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Q. 4.-What are the usual indications of a ship being on
the line of progression of the centre of a cyclone ? A.—The customary signs of an approaching cyclone
as regards barometer, sea, and sky, but no change in the direction of the wind until the centre has passed, when it will blow steadily from the opposite
quarter. Q. 5.—What are the usual indications that a ship is (u)
approaching the centre of a cyclone; (b) receding
from it? A.—a) Barometer falling: sea getting up. Threaten
ing appearance of the weather. Dense cloud-bank. Gale rapidly increasing in violence, with terrific squalls quickly following each other. Wind changing, (except she is on line of progression) and sea becoming cross and dangerous. (6) Barometer rising. Wind abating and sky clearing, but
sea still confused and dangerous. Q. 6.—Describe the track usually taken by cyclones in
the Bay of Bengal, and state the seasons of the year in which they most frequently occur in that
region. A.-In this region storms take different tracks, those
in the lower parts of the Bay going to the westward, while in the upper portion they generally travel N.N.W. The seasons are at the change of Monsoons; April, May; Sept, Oct., also in Nov., the
two latter being worst months. 1.-N. Hemisphere. 8 points to right. 2:—Wind hauling to right, ship in right hand side.
Look at No. 6, average track N.N.W., but change of wind shews going North; corresponding diagram will shew ship as almost out of dangerous quadrant. By sailing as directed she will improve the weather, and perhaps get a fair wind for Calcutta, only watching the storm does not recurve to N.E.
Q. 1.—The direction of the wind in a cyclone being
West, state the probable bearing of its centre
from the ship in the Northern Hemisphere. A.- About North.
Q. 2.-And suppose that the wind during the passage of
the same cyclone were found to change toward the S.W., what would be the ship's position with reference to the line of progression of the centre of the cyclone; and what action would you take ?
A.-The ship would be in the left
hand side of the line of progression. I would run her with the wind on the starboard quarter until in a safe position, and then, if necessary, heave her to on the port tack. I would expect here to find a heavy
Q. 6.—Describe the track usually taken by cyclones in
the China Sea; and state the seasons of the year
in which they most frequently occur in that region ? A.-In this region storms generally travel W.S.W. or
W.N.W., towards the Chinese coast. They occur between July and November, September and October being worst months.
2-Ship is in the S. E. part of the typhoon, and in a hinder quadrant. She should be kept well out to the S.E. to avoid the terrible sea of the wake.
The rules and examples given should be sufficient for the purpose intended, but in order to add to the completeness of the work, the subjoined extract from the official “ Barometer Manual” is appended. It comprises rules for a ship which has been lying-to, awaiting the development of a tropical cyclone, whether to remain so or not, and for the tack on which to put her when her place in the storm has been ascertained.
“N. hemisphere. If in the right-hand semicircle, heave-to on the starboard tack. If in the left-hand semicircle, run, keeping the wind, if possible, on the starboard quarter ; and when the barometer rises, if necessary to keep the ship from going too far from the proper course, heave-to on the port tack.
S. hemisphere. If in the right-hand semicircle, run, keeping the wind, if possible, on the port quarter, and when the barometer rises, if necessary to keep the ship from going too far from the proper course, heave-to on the starboard tack. If in the left-hand semi circle, heave-to on the port tack.
Both hemispheres.--- When the ship lies in the direct line of advance of the storm * * * the most dangerous of all-run. And in all cases act so as to increase as soon as possible the distance from the centre; bearing in mind that the whole storm field is advancing."
The above is from the latest and most authoritative work on the subject (issued after this was in the press), and is designed to suit either circular, spiral, or incurving storms. It will be noticed that the only difference between these rules and those given by the writer are, that where the “ Manual” calls a whole semicircle dangerous, the “Catechism” so terms only a quadrant; also that where the former recommends at once heavingto in the dangerous side, the latter advises trying to increase the distance from the centre prior to doing so. It is very satisfactory to the writer to thus find his precepts corroborated by such high authority.