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In the right-hand semicircle, storm moving S.E.ward (or after recurving), wind hauls against the sun, hence from N.E.-ward through East and S.E. to South.

In the left-hand semicircle, storm moving S.W.ward, the wind hauls with the apparent course of the sun, hence from S.E.-ward through East to N.E.

In the left-hand semicircle, storm moving Mil.ward, wind hauls with the sun, hence from North and N.W. to West.

In either hemisphere, and near the tropic, if the wind hangs from the Eastward, suspect the storm as about to

recurve.

On the Use of the Barometer in a Cyclone.—It was long ago remarked by Piddington, that "he who watches his barometer, watches his ship." This invaluable instrument invariably announces the approach of a storm,—shows whether the vessel is plunging into or receding from it; and hence, by carefully noticing its indications, the disastrous consequences of a hurricane may, to a great extent, be avoided—for the laws of its oscillations are very distinctly marked. Between the tropics its oscillations are so regular that any sudden fall of the instrument indicates the approach of a hurricane, even though all atmospheric and oceanic appearances of its proximity are at first absent. Beyond the tropics, the oscillations are incessant and irregular, but a continuous fall of the instrument, with a wind increasing in force, indicates that you are already in a cyclonic area. The barometer often stands unusually high before the commencement of a cyclone, and frequently (if not always) just around the storm; and conceiving the cyclone to be divided

into two parts by a diameter at right-angles to its path, it may be noted that in both hemispheres—

The barometer always falls during the passage of the advancing semicircle of a storm; and—

Always rises during the passage of the receding semicircle of a storm.

If purposing to take advantage of the winds and to keep just within the verge of the storm, the barometer is of signal benefit,—it should be kept as high as possible without losing the wind. In whatever position the ship may be, the rising of the mercury announces that the first (or dangerous) half of the storm has passed.

Hurricane and Storm Seasons.—In tropical regions and on their borders hurricanes occur only at certain seasons of the year; they are periodical; one or more may occur in the season, on rare occasions none. extra-tropical regions and in high latitudes cyclonic storms have no special period; but may occur in any month.

In

The West Indian hurricane season is July, August, September, and October.

The Mauritius hurricane season lasts from November to May, both months inclusive.

In the Bay of Bengal cyclones occur at, and are more or less connected with, the change of the monsoons; hence in May and June, and again in October and November.

In the China Sea, and off the south coast of Japan, typhoons are experienced from July to November, both months inclusive.

Among the South Pacific Islands the hurricane season is January, February, and March.

In the tropical part of the South Atlantic hurricanes unknown.

In the Northern part of the North Atlantic and North Pacific, and also in the Southern part of the South Atlantic, South Pacific, and Southern Indian Ocean, these storms may occur at any part of the year.

Tack on which to heave-to.—In the Northern hemisphere, in either semicircle of the storm, if the ship is hove-to on the starboard tack, her head is directed from the centre, but if on the port tack towards the centre. In the Southern hemisphere, it is when hoveto on the port tack that the ship's head is directed from the centre,—on the starboard tack towards the centre. This is a necessary consequence of the rotation of the wind in the two different hemispheres; and it might seem that the starboard tack would be the proper one for the northern hemisphere, and the port tack for the southern hemisphere, in both semicircles of the storm alike. But there is always the danger of getting sternway when the wind veers by the head; hence, if obliged to heave-to, since it is advisable to put the ship on the tack on which she will come up as the wind shifts, the Rule for both hemispheres is:

When in the right-hand semicircle heave-to on the starboard tack.

When in the left-hand semicircle heave-to on the port tack.

Running before the Wind.—It is recommended, as a rule, not to run before the wind in a hurricane: should it however be necessary, due regard should be had to the indraught of the wind; hence to avoid closing with the centre, you must if possible—

Keep the wind well on the starboard quarter in the
Northern hemisphere; but—

Keep the wind well on the port quarter in the
Southern hemisphere.

In extremely heavy gales there is, of course, danger of broaching-to if the wind be brought on the quarter, so that these instructions can only be followed before the wind becomes too strong.

The following figure is intended to show what would be the track of a ship in the northern hemisphere,

when steered so as to keep the wind on the starboard quarter. The reverse of this figure (which may be obtained by holding the leaf up to the light with its back turned to the eye) will show what would be the track of a ship in the southern hemisphere, when steered so as to keep the wind on the port quarter. These figures represent the tracks of ships in whirlwinds supposed to be stationary. In gales having progressive movement such tracks would be modified. The best course to be steered so as to carry a ship away from the centre of a revolving storm may, after all, depend upon the direction of the swell and sea, as well as of the wind.

The following are Dove Rules, but they are only proximate, and may be referred to, cautiously.

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