Melt

“ It is surely one thing to employ fire and heat to melt mineral bodies, in supposing this to be the cause of their consolidation, and another thing to acknowledge fire or heat as having been exerted upon mineral bodies, when it is clearly proved, from actual appearances, that those bodies had been in a melted state, or that of simple fluidity. ”

“ But the intense heat of the centre of the earth is able to melt rocks, and show them as liquid lava flowing from volcanoes, and Science teaches that the solid Substance of the Earth, and other planets, suns, etc., existed in the shape of a vapor at one time, and would again take on that condition in case of a collision with another great body, which convert motion into intense heat that would first melt, and then vaporize every solid particle of which the earth is composed. ”

“ The earth is to be cleansed by fire; in other words, the elements are to be melted with fervent heat. This is the declaration of several of the prophets. David, in speaking of this period, in one of his psalms, says, the mountains shall melt like wax before the presence of the Lord when he shall come. You know how wax melts when exposed to the influence of heat. So, when the Lord comes, will the elements melt and the mountains flow down at his presence with fervent heat. ”

“ I can easily understand that you find it very difficult to see how it can be believed that the interior of the earth is solid and yet at the same time be sufficiently hot to melt. I can imagine hearing you ask if it is hot enough in the inside to melt any known materials, why it is not melted. ”

“ In the case of substances like ice, which melt at a low temperature and are easily obtained in large quantities in a state of purity, the point of fusion may be very accurately determined by observing the temperature of an intimate mixture of the solid and liquid while slowly melting as it absorbs heat from surrounding bodies. But in the majority of cases it is more convenient to observe the freezing point as the liquid is cooled. ”

“ Yet it is known to be in a state of such intense heat that some of the metals which it requires great heat even to melt are not only melted but volatilized. No one therefore conceives that there can be any life or intelligence on the sun. ”

“ The quantity of heat required to melt ice or snow is very great, as we all know by experience of the long time masses of snow will remain unmelted even in warm weather. We shall however be better able to appreciate the great effect this has upon climate, by a few figures showing what this amount really is. ”

“ For each additional atmosphere of pressure—a weight amounting to about fifteen pounds to the square inch—the temperature at which the ice will melt is lowered to the amount of sixteen thousandths of a degree centigrade. If we take a piece of ice at the temperature of freezing and put upon it a sufficient weight, we inevitably bring about a small amount of melting. Where we can examine the mass under favourable conditions, we can see the fluid gather along the lines of the crystals or other bits of which the ice is composed. ”

“ The word rendered melt, is a metaphor taken from metals, dissolving in the fire, or wax before the flame; so will the fierce and spreading fire of the last day melt down this globe, and its surrounding atmosphere.36 That the world was to be dissolved by fire was the opinion of Anaximander, Anaxiphanes, Anaxagoras, Archelaus, Diogenes, and Leucippus.37 The inference which the apostle deduces from this view of the general and final conflagration of the world, is highly impressive. ”

“ After air, we consider those bodies to be most sensible of heat, which have been recently changed and contracted by cold, as snow and ice; for they begin to be dissolved and melt with the first mild weather. ”

“ These masses of liquid rock would also tend to melt their own way upward, especially when given a lift by gases; for gases would be given off, also, in this heating and melting process, and tend to work their way toward the surface, carrying with them the liquid rock.
5. Now the greater the pressure under which a thing is kept the more difficult it becomes for it to flow; the less the pressure the more easily it flows and the longer it remains in the fluid state. So as it rose fluid rock would require less heat to keep it fluid and would have more heat left over for melting its way up. ”

“ But if an abundant supply of liquid or gaseous water is combined with cold sufficient to condense it into the solid form, it becomes fixed, and if the summer heat is insufficient to melt the excess of snow, it necessarily 295 accumulates. ”

“ There are below the crust of the earth large masses of highly heated rock that are kept solid by the enormous pressure of the overlying rocks, or otherwise they would melt,—for it is a known fact that pressure tends to prevent the melting of a solid body. ”

“ See a good summary of this idea in Black's Lectures on Chemistry, vol. i. p. 118. Contrasting his theory of heat with that previously received, he says, ‘But, were the ice and snow to melt as suddenly as they must necessarily do, were the former opinion of the action of heat in melting them well founded, the torrents and inundations would be incomparably more irresistible and dreadful. They would tear up and sweep away every thing, and that so suddenly, that mankind should have great difficulty to escape from their ravages.’ ”

“ Freeze a pot with water, and it will become as hard as a rock. Put the frozen pot on the fire: the ice will begin to break, and melt, and move; the water will begin to stir, and bubbles will rise; then, when it begins to boil, it whirls about and makes a noise. The same happens in the world from the heat. ”

“ The gas is imprisoned in small thin globes of ice which shatter when they strike the rug, and melt in a few seconds, leaving no trace other than a few drops of water which quickly evaporate or are absorbed by the rug fibres. These globes are kept in a small refrigeration plantwhich is just above my head, and probably quite thoroughly insulated against heat. The intense cold in this plant is produced by a substance which is not new to science, but the use of which for this particular purpose is quite new. ”

“ Because the rough, dark iron of the tea-kettle absorbs the heat from the fire, and gives it off rapidly to the water contained in the kettle. The iron is also a good conductor of heat; therefore, the heat from the fire passes rapidly through it to the water.
Why does black cloth, when spread on the snow, cause the snow to melt more rapidly? ”

“ However, we find that when a body is melting, vaporizing, or otherwise suffering an abrupt change in physical properties, a quantity of heat is absorbed which disappears without changing the temperature of the body. ”

“ Heat opens and separates parts of condensed bodies, and therefore bodies that boil, grow soft, or melt, require a greater space than before; but, on the contrary, the parts of the body that are condensed or freeze are contracted closer to one another, and leave those vessels and places from which they retired partly empty. ”

“ There are secret conduits or rivulets of the liquid matter, which communicates fire and heat into all parts more or less, and melts the stones and cinders by fits in those places where it toucheth them, over and over again; where it meets with rocks or houses of the same matter (as many are) , they melt and go away with the fire; where they find other compositions, they turn them to lime or ashes (as I am informed) . The composition of this fire, stones, and cinders, are sulphur, nitre, quicksilver, sal ammoniac, lead, iron, brass, and all other metals. ”

“ When cold, the unnecessary metal is cut away, and the fragments are as perfectly united as if they had been originally cast in one piece.
The sudden consolidation, by physical force, of pounded ice or snow appears to me to arise from the first effect of the pressure producing heat, which melts a small portion into water, and brings the particles of ice or snow nearer to each other. The portion of water thus produced then, having its heat abstracted by the ice, connects the particles of the latter more firmly together by freezing. ”

“ So, the heat that has been applied to the melting ice has been utilized during the process of its liquefaction in rearranging the water molecules and putting them in a state of strain, so to speak, like the weight that is wound up to a certain height. There is a certain amount of potential energy that is stored in the molecules of water that will be given up and become active energy in the form of heat, if the water is again frozen. ”

“ The result is that a snow coating is in effect an admirable blanket. When the sun shines upon it, much of the heat is reflected, and as the temperature does not penetrate it to any depth, only the superficial part is melted. This molten water takes up in the process of melting a great deal of heat, so that when it trickles down into the mass it readily refreezes. ”

“ If you would reduce the six cold metals to fluidity, whether it be ♃, ♀, ♄, ♂, ☽, ☉, it is to be done by the heat of the fire, for metals are not melted with cold Snow or Ice, but are hardened thereby. Now, as soon as they are melted by the fire, and that the heat ceaseth, the cold rusheth in, whereby the metal stands still, grows stiff, dies, and remains immovable. And because that ☿ is alwaies fluid and living, tell me, I pray, whether or no such a thing proceeds from heat or cold? ”

“ But imagine heat so great that masses of iron and copper are not only melted but turned into vapor. Then you have some idea of the intense heat that prevails on the stars. The rains that fall on earth are made up of drops of water, but the rainfalls on the stars must be drops of melting iron, while the clouds that form are sheets of molten metal. ”

“ Some have even assumed the melting point to be less than thirty miles, when “the next contiguous matter is in a state of fusion, at a temperature probably higher than any that man can produce by artificial means, or any natural heat that can exist on the surface.” ”

“ To show the poor qualities of water as a conductor of heat, take a long glass tube and fill with water. Then put a piece of ice in one end. The water at the other end may now be brought to the boiling point by means of the flame of a lamp, ere the ice at the other end is melted.
Every one is familiar with the fact that heated air rises ”

“ Solids differ from one another in the temperatures at which they become liquid. These temperatures are called their melting points. Thus the melting point of ice is 32°; that of lead 612°; that of gold 5237°. [3] The heat which is supplied to a body during the processes of fusion or vaporization, and which does not affect the thermometer, or increase the temperature of the body fused or vaporized, is said to become latent. It can be proved to exist in the body fused or vaporized, and may even be taken from that body. ”

“ The process of melting ice is very slow, because every portion must absorb or render latent a certain quantity of heat before it can take the liquid state—hence the difficulty of melting blocks of ice when they are surrounded with non-conducting materials ”

“ The heat of the earth and that derived from the friction of the glacier and its broken fragments against the rock on which it rests, as well as from the friction of its own fragments, slowly melts the ice, and thus diminishing the amount of its support, the ice above cracks and falls down upon the earth, again to be melted and again to be broken. ”

“ The ordinary account given of their structure is, I believe, that the moisture raised from the earth by the sun’s heat becomes visible by condensation at a certain height in the colder air, that the level of the condensing point is that of the cloud’s base, and that above it, the heaps are pushed up higher and higher as more vapor accumulates, till, towards evening, the supply beneath ceases; and at sunset, the fall of dew enables the surrounding 123 atmosphere to absorb and melt them away. ”

“ Thus the contrary operations of heat, which hardens some substances and melts others, are easily reconciled; since in the former the spirit is discharged, in the latter it is excited and detained; whereof the melting is the proper action of the heat and spirit; the hardening is the action of the tangible parts only on occasion of the discharge of the spirit. ”

“ Again, ice being a
substance which contracts in melting, the effect of pressure is
to facilitate melting, lowering its freezing point. But
64
so soon as a little melting occurs, the resulting liquid calls on
the residual ice for an amount of heat equivalent to the latent
heat of liquefaction, and so by cooling the whole, retards the
change.
Such particular cases illustrate a principle controlling the
interaction of matter and energy which seems universal in
application save when evaded, as we shall see, by the ingenuity
of life. ”

“ Other things, such as stones, are melted only by terrific heat.
When the little particles of water that make up the clouds become very cold, they freeze as they gather and so make snowflakes. When the little particles of water in the air, that usually make dew, freeze while they are gathering on a blade of grass, we call it frost. When [pg 98] raindrops are carried up into colder, higher air while they are forming, they freeze and turn to hail. When snow or frost or hail or ice is heated, it melts and turns back to water. ”

“ The cold you experience consists in the loss of caloric that your hand sustains in an attempt to bring its temperature to an equilibrium with the marble. If you lay a piece of ice upon it, you will find that the contrary effect will take place; the ice will be melted by the heat which it abstracts from the marble. ”

“ On the other hand, the heat going out from the earth, the store accumulated in its superficial parts in the last warm season, together with the small share which flows out from the earth's interior, is held in by this blanket, which it melts but slowly. ”