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ther in a different form, in a different dress, under different circum
"You know that if you suspend a magnet loosely, so that it can asily move about, one end always points to the north, and is thereire called the north pole of the magnet, while the other, pointing to he south is called the south pole. You also know that if you place bar of iron against a magnet it also becomes for the time being a agnet, is magnetized, as the phrase is, and has in turn its own north od south poles. The part that is next to the original magnet, becomes pole opposite in nature to that pole of the magnet against which it is laced. If you join the bar on to the north pole of the magnet, the learest part of it becomes a south pole, and the furthest a north vole, so that the magnet and bar form together one large magnet, till with a south pole at one end and a north pole at the other. If lou join on another bar, that too will become a magnet, and will lave also its poles arranged in the same way. To that you may add a third, and so on for any number, till at last you get a long, thin magnet, but still with the north pole at one end and the south pole at the other. Suppose now you have a series of bars without any nagnet. They will then be simply a row of bars, without any poles or any other virtues except such as belong naturally to iron. If low you suddenly magnetize one of the two end bars, what will be he result? The next bar will immediately become a magnet, will have its poles, will assume a polar arrangement, as the philosophers say. But directly it has done so, the next will do in turn exactly the same thing, and then the next, and so on until you come to the end of the row. What you did to the first bar will be felt by all the rest, one after the other. There is no necessity here to imagine any wonderful Huid passing along. It is simply the transmission of a certain effect along a row. If you were to pinch the top boy in a class at school, and whisper in his ear, “Pass it on," it would not be long before the bottom boy had received a pinch. Yet you would never think of saying that the pinch had passed in a fluid form along the form. Yet magnetism is very much the same thing. You pinch, that is , you magnetize the top bar and the bottom bar soon feels the effect. You have no need to say, “Pass it on," Iron always will pass it on, cannot help doing so. Many substances, the majority of substances in fact, will not pass it on.
They cannot do it. Their particular constitution prevents them doing so, in other words, they are incapable of being magnetized.
"This is the true way of looking at magnetism, and the facts of electricity may also be put in the same light. If you dip the ends of two slips of copper and zinc into a cup containing two acid liquids, you get a similar polar arrangement. The end of one metal becomes a kind of pole, and the end of the other an opposite pole. They are, however, no longer called north and south, but negative and positive. But directly one end of a slip becomes one sort of pole
, its other end is also affected, but in an opposite way, and becomes the other sort of pole. The whole slip has become polar. And the other slip behaves exactly in the same way, with this difference only, that as the end in the acid is the opposite pole to the end of i the other slip in the acid, so its end out of the acid is likewise an opposite pole to the end of the other slip out of the acid. If now you join a row of pieces of metal to each slip, the effect begun in the acid will be passed on through each series, just as in the case of the magnets. The end of the last piece in each row will be of a pole opposite in nature to the pole that is in the liquid. The zinc metal being positive in the acid, the end of the series attached to it will be negative, while the end of the copper series will be positive. For convenience sake, you may replace the row of plates by pieces of wire, which, if you rightly consider them, are nothing but a series of small, very small plates called atoms. Each atom becomes polar, becomes positive at one end and negative at the other; becomes so because it is its nature, and in the nature of its fellow atoms to receive and pass on the effect started in the acid liquid. It will do so, that is to say, if the body of which it is an atom be made of the right stuff. Some bodies are not made of the right stuff, are so constituted that they will not pass on the polar influence, and are consequently called non-conductors. Those that are of the right stuff are called conductors.
“Such is galvanism, such is the nature of the galvanic battery, a peculiar arrangement started at one point and passed on through particular bodies towards another distant point. It is in the struggles to pass on that the effects, the outward visible tokens of what we call galvanic action, are produced. The two ends of the wires attached to the metals are two different poles, and if they are made to touch a substance which is of such a disposition as to be upset when it is asked to pass the action on, of course there is a disturbance. And just as that action began in what is called chemical decomposition so it may end. The polar arrangement was caused by the acid liquid attacking, changing, decomposing the plate of zinc. Every moment a process of that kind takes place
, every moment the polar condition is passed along the wires
. There is a continual succession of these changes running along the wires, there is what is ordinarily called a galvanic current rushing through them. As each change reaches the end of the wires, it is lost in producing the very same thing that gave it birth, namely, chemical decomposition, or in giving rise to some other disturbance among the molecules of the body it reaches. It is only when it is in a position to do some mischief of this kind that the galvanic action can continue. Directly the metals in the liquid become polar, the ends of the wires become polar too, and when they have
ince become so nothing further can ensue, all further action in the lattery is at once stopped. Give the wires something, however, ipon which their polar influence can work its will, action begins gain, and will go on as long as there is stuff within the battery to rork and stuff outside to work upon. "But what is true in this way of galvanic electricity is also true of rictional electricity, such as is produced by the glass cylinder and ilken rubber. They are in their fundamental nature the same thing roduced in different ways. In neither case is there any necessity D suppose the existence of any mysterious fluid. " In every chemical action, in every case of friction, in almost every ction of body upon body, this polar arrangement of electricity is brought about; only in very many cases it is lost as soon as it is sroduced. In the human body, with its ceaseless changes, elecricity is continually being generated. From every smallest piece of our frame, we might trace, if we could prevent its being absorbed as soon as it is born, and obtain a very large amount of it in a very short space of time. As for losing our vital electricity, and requiring a fresh supply of it, we should want a gigantic belt indeed to make food the quantity we lose in a single minute. But when we say ose, we do not mean really lose. It is only changed into something nore needed by the economy. If it became and remained mere :lectricity, available for no purpose, convertible into nothing else, it vould be lost indeed. Happily, as it is, the electrical condition-the polar condition is only just one of the phases into which changing lature passes here and there for an instant, as she works her way brough all those wonderful mutations of matter that we call animal ife
. There is no such thing as the electric fluid. There is no such hing as vital electricity, distinct from any other kind of electricity. There is no such thing as a man having, either in any part of him ir in his body as a whole, too much or too little electricity. Should ae, or any part of him, become even for a moment too distinctly polar—too positive or too negative--the balance would soon be restored again in the one case, by the rest of his body; in the other by the grand equalizing polar arrangements of the earth on which he treads. Nor would such a condition, if attainable, at all promote his general welfare or increase his strength. If you insulate a man by placing him on a stool with glass non-conducting legs, you may fill him, through the friction machine, with either positive or negative electricity ; may make him so polar, either negatively or positively, that you may draw sparks from his knuckles. Yet he will not feel the slightest difference in himself; will not be a whit stronger or weaker, better or worse.
" It is quite true, that in particular organs of the body—in the nerves and in the muscles——there are during life, many electrical currents passing to and fro from point to point; (currents that vary in behaviour according as the part is, for the time being, actively employed or at rest; currents which last only during life, and vanish at the death. It is quite true, that whenever a movement is made, whenever the arm is raised or the head bent, an influence starts from the brain and runs down the nerves to the muscles, in a manner very similar to that in which the electric influence starts from the battery and runs along the conducting wires. It is quite true, that by means of electricity the just dead corpse may be excited into ghastly imitations of the gestures of life. But it is quite untrue to suppose, that in these cases electricity causes the whole
, or the greater part, of the excitement. Every muscle and nerve is during life, the seat of active chemical and physical change the scene of a fierce conflict of atoms. Out of this conflict there must necessarily arise many electric currents, which are ordered and disposed of according to fixed laws. While the muscle and nerve are at rest, the changes that are taking place are of one kind. Directly action occurs, however, immediately the nervous influence runs down the nerve, the muscle shortens, and movement and the other manifestations of visible life are brought about. Then there is a change in the kind of action, there is a tide in the conflict of the atoms, and the electric currents, which are in one sense but signs of the progress of the battle, swing round too. Then again, on the other hand, the electric current, as it may be produced by chemical and other molecular changes, so it is also capable of producing chemical and molecular changes in turn. Hence, when brought to bear upon a living part where the struggle of atoms is so intense, so complicated, and so strong, that a very little will turn the tide, it will sway the order of changes, and imitate the living influence itself. Iouch a nerve with the galvanic wires ever so lightly and ever so momentarily, an action is at once set up which, passed along the living tissue, brings the muscle into contraction. But this takes place not because the galvanism is potent, but because the nerve and muscle are weak, are susceptible of the slightest force. Nor is there any peculiar virtue in the galvanism to produce this
. Prick the nerve with a needle, or touch it with a drop of acid, the effect is just the same. The power that is shown by the muscle in contracting as it raises a weight or moves the body does not arise from the galvanism or the prick, or from anything else which started the process. It comes from its own atoms where it has been stored up amid the changes through which thc flesh grew out of the food. One has no more right to say that the galvanism caused the move. ment than that the whip caused the cart to go when it was applied to the horse. Indeed, electricity is in this case nothing more than a whip, and philosophers always speak of it when used in this way as a stimulus or goad. All living tissues bear this chief token, that they are sensitive to stimuli, that they have a certain amount of power of work in them, but require the whip to bring it out.
Very mysterious indeed is this property, and its influence and workng may be traced far and wide through all the phenomena of life.
" It is as a stimulus that galvanism becomes a remedial agent in he hands and arms. It can impart no fluid, bestow no power, iring no new force. It cannot of itself renew a wasted muscle, trengthen a palsied arm, or create a new skin and fresh hair, But it can awake the power that is not dead but only sleeping ; it an brighten up the faculties that were rusting for want of use; it an draw the fertilizing agencies towards parts they had begun to hun; it can whip up the sluggish forces of life and set them on heir way again."
MAN HIGHER THAN THE ANGELS.
A BIBLICAL STUDY.
The worship of angels was one of the many strange errors that ound their way into the early church. It was introduced, in all robability, not from the Jewish but the heathen side, and grew out f those speculations of heathen philosophy, which lay at the root f all the Gnostic systems of the first centuries. The heathen aythology, with its lords many and gods many, its satyrs, dryads, ymphs, and demigods, formed a much more likely substratum for he worship of angels than the simple angelology of the Old Testalent; and the possibility of combining the subordinate worship of ngels with the supreme worship of God, would suggest itself more radily to a Gentile than to a Jewish mind. It was probably in ime such way as this that the practice arose. The Gospel of 'hrist had swept away the hosts of varied forms, with which the eathen peopled the whole interval from man to God. The blank oid was intolerable; from inablility to discern how Christ, and Christ alone filled up the whole, a new mythology arose, and the ngels of the Old Testament itself peopled the void with new bjects of reverence and even of worship.
The worship of angels lias long since passed away. But the zelings and notions out of which it sprang are with us still. There š the same thought of a vast void between man and God, which atermediate orders can and must fill up; the same notion that ngelic hosts rise far above us, in nature and in office superior to nan; and the same feeling of reverential awe, which nothing short f God ought to awaken, and which led in the Colossian Church to he “voluntary humility and worshipping of angels,” so strongly condemned by the Apostle Paul (Col. ii. 18). But is there any foundation for such thoughts as these? Is there