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a supposition, that the hurricanes in the Bay of Bengal travel from the Eastward to the Westward,” and it may be quite safe to calculate upon their blowing in a circle from right to left. We must then assume this point, and supposing we have the wind at ESE. we are then somen'here upon the line leading from the NNE. point of the hurricane-circle to its centre. If the wind now veers to SE. and SSE, we can easily understand that the centre has passed somewhere to the Southward of us, and that we are upon the right hand side of its track. But if the wind had begun at North, and veered to the N. West and West we can also understand that the hurricane is passing somewhere to the Northward of us, and that we are upon the left hand side of its path. At what distance we are from the centre can only be judged of by the quickness with which the wind veers round ; and it will be clear that if a ship stood exactly still with the hurricane coming direct towards her, she might have the wind always in one direction till the centre passed her, when she would probably have a shift exactly in the opposite direction.t The seaman will now understand how it is that he may be running into a Hurricane or scudding in company with one—which no one of course desires to do—and how important it is that a knowledge of their usual paths should be obtained; for they seem to have in all countries tracks which we may call their usual paths. As an example how a vessel may run into a hurricane, let us suppose upon our Chart, the Amherst, bound across the Bay from Chittagong to Coringa. It is clear that her course then lies across the track of the Hurricane, and that, if ignorant of what we now know, she might with a little alteration of time, and tempted by the fine Easterly Gale, run into the middle of it; for till now, though a falling Barometer would teach the seaman that he was to expect a tempest, he was quite ignorant, or had only some general rules derived from very partial experience, to inform him where it was beginning, how it would blow, and how he could escape it. We shall know this as I have said before, when we know the usual path of our Indian Hurricanes.
* In an able review of Col. Reid’s work in No. 23 of the Madras Journal of Literature and Science by T. G. Taylor, Esq. H. C. Astronomer at Madras, he says, “The East India Gales appear invariably to travel from the coast of Arracan towards the West, the curves conforming gradually to the slope of the shore until in about the latitude of Madras when their course is due South, after which the curve binds again towards the West, the violence of the storm seldom extending below Cuddon or Porto Novo.” Mr. Taylor speaks here of a gale. He does not observe that he has described the curve which a hurricane (i.e. a turning gale) would make on three sides of its circle.
f Col. Reid, p. 8.
The question of scudding or heaving to must it is evident depend upon the commander's judgment as to the position in which he is, his sea-room and the like; but the tack on which he ought to heave to is so clearly indicated by Col. Reid's directions that I cannot do better than extract them; he says page 425,
“ Rules for laying Ships to in Hurricanes.—That tack on which a ship should be laid to in a hurricane has hitherto been a problem to be solved; and is one which seamen have long considered important to have explained. “In these tempests when a vessel is lying to and the wind veers by the ship's head, she is in danger of getting stern-way” even when no sail is set; for in a hurricane, the wind's force upon the ship's masts and yards alone will produce this effect, should the wind veer ahead, and it is supposed that vessels have often foundered from this cause. “When the wind veers aft as it is called, or by the sterm, this danger is avoided, and a ship then comes up to the wind instead of having to break off from it. “If great storms obey fixed laws, and the explanation given of them in this work be the true one, then the rule for laying a ship to follows like the corollary to a problem already solved. In order to define the two sides of a storm, that side will be called the right hand semicircle which is on the right of the ship's course, as we look in the direction in which it is moving, just as we speak of the right bank of a river. The rule for laying a ship to will be, when in the right-hand semicircle to heave to on the
starboard tack, and when in the left-hand semicircle on the larboard tack in both hemispheres.”
As an example of this on our own diagram. If a line be drawn across those of the 4th and 5th N. 76° E. and S. 76° W. or about WBS. S. and EbN. J. N., which is the track we have supposed for the hurricane; it will be seen that all the vessels above it, or to the right hand of the hurricane's path, had the wind veering from NE. to South, and were thus safe upon the starboard tack, and all those below it,” or on the left hand side, had the wind veering from N. to SW. and were thus safe on the larboard tack. The vicinity of the shore, or the necessity of wearing to ease the masts, if the rigging has stretched too much upon one tack, may oblige the seaman to vary from this rule; and close to the centres of the hurricanes anomalies may be found; but it will be seen at once, I think, without further explanation, of what great value it must ultimately prove to him. I annex here a public order recently issued by the Government of India, and a memorandum by the Lords of the Admiralty and by Lord Glenelg, which will assist in shewing both the seaman and landsman what we require in the way of information on this subject. Calcutta: Wednesday, 11th September, 1839.—NoTIFICATIon.—The importance of investigating the course and Phaenomena of Storms has been brought to the notice of Government by the Hon’ble Court of Directors; and the Hon’ble the President in Council is in consequence desirous of obtaining local Registers of these Phaenomena taken simultaneously at as many stations of India as may be found possible. The public Officers of the different settlements and stations of India are accordingly invited and requested, upon the occurrence of any Hurricane, Gale or other Storm of more violence than usual, to note accurately the time of its commencement, the direction from which the wind first blows, whether in gusts or regular, and whether accompanied with rain, thunder and lightning or other Phaenomena. Also to note, with as much accuracy as possible, the changes of direction in the wind, and the time of the occurrence of each, and lastly, the duration of the Gale and in what quarter the wind is when it ceases. The variations of the Thermometer and Barometer at each period noticed will also be of importance if the means are forthcoming of making such observations. The President in Council refrains from making it the business of any particular Officer to note the above circumstances, but relies on the known desire of all enlightened persons to promote objects of scientific and useful enquiry that the public Officers will arrange in such manner as to ensure that the observations will be taken by some one in the vicinity of each station. Reports upon matters of the description comprehended in this Order may be forwarded to the Secretary to Government in the General Department, free of postage, (superscribed “Storm Report.”) A scientific gentleman in Calcutta has obligingly undertaken to combine all reports that may be so received into a synopsis for exhibition of the results in the manner adopted and recommended by Colonel Reid, R. E. By Order of the Hon’ble the President of the Council of India
* From being taken aback. This taking aback in a tempest we all know to be most dangerous, not only on account of the getting sterm-way here mentioned; being pooped, dismasted, and the like ; but from another danger which is not sufficiently adverted to I think; and this is, that a vessel, may in one of the terrific gusts which accompany these sudden shifts of wind be thrown on her broadside in the trough of the sea with her deck towards the sea! In such a case she is in the position of a vessel on a reef which has fallen over to seaward; and there is every chance that her hatches would be beaten in; which would swamp her. A parallel case to this is mentioned in Col. Reid's work, page 221, of the H. C. S. Diana, when part of the upper forehatchway was stove in by the weight of the water above it, and the vessel nearly swamped in consequence. Hatches, particularly those of the upper deck, should not only be made stouter then they usually are (they might for lightness be lined with sheet copper or iron) but moreover two extra strong fore and aft-pieces should be made to ship parallel with the middle piece, halfway between it and the side, so as to afford additional support in cases like this. I shall be told that we know of very few instances of this accident. This may arise from few escaping to tell the tale. The number of well-found, stout ships, ably manned and commanded, which disappear induce us to believe that, apart from fire, there are storm-dangers which we can only guess at. I think this may reasonably be supposed to be one of them. H. P.
in Council. H. T. PRINSEP, Secy. to the Govt. of India. * The places of the Justina and Eden, by an oversight, are unfortunately omitted
in the diagram of the 5th. It will be seen that they had the wind at SW. and SW by. on that day.
- Admiralty, Dec. 28th, 1838. The Lords Commissioners of the Admiralty having had under consideration the general utility of recording with clearness and precision, in the log books of all Her Majesty's ships and vessels of war, the actual state of the winds and weather, have thought fit to order that henceforward in each page of the log book two columns should be introduced, wherein the force of the wind and the appearance of the atmosphere, shall be every hour registered according to the annexed scheme, a copy of which shall be pasted into each book, and painted on the back of every log board or log slate: and two more columns shall likewise be given for the purpose of entering the heights of the barometer or simpiesometer, and thermometer, when such instru
ments may be on board.
By command of their Lordships,
To all Captains, and commanding officers of Her Majesty's ships and vessels.
FIGUREs To DENOTE THE Force of THE WIND. 0 denotes Calm.
1 Light Air, . . . . . . just sufficient to give Steerage way.
2 Light Breeze, .. 1 to 2 knots.
3 Gentle Breeze, ..
sail, and clean full, would $o in smooth water, from
4 Moderate Breeze,
6 Strong Breeze, | Single-reefs and top
in which th hi ld -7 Moderate Gale, H. .."? Double reefs, jib, &c.
8 Fresh Gale,.... Triple reefs, courses, &c. 9 Strong Gale, ... J UClose reefs & courses.
Close reefed main top
10 Whole Gale, .. i. which * * *y sail and reefed fore' ' ' ' ' ' " sail.
11 Storm, . . . . with which she would be o:
duced to A - ... Stay-sails.
12 Hurricane, ... to which she could shew ... No canvas.
LETTERs To DENotE THE state oF THE WEATHER.
b Blue sky—whether with clear
| p Passing showers.
cloud. By the combination of these letters, all the ordinary phaenomena of the weather may be recorded with certainty and brevity.
b c m Blue sky, with detached opening clouds, but hazy round the horizon. g v Gloomy dark weather, but distant objects remarkably visible. q p d 1 t Very hard squalls, and showers of drizzle, accompanied by lightning, with very heavy thunder. Nautical Magazine,—March, 1839.
Memorandum respecting the Records to be kept of the state of the Weather in the British Colonies.
The Captains of Ports, Harbour-Masters, and Keepers of lighthouses, or, where those officers do not exist, some other competent public functionary, should be required to keep journals of the weather, on the principle of the log books of ships. A column should be specially reserved for inserting the height of the barometer. Under the head of “Remarks,’ should be entered all meteorological observations considered worthy of particular notice. When the keeper of a journal may hear that a vessel has encountered a storm, he will enter in it any information on the subject which he can rely on, together with the name of the ship, of her owner, and of the port to which she may belong. With the view of tracing the course of storms, the Trinity Board of London have given directions for the adoption of measures to obtain a more accurate record of the weather, than has hitherto been kept, at the lighthouses of Great Britain and Ireland. The keepers of these lights having the opportunity of taking their observations by night as well as by day, great advantage may be derived from employing them in this manner. Officers in charge of Colonial lighthouses should be instructed to keep similar journals. In noting the wind's force, both in the Harbour-Master's journals and in the lighthouse reports, it is desirable that the officers should adopt the numbers for