Fissile material

“ Arrangements for the further settling and collection of the flue-dust are essential in connection with modern blast-furnace plants, where blast pressures of from 40 to 50 ozs. per inch are employed and where it is often found economical to work with [Pg 168] as much fine material as possible, either as such or in an agglomerated form; where too, the dropping of charges from some height and the agitation caused by the blast are practically unavoidable. ”

“ As the flow from the iron notch decreases, the iron, and a small quantity of cinder or slag, which has been chilled by coming in contact with the cold surface of the trough, adhere to its sides and bottom. When the molten iron on the hearth is about exhausted, the blast is increased, and the material left on the hearth is blown out through the iron notch into the sand-trough. This also cools in the trough, and thus is formed what are known as trog h runners, consisting of iron and slag, which have been forced through the iron notch by letting on the blast as just mentioned. ”

“ The trapping device is an important and essential feature in connection with the modern practice of rapid and continuous running, the principle being to arrange a sufficient height of molten material at the outer side of the slag opening to overcome the inside blast pressure, and thus prevent the escape of blast with its attendant inconveniences and danger. ”

“ When the fissures are deep and wide and traverse different formations, conditions are afforded for very complex deposits, and for the concentration of rare and valuable material originally dispersed through a great mass of rock. Ore deposition in such veins is usually treated as a theme by itself, but it is really but a declared expression of the work which the percolating waters are doing throughout all the rocks which they penetrate. Most of the fine crystals that grace mineralogical collections were formed in cavities and fissures by deposition from circulating mineralized waters. ”

“ The violence of the operation, coupled with the intense heat, fuses everything—furnace, projectiles, electric wires, fire-brick, even asbestos, into a single mass. The cube is opened, and this mass, white-hot, is dropped into cold water. This increases the pressure until the mass is cool. ”

“ Now, the great improvement of chemistry has been to extract from the nitre the gross material which is contained in the proportions—2-5ths impurities, and 2-5ths condensed air; thus, half the quantity being useless, the extraction of these alloys gives a greater quantity of condensed gases in the same quantity of matter; for if we take away 2-5ths of the proportions of useless [266] matter, and supply its place with 2-5ths more condensed air, we thus get 4-5th explosive matter in the same bulk of material, and thus simply obtain an immense increase of power without an increase in bulk. ”

“ By the action of compression and dislocation not only are the major masses folded or broken, but their individual constituents are brought into new relations both as regards their external conditions and internal molecular arrangement. Where lateral pressure has been active as regards the finer-grained rocks, such as clays, the individual particles arrange themselves with their longer axes at right angles to the pressure, the result being the production of a fissile structure or cleavage, totally distinct from the original bedding-planes of the strata. ”

“ Shafts are sunk, or tunnels driven, in the mass of rock to be blasted, and, connected with them, a number of chambers are excavated to receive the charges of explosive. The preparation for such blasts may occupy months, and many tons of gunpowder or dynamite are at times exploded simultaneously, breaking or dislodging thousands, or even hundreds of thousands, of tons of rock. This method is adopted for getting stone cheaply, as for building macadamized roads, dams and breakwaters, obtaining limestone for blast furnace flux, and occasionally in excavating large railway cuttings. ”

“ The exact opposite is the truth. When a mass of explosive is detonated, it is converted practically instantly into a ball of incandescent gases and vapors under very high pressure. When confined the gases act to disrupt their container.
When a large steel projectile is charged with a high explosive, like picric acid, and the explosive detonated, the walls of the pro [10] jectile are not only broken but they are also torn, twisted and shredded, and so quick is the action that the inner surface of the metal is compressed and densified against the outer metal. ”

“ Gemmation may be correlated with multiple nuclear fission in such a way that buds are formed over the whole body surface of the organism, which thereby undergoes a process of simultaneous multiple fission into numerous daughter-individuals. Rapid multiple fission of this kind is termed sporulation, and is a form of reproduction which is of common occurrence, especially in parasitic forms. ”

“ The whole series of stratified masses will be affected by the tension in the same manner, but under some conditions the fissures may not reach to the surface. The fissures will be of nearly uniform width at all depths, except that unequal elasticity in the dislocated strata will cause some differences. It is not inconsistent with mechanical principles to admit that more than one parallel fissure may originate simultaneously, and they may be subsequently prolonged, so that many parallel fissures (especially below the surface) may exist together, the fruit of one general action. ”

“ The proportion of charcoal is considerably increased, and the blast is applied more slowly than when wrought iron is required. The only apparatus wanted for the manufacture is a small clay furnace, four feet high by one to two broad, like that used by the South Africans; charcoal for fuel, and a skin with a pipe or twyers of refractory clay for the blast. [412] For the anvil a stone-slab suffices, and for the hammer a cube of stone with sides grooved for fibre-cords.
The ‘Dark Continent’ is emphatically an iron-land, and all explorers have noticed its abundance of ore. ”

“ The effect, therefore, that results from the inflammation of fire-works, in which iron or steel forms a constituent part, is nothing more than a vivid combustion of the metal; and during that process it becomes oxidized, as it does not form an acid with oxygen, like arsenic, antimony, and some other metals. ”

“ Fire hardens the clay and dissolves the metal. This plate of tempered steel, on which I am going to etch, shall corrode, effervesce, be absolutely decomposed by the action of a few drops of nitrous acid, which has no effect whatever on this lump of wax. ”

“ They are still childish and primitive. Our blast-furnaces are mere adaptations of the prehistoric pits, changed into hollow columns and enlarged according to requirements. And one continues throwing in the ore and the combustible pell mell, and burning them together. One might take such a furnace to be some infernal animal, down whose throat one is for ever pouring food compounded of coal and oxide of iron, which the beast digests amidst a hurricane of fire, and which it gives out down below in the form of fused metal, whilst the gases, the dust, the slag of every kind goes off elsewhere. ”

“ There was a period when the steel works were quite unable to cope with the demands for steel, yet the iron foundries were crying out for work. This question then arose in many minds, Why not make cast iron shells? The answer is that cast iron is too weak: it would blow into fragments too soon.
Just think what a shell is and what it has to do. It is a metal case filled with explosive. It is thrown from a gun and is intended to blow itself to pieces on arrival at its destination. It is that self-destruction [Pg 147] which carries destruction to all around as well. ”

“ The defendants also introduced experts as witnesses, whose testimony tended to prove that, as stated by one of them, 'the furnaces thus figured by Karsten are planned for withdrawing the reduced metal continuously, and as fast as possible, from the oxidizing action of the blast and the intensely heated part of the slag. So, the metal is made to flow constantly outward and upward through the open eye into the forehearth, which is made as high as the inner crucible; and, generally, the clean molten metal alone is passing through this bootom eye. ”

“ The metal sinks through the ignited fuel, forming, in the hearth, a spongy mass or ball, which is lifted out by the smelters at the end of each operation, and carried to the forge hammer. The earthy matters form a fusible glass or slag melt, and collect at the lowest point of the hearth, whence they are removed by opening a hole pierced through the front wall at the bottom. The active portion of such a furnace is essentially that above the blast-pipe, the function of the lower part being merely the collection of the reduced metal ”

“ In automatic fire-sprinklers the orifices of the pipes are closed with fusible metal, which melts and liberates the water when, owing to an outbreak of fire in the room, the temperature rises above a predetermined limit. ”

“ The terrific heat from the first nozzle caused the metal to glow under the torch as if in an open-hearth furnace. From the second nozzle issued a stream of oxygen under which the hot metal of the door was completely consumed. The force of the blast as the compressed oxygen and acetylene were expelled carried a fine spray of the disintegrated metal visibly before it. And yet it was not a big hole that it made—scarcely an eighth of an inch wide, but clear and sharp as if a buzz-saw were eating its way through a three-inch plank of white pine. ”

“ Fuses are intended to communicate fire to the powder with which shells, &c. are filled, so as to make them burst in the places to which they are thrown. They are composed, according to some, of one pound of gunpowder, and two or three ounces of charcoal, well mixed together; or of four pounds of gunpowder, two of saltpetre, and one of sulphur. It is to be remarked that the time a bomb, or grenade, will take to burn, after it has been thrown out of the mortar, or a howitz out of a howitzer, depends entirely upon the length and quality of the fuse. ”

“ When a neutron strikes the nucleus of uranium-235 (235U) or plutonium-239 (239Pu) , it may cause the nucleus to split into two roughly equal fragments, releasing neutrons and energy. This is the well-known process of neutron-induced fission, the method in which nuclear energy is produced in both reactors and bombs. [14] The most common uranium isotope, 238U, also breaks up by fission, but does so all by itself, without the need for any external neutrons. That process is spontaneous fission and it goes on at random, very much like radioactive decay. ”

“ In producing bar-iron from pigs, the latter are melted in a furnace similar to a smith's forge, with a sloping cavity ten or twelve inches below, where the blast-pipe is admitted. This hearth is filled with charcoal and dross, or scoria; and upon these is laid the metal and more coal. After the coal has become well ignited, the blast is applied. The iron soon begins to melt, and as it liquefies, it runs into the cavity or hearth below. Here, being out of the reach of the blast, it soon becomes solid. ”

“ The opening for the fused iron was within the smelting-house, and I could run the ore on to the sandy floor in channels made for that purpose, and thus procure my pig iron or Bessemer steel as the case might be. In this blast-furnace I left several channels to [155] be connected in some way with a blast of cold air, for without this blast I could not of course expect to smelt the ore. To improve the draught, and to have Nature help me all possible, I built the chimney or cone of the blast furnace at least twenty feet high, of bricks, tapering the same in a cone form from the base to the apex. ”

“ In the metamorphosed granite mountains of the main range the typical fissure veins, with well-defined and nearly perpendicular walls, are found often aggregated in great numbers, and universally mineralized to a profitable degree. In the trachytic and porphyric districts rich fissures also prevail, running very high in silver as a rule, while occasionally the precious metals are associated with such quantities of lead or copper ore that the base metals more than pay all cost of mining and treating the ore. ”

“ We shall take with us swords, shields, and fire-arms, for defence. Unless I mistake the nature of their metals, our steel will resist any weapon they can manufacture. But what explosives or what noxious gases they may have, all strange to us, it is impossible to conjecture. ”

“ Iron and steel are of no use now; the corrosive power of our atmosphere is so great, that the heaviest and strongest structure if made of these metals would soon be eaten away. The great war ships of the ancients and their great merchant fleets soon became useless by corrosion. ”

“ Most metallic minerals, and even metals, contain great quantities of combustible parts; zinc, antimony, iron, copper, &c. burn and produce a very brisk flame, as long as the combustion of these inflammable parts remains, after which, if the fire be continued, the calcination begins, during which there enters into them new parts of air and heat, which fixes, and cannot be disengaged but by presenting to them combustible matters, with which they have a greater affinity than with those of the mineral, with which they are only united by the effort of calcination. ”

“ Like everything else in the world of iron and steel, these blast-furnaces have undergone revolutionary improvements during the past quarter of a century. From being most dangerous and destructive structures causing frightful loss of life and producing only about one ton of iron a day for every man working about them, as formerly, they have now become relatively harmless monsters, capable of turning out six times that quantity of ore for each man employed. ”