself, and proceed" across the bar. Keep the marks on until Oruaranghi Point is well open, when you are clear of the breakers afc the entrance. Tho least water on the bar wifch the Fairway Beacons in line is 12 feefc . 6 inches, afc low_ water spring tides ; bufc there is 10 feet a short distance to the northward, and 11 feet the same to the southward, so that the marks should not be opened much. The beacons when in line are in the middle of an easily recognised gully. The eastern beacon is on White shell summit. The western the 4-mile S.W. by W.JW. from ifc on a little mound. The Spits at the entrance appear to have shifted since Captain Drury surveyed the Waikato, as the present fairway njagnetie bearing differs 4 degrees or nearfcy half §. point from, the old one. Jons: G. Botjlton, R.N., Master's Assistant and Assistant-Surveyor.