The activity of the brain is now renewed by rest, and the current of our thoughts flows more freely; but still the suggestions of fancy are not corrected by the observance of surrounding objects, while the avenues to the external senses yet remain closed; and thus the train of ideas may still be incongruous.

Our morning dreams are more connected at one time than at another, which seems to depend upon the more or less perfect renewal of circulation in the organ, when some accidental cause of disturbance sets the mind at work again.

Another circumstance that may render our dreams more connected, as suggested in Dr. Wilson's Treatise on Febrile Diseases, is the employment of language to embody our thoughts; for though words be not actually uttered, yet the lips are often faintly seen to move, and the effort may be feebly made, and occupy nearly the same time as if they were; thus serving to restrain the rapid succession of ideas, and render them more connected. Without some check of this kind, in the renewed activity of the mind which now prevails, a whole history of fire, thieves, or murder, may be dreamt during the creaking of a hinge, or the opening of a door.

If the suspended influence of volition be inadequate to explain the phenomena of dreaming in general, without taking into account the physical state of the organ; still less is it capable of explaining the production of that most distressing species of dream, termed the night-mare or

INCUBUS.

This affection is so evidently connected with a peculiar state of circulation, that it seems to admit of explanation in no other way.

That the character of our dreams is much affected by external impressions, and internal feelings, is a well-known fact: thus in a windy night we may dream of being at sea, a hail-storm may suggest a dream of being in battle, or flashes of lightning make us dream that the house is on fire. In like manner, uneasy internal feelings are apt to produce unpleasant or frightful dreams, such as occur in the night-mare.

A sense of oppression is felt on the chest, which frequently suggests the idea of being held down, and the alarm thus excited sufficiently accounts for the frightful images presented to the mind, which are common to the affection in question.

The cause of the oppression on the chest is the point that remains to be ascertained; and the principles before explained lead to the inference, that undue congestion of blood in the spine, impeding the action of the intercostal muscles, and preventing the free expansion of the chest, is the most probable cause of the sense of tightness and oppression that is felt there.

The circumstances that most frequently produce the nightmare, such as indigestion, a heavy supper, and lying on the back, from their aptitude to occasion congestion in the spine, strongly confirm this conclusion: while, on the other hand, fear, which was shewn to excite the vessels to contraction, instantaneously dispels this affection, by removing the congestion, with the first struggle that is made; and thus farther corroborates the reasoning. Another species of dreaming is that called

SOMNAMBULISM.

In this state, the mind is still in a dream, intent upon some imaginary purpose, and the external senses are imperfectly restored; but the faculty of speech and the power of locomotion are freely exerted.

In such a state, persons will not only answer questions rationally, but are frequently known to unlock drawers, open doors, walk out into the air, or sit down to write letters, being inconscious all the while where they are, or that they have got out of bed, and are without their clothes. If suddenly awakened out of this state, surprise or great alarm is the consequence of the immediate renewal of perfect consciousness,

The physical cause of this singular affection appears to be an irregular distribution of blood in the sensorium, or some local congestion that impedes the uniform and simultaneous restoration of the corporeal and mental faculties.

From the principles already established, it may be inferred that the spine is not in this affection, as in incubus, the chief seat of congestion, but some part of the brain itself; for the mental faculties are evidently more obstructed than the powers of locomotion. Moreover the moral causes that are often known to occasion this affection, such as mental uneasiness, or some secret sorrow preying upon the mind, confirm this inference, from their liability to produce this state of circulation.

Grief was formerly shewn to promote congestion of blood in the brain; and its continued operation is therefore well calculated to impede the uniform and equable renewal of circulation in different parts of the sensorium.

It is true that grief is not the sole cause, and moreover that a tendency to this local congestion, when it has first arisen from accidental causes, may in time become habitual, like that which occasions epilepsy; but where frequent repetition has not rendered it constitutional, mental uneasiness is known to be its most usual cause, and strongly confirms this view of its nature.

Thus sleep, with all its attendant phenomena, seems to depend upon the periodical changes of circulation that take place in the organs of mind and voluntary motion.

These changes are not, however, confined to the organs of mind and voluntary motion, but extend to all parts. Thus every function throughout the animal economy has its periodical remission and renewal of activity; and this change in all of them is ultimately referable to the same causes, namely, their dependance upon the state of circulation, and the subjection of the circulating powers to the general laws of fibrous contraction.

ART. V. On the British Museum, and on Collectors.

It is time to inform the Public that they have lost many treasures of collections in literature and in art, or suffered by their removal from the spot most congenial to their existence for national purposes, either from some apparent indignity incurred by the possessor, or, what is still more to be regretted, from an ignorance of the nature of our great national repository, the BRITISH MUSEUM. After the irreparable losses suffered of this kind by the most enlightend men in the kingdom, who are the students or men of letters, resident in the metropolis, it becomes desirable to revise and to promulgate the constitution or laws of the Museum. Not only is the glory of the nation concerned in concentrating in its own collection the accumulated treasures of the curious, who are desirous of bequeathing them for public utility; but a higher motive exists that such rich donations should not be lost, or circumscribed in their use, as they are when in a state of dispersion, imprisoned in obscure recesses, or exiled from their natural atmosphere. The progress of human knowledge itself will be acce lerated, when the student discovers, in one sacred spot, all that human industry can afford to facilitate his researches, and to offer to his meditations; and such an institution only is worthy of a great nation. It is due time to quiet the fears, or to direct the caprice of those generous collectors, who give a wrong direction to their noble passion; whatever they bequeath to the nation should be held as a hallowed deposit, to inspire them with confidence that the undisturbed existence of collections, which they have created with so much fondness, shall be reserved in perpetuity for those congenial spirits among their successors, who will carry on an unbroken line of knowledge from age to age.

Hereafter may again arise some munificent collector, a GOUGH, a FITZWILLIAMS, a BOURGEOIS, and a HUNTER, as we have had a Bodley, and a Harley, a Sloane, and a Cracherode. Of the first four of these eminent collectors the British Museum has lost the benefit of their collections, built up, like mighty edifices, by the rare opulence and knowledge of the individuals, in such different departments in learning and art. Yet these were originally designed by the possessors to round more perfectly the circle of human acquisitions, and to have been preserved for the nation in their own repository. The motives which occasioned these rich donations to be lost to the nation in their present insulated state, were not, indeed, always honourable to their possessors, nor sometimes to ourselves. We may, perhaps, be surprised to detect men of the most enlarged spirit acting from little personal motives, even in deeds which are accompanied by the very grandeur of generosity.

GOUGH, whom we may call our English Montfaucon, for his splendid Sepulchral Monuments of Great Britain, and his Camden's Britannia, of all men best knew the national importance of the British Museum; and, of all antiquaries, none more regretted the imperfect supplies of knowledge which had hitherto entered into the national library. A perfect collection of topographical history was the costly labour of his life, and he always signified that it should never be dismembered; nor did he omit hinting, that there was but one place where the history of our country could be appropriately found, to be always at hand, the library of the nation. Among the honours which one of his fortune and taste had set his heart on, was that of becoming one of the trustees of the British Museum; this honorary title was, as he said, the blue riband of literature. But Gough was a man of irritable and sullen habits, and one ever liable, in any place, to find an enemy rather than a friend. The honour he desired he never could obtain; and, though he was so magnanimous as to persist in his resolution, of never separating his collection, he was mean enough to indulge his personal pique before the public service he had proposed in his happier hours. He either revoked his former bequest to the Museum, or gave it a new direction to the university of Oxford, where, although it is deposited in " the antiquaries' closet," that land of the Latins can seldom be congenial to the Gothic story of British antiquities.

Such was the petty rancour of this celebrated antiquary; but when, on a similar occasion, we find the same irritability influencing the stronger mind of SELDEN, we must forgive so inferior a one as Gough's, while we shrink into our little selves in detecting the alloy of humanity.

SELDEN had formed one of the most curious libraries in Europe, and, even at that day, it was valued at several thousands of pounds; it was the intention of this great man to have left it entire to the university of Oxford, for we had then no national library but the Bodleian. Having occasion for a manuscript which belonged to the library, they demanded of him a bond of a thousand pounds for its restitution; nor was this demand so unusual as it appears; I have seen several bonds of this nature, with the signature torn off,