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1. Endymion. 3. Amazon. 5. Montagu.
7. Albemarle. 2. Alcmene. 4. Egmont. 6. Vengeance. counts and situations. Several of the arrows point in direct opposition to the convergent theory; especially those at St. Vincent, and near Barbadoes. The latitudes of these places are nearly the same; the wind at one is northwest, and at the other southeast ; according to Mr. Espy, there
, fore, the middle of the storm would be north and south of the same parallel, at the same time. At the various stations, the wind went round the compass in conformity with the law of rotation. We may refer particularly to the report of the intendant of Martinique, to the Endymion, and indeed to all the vessels. To follow the storm in its whole progress, and point this out in detail, would occupy too much space.
This hurricane of the 11th of October is altogether the most affecting of those mentioned in Colonel Reid's work. It is also the most complete in its annals. It is curious to read the musty old log-books, which were laid upon the shelf sixty years ago, without the least probability that they would ever see the light again. Written with technical conciseness, they appear to exhibit a singular insensibility to the perils and hardships they briefly record. Here and there the cry of the strong swimmer in his agony echoes in our ears ; but the notice both of the living and the dying is the mere mention of a fact, and the lament over many
" a brave vessel, Who no doubt had noble creatures in her,
Dashed all to pieces," is confined to the hasty condolement of an official despatch.
Another storm mentioned in Colonel Reid's book, and selected by Mr. Espy as an illustration of his theory in opposition to the rotary law, is that of the middle of August, 1837. He has undertaken to give the position of the storm at noon of the 18th, the period of most rapid change. We have no hesitation in saying, that it is impossible to ascertain the directions of the wind at this hour, for all the vessels on his chart, with any approximation to certainty. For instance, “ The Delaware, on the 17th, lat. 31° 30', long. 76° 20', had a severe gale E. S. E. and then W., which continued till the 20th ” ; * and it is from loose statements like this, that, without any qualification, he determines the position and wind of many of the vessels at noon of the 18th, as if they had been expressed at that precise moment. The following is Mr. Espy's projection. |
“ Position of storm at noon on the 18th of August, 1837.
1. Wind at Wilmington, P. M. of 18th. 8. Westchester, on 18th. 2. Oglethorpe on loth.
9. Duke of Manchester, till P. M. 3. West Indian all 181h, from 2, A. M. of 181h. 4. Rawlins, all 18th, from 2, A. M. 10. Delaware, on 17th, and probably 5, Ida, all day of 18th.
on 18th, changing round to west6. Penelope, on P. M. of 18th.
ward on 20th. 7. Yolof, till 8, P. M. of 18th. 11. Cicero, on 18th.”
We have to remark concerning it, that the wind at Wil
Espy, p. 237. VOL. LVIII. No. 123.
Ibid. p. 238. 42
mington is right ; that the position given to the Oglethorpe
The wind of the Rawlins is north, instead of S. W. as Mr. Espy puts it. There is no authority for the wind of the Ida ; it is described in her log-book as "veering from N. E. to S. W.” | The Penelope is right. The log-book of the Yolof shows no wind until after 8, P. M. of the 18th.Ş According to the brief newspaper paragraph, which is the only authority, || the Westchester was in the same latitude in a gale of wind for two days. This is absurd, and as there are no means of determining her correct place, she is rejected. Mr. Espy has put down the Duke of Manchester in a wrong position. She differs from the Rawlins more than two degrees in her latitude ; 1 but on the chart they are brought near together, and their winds (that of the latter being misstated) are drawn so as to converge. We have already quoted the report of the Delaware ; it evidently cannot serve any purpose that aims at accuracy. The Cicero is also rejected; her winds agree well enough with the rotary law, but are not sufficiently specific.** Lastly, the ships Sophia and Westbrook, the bark King Philip, and the brig Mary, within the influence of the storm, are omitted on
Mr. Espy's chart.tt
We subjoin a correct view of the storm on the 18th, to which the same remarks will apply as to our first amended projection.
In addition to the facts given above, Mr. Espy has cited the accounts of many hurricanes and gales collected by himself, as proofs of his theory. It is, of course, out of the Espy, p. 238.
| Reid, p. 88. # Ibid. p. 102. ş Ibid.
|| Reid, p. 86. T Ibid. p. 116. Espy, p. 237. it Reid, chap. 5.
pp. 106, 107.
9. West Indian.
10. Rawlins. 3. Westbrook.
8. Duke of Manchester. 11. King Philip. question to enter upon a critical examination of them here. We will observe, however, that Mr. Espy's summation of the “labors of the joint committee,” and his conclusions therefrom are wholly unsatisfactory. In the storm, too, of the 16th, 17th, and i8th of March, 1838, of which Mr. Espy gives a chart showing the probable limits of its extent, we are required to admit, that the wind blew inwards from the borders of the storm universally ; when, in fact, of sixteen or eighteen arrows touched by the limiting circle, or included within it, one half, namely, those numbered 1, 12, 14, 17, 18, 21, 27, 28, 30, do not point inwards. Mr. Espy, before the British Association, quoted the storm of January, 1839, in Great Britain, as sustaining in all its phenomena the theoretical principles he was advocating. This storm has since been again examined by Mr. Hopkins of Manchester, with information furnished by Mr. Smith of Liverpool, in a pamphlet comprising one hundred and fortyone accounts, taken from the local newspapers in various parts of Ireland, Scotland, and England. He did not find Mr. Espy's “converging streams rushing towards a centre."
The accounts of storms taken from the public prints are generally vague, 'meagre, and unsatisfactory. Their object is
not to convey accurate meteorological knowledge, but to relate local and commercial news. There are two modes of treating these accounts ; either to present them entire, as Colonel Reid and Mr. Redfield have done, or, like Mr. Espy, to make selections. When the latter course is pursued, there is danger of considering those facts as the most reasonable and credible, which accord with the preconceived opinions of the theorist, whilst those at variance with them are likely to be rejected as imperfect and irreconcilable with an assumed law of nature. Éven such as are accepted may be perverted by prejudice, or a want of proper prudence in guarding against its influence. The numerous errors of Mr. Espy that we have just exposed, render these remarks peculiarly applicable to him. They seriously impair our confidence in his accuracy as an observer, or recorder of facts ; in which light we have hitherto considered him.
We may dispense with any labored argument to show, that if there be a fixed law of nature, according to which those storms act, that constitute the seaman's worst dangers, the knowledge of it will prove of infinite importance in preserving the lives and property exposed to hazard in com
It is for this reason, that we have extended our criticism further than may be altogether interesting to the general reader. The result is, that we find the law of Mr. Redfield fully sustained ; and we see, that the Roval Society * and the British Association † concur in his views. Mr. Redfield, however, has modified his first conception so far as to admit an inward and upward tendency, and a consequent spiral action, in the winds that compose the body of the storm. This expresses our own view more completely. A rotary motion, if continued a sufficient length of time, must, we conceive, finally terminate in a spiral revolution.
The centrifugal action tends constantly to heap up the air, and increase its density, upon the outer borders of the storm, and the increased density occasions an inward pressure. We may suppose these two forces to be, for a time, equally balanced. But the rotary movement experiencing retardation
Instructions to the Officers of the Antarctic Expedition, Phil. Mag. Vol. XV, 3d series.
† Professor Forbes's Supplementary Report.
| Paper read by Mr. Redfield before the Philosophical Society at Philadelphia, January 15th, 1841.