Michael Faraday

“ You will not mind my using this word, for when I say that this penny-piece gravitates, I mean nothing more nor less than that it falls toward the earth, and, if not intercepted, it would go on falling, falling, until it arrived at what we call the centre of gravity of the earth, which I will explain to you by-and-by.
I want you to understand that this property of gravitation is never lost; that every substance possesses it; that there is never any change in the quantity of it; and, first of all, I will take as illustration a piece of marble. ”

“ Even when we can see the stars clearly on a bright night, it is not a pure atmosphere. The light of a light-house, more than any other, is liable to be dimmed by vapours and fogs; and where we most want this great power, is not in the finest condition of the atmosphere, but when the mariner is in danger—when the sleet and rain are falling, and the fogs arise, and the winds are blowing, and he is nearing coasts where the water is shallow, and abounds with rocks,—then is his time of danger, when he most wants this light. ”

“ Shall we educate ourselves in what is known, and then casting away all we have acquired, turn to our ignorance for aid to guide us among the unknown? If so, instruct a man to write, but employ one who is unacquainted with letters to read that which is written; the end will be just as unsatisfactory, though not so injurious; for the book of nature, which we have to read, is written by the finger of God. Why should not one who can thus lift a table, proceed to verify and simplify his fact, and bring it into relation with the law of Newton? ”

“ Just what occurs in my lungs—taking in oxygen from another source, namely, the atmosphere—takes place here by a more rapid process.
You will be astonished when I tell you what this curious play of carbon amounts to. A candle will burn some four, five, six, or seven hours. What, then, must be the daily amount of carbon going up into the air in the way of carbonic acid! What a quantity of carbon must go from each of us in respiration! What a wonderful change of carbon must take place under these circumstances of combustion or respiration! ”

“ Indeed, it is the great beauty of our science, CHEMISTRY, that advancement in it, whether in a degree great or small, instead of exhausting the subjects of research, opens the doors to further and more abundant knowledge, overflowing with beauty and utility, to those who will be at the easy personal pains of undertaking its experimental investigation. ”

“ Why did they not inform us of the possibility of photography? or when that became known, why did they not favour us with some instructions for its improvement? They all profess to deal with agencies far more exalted in character than an electric current or a ray of light: they also deal with mechanical forces; they employ both the bodily organs and the mental; they profess to lift a table, to turn a hat, to see into a box, or into the next room, or a town:—why should they not move a balance, and so give us the element of a new mechanical power? ”

“ It owes its lustre at night-time to the very flame shining upon it. The flame shines in darkness, but the light which the diamond has is as nothing until the flame shine upon it, when it is brilliant again. The candle alone shines by itself, and for itself, or for those who have arranged the materials. Now, let us look a little at the form of the flame as you see it under the glass shade. It is steady and equal; and its general form is that which is represented in the diagram, varying with atmospheric disturbances, and also varying according to the size of the candle. ”

“ I might touch it with the wire, or with my finger, and if I did so quickly, I should merely burn the surface of the skin; whereas if I touch that cylinder, however rapidly, with my finger, the electricity is gone at once—dispersed on the instant, in a manner wonderful to think of.
I must now take up a little of your time in showing you the manner in which these powers are transferred from one thing to another; for the manner in which force may be conducted or transmitted is extraordinary, and most essential for us to understand. ”

“ I am going to shew you how, by means of a little steam, I can completely obscure this glorious sun, this electric light which you see. The cloud now obscuring the light on the screen is only such a cloud as you see when sitting in a train on a fine summer’s day. You may observe that the vapour passing out of the funnel casts as deep a shadow on the ground as the black funnel; the very sun itself is extinguished by the steam from the funnel, so that it cannot give any light; and the sun itself, if set in the light-house, would not be able to penetrate such a vapour. ”

“ Looking forward to such a table as of extreme utility (if well-constructed) in developing the intimate relation of ordinary chemical affinity to electrical actions, and identifying the two, not to the imagination merely, but to the conviction of the senses and a sound judgement, I may be allowed to express a hope, that the endeavour will always be to make it a table of real, and not hypothetical, electro-chemical equivalents; for we shall else overrun the facts, and lose all sight and consciousness of the knowledge lying directly in our path. ”

“ The first step in correction is to learn our deficiencies, and having learned them, the next step is almost complete: for no man who has discovered that his judgment is hasty, or illogical, or imperfect, would go on with the same degree of haste, or irrationality, or presumption as before. I do not mean that all would at once be cured of bad mental habits, but I think better of human nature than to believe, that a man in any rank of life, who has arrived at the consciousness of such a condition, would deny his common sense, and still judge and act as before. ”

“ It will be my place, when next we meet, having pointed out these anomalous actions, to shew you that none of these extra and strange effects are met with by us—that none of these strange and injurious actions take place when we are burning, not merely a candle, but gas in our streets, or fuel in our fireplaces, so long as we confine ourselves within the laws that Nature has made for our guidance. ”

“ The theory of definite electrolytical or electro-chemical action appears to me to touch immediately upon the absolute quantity of electricity or electric power belonging to different bodies. It is impossible, perhaps, to speak on this point without committing oneself beyond what present facts will sustain; and yet it is equally impossible, and perhaps would be impolitic, not to reason upon the subject. Although we know nothing of what an atom is, yet we cannot resist forming some idea of a small particle, which represents it to the mind ”

“ The world little knows how many of the thoughts and theories which have passed through the mind of a scientific investigator have been crushed in silence and secrecy by his own severe criticism and adverse examination; that in the most successful instances not a tenth of the suggestions, the hopes, the wishes, the preliminary conclusions have been realized. And is a man so occupied to be taken from his search after truth in the path he, hopes may lead to its attainment, and occupied in vain upon- nothing but a broad assertion? ”

“ Thus, you have seen the force of electricity acting in other ways than in attracting: you have also seen it combine matters together, or disunite them, by means of its action on the chemical force; and in this case, therefore, you have an instance in which these two powers are related. But we have other and deeper relations than these; we have not merely to see how it is that one power affects another—how the force of heat affects chemical affinity, and so forth—but we must try and comprehend what relation they bear to each other, and how these powers may be changed one into the other ”

“ Here is our fuel, the coal-gas; and here our oxygen. Having thus my power of heat, I apply it to the iron, which, as you see, soon gets red-hot. It is now flowing about like a globule of melted mercury. But observe, I cannot raise any vapour: it is now covered with a coat of melted oxide, and unless I have a great power in my blowpipe, it is hardly possible to break through it. Now, then, you see these beautiful sparks: you have not only a beautiful kind of combustion, but you see the iron is being driven off, not producing smoke, but burning in a fixed condition. ”

“ If, therefore, we desire to consider a proposition respecting the employment or evolution of power, let us carry our judgment, educated on this point, with us. If the proposal include the double use of a force with only one excitement, it implies a creation of power, and that cannot be. If we could by the fingers draw a heavy piece of wood or stone upward without effort, and then, letting it sink, could produce by its gravity an effort equal to its weight, that would be a creation of power, and cannot be. ”

“ Here I have the rays once more bent on to the screen, and you see how wonderfully and beautifully that piece of glass not only bends the light by virtue of its attraction, but actually splits it up into different colours. Now, I want you to understand that this piece of glass [the prism] being perfectly uniform in its internal structure, tells us about the action of these other bodies which are not uniform—which do not merely cohere, but also have within them, in different parts, different degrees of cohesion, and thus attract and bend the light with varying powers. ”

“ So he is able to fuse a large body of platinum in this manner. When the platinum is melted, he takes off the top and pours out from the bottom piece, like a crucible, and makes his cast. This is the furnace by which he fuses his forty pounds or fifty pounds of platinum at once. The metal is raised to a heat that no eye can bear. There is no light, and shadow, no chiaro-oscuro there; all is the same intensity of glow. You look in, and you cannot see where the metal or the lime is; it is all as one. ”

“ Unlike oxygen, which is a supporter of combustion, and will not burn, hydrogen itself is combustible. There is a jar full of it; and if I carry it along in this manner, and put a light to it, I think you will see it take fire, not with a bright light—you will at all events hear it, if you do not see it. Now, that is a body entirely different from oxygen: it is extremely light; for although yesterday you saw twice as much of this hydrogen produced on the one side as on the other, by the voltaic battery, it was only one-eighth the weight of the oxygen. ”

“ When we think of the laws of nature (which by continued observation have become known to us) as the proper tests to which any new fact or our theoretical representation of it should in the first place be subjected, let us contemplate their assured and large character. Let us go out into the field and look at the heavens with their solar, starry, and planetary glories; the sky with its clouds; the waters descending from above or wandering at our feet ”

“ Is it not beautiful to think that such a process is going on, and that such a dirty thing as charcoal can become so incandescent? You see it comes to this—that all bright flames contain these solid particles; all things that burn and produce solid particles, either during the time they are burning, as in the candle, or immediately after being burnt, as in the case of the gunpowder and iron-filings,—all these things give us this glorious and beautiful light. ”