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intervals, skip straining and labouring very heavy, took in the foresail occasionally—Daylight ditto weather, with a high confused sea. Noon more moderate gale, decreasing weather, winds WSW. strong breezes, cloudy, with a heavy sea. Midnight, strong breezes and cloudy, lat. at noon 11°. 56' N.

Report from Captain Campbell, Assistant Surveyor General, Madras.

I have the honor to report that the Barometers at Royacottah and Bangalore were affected by the Storm which took place at Madras at 2 A. M. of Sunday the 16th May 1841, and that at Royacottah the force of the gale was felt for some hours.

The observations at Royacottah were made by myself, with an open cistern instrument, on the plan described in the 29th No. of the Madras Journal, with a tube 3-10 inch in diameter, filled and boiled by myself.

The observations at Bangalore were made by the Rev. John Garrett, of the Wesleyan Mission, with one of Newman's iron cistern Barometers, with a tube filled and boiled by myself for the Medical Board at Madras, which on frequent comparison never differed the 1-100th part of an inch from my own.

The observations are reduced, except for temperature, as the variation from 80° of Fahrenheit by either instrument was but three or four degrees.

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Depression greatest at Royacottah by *0'4 inch.

The very slight variations in the difference of the observations between the two instruments at a distance of forty miles, shews that the observations deserve the utmost confidence. The greatest depression observed was at Royacottah on the 17th, equal to 0 212 inch below the pressure on the 12th.

17

Observations on the weather at Royacottah on the 16fA, at 10 A. M.

Wind N.W. overcast, with Nimbi. Thick in N.E.; lower stratum of clouds moving rapidly with a N.E. current; rain in N.E. and S. at a great distance (forty miles), air very clear. Four P.m. overcast; wind at N. drizzling and heavy rain. At night, about two in the morning, wind increasing to a gale, direction not certain, believed, S.E.; 17th, at sun rise wind quite fallen.

At Bangalore,

16fA May.—10 A. M. wind moderate, very cloudy and oppressive. At day-light 5 A. X. Barometer 26-868, rain at night 17th; 10 A. M. very high wind, stormy; it is to be noted, however, that in this month high winds prevail at Bangalore.

It will be remarked that the gale was felt simultaneously at Royacottah and at Madras.

Royacottah, 6th August, 1841.

The Helen Mary, in company with the John William Dare, had nearly the same weather, but her log affords no Lat. nor Long, from which to deduce her position.

The Barque Champion also from Moulmein to Madras, in Lat. 10° 1' N. to Lat. 9° 23' had tremendous gusts of wind from WNW. on the 16th, reeling to the SW. which seem to have been the usual monsoon; but as there is no longitude with her log it is quite useless as an authority.

The Barque Ayrshire from Malacca to Madras has obliged usjwith a capital log, but she was fortunately for her, though unfortunately for us, in lat. 6° 3C N. and long. 89° 54' on the 15th. She had here a heavy SW. monsoon, varying from SbW. to SW.

The Bengal Merchant from Moulmein to Madras passed through Duncan's passage in the Andamans on the 15th with strong SEbS. breezes and clear weather, which would agree with the centre of that day if we suppose the storm to have extended so far, which 1 do not think it did.

The Barque Catharine, about midnight on 15 th had a shift of wind in a gale from NE. to SW. and from that, to noon 16th, strong gales from SW. being then in 8° 27' N. and 82° 32' E. Her vicinity to the high land of Ceylon, and her being considerably to the Southward, with the SW. monsoon blowing strongly, makes her's also a very uncertain datum,

and certainly not to be compared to the exactness derived from that for the Madras ships and shift of wind on this day. 1 have however marked her position for the 16th and 17th on the chart.

The Barque Amelia from Vizagapatam to Madras had heavy gales varying from ENE. to NE. on the 16th in lat. 14° 51' N.; no longitude, given; but she was not very far from the coast, and thus shows clearly enough that the storm extended to about the distance we have taken As usual she had SE. winds on the following day.

We have two very good stations for this storm, from which we are enabled, I think, to fix its track and rate of travelling with tolerable accuracy. The first of them is on the loth, when we have the French ship Petite Suzanne's log and that of the Hydroose, which give a centre at noon on that day about where 1 have placed it, or in lat. 9° 52' N. long. 87° 12' E. We have then Captain Biden's careful account giving the shift of wind at Madras at 8. P. M. on the 16th. Now from noon on the 15th to 8 p. M. on the 16th is 32 hours, and the distance is about 453 miles in that time, or 340 miles in the 24h. or 14^'th per hour. Taking eight hours of this rate, or 113 miles, backwards from Madras on the ESE. and WNW. line of its track, (it will be seen by Captain Biden's letter that at Madras this was its track the shift being from NNE. to SSW,) we have for noon of the 16th the spot I have marked. 113 miles ESE. of Madras ; and as we find by the various logs of the vessels which slipped from Madras roads, that the shifts or veerings of the wind were between noon and 5 P. M., as they had necessarily run out towards it to get the best offing they could, we cannot be far wrong. This centre of the 16th agrees very remarkably with the log of the Hydroose, which vessel had her shift of wind on its track, and if our rate is correct, about 10 hours before noon, or at 2 A. X. of the 16th. It will also, with allowance for the drift (for her track was not the strait line it is laid on the chart) agree very well with the position of the Petite Suzanne, which vessel, by the rapid veering of the wind, must have had the centre not far from her at one time; and I attribute to this the anomaly of her having had the wind for about three hours from NE. to East. It will be bome in mind, in considering the two positions of this vessel, that there is good reason to suppose that in these storms strong partial marine currents may be at times created.* We may also remark of hert, hat * Col. Beid, and various logs in ray preceding Memoirs.

the is about as far from the centre at noon on the 16th as she was at noon of the 15th, and that the weather seems to have moderated on the former day to about the degree of violence at which it was on the latter, which is also an indirect testimony to the truth of our estimate of the places of the centres. These are tolerable good data for the centre of the 16th, and as the storm was then rapidly approaching the shore, it would as usual, in all probability, begin to show those anomalies which there seems no reason to doubt do occur when this is the case. It is most unfortunate that we have not, in the logs of the J. W. Dare and other vessels, any computed positions, even by dead reckoning, and not even a longitude! Nothing can more truly show the difficulty we meet with in procuring our information, than the fact, that in this instance, even the Master Attendant of the port could get only returns deficient in one of the most essential points!

I was at first inclined to supposed that the shift of wind experienced by the Catharine might have been that of another storm, which reaching Vizagapatam on the 18th was the cause of the loss of the Isadora, but the entire want of latitudes and longitudes, and even of the direction of the wind in the storm of the 18th at Vizagapatam, prevent our tracing this theory. Vizagapatam is however such a very unsafe anchorage for a vessel of any size in most weathers, that the Isadora may as probably have been wrecked by a strong Southerly gale as by a N. Easterly or Northerly one. I am inclined to suppose that it was merely a monsoon gale—i. e. the monsoon setting in with the force of a gale ; which very frequently occurs.

I have before alluded to the rate of motion of this storm, which was apparently as high as 14-j per hour. I have made the vortex 310 miles in diameter, because I think that the logs of the Hydroose and Petite Suzanne fairly shew them to be about on the outer verge of the storm at noon on the 15th, and from those of the Amelia and Catherine to the North and South, with the changes experienced by the Hydroose and Petite Suzanne to the East, and at Madras to the West, we cannot take it at less on the 16th.

Our only reports of its progress inland, where it would first meet with the lower ranges of the Eastern Ghauts forming the Pulicat Hills, about 60 miles inland from the coast, and successively with those which flank the table lands of Mysore, are those from the Assistant Surveyor General at Royacottah, and from the Rev. Mr. Garrett at Bangalore, included in his letter. The distance from Madras to Royacottah is about 160 miles W. by S. i S. and from Madras to Bangalore about 215 miles W. J S.

We see that the centre passed Madras about 8 P.m. on the 16th, and taking it then to have a semi-diameter of about 150 miles, and to have travelled in the same direction as before, it would have passed very considerably to the Northward of these two stations, and should have begun to be felt at Royacottah at 8 p. M. on the 16th ; where, as we indeed see, the appearances and wind were suspicious, though unfortunately we have no direction of it marked between 4 P. M. and 2 A. M. where it is only "believed" SE.; which would make the centre pass to the Northward. At Bangalore we have unfortunately no direction of the wind at all!

The Baiometrical table however, as compared with that of Madras, is of value, though it would have been far more so had any intermediate heights been observed from between 10 and 4, while the weather was so threatening. Taking the extreme Madras depression to have been at 7. P.m. of the 16th 290690, and that of Royacottah and Bangalore at 4 P.m. on the 17th, and that those epochs indicate the passage of the centre, we have then 21 hours for the time it took to travel from Madras to Royacottah, or 160 miles, which gives about 8 miles per hour as its rate of travelling when it reached the land, and had to force its way over ridges of hills; while at sea it was, as we have seen, travelling at the rate of 14-j miles per hour, a very remarkable instance of the effects which ridges of mountains (for Bangalore is at least 3000 feet above the sea, and the crests of some of the Eastern Ghauts thereabout cannot be much less than 5000 feet) produce on the rate of motion of storms from seaward.

It is worth while to compare this retardation from 14 miles to 8 miles per hour, or say one half, with what the Cuttack storm of 1840 (Third Memoir*) appears to have also experienced from the same cause, but where the ranges of hills were perhaps not so high. This storm seems to have been checked from about 350 miles per day, its greatest rapidity, to 113 and 175 miles, or about one half its velocity on its approach to the land.

We do not know any thing of the Cuttack storm inland. The Madras storm, which we are now considering, seems to have been nearly

• Journal Asiatic Society, vol. ix. p. 1009.

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