PHYSICAL ORGANISMS AND THE MIND.

SIR BENJAMIN C. BRODIE, BART., D.C.L., ETC. 'During what may be called sound sleep, those impressions on the external senses of which we take cognizance while we are awake are altogether unnoticed. But it is not so with regard to the changes which are taking place in the brain itself; and that which constitutes the imagination during the day is the foundation of our dreams at night. There is, however, a great difference in the two cases. The imagination, while we We can arrest

are awake, is regulated by the will. visions as they pass before us, compare

them with each

But it is not so

other, and dismiss them as we please. with our dreams at night. Here the visions which arise, uninfluenced by the will, succeed each other according to no rule with which we are acquainted, forming strange combinations, often wholly unlike anything that really occurs, and not less differing from reality in the rapidity with which they come and depart. You are called in the morning, and fall asleep again. Perhaps you have slept only one or two minutes; but you have had a long dream. The laté Lord Holland was accustomed to relate the following anecdote of what had happened to himself. On one occasion, when he was much fatigued, while listening to a friend who was reading aloud, he fell asleep, and had a dream,

CROWDING OF EVENTS.

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the particulars of which it would have occupied him a quarter of an hour or longer in writing. After he awoke, he found that he remembered the beginning of one sentence, while he actually heard the latter part of the sentence immediately following it, so that probably the whole time during which he had slept did not occupy more than a few seconds. Mr. Babbage had a similar opportunity of measuring the real duration of a dream. While travelling with a friend in Italy, being much wearied, he fell asleep, and dreamed a succession of events as having occurred in England. When he awoke, he heard the concluding words of his friend's answer to a question which he had just put to him. I mention these things, however, only in the way of illustration, and not as being of any very unusual occurrence. Similar instances are referred to by Lord Brougham in his "Discourse on Natural Theology," and may, if we look for them, be found within the range of our individual experience. If we were to pursue this subject, it would lead us to some curious speculation as to our estimate of time, and the difference between the real and the apparent duration of life. The measure of time which we make by our own feelings is a very different matter from that which uncivilised man makes by the moon and stars, and which we now make by clocks and almanacks. The apparent duration of life is longer or shorter in proportion as a greater or

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VARIOUS RESULTS OF IMPRESSIONS.

smaller number of different states of mind follow each other in succession. To a child, whose imagination is constantly excited by new objects, and whose temper passes more easily from one passion to another, a year is a much longer time than to the grown-up man. As we advance in age, so do the years pass more rapidly. We may suppose the life of a butterfly, which exists only for a single season, to be apparently longer than that of the slowly-moving tortoise, whose existence is prolonged for one or two centuries; and that there is a similar difference, though in a less degree, between the life of the enterprising man, whose progress is crowded with events, and with alternate hopes and fears, and that of another who, with more limited desires, keeps "the even tenor of his way."

'During sleep ordinary impressions pass unnoticed. But impressions of a stronger kind rouse the attention, and in so doing put an end to sleep; while those of an intermediate kind affect us in another way, by giving a peculiar character to our dreams. A remark was made in one of our former conversations, referring to acid in the stomach, and some other cases, as illustrating the subject. It occurs to me to add another example to those which have been adduced. It lately happened to myself to dream that some one had given me a shellfish in a shell something like a muscle; that I ate it; and that, after it had been swallowed, I felt it to be

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very acid, and that it produced a pain in my throat. When I awoke, I found that I laboured under a sore throat, which must have suggested the dream. It is a curious fact that we may have a long dream in the act of awaking from our sleep. A military officer informed me that, while serving in the Peninsular war, he had frequently been roused from his sleep by the firing of a cannon near his tent; and that he had a dream, including a series of events which might be distinctly traced to the impression made on his senses by the explosion. Facts of this kind have inclined Lord Brougham to the opinion that we never dream except while in a state of transition from being asleep to being awake. But I own that this seems to me to be a mistake. First, there is no sufficient proof of its being so; and secondly, we have a proof to the contrary in the fact that nothing is more common than for persons to moan, and even talk, in their sleep, without awaking from it. Even in the case of a dog, who is sleeping on the before the fire, if you watch him, you can scarcely doubt that he is sometimes dreaming, though he still remains asleep. I should myself be more inclined to doubt whether we ever sleep without some degree of dreaming. At any rate not to dream seems to be, not the rule, but the exception to the rule; for it rarely happens that we awake from sleep without being sensible of some time having elapsed since we fell asleep; which

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DREAMS AND MEMORY.

is in itself a proof that the mind has not been wholly unoccupied. That on such occasions we have no distinct recollection of our dreams proves nothing. Referring again to the instance of persons who talk in their sleep, we often find that they have not the smallest recollection of their having dreamed afterwards. It is only those dreams which affect us very strongly, and which occur immediately before we awake from sleep, that we really remember; and even of these the impression is not in general sufficient for us to retain it for more than a very few minutes. If a dream be remembered longer, it is only because we have thought of it after it occurred, and have thus given it a place in our memory which it could not have obtained otherwise. And this leads me to observe that, although memory does so little as to dreams, dreams throw some light on this wondrous faculty. I know not, indeed, what has happened to others, but it certainly has happened to myself to dream of something that had occurred in my boyish days, and of which, as it had not been present to my thoughts for many years, it might well be supposed that it was wholly forgotten. On one occasion I imagined that I was a boy again, and that I was repeating to another, boy a tale with which I had been familiar at that period of my life, though I had never read it nor thought of it since. I awoke, and repeated it to myself at the time, as I believe, accurately enough,