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THE CEREBRAL BATTERY, AND
on the gray substance of the brain and spinal cord, to the production of the electric force by the action of the acid solution on the metallic plates in the cells of a voltaic battery."*
Such a view may assist our insufficient conceptions; yet, in all reasonable probability, when we liken the nervous force or fluid to electricity, and the action of the cerebrum to that of an electric or galvanic apparatus, the comparison should be understood as illustrative and approximating,-as embodying only an adumbration of the truth,—not as indicating a close resemblance, still less a strict and positive identity of action.
That, in some way or other, the blood is an agent in the generation of the nervous force can scarcely be doubted. Sir Henry Holland, speaking of the intimate relations between the nervous and vascular systems, and the obvious structural connection of the nerves and blood-vessels, adds, “We cannot designate a single part in the whole economy of animal life in which we do not find these two great powers conjointly concerned, their co-operation so essential that no single function can be perfectly performed without it. The blood and the nervous force, so far as we know, are the only agents which actually pervade the body throughout; the connection of the machinery by which they are conveyed becoming closer in proportion as we get nearer to the ultimate limits of observation. Besides those results of their co-operation which have regard to the numerous other objects and phenomena of life, we cannot doubt the existence of a reciprocal action upon each other, necessary to the maintenance and completeness of their respective powers.” ...“We cannot, indeed, follow, with any clear understanding, the notion
*“ Psychological Inquiries,” by Sir Benjamin Brodie, London, 1856, vol. iii. pp. 158, 159.
HOW IT MAY POSSIBLY BE CHARGED.
of the nervous element as evolved by the action of the blood, or as actually derived from the blood, and depending for its maintenance and energy on the conditions of this fluid. Yet we can hardly doubt that mutual actions and relations of some such nature really exist. Evidence to this effect is furnished, directly or indirectly, by all the natural phenomena of health, and even more remarkably by the results of disorder and disease. The whole inquiry is of singular importance to the physiology of animal life."*
Taking into view the above remarks, and assuming Brodie's suggestion as to the electroid character of the nervous element,-bearing in mind, too, that hæmatin, one of the constituents of the blood, has seven or eight per cent. of iron, while other portions contain, in smaller quantities, other metals, and that, in consequence, we have an electroid force or agent brought into intimate relation with a metal-bearing fluid, a condition that may be supposed favorable to something resembling electrochemical action,-have we not a hint as to the manner in which (to borrow analogous terms in default of accurate ones) the cerebral battery may possibly be charged ?
How closely, when we touch on such topics, are wo approaching the confines of human knowledge! A step or two further in this direction we may, indeed, somo day advance; but what then? “The chain of our knowledge,” says Berzelius, “ends ever at last in a link unknown.” If even we could discover how this battery is charged, a deeper mystery remains still vailed; the manner, namely, in which the spiritual principle within 18 avails itself of this wonderful mechanism to produce motion and direct thought.
And another inquiry, moro immediately connecting
*" Chapters on Mental Physiology," by Sir Henry Holland, M.D., London, 1852.
the foregoing digression with the subject of this chapter, may be mooted here,-an inquiry which some will dismiss as unworthy even to be entertained, but which, nevertheless, is justified, in my eyes, by its connection with certain psychological phenomena to be presented in subsequent portions of this volume; the inquiry, namely, whether, in certain exceptional conditions of the human system, as occasionally during dreams, or under other circumstances when the will is surrendered, some immaterial principle or occult intelligence other than our own may not, for a time and to a certain extent, possess itself of the power to employ the cerebral mechanism so as to suggest or inspire thoughts and feelings which, though in one sense our own, yet come to us from a foreign
Such a hypothesis, though adopted at the present day by not a few sensible men, may, I well know, startle as incredible the majority of my readers. I remind them that the first question is, not whether it be true, but whether it be worth examining. “In the infancy of a science,” says Brewster, “there is no speculation so worthless as not to merit examination. The most remote and fanciful explanations of facts have often been found the true ones; and opinions which have in one century been objects of ridicule have in the next been admitted among the elements of our knowledge."*
If still there be among my readers those who are disposed to reject at the threshold the inquiry in question, as savoring of superstition, I pray them to postpone decision in regard to it until they shall have read the chapters which follow, especially the next, treating a subject which it is difficult to disconnect from that of sleep in the abstract; the subject, namely, of dreams.
*“The Martyrs of Science," by Sir David Brewster, 3d ed., London, 1856, p. 219.
“In a dream, in a vision of the night, when deep sleep falleth upon men; in slumberings upon the bed; then God openeth the ears of men, and seal. eth their instruction."-JOB xxxiii. 14.
MODERN writers on the phenomena of sleep usually concur in the assertion that man's sleeping thoughts are meaningless and inconsequent, and that dreams are, therefore, untrustworthy.
Such was not the opinion of our ancestors, especially in remote times. They attached great importance to dreams and their interpretation. They had resort to them for guidance in cases of difficulty or of great calamity. Thus, when pestilence spread among the Grecian host before Troy, Homer represents Achilles as proposing that method of ascertaining the cause of what was regarded as an evidence of the anger of the gods; and his reason for the proposal is,
"for dreams descend from Jove."*
Aristotle, Plato, Zeno, Pythagoras, Socrates, Xenophon, Sophocles, have all expressed, more or less distinctly, their belief in the divine or prophetic character of dreams. And even some of the ancient philosophers who denied all other kinds of divination, as some distinguished Peripatetics, admitted those which proceeded from frenzy and from dreams.t
* Homer's Iliad, Book I. line 85 of Pope's translation. † Cicero “ De Divinatione,” lib. i. & 3. See also & 25 et seq. The analogy between dreams and insanity has been often noticed. Aris
DREAMS FROM THE IVORY GATE.
It does not appear, however, that any of these philosophers went so far as to claim for all dreams a divine or reliable character. Many proceeded from the ivory gate. It was usually the vision of some seer, or augur, or priestess, occurring within sacred or consecrated ground, to the warnings of which implicit faith was attached. Plato, however, seems to intimate that all dreams might be trusted if men would only bring their bodies into such a state, before going to sleep, as to leave nothing that might occasion error or perturbation in their dreams.*
Aristotle—whose works, like Bacon's, may be said to have marked out the limits of the knowledge of his dayrestricts to certain favored individuals this faculty of prescience. His expression, literally translated, is, “And that, as to some persons, prophecy occurs in dreams, is not to be disbelieved.”ť
That the modern opinion as to the fantastic and imaginative character of dreams is, in the main, correct; that, when the senses are overcome by slumber, the judgment also, as a general rule, is either entirely in abeyance, or only partially and very obscurely active; these are facts so readily ascertained, usually by a little ac. curate observation of our own nightly sensations, as to bo
totle had already surmised that the same cause which, in certain diseases, produces deception of the waking senses, is the origin of dreams in sleep. Brierre de Boismont remarks that waking hallucinations differ chiefly from dreams in their greater vivacity. Macario considers what he calls sensorial dreams as almost identical with hallucination. Holland says that the relations and resemblances of dreaming and insanity are well deserving of notice, and adds, "A dream put into action might become madness, in one or other of its frequent forms; and, conversely, insanity may often be called a waking and active dream."_" Chapters on Mental Physiology," p. 110. Abercrombie declares that “there is a remarkable analogy between the mental phenomena in insanity and in dreaming."“ Intellectual Powers," p. 240.
* Quoted by Cicero, “ De Divinatione,” lib. i. 22 29, 30. 7 “De Divinatione et Somniis," cap. i.