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cences of the times that are past; they flow from the golden harp whose pæans swept over the hills and the valleys of the first men; they are the chaste images of primæval poesy, clad in all the elegant simplicity of which a powerful and refined language will admit. The Songs of Ossian are a powerful illustration of these remarks. In the old ballads, and other remains of our early poetry which are preserved, we cannot fail to perceive a beauty and pathos which do not exist, or which are not so discernible at least, in the productions of the middle poets. It may be said with truth, though much difference of opinion will exist on this point, that a very great proportion of the poetry we have been taught to admire, is nothing more than cold, metaphysical rhyme.

Poetry and music are twin sisters, and the observations which have been made on the former, will apply to the latter. Olden times were more happy, because less artful, in their musical compositions than we are. When the venerable minstrel sat at the foot of Plinlimmon or of Snowdon, and "the wild harp rung to his adventurous hand," he awoke those simple, yet powerful strains, which found answering chords in every human heart; that could animate the hearer, and impel him forward to lofty deeds, or soothe the most perturbed bosom, and "to infant weakness sink the warrior's arm."

The degenerate style and disgusting intricacies of Italian composition, have almost superseded all that is harmonious-all that is beautiful-all that is decent in music. The true British taste is best evinced by that feeling of devotion with which it listens to the compositions of Handel, and by the thrill of ecstacy and animation with which it welcomes the chorus of Von Weber.

Painting is that delightful art which embodies on the canvass the exquisite ideas and the lofty imaginings of poësy. Its principles are unalterable, yet it is an art susceptible of constant improvement, since the working materials are being brought continually nearer to perfection. Every truly refined nation will have its peculiar school of painting, which will display the national character and the genius of the people. The British school excels in portrait-painting; in delineating men as they are; not clothed in the adventitious pomp of historical display, but revealed in their every-day character to the eye of the world.

Let us now devote a few minutes' attention to the causes which induce the rise and decline of monarchies.

A monarchy is originally a family of men

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whose wants lead them to union; and to render that union permanent and effective, they submit to be guided by laws and directed by a leader, whose authority at once preserves order in the infant state, and invigorates its proceedings.

Nothing in this world is at any time exempt from change. In some cases, the action of one thing upon another causes the second to increase, and when this is submitted to the action of a third power, it is reduced to its former state, or, to take the word in a limited sense, annihilated: thus one grain of sand associates with others, till it becomes a ponderous mass of stone; and this is again reduced to sand, by the action of water falling in continual drops. This is strongly illustrative of the rise and fall of monarchies: a succession of favourable events lifts them up, and a series of unfortunate circumstances throws them down again. There is undoubtedly a certain point to which a nation may ascend, and when that is attained, no human counsels can effectually oppose its gradual or rapid decline.

The primitive simplicity of a people is the foundation of their future power and greatness. Their flocks and herds are numerous, and population rapidly increases; for the numeral power of society will always grow proportionately with the means of subsistence. Being compelled to take up arms, in defence of themselves, their families, and their pastoral property, from merely acting on the defensive, they come, at last, to act hostilely against other associated bands; and their numbers procure them a victory, which their hardihood and simple manners are well calculated to improve. They go on adding one tract of territory to another, introducing useful arts, acquiring some little additional knowledge by every conquest, and gradually emerging from barbarism. At length we see them in possession of an extensive country, living in well-built and strongly defended cities, and contemplate the mighty mass engaged in commerce and agriculture. At this era of a nation's greatness, it is of the first consequence, that its rulers do not sink themselves in sensuality, but employ all their energies in its management and defence; they are not to introduce, by their own example, a love of luxury and indolence, but to stand forth as the fathers of their country, and watch over its best interests with paternal solicitude and a jealous eye.

When a nation relies wholly on its commercial interests and its present importance in the scale of empires, and neglects its internal resources, of which agriculture may

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rates from the watery part in the same manner, though not so perfectly, as it does by free exposure to the air. The proportion of caoutchouc contained in the juice by the oldest stems, is nearly equal to two. thirds of its weight; the juice from the younger trees is much more fluid, and contains a considerably smaller proportion of this substance.

According to the experiments of Mr. Howison, cloth of all kinds may be made impenetrable to water by impregnating it with the fresh juice of the urceola; and the pieces thus prepared are most effectually and expeditiously joined together by moistening the edges with the entire juice, or even the more watery part, and then bringing them in contact with each other. Boots, gloves, &c. made of this impervious cloth are preferable even to those formed of pure caoutchouc, as they are more durable, and retain their shape better. If a sufficient quantity of this juice could be obtained, it might no doubt be applied to a vast variety of important purposes.

The colour of fresh caoutchouc is yellowish white, but by exposure to the air it becomes of a smoke grey. American caoutchouc, in the state in which it is brought to Europe, being formed of a multitude of extremely thin layers, each of which is exposed to the air for some time in order to dry before the next is laid on, is of a yellowish smoke-grey colour throughout, but masses of East Indian caoutchouc being formed more expeditiously, are darkcoloured only on the outside; when cut into, they are of a very light brown, which however soon deepens by the action of the air. Caoutchouc is perfectly tasteless, and has little or no smell, except when it is warmed; it then gives out a faint peculiar odour. The elasticity of this substance is very remarkable, and indeed is one of its most characteristic properties. Slips of caoutchouc when softened by immersion for a few minutes in boiling water, may be drawn out to seven or eight times their original length, and will afterwards resume very nearly their former dimensions. During its extension, a very sensible warmth is produced, as may be perceived if the piece is held between the lips; and on the contrary, when it is allowed to contract, a decrease of temperature will immediately take place. By successive extensions and contractions, especially in cold water, its elasticity is much impaired; but if in this state it is immersed for a time in hot water, it re-absorbs the caloric which it had lost, returns to its original size, and recovers its primitive elasticity.

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At the temperature of about 40° Fah. caoutchouc begins to grow rigid, its colour becomes much lighter, and it is nearly opaque, and, as the cold increases, it becomes still more stiff and hard. These changes, however, depend merely on temperature, for a piece of hard-frozen caoutchouc again resumes its elasticity on being warmed. The fresh-cut surfaces of this substance will unite together by simple contact, and, by a proper degree of pressure, may be brought so completely in union as to be no more liable to separate in this part than in any other. Its sp. gr. according to Brisson, is 0.933. It under goes no alteration by the action of the air at the common temperature. When boiled for a long time in water, it communicates to this fluid a peculiar smell and flavour, and is so far softened by it, that two pieces thus treated, and afterwards strongly pressed, will form a permanent adhesion to each other.

When heated to a temperature nearly equal to that of melting lead, caoutchouc runs into a black viscid fluid of the consistence of tar, which does not concrete on cooling, neither does it dry by long exposure to the air. When held to a candle it readily takes fire, and burns with a copious white flame, and a large quantity of dark-coloured smoke, exhaling at the same time a peculiar, but not unpleasant odour: from its smoke a considerable quantity of very fine lamp-back may be collected. In dry distillation it gives out ammonia and carbonated hydrogen.

Concentrated sulphuric acid, when heated, acts with great energy on caoutchouc, reducing it to a black friable carbonaceous substance, the acid at the same time being in part decomposed, and sulphureous acid being produced. When treated with nitric acid, azotic gas and car bonic and prussic acid are disengaged, oxalic acid is left in solution, and the resi due is converted into a yellow friable mass. By digestion in oxymuriatic acid the colour of caoutchouc is discharged, it becomes opaque, indurated, and wrinkled, like tanned leather, but appears to undergo no other change. Similar effects are produced, though more slowly, by muriatic acid.

Ammoniacal gas, according to Dr. Thomson, is absorbed by caoutchouc, and converts it into a soft, glutinous, and inelastic substance. The same able chemist also states, that the caustic fixed alkalies are capable of combining with, and dissolving it. Cacutchouc is also soluble with ease at a boiling heat in the expressed

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Rectified oil of turpentine, at the common temperature, acts without difficulty on caoutchouc, first rendering it transparent, and enlarging its bulk considerably, and in the course of a few days, effecting a complete solution. This compound is of the consistence of drying oil, and when spread thin on wood, it forms a varnish which however is a long time in becoming quite dry. When mixed with a solution of wax in boiled linseed oil, it composes an elastic varnish which is used for covering balloons.

The only menstrua for this substance, from which it can be separated again unaltered, are ether, naphtha, and cajeput oil.

The solubility of caoutchouc in ether was first discovered by Macquer, a circumstance which, from its frequent failure in the hands of other chemists, was very generally called in question, till Cavallo cleared up the difficulty by showing the necessity of employing washed ether for this purpose. If rectified sulphuric ether is shaken in a vial with some pure water, it dissolves about a tenth of its weight of this latter substance, and in this state is capable of effecting a complete and speedy solution of caoutchouc. The solution is of a light brown colour, and when saturated, is considerably viscid. A drop of it let fall into a cup of water immediately extends itself over the whole surface; and the ether being partly absorbed by the water, and partly evaporated, the water is found covered with an extremely thin film of caoutchouc, possessing its elasticity, and all its other characteristic properties. A similar effect takes place when cloth of any kind is soaked in the solution, or any hard substance is smeared over with it; on exposure to the air, the ether is rapidly evaporated, and the caoutchouc, with which it was combined, is left behind. The affinity of this solution for caoutchouc is very great; if the edges of two pieces of caoutchouc are dipped in it, and immediately brought in close contact with each other, as soon as the ether is evaporated, they will be found to be perfectly united.

There are two circumstances which must always prevent the extensive use of the etherous solution of caoutchouc, admirably qualified as it is in other respects for many useful purposes; these are, first, its expensiveness, and, secondly, the extraordinary rapidity with which the ether evaporates; thus rendering it impossible to lay

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which it is applied. In order to form tubes or catheters of this substance, the best method is to cut a bottle of caoutchouc in a long single slip, and soak it for half an hour or an hour in ether; by this means it will become soft and tenacious, and, if wound dexterously on a greased mould, bringing the edges in contact with each other at every turn, and giving the whole a moderate and equal pressure by binding it with a tape, wound in the same direction as the caoutchouc, a very effectual union will be produced ; after a day or two, the tape may be taken off, and the cylinder of caoutchouc may be rendered still more perfect by pouring a little of the etherous solution into a glass tube closed at one end, the diameter of which is a little larger than that of the cylinder of caoutchouc; which being introduced into the tube, will force the solution to the top of the vessel. Let the whole of the apparatus be then placed in boiling water; the ether will be evaporated, and a smooth and uniform coating of newly deposited caoutchouc will remain upon the cylinder.

Petroleum, when rectified by gentle distillation, affords a colourless liquid not to be distinguished from the purest naphtha, and this, according to Fabbroni, has the property of dissolving one-seventieth of its weight of caoutchouc, and of depositing it again unaltered by spontaneous evaporation. It does not appear, however, that this menstruum has been much employed. ·

The solubility of caoutchouc in cajeput oil was first noticed by Dr. Roxburgh. This is an essential oil procured in India, by distillation, from the leaves of the Melaleuca Leucadendron. The solution is very thick and glutinous; and is decomposable by alcohol, this latter uniting with the essential oil, and leaving the caoutchouc floating on the liquor in a soft semifluid state. This, on being washed with alcohol, and exposed to the air, becomes as firm and elastic as before it was dissolved; while in the intermediate state between fluid and firm, it may be drawn out into long transparent threads, resembling, in the polish of their surface, the fibres of the tendons of animals, and so extremely elastic, that when broken, each end immediately returns to its respective mass. Through all these stages the least pressure with the finger and thumb is capable of uniting different portions as completely as if they had never been separated, and that without any clamminess, or sticking to the fingers.

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