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tained that the winds at Dover have blown as follows:

N. W. W. S. W. S. S.E. E. N.E. N. 91 35 195 8 37 18 118 27 From these elements the three western winds are at Dover 321 out of 529, or 606 to a thousand. "At Lancaster, by Dr Campbell's observations, upon an average of seven years, the winds were: N. W. W. S.W. S. S.E. E. N.E. N. 26 92 47 51 35 17 67 30

Giving to the western winds 452 in a thousand.

"At Sidmouth in Devonshire, the result of 406 observations on the winds was as follows: N.W. W. S. W. S. S.E. E. N.E. 95 42 58

66

38

13

N. 40 54

Here we find the western winds prevailing 199 days in the year, or 546 in a thousand.

"According to a meteorological register kept by Major Rooke for sixteen years, from 1785 to 1800, inclusive, the most frequent winds in England blow from the S. W. and N. W.; and during the last eight years of this period, the south-west winds were observed to be more prevalent, and those from other quarters to be less so; while the average number of days in which the north-east wind prevailed, appears to have been much the same during both periods. This statement, as far as regards the prevalence of the north-west winds, is certainly at variance with the observations of all other meteorologists; since the wind from this quarter more seldom occurs in all parts of England, than from any other quarter, with the exception of the south and the east in some parts of the island.

Winds of Scotland. †—"The following comparative view of the winds on the east and west coast, has been given by Sir John Sinclair.

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TABLE XXIV.

Winds at Kinfauns Castle, Seat of Lord Gray, Scotland, from 1813 to 1825 inclusive.

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Summary of the Winds of North America and of the north-western part of Europe.

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* See Table No, XXI.

†The numbers in this column seem to be the same as those in that headed by the name of Sir John Sinclair.

The results of this summary table, and those from which it is constructed, would render excusable a suspicion that the elements were selected to support a theory, but so far from such a process having been followed, the elements were arranged as they presented themselves, and many of the most important are scattered over the volumes of this Encyclopædia, in reach of the reader; the correctness of our application may therefore be tested. Errors of calculation there may be, but they are involuntary, and we trust not of such extent as to seriously influence the aggregates.

If, as we assume, these tables of the winds are taken as solid data, the true cause of the great difference of temperature between given latitudes on North America, and North-western Europe is determined. We find from table 27, that the three western winds over the former section of the earth are, to all other aerial currents, as 556 to 1000, on a mean from the Pacific to the Atlantic ocean; and that, also on a mean, the three western winds prevail over North-western Europe, as 571 to 1000. If the northern winds were included with the western, as in reality they might have been correctly, on both continents, the result would remain nearly the same as already deduced.

To the American Almanac for 1832, page 98, the following is appended as a note.

"The number of days required by the packets between Liverpool and New York, to make the passage outwards and homewards, places this (the author's observations on the trade wind in the text) in a striking point of view:

"The average of the whole of the passages made by the packets, in six years, from Liverpool to New York, that is from east to west, is 40 days. "The average, during the same period, of the same vessels, from New York to Liverpool, or from west to east, is 23 days."

These voyages give a prevalence to west over all other winds of 606 in a 1000, agreeing in an astonishing manner with the results in table 27.

According to Professor Playfair, and other authorities, the winds blow almost incessantly from the south-eastern coast of Asia towards the Pacific

ocean.

Can there be any farther hesitation in ascribing the intense winters of North America, to that prevailing and powerful current of air borne from an immense snow covered and frozen continent? Or can there exist a doubt, but that the comparatively uniform temperature of North-western Europe is produced by the immense preponderance of western winds from a wide and perennially open ocean? Again, is it not now demonstrated, that the winds of both continents do not depend for their general course, on either land or water?

It may be also remarked, that the prevalence of western and north-western winds is really but very slightly influenced in their respective occurrence by the seasons of the year. It is not, however, to the actual prevalence of the western currents of air that their overwhelming agency is entirely to be attributed; their relative intensity must be taken into comparison. According to Mr Hutchinson's

Before

observations at Liverpool, (see vol. viii. page 525, 2d column) the west wind blew with most rapidity and force, and next to it in violence, were those of the south-west and north-west. These conclusions accord perfectly with the same winds of North America above N. Lat. 35°, and there can be no risk in stating, that if we suppose the whole power of the wind to be represented by 1000, and if we add their force to their occurrence, the western winds comprise at least the seven-eighths of the whole aerial stream over the space embraced in our estimates. The bending of the trees on both continents, already alluded to, is a phenomenon obvious to the most careless observer. drawing our final conclusion, we proceed to give some of the best authenticated results obtained by observations made with the Thermometer. An opinion has long prevailed, and to considerable extent still prevails, that the valley of Ohio in particular, and the basin of the Mississippi generally, has an aerial temperature considerably higher than is experienced on corresponding latitudes along the Atlantic slope of the United States. Such an error, for such it is, is far from being one of those innocent conclusions in opposition to obvious facts; it has greatly contributed to emigration; and we shall soon see, that so contrary is reality, that what might be expected is true; the mean and extreme temperature increase with height and exposure, over the Mississippi basin, as they do every where else on earth. The authorities on which the mean temperature is deduced are named in the tables, but we preface those respecting the United States. by extracts from the preliminary remarks to Lovell's Meteorological Register, dated Washington, September 1826.

"The posts at which these observations were made are situated between 27° 57' and 46° 39′ of north latitude, and between 67° 04′ and 95° 43′ of longitude west from Greenwich; embracing an extent of 18° 42' of latitude, and 28° 39′ of longitude. The elevation of the north-western, or interior, stations above those on the Atlantic coast has not been accurately ascertained; the following however is believed to be near the truth. Fort Brady, situated at the outlet of Lake Superior, is 595 feet above the level of tide water; Fort Howard, at the southern extremity of Green Bay, which empties into Lake Michigan, 600 feet; Fort Crawford, at Praire du Chien, near the junction of the Wisconsan and Mississippi rivers, 580 feet; Fort Snelling, near the junction of the St. Peter and Mississippi rivers, 780 feet; Council Bluffs, a few miles above the junction of the Platte and Missouri rivers, 800 feet. Baton Rouge, on the Mississippi, 120 miles above New Orleans, and Cantonment Jesup, near the Sabine river, 25 miles from Natchitoches, are in Louisiana; Cantonment Clinch near Pensacola, Cantonment Brooke near Fampa Bay, and St. Augustine, in Florida. Fort Moultrie is in the harbour of Charleston, South Carolina; Fort Johnston near Smithville, North Carolina; Fort Severn at Annapolis, in Maryland; Fort Mifflin in the Delaware, 6 miles below Philadelphia; Fort Columbus in the harbour of New York; Fort Wolcott in the harbour

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Comparative view of mean temperature along the Atlantic slope, and interior basin of the United States, as also of the North American Polar Sea, corrected by the observations of Haines, Little, Brantz and others, on the former, and Lewis and Clark, Captain Parry, Drs. Drake and Troost, &c. of the interior

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Comparative view of mean temperature on Northern Africa, and in Europe as far eastward as St. Petersburg; compiled from Malte Brun's Geography, Edinburgh Encyclopædia, &c.

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