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THE CATHEDRAL OF SENLIS.

themselves, confess and lament this paucity of infor. Among the many religious edifices that boast the mation ; and M. de Jolimont, one of the highest name of Cathedrals, there are few less generally known modern authorities on the subject, and the one who than that which distinguishes the little town of Senlis, has been our chief guide in these notices of the French in France. In all probability, one half of our readers Churches, candidly tells us, that in spite of his most never heard of its existence, and will derive their first active researches, his account of this structure savours knowledge of the fact from the pages of this Maga- overmuch of this “complete sterility of documents." zine. It certainly is not a structure remarkable for The institution of the Church of Senlis, is referred the beauty of its outward form, or the attractions of to the third century, and is ascribed to a certain its internal architecture; nor is its name linked with “Saint-Rieul," who visited Gaul with the renowned any of those pleasing associations which impart so St. Denis, the well-known patron-saint of France, much interest to buildings richer in historic fame. in order to effect the conversion of the pagan inhaNevertheless, as our object is to furnish a complete bitants. His mission was attended with success; the illustration of the ecclesiastical architecture of foreign Sylvanectes became Christians, and he became their countries, as well as of our own, it is quite impos- bishop. We are to suppose, that under the auspices sible to overlook this modest cathedral, however of this prelate, the first cathedral was erected; but, humble and unpretending its merits ; nay, were it after wading through the usual mass of miraculous even deformed with positive ugliness, still the com- legends, we lose every clue to its real history. After prehensive nature of our design would forbid us to being kept, for a long lapse of ages, in utter darkness pass it over in silence.

as to every thing concerning it, we at last find our. Senlis is but a little town, standing to the north-selves on more solid ground, and learn, that at the east of Paris, at a distance of about thirty miles. beginning of the fourteenth century, there existed a According to the ancient division of the French terri- cathedral, which soon afterwards met that too comtory, it formed a part of what was called the Isle of mon fate of the early ecclesiastical buildings, destrueFrance; it is now comprehended within the depart-tion by lightning. On its ruins was raised the ment of the Oise. It is a very ancient place, having present edifice, though by very slow degrees ; indeed, existed in the time of the Gauls; and it still bears its appearance indicates the lingering nature of its about it the marks of its antiquity, in the remnants construction, for it exhibits a mixture of the various which may yet be traced, of its old fortifications. styles which prevailed through several centuries. The Romans first called it Augustomagus ; but it Our readers will see, by a glance at the engraving afterwards obtained the name of Silvanectum, pro-contained in the preceding page, that the exterior bably, as has been suggested, on account of the of this cathedral has very little that is splendid or forests which then surrounded it, and which have highly-finished in its appearance. The character of not wholly disappeared at the present day. In the its architecture is severe; but there is something modern history of France, it is not entirely destitute pleasing in its simplicity, and in the contrast which of interest. During the contest between Henry the it offers to its more gorgeous brethren. Some of the Fourth and the celebrated League, it sided with the French writers are much disposed to find fault with monarch, and furnished him with supplies for the it; they see little in it to admire, and speak of its prosecution of the siege of Paris.

style as being in the worst taste. The traveller The modern town, if that can be called modern whom we noticed before, as being displeased with which has nothing but what is antiquated about it, the town of Senlis, seems fairly in a passion with its presents very few attractions. It is badly built, and cathedral; he calls it a mean building, and one of most of its streets are both narrow and crooked. A the ugliest gothics that he ever met with. The French author, who wrote towards the close of the tower, he says, is lofty, but wanting in delicacy; last century, speaks of it in very unprepossessing --the portals are in the very worst taste ;-and language;

he never saw any place so near a the nave is so short as to form scarcely a third of great capital more dull, sad, and silent. Its cha- | the church ;-in short, it is labour and stone thrown racter is somewhat altered at the present day, though away. Others of his nation view things with a not to such an extent as to give it a very lively ap- different eye. M. de Jolimont is one of them; and pearance; but the inhabitants are animated by the he says that if the Cathedral of Senlis be of less same spirit of industry which so strongly marks some general importance,—if it be less sumptuous in its other towns in this portion of France, and carry on appearance, and built in a style less uniform and several manufactures to a considerable extent. The regular than other buildings of its kind,-still it water in the river which flows close by, is supposed presents much richness in detail, and many by them to possess a peculiar quality, that ren:lers things highly curious and interesting in its different it better adapted than any other for the washing of parts. wool; "the fact may be doubtful,” says Malte-Brun, The principal front is represented in our view. “ but it must be admitted that many persons are It is rather narrow, but perfectly regular in every employed in that branch of industry." There are thing excepting the towers; these were necessarily also several establishments for bleaching, which is dissimilar, for Senlis was a suffragan bishopric, and practised on a large scale ; formerly, indeed, Senlis was not entitled to that “uniformity of towers," had such a reputation for its excellence in this art, which was confined to the cathedrals of metropolitan that goods used to be sent thither for bleaching, sees, to abbey churches, and to those attached to from all parts of France. It has likewise, cotton- colleges of royal foundation. The portals are, as manufactories, besides establishments for the prose- usual, three in number, and decorated with th: cution of other branches of industry; and the stone customary profusion of statues and bas-reliefs; which is found in the neighbouring quarries, furnishes there are three little rose windows, but, contrary the material for a considerable trade. The number to the usual practice, these are placed at what is of inhabitants is between four and five thousand. called the last stage of the edifice. But the chief

The Cathedral, of course, forms a very prominent feature of the building is the southern of the two object in this little town. Of its origin and early towers—which is remarkable for it loftiness, and the history we have little to say, for scarcely any thing elegant lightness of its architecture. It is about 220 is known concerning them, The French writers | feet high, and as it surpasses in elevation all the

he says,

" that for

neighbouring hills, it is visible from a great distance.

THE SCILLY ISLANDS. Like the rest of this front, it is faulty from its nar

About nine leagues west by. south from the Land's rowness; which, besides being a drawback on its | End, Cornwall, from which they are clearly visible, beauty, seriously obstructs its utility; the bells have lie the Scilly Islands. This wild and romantic cluster not room to swing, and on more than one occasion of rocks, many of which, on a distant view, appear have been broken by coming in contact with the wall. like old castles and churches rising out of the sea,

The interior of this Cathedral is of the same cha- | although scarcely known, except, perhaps, by name, racter with its outward form-simple and severe to most persons in this country, possesses very conexhibiting an absence of ornaments, almost even to siderable claims on our attention. nakedness. It is somewhat remarkable for the size

These Islands were known to the ancients. By and number of those side-chapels which are common the Greeks they were called Hesperides and Cassiterides, in the French cathedrals, but rather a rarity in those or the Tin Islands, probably from their contiguity to of our own country. The choir is somewhat dis- Cornwall (where the Phænicians traded), for not a figured by bad pictures, which are little in harmony vestige of any ancient mine can now be discovered with the general style of the building.

upon them.

It is evident, however, that they have undergone

great changes since the period referred to, as Strabo There is one tribe of caterpillar called Surveyors, or

speaks of the islands as not exceeding ten in number, Geometers, which walk by first fixing the fore-feet, and whilst now there are upwards of one hundred and then doubling the body into a vertical arch; this action forty, only six of which, however, (for the greater brings up the hind part of the caterpillar, which is furnished portion are mere rocks,) are inhabited. These are,— with prolegs, close to the head. The hind extremity, being St. Mary's, which contains twelve hundred inhabitants; then fixed by means of the prolegs situated at that part, St. Agnes, three hundred; St. Martin's, six hundred; the body is again extended into a straight line; and this Trescow, three hundred and fifty; Bryer *, two hunprocess being repeated, the caterpillar advances by a succession of paces, as if it were measuring the distance, dred; and Sampson, one hundred and fifty t; making by converting its body into a pair of compasses. At the an aggregate of about two thousand eight hundred same time that they employ this process, they further inhabitants, which are rapidly increasing, the births provide for their security, by spinning a thread, which they greatly exceeding the burials; indeed, so healthy is fasten to different points of the ground, as they go along.

the climate, and so robust are the people, that it is a Many other species of caterpillar practise the same art of spinning fine silken threads, which especially assist them

common saying amongst the Scillonians, in their progression over smooth surfaces, and also in one man who dies a natural death, nine are drowned." descending from a height through the air. The caterpillar of Cases of deformity are unknown. the cabbage-butterfly, is thus enabled to climb up and St. Mary's is the largest of the Scilly Islands, down a pane of glass, for which purpose it fixes the threads being about nine miles and a half in circumference, that it spins in a zigzag line, forming so many steps of a rope-ladder. The material of which these threads are population as the rest of the group.

and containing, as we have seen, nearly as large a

It possesses an made, is a glutinous secretion, which, on being deposited on glass, adheres firmly to it, and very soon acquires excellent harbour and pier; and carries on some consistence and hardness by the action of the air.

trade, vessels to the value of £20,000 belonging to Other caterpillars, which feed on trees, and have often it; indeed, twelve fine schooners were at one period occasion to descend from one branch to another, send out a launched in the space of six months. The hills are rope made with the same material, which they can prolong rocky, rising in some places to a great height, and indefinitely; and thus either suspend themselves at

are enriclied with mineral ores. The valleys are pleasure in the air, or let themselves down to the ground. They continue, while walking, to spin a thread as they generally fertile; although there is some marshy advance, so that they can always easily retrace their steps ground: the island contains three towns, has a by gathering up the clue they have left, and reascend to custom-house, a garrison, and druidical remains the height from which they had allowed themselves to abound in several places.

abound in several places. It seems not improbable, drop.

0. N.

that St. Mary's will, at no great distance of time, be [DR. ROGET's Bridgewater Treatise.]

divided by the sea.

St. AGNES, which forms the subject of the acThe GLOBE Volvox.—This extraordinary animalcule is companying engraving, being the most elevated of of a globular form, and usually of a light-green colour, the Islands, and lying directly exposed to the Atlantic sometimes of an orange-brown. The envelope is composed Ocean, has been chosen for the erection of a very of a diaphanous membrane, beneath the surface of which; high and strong granite light-house, which stands are disposed at equal distances, small spherical bodies of a green colour. The proximity of these tubercles is greater, nearly in the centre, in the latitude forty degrees, the younger the specimen; and as these tubercles contain fifty-three minutes, thirty seconds, north. This the colouring matter of the animalcule, the young always structure, which was built in 1680, has been rendered appear more coloured than the old ones, as the transparent admirably adapted for the purpose for which it is spaces between the pustules are augmented in the latter, designed. The machinery is now so contrived, that and spread over a greater surface. Within the parent are often seen a number of from six to forty smaller

its light progressively sweeps the whole horizon at and

ones, even within these, when about to be excluded, another intervals of three minutes'; and by its regular intergeneration may be observed. The young within the parent, mission and increase, is readily distinguished from and this forms the most striking character of this species, every other on the western coast. There is also an may be observed at first attached to the inside of the mem- | obelisk on the island of Trescow, which is almost branous covering, but long before their birth revolving as valuable a sea-mark in the day-time, as the lightfreely in the parent, and others again with them. At length house is at night. the parent globe bursts, and the young are slowly evolved; when this is completed, the parent, like the fabular phenix,

The inhabitants of St. Agnes, and the most western dies, and its body separates into numberless parts. This of the islands, derive their chief source of support in animalcule moves in all directions, forwards, backwards, winter from piloting ships; whilst in summer they up and down, rolling over and over like a bowl, spinning cruise about the channel for the purpose of disposing horizontally like a top, or gliding along smoothly without turning itself. Its diameter, when full grown, is about safe harbour, called New Grimsby, much frequented by coasting

Between Trescow and Bryer, there is a very commodious and one-thirtieth of an inch, and is, therefore, easily perceived vessels in the winter. by unassisted vision. It is found most abundant during † Scilly, which gives its name to the group, is, singularly enough, spring and summer, in ponds and stagnant water.- one of the smallest, not exceeding an acre in extent. PRITCHARD

1592

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LIGHT-HOUSE ON ST. AGNES, ONE OF THE BCILLY ISLANDS. of fish, eggs, vegetables, &c., to homeward-bound was accordingly provided in the island of Trescow, vessels. There are five boats at St. Agnes, employed for the purpose of storing and curing fish; boats in this way, each sloop-rigged, of a burden of adapted for the mackerel and pilchard fisheries were twenty-two tons, and navigated by seven or eight purchased, and others were repaired; nets and men, who are joint-proprietors in the venture, and various kinds of tackling were at the same time respectively share the produce of their industry on liberally supplied." shore. They sometimes run on these excursions The Society for Promoting Christian Knowledge thirty leagues to the westward, and in case of the has for many years had a Mission established in homeward-bound being detained by contrary winds, these islands ; but it has long been felt that the make their terms accordingly—the market being Religious instruction of these islands, which as a here regulated by the winds alone.

part of the Duchy of Cornwall, yield a revenue to One important good, however, results from the the Crown, ought not to be left dependent upon the summer-cruises of the Scillonians, for they are thus bounty of any Society whatever. Memorials have enabled to give information of their situation to those therefore been presented, on several occasions, to His vessels which have been driven out of their reckoning Majesty's Government, earnestly requesting that from stress of weather and other causes: this in- some public provision may be made for the spiritual formation, we are told, has saved many hundred wants of the islanders; and it was hoped that, as ships, and almost numberless lives, which would the obstacles which formerly existed were removed otherwise have been lost on the rocks of Scilly. On on the expiration of the lease, the prayer of the this ground alone, the Scillonians have a strong memorial would have been complied with ; but the claim on the generosity, not only of the British mer- islands still remain in the same state. In the winterchant and ship-owner, but on the Government itself. season, it frequently happens, that the Rev. George And this leads us to advert to an interesting passage Woodley, one of the two missionaries sent by the in the history of these wild and cheerless rocks. Society, and resident minister at St. Mary's, is pre

“In 1819, from a combination of unfortunate vented from passing over to the islands alluded circumstances," remarks Dr. Paris, in his admirable to, in consequence of the boisterous state of the work on the Land's End district *, “the inhabitants weather for many weeks together, during which were reduced to such extreme distress, that it became period the people are left wholly destitute of spiritual necessary to appeal to the generosity of the public instruction. At such periods, in St. Agnes, the in their behalf; and notwithstanding the difficulties church-service is read by the infirm and aged schoolof the times, the sum of 90001. was collected for master, who is described as being nearly deaf and their relief. In this great work of charity, it is but blind. Our correspondent feelingly alludes to the an act of justice to state, that the Society for Pro- state of the poor people, who are thus deprived of moting Christian Knowledge, by their purse, as well “ the one thing needful ;" and we trust that the as by their writings, performed a very essential ser- present allusion to the circumstance may awaken the vice. The funds thus obtained, were in part appro- desired spirit. priated to the relief of the immediate and pressing A wide field then still remains for philanthropic and distress under which they laboured, whilst the re- Christian exertion, by providing requisite means for mainder was very judiciously applied towards the the spiritual instruction of the members of the Church, promotion of such permanent advantages, as might and by enabling the Scillonians to avail themselves of prevent the chance of its recurrence. A fish-cellar the advantages of their locality, as for want of proper To which, and to the communications of a correspondent, we

boats they are unable to extend their fisheries. There have to confess our obligations in the present paper.

are four Wesleyan chapels in the islands.

The land is divided in small portions, upon the white: this might, Dr. Paris conceives, be advanprinciple that as great a number of persons as pos-tageously employed in the manufacture of Porcelain. sible may be benefited. Some do not possess more The property of the islands is at present vested in than a single acre; others have two or three acres ; the Duchy of Cornwall, to which it reverted in 1831, but none cultivate more than four. The lands are after having been for about two centuries and a half all held of the Lord Proprietor for a term of twenty- | under the sway of the Godolphins and Osbornes, one years. The soil is good, and produces excellent Dukes of Leeds. potatoes, and grain of all sorts, except wheat, which, The civil government of the islands is chiefly although anciently grown in large quantities, has not managed by twelve of the principal inhabitants, who for many years been found to thrive ; barley bread, constitute what is termed a Court of Twelve, in therefore, is in general use.

which a military officer presides. This court is held Two uninhabited islands, called Gew and Annet, monthly at Church Town, St. Mary's; it has juris. situated about three-quarters of a mile from the diction in civil suits and minor causes; but persons north-western extremity of St. Agnes, besides sup to be prosecuted for felonies, and other criminal plying the other islands with fern and turf for fuel, offences, must be sent for trial to the Cornwall Assizes are extensively used for grazing sheep, almost every at Launceston; the sheriff of that county, however, family possessing some. These animals are chiefly has, singularly enough, no jurisdiction in the islands. kept for their wool, with which the women make the “ The intensity of the attachment of the Scillonian clothing for themselves and families. The sheep to his native rock,” remarks the ingenious writer we are very small, and in bad condition, having little have already quoted,

have already quoted, “ forms a striking contrast with else than the Algæ, locally called hare-weed, to sub- the feelings of the roving inhabitant of an alluvial sist upon ;

the latter constitutes the only manure country, where every object, it might be presumed, used. The effects of this weed in fertilizing the land was calculated to excite and sustain the strongest are surprising, for, although fallows are unknown, it attachment; but the principle is wise and universal ; rarely fails to produce abundant crops. Large quan- the plant is easily loosened from a generous soil, but tities of this weed are burned into kelp during the with what difficulty is the lichen torn from its rock!" summer; in winter it forms almost the entire sustenance of horses, cows, and other live-stock; for, as no land is left in grass, the cattle may be said to FAMILIAR ILLUSTRATIONS OF EXPERIbe thrown upon their own resources.

Rabbits, wild

MENTAL SCIENCE. fowl, and sea-birds, abound upon the islands, and

No. VI. HEAT. EXPANSION. a great quantity and variety of fish are taken off their shore; a portion of which are salted for winter One of the most obvious effects produced by the consumption, when they form, indeed, the chief food entrance of heat into certain bodies, is an increase of of the people.

their bulk. This is termed expansion. The rate of We have thus seen, that the Scillonians combine expansibility in solid and liquid bodies is very by turns, the three occupations of farmers, fishermen, irregular ; each substance possessing this property in and pilots; the latter pursuit is, however, the most

a degree peculiar to itself, but dependent on certain lucrative. In the stormy weather, which so frequently conditions in its structure and general character. prevails on our western coast, and especially off the Aëriform bodies expand uniformly; that is, whatalmost desolate and dangerous rocks of Scilly, they

ever may be the character or quality of the gas, or have frequently been honourably distinguished for vapour, submitted to the action of heat, if all other their exertions in the preservation of the many

circumstances are favourable, equal quantities of heat vessels that have been wrecked on their shores will produce equal degrees of expansion. during the winter.

The change of dimensions in solid bodies, under The commotion of the elements, during a storm in the influence of heat, is comparatively small. In the Scilly Isles, is certainly most awful. Carrington, liquids it is sufficiently apparent to be detected one of the least known, though among the best of without the aid of instruments. Aëriform bodies modern poets, thus beautifully alludes to the ap- expand in a greater degree than either of the former. pearance of the rocky isles on our western coast, in Their enlargement is, therefore, still more distinctly storm or calm :

ascertained from observation only. Other sounds

Of solid bodies, we have already mentioned metals, Save those of shrieking winds, and battling cliffs,

as being the best conductors of heat; they also Are seldom heard in those deserted isles !

expand the most readily. The following table The spirit of desolation seems to dwell

exhibits the order in which the most commonly Within them, and although the sun is high,

known metals, in their solid state, expand. The And nature is at holy peace, they have An aspect wild and dreary.

figures denote the average rate of expansion possessed But in the wint'ry storm, when all that sea

by each metal in passing from the temperature at The terrible Atlantic, breasts their rocks

which water freezes (32°) to that at which it þoils In thund'ring conflict, the unearthly howl

(212°.) Might almost wake the dead. It has been computed that not more than six days from 32° to 2120 of perfect calm occur in these islands, in the course Lead of a year; and that the wind blows from between Tin (Cornish) S. W. and N. W., for more than half that period. Silver The climate is exceedingly mild and equable; and Brass . exception, the whole of the islands consist of granite, Gold (standard) )

Zinc expands, on being heated.} słyth of its volume.

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zizth which, however, varies in its formation, and is of the Ditto (pure) most valuable description. Several beds of Porphyry Iron · are to be found at St. Mary's; and at the Lizard Ditto (cast)

• Jóoth Point, in the island of Trescow, a variety of granite Steel

Jogth occurs, in which the felspar is of a remarkably pure Platinum

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Hence it appears that a mass of zinc equal to 113 that by neglect, or accident, the whole of the water cubic inches, at the temperature of melting ice, will has been drawn off or evaporated from an iron boiler, become, on being heated to the temperature of it should be permitted to cool previously to its being boiling water, equal to 114 cubic inches. On com- re-filled ; a simple expedient, that will effectually paring this result with what would occur, under prevent its being broken and rendered useless. similar circumstances, with platinum, we perceive It has been supposed that there exist a few that the expansibility of zinc is nearly three times exceptions to the general law of the expansion of greater than that of the last-mentioned metal. It solid bodies by heat. On a closer examination, these would require 336 cubic inches of platinum, to produce exceptions will be found to be so only in appearance, an expansion of volume equal to one inch. To ascer not in reality. Among the apparent departures from tain the linear expansion, that is, in the direction of what seems an immutable principle, we may mention its length, of the respective metals, we have only to clay; certain kinds of which, when used by themmultiply by 3, the figures below each line of the selves, or when mixed with sand, as in the manu. fraction, termed the denominator. Thus: we find facture of bricks and tiles, contract, on the application by the table, that cast iron expands güoth (one three of heat, up to a very high temperature. This hundredth) of its volume between the temperatures contraction, however, is evidently due to the separa320 and 212o. If we multiply 300 by 3 we have 900. tion of considerable quantities of moisture, which It follows, therefore, that a bar of cast iron whose was previously combined with the clay, and also to length at 32°, is 900 inches, will, at 212°, be equal to an entire change produced by heat in its general 901 inches.

character. As a familiar example, we may refer to A knowledge of the rate of expansibility possessed the porcelain ware in common use; every article of by different substances, is highly important to which is made larger than it is designed to be after architects, surveyors, and general artificers. In it has been submitted to the action of the fire. adapting iron beams, or roofs, or gutters, to extensive Stone bottles, which are intended to contain buildings, if the effects produced upon the metal by certain quantities of liquids, are frequently found too changes of temperature were disregarded, the walls, small, notwithstanding the usual allowance had been and other parts of the buildings, would be subject to made for their estimated rate of contraction in the frequent disturbance, if they were not entirely kiln. Wood, and other vegetable substances, which thrown down. In the construction of iron bridges, have their bulk diminished by the application and in laying down mains for conveying water or of heat, must also be regarded only as apparent gas, it is also necessary to make suitable provisions exceptions to the ordinary laws of expansibility. for the difference of dimensions, incident to variations Vegetables contain not only a great quantity of of temperature. Clocks, and watches, and astro-moisture, but there reside within them certain nomical and mathematical instruments, are all liable volatile resins and oils, which are easily dissipated by to occasional inaccuracies, from the cause already heat. Hence ensue changes in their character, as noticed, and hence some exceedingly beautiful con well as changes in their form and size. trivances are resorted to as a means of compensating It is deserving of remark that, in the instances to and preventing what would otherwise occasion very which we have just alluded, of contraction by heat, serious errors.

the respective substances so acted upon do not To the expansion of bodies when suddenly heated, resume their original dimensions on being restored to and to their contraction when heat is suddenly their ordinary temperature. On the contrary, we withdrawn from them, we may attribute many of the find them, for the most part, becoming subject to the phenomena which daily present themselves to our same law as other solid bodies ; additional proofs notice. Compared with some other substances, glass these, if any were required, that an important change is a bad conductor of heat. This we may easily prove, has been wrought in their elementary structure. by holding a piece of iron-wire, say two inches long, The expansibility of liquids, is greater than that of and a piece of glass, the same size and length, in the solids. By a difference of temperature equal to 180°, flame of a lamp. The metal will become too hot for alcohol (spirits of winc) expands Ath (one ninth) of our fingers long before the glass. In fact, by the aid its volume. Whale oil, in passing from 60° to 212°, of a blow-pipe, one end of the glass rod may be increases nearly th (one twelfth) of its volume. fused, whilst the other end is retained between the Water heated from 40° to 212°, expands rather fingers ; an experiment that we should be unable to more than and (one twenty-second); and mercury, perform with the metal, under similar circumstances. from 32° to 212°, 3th (one fifty-fifth) of its volume. When a small quantity of boiling water is suddenly Among liquid bodies, there is one remarkable poured into a thick glass vessel, that part of the exception in favour of water, to the otherwise general vessel immediately in contact with the water, instantly law of their expansion by the application of heat and expands, whilst the other parts retain their ordinary their contraction by its withdrawment. All other dimensions. The result of this unequal expansion, is liquids, except water, diminish in bulk as they a fracture, the heated portion of the glass being become colder, until they solidify. In a recent forcibly torn away from the other portions. A very number of our magazine*, this singular phenomenon thin glass vessel, under the same treatment, would has been fully explained. It is one of those beautiful not be broken, because heat would be more speedily illustrations of Almighty wisdom, blended with communicated to both its surfaces, which would infinite benevolence, which is eminently calculated to expand equally. A plate or a vessel of cast-iron teach us that what we are accustomed to denominate will be fractured in the same way as glass, although the laws of nature, may more appropriately be it is a good conductor of heat, if one particular part designated the laws of God. of the plate or vessel be suddenly heated, whilst the As an example of the expansibility of liquids, we other parts remain cold. Similar effects are produced need only refer to what often happens with the by the abstraction of heat, on vessels constructed of common tea-kettle, which, if quite filled with cold glass, porcelain, or cast iron. In this way it is, that water, and placed over a fire, will discharge a portion through the ignorance or carelessness of servants, of its contents at the spout or the cover, long before the cast-iron boilers now so commonly attached to it has arrived at a boiling heat. kitchen ranges, are fractured. Whenever it is found

* See Vol V. page 104.

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