cular contractions of his fingers, or, in less formal metaphysical language, that it eludes his grasp, he asks in amazement,

"Art thou not, fatal vision, sensible

To feeling as to sight? Or art thou but

A dagger of the mind; a false creation,
Proceeding from the heat-oppressed brain ?"

Occasionally the trial has served to deter an intended imposture. Thus, when a friar personated an apparition, and haunted the chamber of the Emperor Josephus of Austria, a relation of the monarch seized hold of the substantial phantasm, and flinging him out of the window, laid him pretty effectually.*

• “In most of the relations of ghosts," says Grose, “they are supposed to be mere aerial beings, without substance, and that they can pass through walls and other solid bodies at pleasure. A particular instance of this is given, in relation the 27th, in Glanvil's Collection, when one David Hunter, neat-herd to the Bishop of Down and Connor, was for a long time haunted by the apparition of an old woman, whom he was by a secret impulse obliged to follow whenever she appeared, which, he says, he did for a considerable time, even if in bed with his wife; and because his wife could not hold him in his bed, she would go too, and walk after him till day, though she saw nothing; but his little dog was so well acquainted with the apparition, that he would follow it as well as his master. If a tree stood in her walk, he observed her always to go through it. Notwithstanding this seeming immateriality, this very ghost was not without some substance; for, having performed her errand, she desired Hunter to lift her from the ground, in the doing of which, he says, she felt just like a bag of feathers."

There can be little doubt, but that the circumstance of our muscular feelings of resistance being less liable to delusion than those of sight, has given rise to a variety of notions which, from a very early period, have been entertained on the nature of spiritual beings. Thus, Lucretius, as he is translated by Creech:

"Nor must we think these are the blest abodes,
The quiet mansions of the happy gods,

Their substance is so thin, so much refin'd,

Unknown to sense, nay, scarce perceiv'd by mind;
Now, since these substances can't be touch'd by man,
They cannot touch those other things that can;

Therefore, the mansions of those happy pow'rs
Must be all far unlike, distinct from ours;

Of subtle natures suitable to their own;"

(and, as the translator quaintly adds,)

}

"All which, by long discourse, I'll prove anon." Lastly, I might observe, that the olfactory organs may occasionally be the medium through which ideas of smell are so intensely excited, as to give rise to mental illusions. Burton, on the authority of Petrus Forestus, relates, that "a minister, through precise fasting in Lent, and over much meditation, became desperate, thought he saw divells in his chamber, and that he could not be saved. He smelled nothing, as he said, but fire and brimstone, and was already in hell, and would aske them still if they did not smell as much. I told him he was melancholy, but he laughed me to scorne, and replied that hee saw divells, talked with them in good earnest, and would spit in my face, and aske me if I did not smell brimstone."

R

CHAPTER III.

THE VARIOUS DEGREES OF EXCITEMENT, OF WHICH IDEAS, OR THE RENOVATED FEELINGS OF THE MIND, ARE SUSCEPTIBLE.

"Men must acquire a very peculiar and strong habit of turning their eye inwards, in order to explore the interior regions and recesses of the MIND-the hollow caverns of deep thoughtthe private seats of fancy-and the wastes and wildernesses, as well as the more fruitful and cultivated tracts of this obscure climate."

We are now literally entering on the investigation of what the French metaphysicians name ideology, a subject which, from the manner it has been treated, has recently incurred a censure that it too well deserves. Ideology is, no doubt, a part of human physiology; but it has far outgrown its parent science in point of extent, and is still far inferior to it in the means of verification. Let the metaphysician always avail himself of the experiments of physiology as far as he is able; but let not the physiologist imagine that he can ever derive a reciprocal assistance from metaphysics. It is possible, however, to transfer credulity from one extreme to the other;-to yield a faith as implicit to the probabilities of the scientific

physiologist, as is usually required for the dogmas of pneumatology."*

These are, indeed, excellent remarks, from the just severity of which I can scarcely flatter myself with the prospect of an entire escape. The discussion will be, however, hazarded.

This investigation has hitherto been conducted upon the principle, that the various degrees of vividness of which our mental states are susceptible correspond to certain conditions of the sanguineous system; and that the natural source of the excitement which is imparted to the circulation, and of the corresponding vividness which the feelings of the mind receive, is attributable to the influence of the brain and nerves.

In the next place, several proofs were adduced in support of the conclusion, that organs of sensation were the common medium through which actual impressions were induced, and past feelings or ideas were renovated.

According, then, to this view, every organ of feeling, which is no less the organ of ideas than of sensations, must be considered as supplied with its own vital fluid, and as more or less influenced by nervous matter. To the various stimulated conditions, therefore, incidental to the vascularity of each organ of feeling, the vividness of sensations and ideas corresponds.

*Notes on Magendie's Physiology, by Dr Milligan. See his translation of this work, page 423.

I shall now attempt a description of the various degrees of excitement incidental to ideas, when exclu'sively rendered intense, premising, however, that such gradations are to be chiefly distinguished when the vision is affected.

1st Stage of Excitement.

By a principle of the mind, purely intellectual, the impressions which may at any time be induced on the seat of vision, suggest the notion of groups of sensible figures, each varying in hue and intensity, and each included in a distinct outline. While this mental operation is going on, each affected point of the retina becomes subject to a law (the consideration of which would detain us too long), whereby its vividness is considerably modified. The effect is as follows:

The nerves which impart their influence to visual sensations, first render more vivid those impressed points of the retina which give rise to the outlines of forms, and then extend their influence to the interior and central points of each figure. Thus, when we survey a landscape composed of such multifarious objects as woods, mountains, houses, or lakes, it will be found that the outlines of each of these visible forms first become distinct, or bright, and that this distinctness or vividness is in each of them gradually propagated to the interior or central parts of the figure.

In a short time, however, the outlines of each form which may have been impressed on the retina, become less clear to the vision, while the interior im