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In consequence of these variations, if we com-climates, is that known by the English name of pare the extreme temperatures of each month with icebergs. These mountains of ice come from the the mean or normal temperatures of all the rest, we glaciers, properly so called, of Spitzbergen or the shall find :

shores of Baffin's Bay. They detach themselves That the month of January is sometimes as tem- from the general mass, with a noire like that of perate as the mean of the month of March,

thunder, when the waves have undermined their That the month of February sometimes resem-base, and when the rapid congelation of rain-water in bles the mean second fortnight of April, or the their fissures produces a sufficient expansion to move mean first fortnight of January

these huge masses and push them forward. Soeh That the month of March sometimes resembles causes, and such effects, will always remain beyond the mean of the month of April, or the mean of the the range of human foresight. second fortnight of January.

Those who remember the recommendations That the month of April never reaches the tem- which the guides never fail to give upon approachperature of the month of May.

ing certain walls of ice, and the huge masses of That the month of May is pretty frequently, in snow placed upon the inclined ridges of the Alps : the mean, warmer than certain months of June. those who have not forgotten that, according to the

That the month of June is sometimes, in the affirmations of these experienced men, the report mean, warmer than certain months of July. of a pistol, or even a mere shout, may prodoce

That the month of July is sometimes, in the frightful catastrophes, will agree in the opinion I mean, warmer than certain months of August. have just expressed.

That the month of August is sometimes, in the Icebergs often descend without melting, even to mean, slightly colder than certain months of Sep- pretty low latitudes. They sometimes cover imtember.

mense spaces; we may therefore suppose that That the month of September is sometimes, in they sensibly disturb the temperature of certain the mean, colder than certain months of October. zones of the oceanic temperature, and then, by

That the month of October may be, in the mean, means of communication, the temperature of nearly 3o (5°4 F.) colder than certain months of islands and continents. A few instances of this November.

will not be out of place. That the month of November may be, in the On the 4th October, 1817, in the Atlantic Ocean, mean, about 50.5 (about 10° F.) colder than the 46° 30 north latitude, Captain Beaufort fell in with warmest months of December.

icebergs advancing southwards. That the month of December may be, in the On the 19th January, 1818, on the west of mean, 70 (120.6 F.) colder than the month of Jan-Greenspond, in Newfoundland, Captain Daymont uary.

met with floating islands. On the following day,

the vessel was so beset with ice that no outlet DISTURBING CASES 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 atmosphere which, on a given day, rests the water. The vessel was carried southwards upon the sea, becomes in a short time, in mean in this manner for twenty-nine days. It diseplatitudes, the atmosphere of continents, chiefly gaged itself in 41° 37' latitude, 120 leagues east from the prevalence of westerly winds. The at- of Cape Race. During this singular imprisonment, mosphere derives its temperature, in a great mea- Captain Daymont noticed upwards of a hundred sure, from that of the solid or liquid bodies which icebergs. 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 floarforesight of man? This problem is closely con- ing islands, which occupied a space of upwards of nected with the meteorological question I have on- seven leagues. * Many of these islands," says be. dertaken to consider. Let us endeavor to find the " were from 200 to 250 English feet high above solution of it.

the water." No one can doubt that the ice-fields of the Arc- The brig Funchal, from Greenock, met with tic pole-the immense frozen seas-exert a marked fields of ice on two different occasions, in ber pas influence on the climates of Europe. In order to sage from St. John's, Newfoundland, to Scouand : appreciate in numbers the importance of this influ- first on the 17th January, 1818, at the distance of ence, it would be necessary to take into account at six leagues from the port she had left; and afteronce the extent and position of these fields; but wards, in the same month, in latitude 47° 30'. these two elements are so variable that they can- The first field was upwards of three leagur net be brought under any certain rule.

broad, and its limit in a northern direction orold The eastern coast of Greenland was in former not be seen. The second, likewise very extensive, times accessible and well peopled. All of a sud- had an immense iceberg in its centre. den an impenetrable barrier of ice interposed itself On the 30th March, 1818, a sloop of war, The between it and Earope. For many ages Green- Fly, passed between two large islands of floating land could not be visited. About the year 1815 ice in 42 degrees of north latitude. this ice underwent an extraordinary breaking up, On 20 April, 1818, Lieutenant Parry met with became scattered in a southerly direction, and left icebergs in 42° 20 of north latitude. the coast free for many degrees of latitude. Who This year (1815) the English vessel Rochefort could ever predict that such a dislocation of the continued enclosed, at the end of April and begin. fields of ice would take place in such a year rather ning of May, for twenty-one consecutive days, in than in another?

a mass of floating ice, which ran along the bank The floating ice which ought to act most on our of Newfoundland, advancing to the south.

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

Maximum. Minimum, this diaphaneity to vary considerably, will produce St. Gothard, 2

24th Dec. § 51 and 3 days after sensible changes in the temperature of the sea, (10 years,) 3 ne temperature of the sea. I (10 years.' Th Aug.

El the solstice. immediately after in the temperature of the oceanic

Rome,

och tons 46 and 18 days after (10 years.)

{6th Aug. sth Jan. 3 the solstice. atmosphere, and, somewhat later, in the tempera

Jena, ture of the continental atmosphere. Do causes

{1st Aug. 3d Jan. (18 years.) S

S 41 and 14 days after

the solstice. exist, independently of what science discovers to

Petersburg,
Petersburg, 1990 buy

22d July

geh lon us, which may interfere with the transparency of

Š 31 and 18 days after (10 years.) 34

8th Jan. 3 the solstice. the sea to a great extent? Let the following be Paris, Loh

>15th July.

uh To (21 years.) )

S 25 and 25 days after 14th Jan. 24

: the solstice. my answer:

Mr. Scoresby has shown, that, in northern re- These differences belong to the localities. But gions, the sea sometimes assumes a very decided when concealed local circumstances exert so much olive-green color ; that this tint is owing to medusæ influence, is it not natural 10 think that the modifiand other minute animalculæ ; and that wherever | cations which they receive from the hand of man the green color prevails the water possesses very may sensibly alter, in the interval of a few years, little diaphaneity.

the meteorological type of every town in Europe? Mr. Scoresby occasionally met with green bands, I have shown that local circuinstances which are which were from two to three degrees of latitude latent, or at least faintly characterized, may exert (60 to 80 leagues) in length, and from 10 to 15 sensible and constant influences on the manner in leagues broad. The currents convey these bands which the maxima and minima of temperature are from one region to another. We must suppose distributed in the year. When science shall be that these do not always exist ; for Captain Phipps, put in possession of exact and comparable meteorin the account of his voyage to Spitzbergen, makes ological observations, made simultaneously in differno mention of them.

ent places; when these observations shall be scruAs I have just stated, the green and opaque pulously and judiciously digested, we shall very portions of the sea must become heated in a manner probably find that circumstances of locality will different from the diaphanous parts. This is a cause occupy a much more prominent place in science of variation in the temperature which can never be than natural philosophers seem now disposed to subjected to calculation. We can never know attribute to them. It would not be difficult for me, beforehand whether, in such and such a year, these at this moment, to mention circumscribed districts countless myriads of animalcule will be more or which have completely escaped the severe colds less prolific, and what will be the direction of their to which the surrounding countries were subjected. migration southwards.

The Sables d'Olonne, for example, and the neighThe phosphorescence of the sea is owing to mi-boring districts, six leagues in circuit, formed, note animals of the medusa kind. The phospho- during the winter of 1763 and 1764, a kind of rescent regions occupy very large spaces--some- thermal oasis. The Loire was frozen near its times in one latitude, sometimes in another. Now, mouth; an intense cold of —10 degrees centigrade as the water of the phosphorescent spaces is quite (14° F.) interrupted all agricultural operations in turbid, and as its diaphaneity is almost entirely the districts which the river traverses. In the destroyed, it may become, by its abnormal heating, Sables the weather was mild: this little canton a cause of notable disturbance in the temperature escaped the frost. . of the oceanic and continental atmospheres. Who The following is a still more extraordinary fact can foresee the intensity of this cause of thermic than the preceding, for it takes place every year. variation? who can ever know beforehand the There is in Siberia, M. Erman has informed us, place which it occupies ?

an entire district, in which, during the winter, the Let us suppose the atmosphere immobile and sky is constantly clear, and where a single particle perfectly clear. Let us suppose, moreover, that of snow never falls. the soil has everywhere, in an equal degree, ab- I am willing to overlook the perturbations of the sorbing and emissive properties, and the same terrestrial temperatures which may be connected capacity for heat; we should then observe through with a greater or less abundant emission of light or out the year, as the effect of solar action, a regular solar heat, whether these variations of emission and aninterrupted series of increasing temperatures, depend on the number of spots which are found and a corresponding series of decreasing tempera- accidentally scattered over the sun's surface, or tares. Each day would have its invariable tem- whether they originate in some other unknown peratore. Under erery determined parallel, the days cause ; but it is impossible for me not to draw the of the maximum and minimum of heat would be reader's attention to the obscurations to which our respectively the same.

atinosphere is from time to time subject, without This regular and hypothetical order is disturbed any assignable rule. These obscurations, by preby the mobility of the atmosphere ; by clouds more venting the light and solar heat from reaching the or less extensive, and more or less permanent; earth, must disturb considerably the course of the and by the diverse properties of the ground. Hence seasons. the elevations or depressions of the normal heat of Our atmosphere is often occupied, over spaces days, months, and years. As disturbing causes of considerable extent, by substances which mate. do not act in the same way in every place, we may rially interfere with its transparency. These mai. expect to see the primitive figures differently mod. ters sometimes proceed from volcanoes in a state ified ; to find comparative inequalities of tempera- | of eruption. Witness the immense column of ture where, from the nature of things, the most ashes which, in the year 1812, after having been perfect equality might have been looked for. projected from the crater of the island St. Vincent

Nothing is better calculated to show the extent to a great height, caused at mid-day a darkness of these combined disturbing causes, than the com- like that of night in the island of Barbadoes. parison of mean epochs, indicating the maxima and These clouds of dust appear, fr m time to time

in regions where no volcano exists. Canada, in the manufacturer of almanacs ooght, therefore, to particular, is subject to such phenomena. In that enter into a correspondence with all the wood-cutcountry recourse has been had, for an explanation, ters of every country. to the burning of forests. The facts do not always In North America, the interior of the continent appear to agree exactly with this supposition. does not enjoy, in the same latitudes, the same cliThus, on 16th October, 1785, at Quebec, clouds of mate as the coasts. By the influence of lakes, this such obscurity covered the sky, that it was impos- difference disappears with respect to all the points sible, even at noon, to see in what direction one where the distance from these great masses of was going. These clouds covered a space of 120 water is not considerable. leagues in length by 80 broad. They seemed to We must, therefore, expect that the drying up come from Labrador, a country very thinly wood- of a lake will modify the climate of the neighbor ed; and they presented none of the characters of ing region ; and that a vast inundation, arising smoke.

from the unexpected rupture of a barrier, will proOn the 28 July, 1814, clouds similar to the above duce for a time an opposite effect. surrounded some vessels in the open sea on their If any one should exclaim against me on seeing way to the River St. Lawrence. The great ob- me register causes, each of which, taken by itself, scurity lasted from the evening of the 2d till the does not seem capable of producing a very great afternoon of the 3d.

effect, my reply would be-We have to consider With regard to the object we have here in view, an influence as a whole, and in every case the it is of little importance whether we ascribe these perturbations which it is our object to explain, clouds, capable as they are of completely obstruct are far from being so extensive as the public strping the solar rays, to the burning of forests and poses. savannas, or to emanations from the earth. Their According to Howard, the mean temperature of formation, and their arrival in a given place, will London erceeds that of the neighboring country, remain equally beyond the predictions of science; about a centigrade degree (1o.8 €) the variations of temperature, and meteors of every The difference between the two temperatures is kind which may be caused by these clouds, will not the same at all seasons. never be pointed out beforehand in our meteorological almanacs.

ELECTRICITY. The accidental darkening of the air, in 1783, We could not well avoid arranging electricity embraced so extensive a space, (from Lapland to among the causes which have a striking influence Africa,) that it was ascribed to the matter belong-on climatological phenomena. Let us go farther, ing to the tail of a comet, which, it was alleged, and inquire whether the operations of man may had mingled with our atmosphere. It is out of disturb the electrical state of an entire country. the question to maintain that an accidental state of Clearing the wood from a mountain is the dethe atmosphere, which enabled us, for a period of struction of a number of lightning-conductors nearly two months, to look at the sun at mid-day equal to the number of trees felled; it is the modiwith the naked eye, was without influence on ter- fication of the electrical state of an entire country : restrial temperatures.

the accumulation of one of those elements indisForests cannot fail to exercise a sensible infla- pensable to the formation of hail, in a locality ence on the temperature of the surrounding where, previously, this element was dissipated by regions ; because, for example, snow remains the silent and incessant action of the trees. On there for a much longer time than in the open this point, observations support theoretical decountry. The destruction of forests, therefore, ductions. ought to produce a modification in our climates. According to a detailed statistical account, the

In given instances, what is the precise influence losses occasioned by hail in the continental states of forests, estimated by the centigrade thermome of the king of Sardinia, from 1820 to 128 incloter? The question is very complicated, and has sively, amount to the sum of forty-sir millions of not hitherto been solred.

| francs. Three provinces, those of Val d'Aoste, In all very mountainous regions, the valleys are the Vallée de Suze, and Haute Maurienne, do not traversed by periodical diurnal breezes, particularly appear in these tables; they were not visited with sensible in May, June, July, August, and Septem-hail storms. The mountains of these three prorunber. These breezes ascend ihe valleys, from ces are the best wooded. seven or eight o'clock in the morning to three or of the warmest provinces, that of Genoa, the four in the afternoon, the time when they reach mountains of which are well covered, is scarcely their greatest force, and from four o'clock to six or ever visited by this meteor. seven in the evening. For the most part they Atmospheric electricity gives rise to phenomena, blow with the force of a decided wind, and some which are immense from their extent. They times with that of a violent wind; they must, seem, however, to owe their origin to canses therefore, exert a sensible influence on the cli- purely local. Their propagation likewise takes mates of the countries which lie around these place under circumscribed influences, in particular valleys.

zones, and these sometimes rather narrow. What is the cause of these breezes ! Every- On the 13th July, 1788, in the morning, a hailthing concurs to show that the cause is to be found storm commenced in the south of France, traversed. in the manner in which the solar rays warm the in a few hours, the whole length of the kingdom, central mass whence these valleys radiate. Sup- and thence extended to the low countries and Holpose this mass to be naked, then you have a cer- land. tain effect; substitute tufted forests for arid rocks, All the districts in France injured by the hail, and the phenomenon will assume another charac- were situated in two parallel bands, running ter, at least with regard to intensity.

south-west and north-east. One of these bands This is one of the twenty ways in which the was 175 leagues long; the other about 200. clearing of woods affects climates. Before putting The mean breadth of the most western hail his hand to the task of arranging his predictions, band was 4 leagues, the other only 2 leagues. Ou

the space between these two bands, rain only fell ; I quakes is exerted only in the vicinity of the equaits mean breadth was 5 leagues. The storm tor. The power of predicting rain must, theremoved from the south to the north with a rapidity fore, suppose an anticipatory knowledge of the of about 16 leagues an hour.

number and strength of the shocks, which are The damage occasioned in France, in the 1039 to be felt in the region for which the astrologer parishes visited by the hail, appeared, from official works. inquiry, to amount to twenty-five millions (one The following passage occurs in Bacon's works: million sterling.)

-“Some historians allege that, at the time when This, certainly, must be regarded as a con- Guyenne was still in the power of the English, the siderable atmospheric commotion, whether we inhabitants of Bordeaux and the neighboring canregard the material devastation it produced, or the tons made a request to the king of England, to influence which the displacement of the air, and induce him to prevent his subjects of the counties the mass of hail deposited on the surface of two of Sussex and Hampton, from burning the heaths long and broad bands of country, must have exer- in the end of April, as they usually did ; becised on the normal temperature of a great number cause they thereby gave rise, it was affirmed, of places. Could meteorologists, however skilled, to a wind which proved very hurtful to their have been able to foresee it?

vines." The origin of the two bands was in the district I know not how far there were grounds for this of Aunis, and in Saintonge. Why there, and not request, as the distance of Bordeaux from the elsewhere? Why did not the storm commence at county of Sussex is very considerable ; but I must another point of the parallel of latitude, passing by not fail to mention, that natural philosophers are its meridional extremities? Because, it will be now disposed to assign a no less extraordinary answered, in Aunis and in Saintonge, on the 13th part lo conflagrations. In the United States, a July, 1788, the conditions of electricity and tem- well known philosopher, M. Espy, adopting the perature were eminently favorable for the produc- opinions prevalent among the natives of the new tion of a hail-storm, and an accompanying hurri- continent, from Canada to Paraguay, has recently cane directed from the south-south-west to the proposed to produce, in times of drought, artificia. north-north-east. Admitted ; but were not these rains, and his means of doing so is by kindling thermal and electrical conditions favorable to the large fires.* In support of his scheme, M. Espy production of a storm, ultimately connected with mentions the following :agricultural operations, with the existence of such The opinion of the Indians of Paraguay, who, and such a mass of trees, with the state of irriga- according to the report of the missionaries, set fire tion, with circumstances varying according to the to vast savannas when their crops are threatened wants and caprice of men ? With regard to tem- with drought, and allege that they thus produce perature, no one can hesitate in his reply. In the even storms accompanied with thunder ; other particular, the connection will appear not The opinion of the colonists of Louisiana, and less evident if I bring to mind that evaporation is the success from time immemorial of burning the a fertile source of electricity, and that various prairies in that State ; natural philosophers have even included vegetation The opinion of the population of Nova Scotia, among the causes which generate this same fluid respecting the consequences of burning forests ; in the atmosphere.

The opinion and practice of the colonists of the If it be true, as has been alleged, that, in certain districts of Delaware and Otsego, &c., &c. cases, the flame and smoke which issue from the M. Espy says, that he has assured himself, in mouth of a furnace, or from the chimney of a various ways, that the climate of Manchester has manufactory, may deprive the atmosphere of all undergone gradual and sensible modifications, in electricity for many leagues around, ihe prophets proportion as manufacturing industry has inin meteorology, will be placed in an additional creased. Since that city has become, so to speak, difficuliy. It will be necessary that they should a vast furnace, it rains there more or less every day. know beforehand all the plans of the masters of Those who pretend that the deterioration of the forges and proprietors of manufactories.

climate is not so considerable, assure us that it According to all that we most certainly know does not rain at Manchester more than six days in respecting the physical cause of water-spouts, and the seven ! according to M. Espy's theory, sometimes no Suppose these facts to be as averred. The premore is necessary than an ascending current pro- dictions of rain, in a given place, will often he duced by the chimney of a manufactory, to give overturned by accidental fires, and by the fires of rise to one of these formidable meteors.

manufactories.

Space and time will not allow me to point out RAIN.

the multitude of local causes which may exercise It is said to have been remarked in Italy, that, a great influence on the direction and force of the in proportion as rice-fields multiply, the annual wind. I shall discuss this delicate question in quantity of rain has gradually increased, and that another notice. At present, I shall confine mythe number of rainy days has augmented in pro- self to a remark well-fitted to enlighten those who, portion.

from want of meteorological instruments, take for Can it be imagined, that such circumstances their guides the state of the crops and of vegetaas these can ever be taken into account, in the tion. It may be expressed in the following formucombinations of the almanac-manufacturers ?

la the tropical regions of America, the natives * It has long been an opinion entertained by the peasregard repeated shocks of earthquake, as welcome antry in the south of Scotland (we know not whether the precursors of fertilizing rains. Humboldt even belief prevails elsewhere,) thai muir-burn, or the burnrelates, that violent shocks suddenly brought on ling, in the spring, of old heather and other plants, in the rainy season, a considerable time before the

the order to produce a more tender and nutritious vegetation,

a practice which was once very general, has a decided ordinary period.

tendency to produce a change of weather, and to bring on It is not probable that the influence of earth- rain.--Ed.

lary; the wind exercises a direct action on vege- tom often presents elevated portions, arranged in tables, often very injurious, and which ought arcs of circles parallel to the external ridge; so to be carefully distinguished from climatological that the rings would seem to have been formed at action. It is against this direct action, that cur- the surface of a fluid mass on which scoriæ were tains of wood, by forming a shelter, are especially floating, by means of a circular undulation, whose useful.

amplitude went on diminishing. The direct influence of the wind, on the phe- The bottom of the great spots, such as the more nomena of vegetation, is nowhere more strikingly serenitatis, &c., exhibits the same characters. exemplified than in the Isle of France. The Simple spots are also to be noticed, or portions south-east wind, very healthy both for men and having no projection, but whose circular forms are animals, is, on the contrary, a perfect scourge to well marked. It cannot, therefore, be called in the trees. Fruit is never found on the branches question, that a general cause, producing these cirdirectly exposed to this wind ; none is to be found cular forms, has had an immense influence in the but on the opposite side. Other trees are modified formation of the solid crust of our satellite. We even in their foliage; they have only half a head, can perfectly account for all the facts now enumerthe other has disappeared under the action of ated, by supposing a number of whirlpools in the the wind. Orange and citron trees become superb fluid matter, whose amplitude diminished with the in the woods. In the plain, and where they are fluidity of that matter. Nothing is to be seen on without shelter, they always continue weak and the surface of the moon which reminds us of our crooked.

chains of mountains with their lateral branches, or of our great valleys with their numerous rami

fications, &c. We see, indeed, many well marked From the Edinburgh Philosophical Journal. fissures, as, for example, at the bottom of the mare

raporum; but these fissures are simple ; several On the Surface of the Moon. By Captain Rozet.

diverge from one centre, as in Tycho, Copernicus, M. ELIE DE BEAUMONT has already been enabled, Kepler, &c., and form radiating cracks, analogous by means of the beautiful selenographic delinea- to those in Von Buch's craters of soulevement, but lions of Lohrmann, and of Beer and Mädler, to much more considerable. One of the fissures of make some very remarkable comparisons between Tycho traverses the moon diametrically. A conthe forms presented by certain portions of the Linued study of the various portions of the moon, mountainous masses of the earth, and the annular

under all inclinations of the solar rays, enables us openings of the surface of our satellite.

to recognize two layers which are quite distinet, During the summer of 1814, one of my friends but two layers only ;-the bottom of the great having directed my attention to the circular forms greyish spaces, which is also that of the rings : of nearly the whole of the variations of the lunar and a scoriaceous crust, elevated above that botton surface, I have devoted myself since that time to to a height which has been measured at a great the study of the phenomena presented by these number of points. These measurements have variations of surface, having, at the same time, afforded me the means of calculating the thickness called in the aid of the beautiful German maps, of this crust, and I found that the mean is 642 and of various works already published on ihe metres (2106 English feet.) sabject.

From all the facts I have ascertained, and from The contours of all the great greyish spaces all the deductions to which these facts have led which, for a very long time, have been termed me, I think I may draw the following concluSwas, although it is known with certainty that they / sions : cannot be inasses of water, are formed by arcs of 1. The lunar globe has originally been in a circles which intersect one another. The number state of fusion, and has been gradually cooled. of arcs sometimes amounts to two, rarely to one 2. During the formation of the extemal scoriamare crisium. These contours present circular ceous pellicle, there existed in the mass whirlpools escarpments which seem perpendicular, but the lor circular movements, which, driving the scorir inclination of many of which is 45 degrees. The from the centre to the circumference, formed annematter composing them appears to be swelled up, lar ridges, by the accumulation of those scoria at and their height often exceeds 4000 metres (up- the limit of the undulation. When several whirlwards of 13,000 English feet.) In the interior of pools occurred in such circumstances, that the die the seas we remark annular openings or perfect tance of the centres, taken two and two, was less rings, whose diameter amounts to 10 myriametres than the sum of the radii, there resulted an enclosed (upwards of 60 English miles,) and the height of space, bounded by arcs of circles. When the whose terminal ridge is 4000 metres. Several of distance of two centres was greater than the sum them have a peak in the centre, which is a little of the radii, two complete rings were formed. less elevated than the edges of the ring.

3. The amplitude of the whirlpools diminished The large grey spots cover a great portion of with the fluidity of the surface, but the phenome. the northern, eastern, and western regions of the non continged throughout the whole duration of disc, and leave in its southern part a brilliant the process of consolidation. space, covered with an infinity of rings of all di- 4. The mode of formation which we assign to mensions. These rings are simple and isolated, the lunar rings, altogether excludes the idea of complex, or united together, two and two, three craters resembling those of our volcanoes. and three, &c. When they touch one another. 1 5. The surface of our satellite being thus conthe contours are always rendered imperfect: and solidated, no solid or liquid layer coming from the it is generally the smaller one which encroaches exterior was subsequently deposited upon it ; for, on the larger. In the interior of the large rings otherwise, the small rings and the fissures would there are almost always present sinaller ones, have disappeared. The perfect preservation of all which cut the edges when they touch them. The these variations in external configuration, shows bottom of the rings seems to be flat, but that bot- that no liquid has ever existed in considerable

quantity, either at the surface, or even in tho • Annuaire pour l'an 1846.

atmosphere of the moon.

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