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nings and thunder. I hear no further of it westward than out of Denbighshire, where it left St. A saph to the right, and did much damage between it and the sea, breaking all the windows on the weather side, killing poultry, lambs, and a stout dog; and in the north part of Flintshire several people had their heads broken, and were grievously bruised in their bodies. From Flintshire it crossed over the arm of the sea that comes up to Chester, and was only felt in Cheshire, at the very N. W. corner of the Peninsula, called Wirall, between the Æstuaria of Chester and Liverpool, at a town called W. Kirkby, where it hailed only for three minutes, it being on the extreme point of it on the right hand, but it thur dered dreadfully, and was here about three in the afternoon ; but the main body of it fell upon Lancashire, in a right line from Ormskirk to Blackburn, on the borders of Yorkshire ; the breadth of the cloud was about two miles, within which compass it did incredible damage, killing all sorts of fowl and small creatures, and scarcely leaving any whole panes in any of the windows where it passed; but, which is worse, it ploughed up the earth, and cut off the blade of the green corn, so as utterly to destroy it, the hailstones burying themselves in the ground; and the bowling-greens, where the earth was any thing soft, were quite defaced, so as to be rendered unserviceable for a time, The hail-stones, some of which weighed five ounces, were of different forms, some round, some half round, some smooth, others embossed and crenulated, like the foot of a drinking-glass, the ice very transparent and hard, but a snowy kernel was in the middle of most of them, if not all; the force of their fall showed they fell from a great height. What I take to be most extraordinary in this phænomenon is, that such a sort of vapour should contioue undispersed for so long a tract, as above sixty miles together, and in all the way of its passage occasion so extraordinary a coagulation and congelation of the watery clouds, as to increase the hail.stones lo so vast a bulk in so short a space as that of their fall.

Io a subjoined account of the same storm we are told as follows, though the correspondent does not mention the place he writes from:

“ We had only the extreme skirt of the shower here, and there fell not above one hundred hail-stones in our court, but they were much larger and harder than we had ever seen. Some measured about five inches round. Scarcely any of them was so little as a musket bullet, but most of them far larger, and of that figure. Some indeed as large as hens' eggs, and of half a pound weight. Many sea-fowl and land-fowl were killed.”

Phil. Trans. 1697.

4. In Hertfordshire.

By Mr. Robert Taylor. Ar Hitchin, on Tuesday May 4, 1767, about nine in the morn. ing, it began to lighten and thunder extremely, with some great showers between. It continued till about two in the afternoon, when on a sudden a black cloud arose in the S.W. the wind being E. and blowing hard; then fell a sharp shower, with some hail-stones, which measured seven or eight inches about. But the extremity of the storm fell about Omley, where a young man was killed, and one of his eyes struck out of his head ; his body was all over black with the bruises; another person nearer to Offley escaped with his life, but much bruised. In the house of Sir John Spencer, 7000 quarries of glass were broken, and great damage done to all the neighbouring houses thereabouts. The hail fell in such vast quan. tities, and so great, that it tore up the ground, split great oaks and other trees, in great numbers; it cut down great fields of rye, as with a scythe, and has destroyed several hundred acres of wheat, barley, &c. insomuch that they plough it up, and sow it with oats : the tempest was such when it fell, that in four poles of Jand, from the hills near us, it carried away all the staple of the Jand, leaving nothing but the chalk. I was walking in my garden, which is very small, about thirty yards square, and before I could get out, it took me to my knees, and was through my house before I could get in, which was in the space

of
a

mi. nute, and went through all like a sea, carrying all wooden things like boats on the water, the greatest part of the town being under this misfortune. The size of the hail.stones is almost incredible; they have been measured from 1, to 13 and 14 inches about. Their figures various, some oval, others round, others pointed, some flat *.

[Id. 1697.

• There is a subjoined account of a similar storm in the same county, in June 1697, during which the stones that fell, upon being measured, proved above nine inches in compass.

[EDITOR.

CHAP. XL.

ON WINDS OR ATMOSPHERICAL CURRENTS.

SECTION I.

General Remarks on the Nature and Origin of Winds, Trade.

winds, Monsoons, partial Winds, and Hurricanes. N.

o phænomenon in meteorology has more engaged the attention of men of observation than the winds, or those currents which so often disturb the tranquillity of the atmosphere. The subject is not only curious, but highly interesting; for upon their direction and force navigation in a great measure depends; the temperature of climates is greatly influenced by them; and they are absolutely necessary to preserve the salubrity of the atmosphere. To be ac. quainted with the laws by which they are regulated, and to be able to calculate beforehand the consequences of these laws, has been in every age the eager wish of philosophers. But whether it has been owing to an improper method of studying this subject, or to its lying beyond the reach of the human faculties, philosophers have not made that progress in it which the sanguine imaginations of some individuals led them to expect. Many discoveries indeed have been made; and from the numbers and the genius of the phi. losophers at present engaged in this study, others equally important may be expected. But, notwithstanding this, many of the phæno. mena remain unexplained, and a rational and satisfactory theory seems still beyond our reach. I shall in this section give as complete a detail as possible of the natural history of the winds in the different parts of the world, and then consider how they may be ex. plained.

As the winds are much more regular between the tropics than in the temperate zones, it will be proper in the first place to begin with them.

In those parts of the Atlantic and Pacific Oceans which lie nearest the equator, there is a regular wind during the whole year called the trade-wind. On the north side of the equator it blows from the north-east, varying frequently a point or two towards the north or east; and on the south side of it, from the south-east, chang. ing sometimes in the same manner towards the south or east. The space included between the second and fifth degree of north lati. tude is the internal limit of these two winds. There the winds can neither be said to blow from the north nor the south ; calms are frequent, and violent storins. This space varies a little in latitude as the sun approaches either of the tropics.-In the Atlantic Ocean the trade.winds extend farther north on the American than on the African coast; and as we advance westward, they become gra. dually more easterly, and decrease in strength. Their force diminishes likewise as we approach their utmost boundaries. It has been remarked also, that as the sun approaches the tropic of Cancer, the south.east winds become gradually more southerly, and the north-east winds more easterly : exactly the contrary takes place when the sun is approaching the tropic of Capricorn t.

The trade-wind blows constantly in the Indian Ocean from the 10th degree of south latitude to near the 30th : but to the north. ward of this the winds change every six months, and blow directly opposite to their former course. These regular winds are called monsoons, from the Malay word moossin, which signifies a sea. son ft.” When they shift their direction, variable winds and vio. lent storms succeed, which last for a month and frequently longer; and during that time it is dangerous for vessels to continue at sea.

The monsoons in the Indian Ocean may be reduced to two; one on the north and another on the south side of the equator; which extend from Africa to the longitude of New Holland and the east coast of China, and which suffer partial changes in particular places from the situation and inflection of the neighbouring coun. tries.

1. Between the 3d and 10th degrees of south latitude the south. east trade.wind continues from April to October; but during the rest of the year the wind blows from the north-west ş. Between Sumatra and New Holland this monsoon blows from the south during our summer months, approaching gradually to the south. east as we advance towards the coast of New Holland; it changes

• Dr. Halley, Phil. Trans. Abr. vol. ii. p. 134. + Ibid.

Forest's Voyage, p. 95. Pr. Halley, Phil. Trans. Abr. vol.ii. p. 136: about the end of September, and continues in the opposite direction till April*. Between Africa and Madagascar its direction is in. fluenced by the coast; for it blows from the north-east from October to April, and during the rest of the year from the south. west t.

2. Over all the Indian Ocean, to the northward of the 3d de. gree of south latitude, the north-east trade.wind blows from October to April, and a south-west wind from April to October I. From Borneo, along the coast of Malacca and as far as China, this monsoon in summer blows nearly from the south, and in winter from the north by east §. Near the coast of Africa, between Mo. zambique and Cape Guardefan, the winds are irregular during the whole year, owing to the different monsoons which surround that particular place. Monsoons are likewise regular in the Red Sea; between April and October they blow from the north-west, and during the other months from the south-east, keeping constantly parallel to the coast of Arabia 1.

Monsoons are not altogether confined to the Indian Ocean; on the coast of Brazil, between Cape St. Augustine and the island of St. Catherine, the wind blows between September and April from the east or north-east, and between April and September from the south-west 1. The bay of Panama is the only place on the west side of a great continent where the wind shifts regularly at different seasons : there it is easterly between September and March; but between March and September it blows chiefly from the south and south-west.

Such in general is the direction of the winds in the torrid zone all over the Atlantic, Pacific and Indian Oceans; but they are subject to particular exceptions, which it is proper to enumerate. On the coast of Africa, from Cape Bayadur to Cape Verde, the winds are generally north-west ; from hence to the island of St. Thomas near the equator they blow almost perpendicular to the shore, bending gradually as we advance southwards, first to the

* Dr. Halley, Phil. Trans. Abr. vol. ii. p. 136.
+ Bruce's Travels, vol. i. p. 459.
| Dr. Halley, Phil. Trans. Abr. vol. ii. p. 156.

Dr. Halley, ibid.

Bruce's Travels, vol. i. ch. 4.
I Sir Walter Raleigh's Voyage. Forest's Voyage, p. 97.

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