Three different views of dreams are possible, and all have been held and strenuously advocated. The first is that the soul is never entirely inactive, and that dream-images proceed all the time through the mind when iu sleep. Richard Baxter held this view, and attempted to prove it by saying, " I never awaked, since I had the use of memory, but I found myself coming out of a dream. And I suppose they that think they dream not, think so because they forget their dreams." Bishop Newton says that the deepest sleep which possesses the body cannot affect the soul, and attempts to prove it by showing that impressions are often stronger and images more lively when we are asleep than when awake. Dr. Watts held the same view, and devoted a great deal of attention to it in his philosophical essays. Sir William Hamilton inclined to the same belief, because, having had himself' waked on many occasions, he always found that he was engaged in dreaming.

Baxter's theory is an assumption of which no adequate proof can be offered; and Sir William Hamilton's test is inadequate, because an instant, even the minute fraction that elapses between calling a man's name or touching his body for the purpose of awaking him and resumption of consciousness, may be long enough for a most elaborate dream. Sir Henry Holland fell asleep while a friend was reading to him. He heard the first part of a sentence, was awake in the beginning of the next sentence, and during that time had had a dream which would take him a quarter of an hour to write down.

Lord Brougham and others have maintained that we never dream except in a state of transition from sleeping to waking. Sir Benjamin Brodie, in speaking of this, says:

There is no sufficient proof of this being so; and wo have a proof to the contrary in tho fact that nothing is more common than for persons to moan, and even talk, in their sleep without awaking from it.

The third theory is that in perfect sleep there is little or no dreaming. This is supported by various considerations. The natural presumption is that the object of sleep is to give rest, and that perfect sleep would imply cessation of brain action; and it is found that "the more continuous and uninterrupted is our dreaming, the less refreshing is our sleep." Recent experiments of special interest appear to confirm this view. The effects of stimuli, whether of sound, touch, smell, sight, or hearing, in modifying the dreams without awaking the sleeper—or in awaking him — all point in the same direction; and though there is always a sense of time when awaking, which proves that the mind has to some extent been occupied, in the soundest sleep it is so slight as to seem as if the person had just lain down, though hours may have passed. Whereas, just in proportion as dreams are remembered, or as the fact of dreaming can be shown by any method, is sense of time longer. I do not speak of the heavy, dull sleep which, without apparent dreams, results from plethora, accompanies an overloaded stomach, is the residt of over-exhaustion, or occasionally supervenes after protracted vigils, but of the sound sleep enjoyed by the working-classes when in health, or by vigorous children.

The most interesting question is, Can a theory of dreams be constructed which will explain them upon natural principles, without either the assumption of materialism, or an idealism akin to superstition ? It is to be understood that no phenomena can be explained at the last analysis ; but a theory which will, without violence, show the facts to be in harmony with natural laws, or so bring them within the range of things natural that they are seen to belong to a general class, and to the relations of antecedents and consequents, is an explanation. For example, electricity defies final analysis; but its modes of action are known, and even the greatest of mysteries, the form of induction which now surprises the world in the recently invented process of telegraphing from moving trains, is as susceptible of this kind of explanation as the action of steam in propelling a train.

We begin with analogies, and find these in the effect of drugs, such as opium, alcohol, nitrous-oxid gas, hashish, etc. De Quincey describes all the experiences of dreams, both before and after he entered into a state of sleep, as resulting from the use of opium ; and the peculiar sleep produced by that drug is attended by dreams marked by all the characteristics of those which occur in natural sleep. The effect of alcohol in setting up a dream state in the mind while the senses are not locked in sleep is, unfortunately, too well known. When a certain point is reached in intoxication the will is weakened, the automatic machinery takes control, the judgment is dethroned, and images — some grotesque and others terrible — having the power of exciting the corresponding emotions, hurry through the mind until frenzy is reached, subsequent to which a heavy stupor ends the scene. When a drunken man becomes sober, his recollections of what he has done are as vague and uncertain as those of dreamers; and a similar inability to measure the flight of time, to perceive the incongruity of images, the moral character of actions, and the value and force of words, characterizes this state which attends dreaming. Ether, chloroform, and nitrous-oxid gas, when the amount administered is not sufficient to produce unconsciousness, cause similar effects. The writer, being compelled to undergo a surgical operation at a time when he was greatly absorbed in the then impending civil war, by the advice of physicians took ether, the effect of which was to lead to a harangue upon abolitionism, in which profane language was used. As the effect deepened, though it was at no time sufficient to produce absolute unconsciousness, the scene changed, devotional hymns were sung, and a solemn farewell taken of the physicians and surgeon, who were warned to prepare to die. Of all this the remembrance was like that of dreams.