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The ministry here have refused to license for- from him letters which indicated confidence in mally and entirely the new society or free-trade the accomplishment of new labors in philology, league but they allow it to organize itself and the branch of science in which Europe could transact business, provisionally. It would be re- hardly signalize a superior to a Pickering, within cognized, were not the elections so near at hand. her numberless circles of learning and authorIt has an able temporary bureau or committee, ship. consisting of eminent savans, peers, deputies; pro- The main paper of the latest bulletin of the fessors and authors in political economy. Paris Geographical Society is the report of the It is noted that Ibrahim Pacha receded from a distinguished committee of five, on the annual tour in Ireland, when he had got to Belfast, not-prize for the most important discovery in geograwithstanding O'Connell's fond interview with him phy. The committee restrict themselves to the of three quarters of an hour. The Liberator's enterprises and labors executed or terminated in antipathy to slaveholding disappeared in this in- 1843. They record several very useful expeditions and works. A liberal paragraph is bestowed on Lieutenant Fremont's performances, and Mr. Jonah Gregg's excursions are described. Nor is Mr. Thomas Falconer forgotten. Particular mention is made of Schomburgk's exploratory travels in British Guiana; M. de Wrede's and those of Captain Haines in Arabia; Don J. de Garay's examination of the Isthmus of Tehuantepec; and of the travels of Theophilus Lefebre and Dr. Beke in Abyssinia, between whom the annual prize of the academy is divided. In the beginning of the seventeenth century the Portuguese had great influence and considerable factories in Abyssinia. There existed then a great number of Christian churches, dating from the fourth century. Their creed was, in substance, the Roman Catholic, with some difference of rites akin to those of the Greek church. The same religion subsists in a certain number of towns and other inhabited places; it is held sacred so far as to render them inviolable.

Conformably to arrangements between the late pope and Czar Nicholas, the status of the Catholics in Russia is to be satisfactorily determined and secured. The Czar has appointed a committee, at St. Petersburg, to investigate their grievances, rights, and general situation; and one of the members is a Catholic. Nesselrode is the chairman; which is thought of the best augury. O'Connell may lose one of his favorite topics of invective against Nicholas.

Don Henry, the candidate the most popular in Spain for Queen Isabel's hand, has just dined at the Tuileries, after formal presentation by Martinez de la Rosa, the Gallico-Spanish representative. Don Henry is regarded as passing under the scrutiny of Louis Philippe-the Neapolitan match having become forlorn. We have another lion in the Duke of Soto-Mayor, ambassador for England, on furlough, son of the late Marquis of Casa Yrujo, and grandson of the late Governor McKean, of Pennsylvania. When his respectable uncle, of that state, a few months ago, called on him in London, he threw his arms about the relative's neck, and reminded him endearingly of the sports of his childhood in Philadelphia.

Mr. Rochet is thanked for having brought from the kingdom of Choa a considerable quantity of the plant Brayera anthelmintica, which most efficaciously expels the tape-worm. At Montpellier, Toulon, and even in Paris, the tea-plant has prospered, to the delight of the Royal Society of Agriculture. The traveller Hellert's accounts of the

The public schools maintained by the state, the departments, and the townships in France are more than forty-two thousand. There are seven-geography of the Isthmus of Darien are commemoteen thousand private schools. The aggregate of pupils is about three millions. The budget for primary education is nearly two and a half millions of francs.

Both chambers have agreed to the appropriation of three hundred thousand francs for the publication, under ministerial auspices, of the work of Botta and Flandin, on the remains discovered on the site of the ancient Nineveh. It was reported, and chiefly advocated in the chamber of deputies, by the Jewish deputy and lawyer, Cremieux, who said: "Luckily, this is a matter of rivalry between France and England; British consuls and artists have been digging, and are preparing a similar work you cannot refuse." The argument prevailed at once.

I know not to whom I am beholden for the sketch of the Life, Character, and Writings of the late John Pickering, of Salem, contained in the Boston Daily Advertiser of the 10th June. For me it was both welcome and melancholy; I honored the whole being of Mr. Pickering, and my duty will not be fulfilled until the sketch has passed into the hands of some member of the French Institute, by whom it may be used for that body. America possessed few such scholars; his productions and name are of high repute and authority in this meridian. The learned world that appreciated the savant should know what the man was-how worthy of equal esteem and regret. It is only a few months since I received

rated as precious and exact. A member of the French mission to China contributes to this bulletin a minute description of the island of Basilan, the largest of the Solo or Holo groupe, and he represents it to be superior in soil, climate, products, and commercial facilities to any other of the Archipelago. The London Morning Chronicle of the 26th ultimo dwells on the value, for Great Britain, of the island of Labuan, as a naval station or harbor of refuge. You may accept the first paragraph of the Chronicle's article of alarm:

"Events appear at length to be assuming a character in the Indian Archipelago which must command the attention of the British government. Every maritime power is actively at work there but ourselves. The Americans, hitherto, may perhaps be said to be only on the look-out; but the Dutch, whose position gives them many advantages, are proceeding with the utmost vigor and energy to appropriate to themselves all the commanding points, whether for commerce or for political influence. Their projected expedition against Bali will, if successful, give them an undoubted ascendency over a rich and fertile island, containing at least one million of inhabitants, and supplying the materials of a most lucrative trade. Other encroachments, still further east, are secretly contemplated by them-we mean against the native chiefs, who have neither injured nor molested them."

Viscount Victor Hugo pronounced a magnilo- | mission of Mr. Hood for a compromise. The quent exhortation to the government to endeavor crops of every description in France are likely to at once to repair and arrest the ravages of the seas be excellent. Nothing fresh from the new pope. on the French coasts, especially northward and in Portugal a chaos; Spain, volcanic; Germany, the channel. They are changing, with grievous progressive; Poland, subdued; Switzerland, disdamage, the whole configuration. Banks, houses, tracted; Italy, quiet, though malcontent. Sir villages are washed away. Here and there a Robert Peel has left an arduous programme for his lonely church shows only the steeple and upper successors. windows. From the mouth of the Somme to that of the Seine, the devastation is dreadful. Havre THE case of Count Léon against the Countess and other ports, Dieppe above all, may soon be de Luxbourg was heard again by the civil tribunal ruinously invaded. The fishermen are driven off. of the Seine. The circumstances of this case A peer wished to know how the Mediterranean must be fresh in the memory of most of our readcould be prevented from receding, as it does, from ers. It may not be amiss, however, to briefly the French shores; as the ocean from Newfound-retrace some of the leading points. Count Léon land. Within the ten years past the French gov- is the reputed son of Napoleon by the Countess de ernment has appropriated about a hundred and Luxbourg, formerly Mme. Denuelle de la Plaigne. fifty-six millions of francs to the improvement He was provided for and educated by direction of (amelioration) of the maritime ports. the late emperor, and a considerable sum of money was invested to create an annual income for his support. The count, having expended his property, applied to his reputed mother for the means of subsistence, and, not meeting with success, he brought an action against her to compel her to allow him 6,000fr. annually. This has been resisted chiefly on the ground that there was no proof of his being the son of the countess.

The

Of the proceedings on Thursday, the most interesting part was, first, a harangue of one of the bureaus of the Free Trade Society, on the wisdom of a revision and modification of the French tariffs, in which I mark these sentences: "Remember the admirable preambles to the ordinances of our kings on liberty of trade in grain. That of 1774, which embraces all the elements of the great doctrines of Adam Smith, preceded by two years the first pub-count, therefore, has since brought forward a numlication of his work, the Wealth of Nations, that ber of documents to show that he is the son of has served as a text for the repeal of the British Napoleon, and that the Countess de Luxbourg is corn laws. Gentlemen, let us restore to our coun- really his mother. Amongst the papers produced try what belongs to her; let no one of her glories by M. Crémieux, his counsel, was a letter written expire by non-assertion." The other important to the count in 1845, by the Prince Canino, brocontribution to the debate was from the Baron de ther of the Emperor Napoleon, in which he speaks Bourgoing, Minister of France for one of the Ger- of the count as his relation, with an enclosure, man kingdoms, who related how the troops for the being a letter of recommendation from the prince suppression of the Polish insurgents were sent by to a female cousin, in which he calls the count his the railroads, proving the facility of conveying any nephew. The court declared that the defendant number of all arms, with the utmost despatch. was the mother of the plaintiff, and adjudged her Seven hundred infantry were placed in twenty-to make him a provision of 4,000fr. pendente lite, three cars in five minutes, and travelled six leagues reserving the question of 6,000fr. per annum dethe hour. manded by the count.

July 4.

Enclosed are eight pages, de omnibus rebus, written at Versailles, yesterday and the day before, in my early morning leisure. At this moment the weather is too hot for the preparation of a formal epistle. What remains in my note-book of bistorical and political interest you shall have by the steamer of the 19th instant. Let me offer you the compliments of the glorious anniversary. Our country has never had stronger motive or ampler reason to rejoice in its independence and growth. The Americans in this capital are, I believe, all satisfied with the terms of the Oregon convention. The Paris writers decide that our government has achieved, on the whole, a capital bargain. All the London organs profess to be more or less content. The Paris papers of this morning furnish no comments on American matters. I must except the Siècle, which repeats that Lord Cowley returned in all haste from London to arrange a joint mediation in behalf of Mexico. As Russia has considerable interests on the Pacific coast, she is solicited to unite in guarantying the Mexican territory. If the Czar should consent, Mr. Guizot will adhere, and the three powers then proclaim a European concert for the maintenance of the American equipoise. No disquisition yet in the Debats on the Oregon adjustment. The British and French cabinets are understood to have grown sick of the La Plata mediation, and to rely on the

THE Minister of the Marine, convinced of the advantages of the galvanization of iron, has ordered a 20-gun brig and another vessel, now being built of iron at Brest, to be subjected to this process.

A LETTER from Vienna states that M. Negrelli, few days to examine the line marked down by the inspector-in-chief of railways, was to set out in a engineer for the Great Gallician Railway, which is be about 350 English miles. to be commenced in the spring. Its length is to

THE Coronation of Oscar I. and his consort Eugenia, daughter of Prince Eugene de Beauharnais, as King and Queen of Norway, is fixed to be held on the 15th October next, on which occasion the Storthing will be convoked.

THE quarantine question will be seriously discussed among the other important inquiries to be entered upon at the meeting of the Scientific Congress of Italy.

THE Chambers of Commerce are about to be

called upon to examine the propriety and advantages of establishing a French factory at Canton, with branch offices of agency at Macao, Manilla, and Java.

THE France says: "We are able to state that, in September next, there will be a meeting of the three sovereigns of Russia, Prussia, and Austria, at Vienna."

LITTELL'S LIVING AGE.-No. 119.-22 AUGUST, 1846.

From the Edinburgh New Philosophical Journal.
ARAGO ON THE WEATHER.

repeat, that the readers of the Annuaire ought not to expect to find here a complete investigation of the problem which I have taken up. My sole Is it possible, in the present state of our knowledge, intention is to lay before them a few facts, which, to foretell what Weather it will be at a given time taken in connexion with those which I shall anaand place? Have we reason, at all events, to ex-lyze in a second notice, appear to me to lead to pect that this problem will one day be solved? By this conclusion. M. ARAGO, Perpetual Secretary of the French Academy of Sciences, &c. &c.

ENGAGED as I am, both from inclination and duty, in meteorological studies, I have often asked myself if we should ever be able, by a reference to astronomical considerations, to determine, a year in advance, what shall be the state, in a given place, of the annual temperature, the temperature of each month, the quantities of rain compared with the ordinary mean, the prevailing winds, &c. I have already laid before the readers of the Annuaire the results of the investigations undertaken by natural philosophers and astronomers, regarding the influence of the moon and of comets on the changes of the weather. These results clearly show, in my opinion, that the influences of both these bodies are almost insensible, and, therefore, that the prediction of the weather can never be a branch of astronomy, properly so called. And yet our satellite and comets have, at all periods, been considered as preponderating stars in meteorology.

BETWEEN WHAT LIMITS THE MEAN TEMPERATURES
OF YEARS AND MONTHS VARY IN OUR CLIMATES.

The meteorological state of a given place, is much less variable than those would be led to believe who judge of it by their personal sensations, by vague recollections, or the condition of the crops. Thus, at Paris, the mean temperature of years ranges within very narrow limits.

The annual mean temperature of Paris, from 1806 to 1826 inclusive, has been +10°-8 centigrade, (54°-4 Fahr.) The greatest of 21 annual means does not exceed the general mean by more than 10.3, (20.3 F.;) the lowest of the mean annual temperatures has been found below the general mean only by 104, (20-5 F.) As far as relates to mean annual temperatures, systematic meteorologists have, therefore, no need of foresight to predict only slight perturbations. The causes of disturbance will satisfy all the phenomena, if they can produce, more or less, 1°.5 of centigrade variation, (207 F.)

It is not the same with regard to the months. The differences between the general means and the partial means extend, in January and December, to 4 and 5 centigrade degrees, (7° to 9° F.)

Since the publication of these opinions, I have regarded the problem in another aspect. I have considered whether the operations of man, and occurrences which will always remain beyond the range of our foresight, might not be of such a nature as to modify climates accidentally, and in a from indulging in any illusion on this subject. Hundreds very sensible manner, in particular with regard to of persons who have gone through a regular course of temperature. I already perceive that facts will university studies, will not fail, in 1846, as they had done answer in the affirmative. I should have wished, following, which it is truly pitiable to hear in the present on former occasions, to ply me with such questions as the however, not to publish this result till after I had day: Will the winter be severe? Think you that we finished my investigations; but I must frankly own, shall have a warm summer, a humid autumn? This is that I wished to have an opportunity of protesting a very long and destructive drought; do you think it is decidedly against the predictions which have every produce great mischief this season-what is your opinnear an end? People think that the April moon will year been attributed to me, both in France and in on? &c. &c. In spite of the little confidence I have in other countries. Never has a word escaped my predictions, I affirm that in this case the event will not lips, either in private or in the course which I have deceive me. Nay, for some years past have I not been delivered for upwards of thirty years; never has a put to a still severer proof? Has not a work been published, entitled "Lectures on Astronomy, delivered at the line published with my consent, authorized any one Observatory by M. Arago, collected by one of his Pupils ?" to imagine it to be my opinion that it is possible, I have protested a dozen times against this work; I have in the present state of our knowledge, to announce, shown that it swarins with inconceivable errors; that it with any degree of certainty, what weather it will is beneath all criticism whenever the author ceases to embe a year, a month, a week, I shall even add, a ploy his scissors on the notices of the Annuaire, and is reduced to the necessity of drawing a few lines from his single day, in advance. May the indignation I own resources. Vain efforts! These pretended Lectures have felt at seeing a multitude of ridiculous predic-on Astronomy at the Observatory have, however, reached tions appear under my name, not constrain me, by no less than a fourth edition. The laws have made no the force of reaction, to give an exaggerated de- provision against what I shall call this scientific calumny. gree of importance to the disturbing causes I have What must be done when the law is silent? Subunit with resignation? A sensitiveness which will not appear surenumerated! At present, I believe that I am in a prising to any who have seen the book in question, will condition to deduce from my investigations the im- not allow me to be satisfied with resignation. My posiportant result which I now announce; Whatever tion having become intolerable, I have made up my mind may be the progress of sciences, NEVER will observers to publish myself the Lectures which have been so outwho are trust-worthy, and careful of their reputa- shall abandon for a time the plans for original investiga rageously disfigured. Since it has become necessary, I tion, venture to foretell the state of the weather.* tions which I had formed, and devote the time I wished to employ in delicate experiments, fitted to illustrate points of the science still enveloped in great obscurity, to the preparation of a work intended to popularize astronomy. May this work be in some degree useful.

*This explicit declaration may give me a right to expect that I shall no longer be compelled to play the part of Nostradamus or Mathew Lænsberg; but I ain far

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In consequence of these variations, if we compare the extreme temperatures of each month with the mean or normal temperatures of all the rest, we shall find:

That the month of January is sometimes as temperate as the mean of the month of March.

That the month of February sometimes resembles the mean second fortnight of April, or the mean first fortnight of January.

That the month of March sometimes resembles the mean of the month of April, or the mean of the second fortnight of January.

That the month of April never reaches the temperature of the month of May.

That the month of May is pretty frequently, in the mean, warmer than certain months of June. That the month of June is sometimes, in the mean, warmer than certain months of July.

That the month of July is sometimes, in the mean, warmer than certain months of August.

climates, is that known by the English name of
icebergs. These mountains of ice come from the
glaciers, properly so called, of Spitzbergen or the
shores of Baffin's Bay. They detach themselves
from the general mass, with a noise like that of
thunder, when the waves have undermined their
base, and when the rapid congelation of rain-water in
their fissures produces a sufficient expansion to move
these huge masses and push them forward.
causes, and such effects, will always remain beyond
the range of human foresight.

Such

Those who remember the recommendations which the guides never fail to give upon approaching certain walls of ice, and the huge masses of snow placed upon the inclined ridges of the Alps; those who have not forgotten that, according to the affirmations of these experienced men, the report of a pistol, or even a mere shout, may produce frightful catastrophes, will agree in the opinion I have just expressed.

Icebergs often descend without melting, even to

That the month of August is sometimes, in the mean, slightly colder than certain months of Sep-pretty low latitudes. They sometimes cover imtember.

That the month of September is sometimes, in the mean, colder than certain months of October. That the month of October may be, in the mean, nearly 30 (50.4 F.) colder than certain months of November.

That the month of November may be, in the mean, about 50.5 (about 10° F.) colder than the warmest months of December.

That the month of December may be, in the mean, 7° (12°.6 F.) colder than the month of Jan

uary.

mense spaces; we may therefore suppose that they sensibly disturb the temperature of certain zones of the oceanic temperature, and then, by means of communication, the temperature of islands and continents. A few instances of this will not be out of place.

On the 4th October, 1817, in the Atlantic Ocean, 46° 30 north latitude, Captain Beaufort fell in with icebergs advancing southwards.

On the 19th January, 1818, on the west of Greenspond, in Newfoundland, Captain Daymont met with floating islands. On the following day, the vessel was so beset with ice that no outlet

DISTURBING CAUSES OF TERRESTRIAL TEMPERATURE could be seen even from the top-masts. The ice,

WHICH CANNOT BE FORESEEN.

for the most part, rose about 14 English feet above the water. The vessel was carried southwards in this manner for twenty-nine days. It disengaged itself in 44° 37′ latitude, 120 leagues east of Cape Race. During this singular imprisonment, Captain Daymont noticed upwards of a hundred icebergs.

The atmosphere which, on a given day, rests upon the sea, becomes in a short time, in mean Jatitudes, the atmosphere of continents, chiefly from the prevalence of westerly winds. The atmosphere derives its temperature, in a great measure, from that of the solid or liquid bodies which it envelops. Everything, therefore, which modi- On the 28th March, 1818, in 41° 50′ north latitude, fies the normal temperature of the sea, produces, 53° 13′ longitude west of Paris, Captain Vivian sooner or later, perturbations in the temperature of felt, during the whole day, an excessively cold continental atmospheres. Are those causes, which wind blowing from the north, which led him to may sensibly modify the temperature of a considera- suppose that ice was approaching. And, in fact, ble portion of the ocean, placed forever beyond the on the following day, he saw a multitude of floatforesight of man? This problem is closely con- ing islands, which occupied a space of upwards of nected with the meteorological question I have un- seven leagues. "Many of these islands," says he, dertaken to consider. Let us endeavor to find the" were from 200 to 250 English feet high above solution of it.

No one can doubt that the ice-fields of the Arctic pole-the immense frozen seas-exert a marked influence on the climates of Europe. In order to appreciate in numbers the importance of this influence, it would be necessary to take into account at ence the extent and position of these fields; but these two elements are so variable that they cannot be brought under any certain rule.

The eastern coast of Greenland was in former times accessible and well peopled. All of a sudden an impenetrable barrier of ice interposed itself between it and Europe. For many ages Greenland could not be visited. About the year 1815 this ice underwent an extraordinary breaking up, became scattered in a southerly direction, and left the coast free for many degrees of latitude. Who could ever predict that such a dislocation of the fields of ice would take place in such a year rather than in another?

The floating ice which ought to act most on our

the water."

The brig Funchal, from Greenock, met with fields of ice on two different occasions, in her passage from St. John's, Newfoundland, to Scotland; first on the 17th January, 1818, at the distance of six leagues from the port she had left; and afterwards, in the same month, in latitude 47° 30'. The first field was upwards of three leagues broad, and its limit in a northern direction could not be seen. The second, likewise very extensive, had an immense iceberg in its centre.

On the 30th March, 1818, a sloop of war, The Fly, passed between two large islands of floating ice in 42 degrees of north latitude.

On 2d April, 1818, Lieutenant Parry met with icebergs in 42° 20′ of north latitude.

This year (1845) the English vessel Rochefort continued enclosed, at the end of April and beginning of May, for twenty-one consecutive days, in a mass of floating ice, which ran along the bank of Newfoundland, advancing to the south.

Maximum. Minimum

and 3 days after the solstice. 46 and 18 days after

The sea is much less easily heated than the land, | minima temperatures in different places. The foland that, in a great measure, because the water is lowing are some of these results:diaphanous. Everything, therefore, which causes this diaphaneity to vary considerably, will produce sensible changes in the temperature of the sea, immediately after in the temperature of the oceanic atmosphere, and, somewhat later, in the temperature of the continental atmosphere. Do causes exist, independently of what science discovers to us, which may interfere with the transparency of the sea to a great extent? Let the following be my answer:

Mr. Scoresby has shown, that, in northern regions, the sea sometimes assumes a very decided olive-green color; that this tint is owing to medusæ and other minute animalcule; and that wherever the green color prevails the water possesses very little diaphaneity.

Mr. Scoresby occasionally met with green bands, which were from two to three degrees of latitude (60 to 80 leagues) in length, and from 10 to 15 leagues broad. The currents convey these bands from one region to another. We must suppose that these do not always exist; for Captain Phipps, in the account of his voyage to Spitzbergen, makes no mention of them.

As I have just stated, the green and opaque portions of the sea must become heated in a manner different from the diaphanous parts. This is a cause of variation in the temperature which can never be subjected to calculation. We can never know beforehand whether, in such and such a year, these countless myriads of animalcule will be more or less prolific, and what will be the direction of their migration southwards.

The phosphorescence of the sea is owing to minute animals of the medusa kind. The phosphorescent regions occupy very large spaces-sometimes in one latitude, sometimes in another. Now, as the water of the phosphorescent spaces is quite turbid, and as its diaphaneity is almost entirely destroyed, it may become, by its abnormal heating, a cause of notable disturbance in the temperature of the oceanic and continental atmospheres. Who can foresee the intensity of this cause of thermic variation? who can ever know beforehand the place which it occupies?

Let us suppose the atmosphere immobile and perfectly clear. Let us suppose, moreover, that the soil has everywhere, in an equal degree, absorbing and emissive properties, and the same capacity for heat; we should then observe throughout the year, as the effect of solar action, a regular and uninterrupted series of increasing temperatures, and a corresponding series of decreasing temperatures. Each day would have its invariable temperature. Under every determined parallel, the days of the maximum and minimum of heat would be respectively the same.

This regular and hypothetical order is disturbed by the mobility of the atmosphere; by clouds more or less extensive, and more or less permanent; and by the diverse properties of the ground. Hence the elevations or depressions of the normal heat of days, months, and years. As disturbing causes do not act in the same way in every place, we may expect to see the primitive figures differently modified; to find comparative inequalities of temperature where, from the nature of things, the most perfect equality might have been looked for.

Nothing is better calculated to show the extent of these combined disturbing causes, than the comparison of mean epochs, indicating the maxima and

24th Dec. 51

6th Aug.

Sth Jan.

1st Aug.

3d Jan.

22d July.

8th Jan.

15th July.

14th Jan.

St.Gothard, 11th Aug. (10 years,) Rome, (10 years.) Jena, (18 years.) Petersburg, (10 years.) Paris, (21 years.)

the solstice.

S41 and 14 days after the solstice.

31 and 18 days after

the solstice. 25 and 25 days after the solstice.

These differences belong to the localities. But when concealed local circumstances exert so much influence, is it not natural to think that the modifications which they receive from the hand of man may sensibly alter, in the interval of a few years, the meteorological type of every town in Europe?

I have shown that local circumstances which are latent, or at least faintly characterized, may exert sensible and constant influences on the manner in which the maxima and minima of temperature are distributed in the year. When science shall be put in possession of exact and comparable meteorological observations, made simultaneously in different places; when these observations shall be scrupulously and judiciously digested, we shall very probably find that circumstances of locality will occupy a much more prominent place in science than natural philosophers seem now disposed to attribute to them. It would not be difficult for me, at this moment, to mention circumscribed districts which have completely escaped the severe colds to which the surrounding countries were subjected. The Sables d'Olonne, for example, and the neighboring districts, six leagues in circuit, formed, during the winter of 1763 and 1764, a kind of thermal oasis. The Loire was frozen near its mouth; an intense cold of -10 degrees centigrade (14° F.) interrupted all agricultural operations in the districts which the river traverses. In the Sables the weather was mild: this little canton escaped the frost.

The following is a still more extraordinary fact than the preceding, for it takes place every year.

There is in Siberia, M. Erman has informed us, an entire district, in which, during the winter, the sky is constantly clear, and where a single particle of snow never falls.

I am willing to overlook the perturbations of the terrestrial temperatures which may be connected with a greater or less abundant emission of light or solar heat, whether these variations of emission depend on the number of spots which are found accidentally scattered over the sun's surface, or whether they originate in some other unknown cause; but it is impossible for me not to draw the reader's attention to the obscurations to which our atmosphere is from time to time subject, without any assignable rule. These obscurations, by preventing the light and solar heat from reaching the earth, must disturb considerably the course of the seasons.

Our atmosphere is often occupied, over spaces of considerable extent, by substances which materially interfere with its transparency. These matters sometimes proceed from volcanoes in a state of eruption. Witness the immense column of ashes which, in the year 1812, after having been projected from the crater of the island St. Vincent to a great height, caused at mid-day a darkness like that of night in the island of Barbadoes.

These clouds of dust appear, from time to time

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