When the nineteenth century dawned, men were making brick in the same way for the most part that they were fifty centuries before. It is recorded in the eleventh chapter of Genesis that when "the whole earth was of one language and one speech, it came to pass as they journeyed from the east that they found a plain in the land of Shinar; and they dwelt there, and they said to one another, Go to, let us make brick and burn them thoroughly, And they had brick for stone, and slime had they for mortar." Then commenced the building of Babel. Who taught the trade to the brick-makers of Shinar? The journey from the east continued, and with it went brick making to Greece and Rome, across the continent of Europe, across the English channel, until the brick work of CÆsar, stamped by the trade mark of his legions, was found on the banks of the Thames, and through the fields of Caerleon and York. Alfred the Great encouraged the trade, and the manufacture flourished finely under Henry VIII., Elizabeth and Charles I. As to Pottery:—Could we only know who among the peoples of the earth first discovered, used, or invented fire, we might know who were the first makers of baked earthenware. Doubtless the art of pottery arose before men learned to bake the plastic clay, in Alongside the rudest and earliest chipped stone implements have been found the hollow clay dish for holding fire, or food, or water. "As the fragment of a speech or song, a waking or a sleeping vision, the dream of a vanished hand, a draught of water from a familiar spring, the almost perished fragrance of a pressed flower call back the singer, the loved and lost, the loved and won, the home of childhood, or the parting hour, so in the same manner there linger in this crowning decade of the crowning century bits of ancient ingenuity which recall to a whole people the fragrance and beauty of its past." Prof. O. T. Mason. The same gifted writer, adds: "Who has not read, with almost breaking heart, the story of Palissy, the Huguenot potter? But what have our witnesses to say of that long line of humble creatures that conjured out of prophetic clay, without wheels or furnace, forms and decorations of imperishable beauty, which are now being copied in glorified material in the best factories of the world? In ceramic as well as textile art the first inventors were women. They quarried the clay, manipulated it, constructed and decorated the ware, burned it in a rude furnace and wore it out in a hundred uses." From the early dawn of human history to its present noonday civilisation the progress of man may be traced in his pottery. Before printing was an art, he It would be pleasant to trace the history of pottery from at least the time of Homer, who draws a metaphor from the potter seated before his wheel and twirling it with both hands, as he shapes the plastic clay upon it; to dwell upon the clay tablets and many-coloured vases, covered with Egyptian scenes and history; to re-excite wonder over the arts of China, in her porcelain, the production of its delicacy and bright colours wrapped in such mystery, and stagnant for so many ages, but revived and rejuvenated in Japan; to recall to mind the styles and composition of the Phoenician vases with mythological legends burned immortally therein; the splendid work of the Greek potteries; to lift the Samian enwreathed bowl, "filled with Samian wine"; to look upon the Roman pottery, statues and statuettes of Rome's earlier and better days; the celebrated Faience (enamelled pottery) at its home in Faenza, Italy, and from the hands of its master, Luca della Robia; to trace the history of the rare Italian majolica; to tread with light steps the bright tiles of the Saracens; to rehearse the story of Bernard Palissy, the father of the beautiful French enamelled ware; to bring to view the splendid old ware of Nuremberg, the raised white figures on the deep blue plaques of Florence, the honest Delft ware of Holland; and finally to relate the revolution in the production of pottery throughout all Europe caused by the discoveries and inventions of Wedgwood of England in the eighteenth century. All this would be interesting, but we must hasten on to the equally The application of machinery to the manufacture of brick began to receive attention during the latter part of the eighteenth century, after Watt had harnessed steam, and a few patents were issued in England and America at that time for such machinery of that character, but little was practically done. The operations in brickmaking, to the accomplishment of which by machines the inventors of the nineteenth century have devoted great talent, relate: First, to the preparation of the clay.—In ancient Egypt, in places where water abounded, it appears that the clay was lifted from the bottoms of ponds and lakes on the end of poles, was formed into bricks, then sun-dried, modernly called adobes. The clay for making these required a stiffening material. For this straw was used, mixed with the clay; and stubble was also used in the different courses. Hence the old metaphor of worthlessness of "bricks without straw," but of course in burning, and in modern processes of pressing unburnt bricks, straw is no longer used. Sand should abound in the clay in a certain proportion, or be mixed therewith, otherwise the clay, whether burned or unburned, will crumble. Stones, gravel and sticks must be removed, otherwise the contraction of the clay and expansion of the stones on burning, produce a weak and crumbling structure. Brick clay generally is coloured by the oxide of iron, and in proportion as this abounds the burned brick is of a lighter or a deeper red. It may be desired to add colouring matter or mix different forms Many ages ago the Chilians of South America hung two ponderous solid wood or stone wheels on an axis turned by a vertical shaft and operated by animal power; the wheels were made to run round on a deep basin in which ores, or stones, or grain were placed to be crushed. This Chilian mill, in principle, was adopted a century or so ago in Europe to the grinding of clay. The pug mill has assumed many different forms in this age; and separate preliminary mills, consisting of rollers of different forms for grinding, alone are often used before the mixing operation. In one modern form the pug mill consists of an inverted conical-shaped cylinder provided with a set of interior revolving blades arranged horizontally, and below this a spiral arrangement of blades on a vertical axis, by which the clay is thoroughly cut up and crushed against the surrounding walls of the mill, in the meantime softened with water or steam if desired, and mixed with sand if necessary, and when thus ground and tempered is finally pressed down through the lower opening of the cylinder and directly into suitable brick moulds beneath. Second.—The next operation is for moulding and pressing the brick. To take the place of that ancient In some the pug mill is arranged horizontally to feed out the clay in the form of a long horizontal slab, which is cut up into proper lengths to form the bricks. Some machines are in the form of a large horizontal revolving wheel, having the moulds arranged in its top face, each mould charged with clay as the wheel presents it under the discharging spout of the grinding mill, and then the clay is pressed by pistons or plungers worked by a rocking beam, and adapted to descend and fit into the mould at stated intervals; or the moulds, carried in a circular direction, may have movable bottom plates, which may be pressed upwards successively by pistons attached to them and raised by inclines on which they travel, forcing the clay against a large circular top plate, and in the last part of the movement carrying the pressed brick through an aperture to the top of the plate, where it is met by and carried away on an endless apron. In some machines two great wheels mesh together, one carrying the moulds in its face, and the other the presser plate plungers, working in the former, the bricks being finally forced out on to a moving belt by the action of cam followers, or by other means. In others the moulds are passed, each beneath a gravity-descending or cam-forced plunger, the clay being thus stamped by impact into form; or in other forms the clay in the moulds may be subjected to successive pressure from the cam-operated pistons arranged horizontally and on a line with the discharging belt. Third, the drying and burning of the brick.—The old methods were painfully slow and tedious. A long time was occupied in seasoning the clay, and then after the bricks were moulded, another long time was necessary to dry them, and a final lengthy period was employed to burn them in crude kilns. These old methods were too slow for modern wants. But they still are in vogue alongside of modern inventions, as in all ages the use of old arts and implements have continued along by the side of later inventions and discoveries. No useful contrivances are suddenly or apparently ever entirely supplanted. The implements of the stone age are still found in use by some whose environment has deprived them of the knowledge of or desire to use better tools. The single ox pulling the crooked stick plough, or other similar ancient earth stirrer, and Ruth with her sickle and sheaves, may be found not far from the steam plough and the automatic binder. But the use of antiquated machinery is not followed by those who lead the procession in this industrial age. Consequently other means than the slow processes of nature to dry brick and other ceramics, and the crude kilns are giving way to modern heat distributing structures. Air and heat are driven by fans through chambers, in which the brick are openly piled on cars, the surplus heat and steam from an engine-room being often used for this purpose, and the cars so laden are slowly pushed on the tracks through heated chambers. Passages and pipes and chimneys for heat and air controlled by valves are provided, and the waste moisture drawn off through bottom drains or up chimneys, the draft of which is increased by a hot blast, or blasts Dr. Hoffmann of Berlin invented different forms of drying and burning chambers which attracted great attention. In his kiln the bricks are stacked in an annular chamber, and the fire made to progress from one section of the chamber to another, burning the brick as the heat advances; and as fast as one section of green brick is dried, or burned, it is withdrawn, and a green section presented. Austria introduced most successful and thorough systems of drying brick about 1870. In some great kilns fires are never allowed to cease. One kiln had been kept thus heated for fifteen years. Thus great quantities of green brick can at any time be pushed into the kiln on tracks, and when burned pushed out, and thus the process may go on continuously day and night. To return to pottery: As before stated, Wedgwood of England revolutionised the art of pottery in the eighteenth century. He was aided by Flaxman. Before their time all earthenware pottery was what is now called "soft pottery." That is, it was unglazed, simply baked clay; lustrous or semi-glazed and enamelled having a harder surface. Wedgwood invented the hard porcelain surface, and very many beautiful designs. To improve such earthenware and to best decorate it, are the objects around which modern inventions have mostly clustered. The "regenerative" principle of heating above referred to employed in some kilns, and so successfully The old method of burning wood, or soft coal, or charcoal at the bottom of a small old-fashioned cylindrical fire brick kiln attended to by hand, and heating the articles of pottery arranged on shelves in the chamber above, is done away with to a great extent in large manufactories for the making of stone and earthenware—although still followed in many porcelain kilns. Inventions in the line of pottery kilns have received the aid of woman. Susan Frackelton of the United States invented a portable kiln for firing pottery and porcelain, for which she obtained a patent in 1886. As in drying clay for brick, so in drying clay for porcelain and pottery generally, great improvements have been made in the drying of the clay, and other materials to be mixed therewith. A great step was taken to aid drying by the invention of the filter press, in which the materials, after they are mixed and while still wet, are subjected to such pressure that all surplus water is removed and all air squeezed out, by which the inclosure of air bubbles in the clay is prevented. Despairing of excelling the China porcelain, although Porcelain Moulding, and its accompanying ornamentation and the use of apparatus for moulding by compression and by exhaustion of the air has become since that time a great industry. Porcelain Colours.—Chemists also aided in discovering what metallic ingredients could best be used when mixed with the clay and sand to produce the desired colours. As soon as a new metal was discovered, it was tested to find, among other things, what vitrifiable colour it would produce. In the production of metallic glazes, the oxides generally are employed. The colours are usually applied to ware when it is in its unglazed or biscuit form. In the biscuit or bisque form pottery is bibulous, the prepared glaze sinks into its pores and when burned forms a vitreous coating. The application of oil colours and designs to ware before baking by the "bat" system of printing originated in the eighteenth and was perfected in the nineteenth century. It consists of impressing oil One manner for ages of applying colours to ware is first to reduce the mixture to a liquid form, called "slip," and then, if the Chinese method is followed, to dip the colour up on the end of a hollow bamboo rod, which end is covered with wire gauze, then by blowing through the rod the colour was sprayed or deposited on the ware. Another method is the use of a brush and comb. The brush being dipped into the coloured matter, the comb is passed over the brush in such manner as to cause the paint to spatter the object with fine drops or particles. A very recent method, by which the beautiful background and blended colours of the celebrated Rookwood pottery of Cincinnati, Ohio, have become distinguished, consists in laying the colour upon the ware in a cloud or sheet of almost imperceptible mist by the use of an air atomiser blown by the operator. By the use of this simple instrument, the laying on a single colour, or the delicate blending and shadings of two or more colours in very beautiful effects is easily produced. This use of the atomiser commenced in 1884, and was claimed as the invention of a lady, Miss Laura Fry, who obtained a patent for thus blowing the atomised spray colouring matter on pottery in 1889; but it was held by the courts that she was anticipated by experiments of others, and by descriptions in previous patents of the spraying of paint on other objects by compressed air apparatus known as the air brush. However, this introduction of the use of the atomiser caused quite a revolution in the art of applying colours to pottery in the forming of backgrounds. Enamelled ware is no longer confined to pottery. About 1878 Niedringhaus in the United States began to enamel sheet iron by the application of glaze and iron oxide, giving such articles a granite appearance; and since then metallic cooking vessels, bath tubs, etc., have been converted in appearance into the finest earthenware and porcelain, and far more durable, beautiful and useful than the plain metal alone for such purposes. When we remember that for many centuries, wood and pewter, and to some extent crude earthenware, were the materials from which the dishes of the great bulk of the human family were made, as well as their table and mantel ornaments, and compare them in character and plenteousness with the table and other ware of even the poorest character of to-day, we can appreciate how much has been done in this direction to help the human family by modern inventions. Artificial Stone.—The world as yet has not so far exhausted its supply of stone and marble as to compel a resort to artificial productions on a great scale, and yet to meet the demands of those localities wherein the natural supplies of good building stones and marble are very scarce, necessitating when used a long and expensive transportation, methods have been adopted by which, at comparatively small cost, fine imitations of the best stones and marbles have been produced, having all the durable and artistic qualities of the originals, as for the most part, they are composed of the same materials as the stone and marbles themselves. The characteristic backgrounds, the veins and shadowings, and the soft colours of various marbles have been quite successfully imitated by treating dehydrated One of the improvements in the manufacture and use of modern cements and artificial stones consists in their application to the making of streets and sidewalks. Neat, smooth, hard, beautiful pavements are now taking the place everywhere of the unsatisfactory gravel, wood, and brick pavements of former days. We know that the Romans and other ancient peoples had their hydraulic cements, and the plaster on some of their walls stands to-day to attest its good quality. Modern inventors have turned their attention in recent years to the production of machines to grind, crush, mix and set the materials, and to apply them to large wall surfaces, in place of hand labour. Ready-made plaster of a fine quality is now manufactured in great quantities. It needs only the addition of a little water to reduce it to a condition for use; and a machine operated by compressed air may be had for spreading it quickly over the lath work of wood or sheet metal, slats, or over rough cement ceilings and walls. Glass.—The Sister of Pottery is Glass. It may have been an accidental discovery, occurring when men made fire upon a sandy knoll or beach, that fire could melt and fuse sand and ashes, or sand and lime, or sand and soda or some other alkali, and with which may also have been mixed some particles of iron, or lead, or manganese, or alumina to produce that hard, lustrous, vitreous, brittle article that we call glass. But who invented the method of blowing the viscid Yet with the knowledge of making glass of the finest description existing for centuries, it is strange that its manufacture was not extended to supply the wants of mankind, to which its use now seems so indispensable. And yet as late as the sixteenth and seventeenth centuries glass windows were found only in the houses of the wealthy, in the churches and palaces, and glass mirrors were unknown except to the rich, as curiosities, and as aids to the scientists in the early days of telescopy. Poor people used oiled paper, isinglass, thinly shaved leather, resembling parchment, and thin sheets of soft pale crystalised stone known as talc, and soapstone. The nineteenth century has been characterised as the scientific century of glass, and the term commercial, may well be added to that designation. Its commercial importance and the advancement in its manufacture during the first half of the century is illustrated in the fact that the Crystal Palace of the London Industrial Exhibition of 1851, although containing nearly 900,000 square feet of glass, was furnished by a single firm, Messrs. Chance & Co. of London, without materially delaying their The principal improvements in the art of glass-making effected during the nineteenth century may be summarised as follows: First, Materials.—By the investigations of chemists and practical trials it was learned what particular effect was produced by the old ingredients employed, and it was found that the colours and qualities of glass, such as clearness, strength, tenacity, purity, etc., could be greatly modified and improved by the addition to the sand of certain new ingredients. By analysis it was learned what different metallic oxides should be employed to produce different colours. This knowledge before was either preserved in secrecy, or accidentally or empirically practised, or unknown. Thus it was learned and established that lime hardens the glass and adds to its lustre; that the use of ordinary ingredients, the silicates of lime, magnesia, iron, soda and potash, in their impure form, will produce the coarser kinds of glass, such as that of which green bottles are made; that silicates of soda and lime give the common window glass and French plate; that the beautiful varieties of Bohemian glass are chiefly a silicate of potash and lime; that crystal or flint glass, so called because formerly pulverised flints were used in making it, can be made of a suitable combination of potassia plumbic silicate; that the plumbic oxide greatly increases its transparency, brilliancy, and refractive power; that paste—that form of glass from which imitations of diamonds are cut, may be produced by adding a large proportion of the oxide Professor Faraday as early as 1824 had noticed a change in colour gradually produced in glass containing oxide of manganese by exposure to the rays of the sun. This observation induced an American gentleman, Mr. Thomas Gaffield, a merchant of Boston, to further experiment in this direction. His experiments commenced in 1863, and he subjected eighty different kinds of glass, coloured and uncoloured, and manufactured in many different countries, to this exposure of the sun's rays. He found that not only glass having manganese as an element, but nearly every species of glass, was so affected, some in shorter and some in longer times; that this discoloration was not due to the heat rays of the sun, but to its actinic rays; and that the original colour of the glass could be reproduced by reheating the same. Mr. Gaffield also extended his experiments to ascertain the power of different coloured glasses to transmit the actinic or chemical rays, and found that blue would transmit the most and red and orange the least. Others proceeded on lines of investigation in ascertaining the best materials to be employed in glass-making in producing the clearest and most permanent uncoloured light; the best coloured lights for desired purposes; glasses having the best effects on the growth of plants; and the best class for refracting, Another illustration of modern scientific investigation and success in glass-making materials is seen at the celebrated German glass works at Jena under the management of Professors Ernst Abbe and Dr. Schott, commenced in 1881. They, too, found that many substances had each its own peculiar effect in the refraction and dispersion of light, and introduced no fewer than twenty-eight new substances in glass making. Their special work was the production of glass for the finest scientific and optical purposes, and the highest grades of commercial glass. They have originated over one hundred new kinds of glass. Their lenses for telescopes and microscopes and photographic cameras, and glass and prisms, and for all chemical and other scientific work, have a worldwide reputation. So that in materials of composition the old days in which there were substantially but two varieties of glass—the old-fashioned standard crown, and flint glass—have passed away. Methods.—The revolution in the production of glass has been greatly aided also by new methods of treatment of the old as well as the new materials. For instance, the application of the Siemens regenerative furnace, already alluded to in referring to pottery, in place of old-fashioned kilns, and by which the amount of smoke is greatly diminished, fuel saved, and the colour of the glass improved. Pots are used containing the materials to be melted and not heated in the presence of the burning fuel, but by the heated gases in separate compartments. Another process is that of M. de la Bastie, added Another process is that of making plate glass by the cylinder process—rolling it into large sheets. Other processes are those for producing hollow ware by pressing in moulds; for decorating; for surface enamelling of sheet glass whereby beautiful lace patterns are transferred from the woven or netted fabric itself by using it as a stencil to distribute upon the surface the pulverised enamel, which is afterwards burned on; of producing iridescent glass in which is exhibited the lights and shadows of delicate soap bubble colours by the throwing against the surface of hydrochloric acid under pressure, or the fumes of other materials volatilised in a reheating furnace. Then there is Dode's process for platinising glass, by which a reflecting mirror is produced without silvering or otherwise coating its back, by first applying a thin coating of platinic choride mixed with an oil to the surface of the glass and heating the same, by which the mirror reflects from its front face. The platinum film is so thin that the pencil and hand of a draughtsman may be seen through it, the object to be copied being seen by reflection. Again there is the process of making glass wool or silk—which is glass drawn out into such extremely fine threads that it may be used for all purposes of silk threads in the making of fabrics for decorative purposes and in some more useful purposes, such as the filtration of water and other liquids. We have already had occasion to refer to Tilghman's sand blast in describing pneumatic apparatus. In glass manufacture the process is used in etching on glass designs of every kind, both simple and intricate. The sand forced by steam, or by compressed air on the exposed portions of the glass on which the design rests, will cut the same deeply, or most delicately, as the hand and eye of the operator may direct. Machines.—In addition to the new styles of furnaces, moulds and melting, and rolling mills to which we have alluded, mention may be made of annealing and cooling ovens, by which latter the glass is greatly improved by being allowed to gradually cool. A large number of instruments have been invented for special purposes, such as for making the beautiful expensive cut glass, which is flint glass ground by wheels of iron, stone, and emery into the desired designs, while water is being applied, and then polished by wheels of wood, and pumice, or rottenstone; for grinding and polishing glass for lenses; and for polishing and finishing plate glass; for applying glass lining to metal pipes, tubes, etc.; for the delicate engraving of glass by small revolving copper disks, varying in size from the diameter of a cent down to one-fifteenth of an inch, cutting the finest blade of grass, a tiny bud, the downy wing of an insect, or the faint shadow of an exquisite eyebrow. Cameo cutting and incrustation; porcelain electroplating and moulding apparatus, and apparatus for making porcelain plates before drying and burning, may be added to the list. It would be a much longer list to enumerate the various objects made of glass unknown or not in common Rubber—Goodyear.The rubber tree, whether in India with its immense trunk towering above all its fellows and wearing a lofty crown, hundreds of feet in circumference, of mixed green and yellow blossoms; or in South America, more slender and shorter but still beautiful in clustered leaves and flowers on its long, loosely pendent branches; or in Africa, still more slender and growing as a giant creeper upon the highest trees along the water courses, hiding its struggling support and festooning the whole forest with its glossy dark green leaves, sweetly scented, pure white, star-like flowers, and its orange-like fruit—yields from its veins a milk which man has converted into one of the most useful articles of the century. The modes of treating this milky juice varies among the natives of the several countries where the trees abound. In Africa they cut or strip the bark, and as the milk oozes out the natives catch and smear it thickly over their limbs and bodies, and when it dries pull it off and cut it into blocks for transportation. In Brazil the juice is collected in clay vessels and smoked and dried in a smouldering fire of palm nuts, which gives the material its dark brown appearance. They mould the softened rubber over clay patterns in the form of shoes, jars, vases, It was in 1736 that La Condamine described rubber to the French Academy. He afterward resided in the valley of the Amazon ten years, and then he and MM. Herissent, Macquer, and Grossat, again by their writings and experiments interested the scientific and commercial world in the matter. In 1770 Dr. Priestley published the fact that this rubber had become notable for rubbing out pencil marks, bits of it being sold for a high price for that purpose. About 1797, some Englishman began to make water-proof varnish from it, and to take out patents for the same. This was as far as the art had advanced in caoutchouc, or rubber, in the eighteenth century. In 1819 Mr. Mackintosh, of Glasgow, began experimenting with the oil of naphtha obtained from gas works as a solvent for India rubber; and so successfully that he made a water-proof varnish which was applied to fabrics, took out his patent in England in 1823, and thus was started the celebrated "Mackintoshes." In 1825 Thomas C. Wales, a merchant of Boston, conceived the idea of sending American boot and shoe lasts to Brazil for use in place of their clay models. This soon resulted in sending great quantities of rubber overshoes to Europe and America. The importation of rubber and the manufacture of water-proof garments and articles therefrom now rapidly increased in those countries. But nothing For fifty years, ever since the manufacturers and inventors of Europe and America had learned of the water-proof character of rubber, they had been striving to find something to overcome this difficulty. Finally it became the lot of one man to supply the want. His name was Charles Goodyear. Born with the century, in New Haven, Connecticut, and receiving but a public school education, he engaged with his father in the hardware business in Philadelphia. This proving a failure, he, in 1830, turned his attention to the improvement of rubber goods. He became almost a fanatic on the subject—going from place to place clad in rubber fabrics, talking about it to merchants, mechanics, scientists, chemists, anybody that would listen, making his experiments constantly; deeply in debt on account of his own and his father's business failures, thrown into jail for debt for months, continuing his experiments there with philosophical, good-natured persistence; out of jail steeped to his lips in poverty; his family suffering for the necessaries of life; selling the school books of his children for material to continue his work, and taking a patent in 1835 for a rubber cement, which did not help him much. Finding that nitric acid improved the quality of the rubber by removing its adhesiveness, he introduced this process, which met with great favour, was applied generally to the manufacture of overshoes, and helped his condition. But his trials and troubles continued. Finally one Nathaniel Haywood suggested the use of sulphurous acid gas, and this And now at this later day, when $50,000,000 worth of rubber goods are made annually in the United States alone, the whole immense business is still divided into but two classes—hard and soft—hard or vulcanized like that called "ebonite," or soft, it may be, as a delicate wafer. And these qualities depend on and vary as a greater or less amount of sulphur is used, as described in the patents of Goodyear, commencing with his French patent of 1844. Then of course the pirates began their attacks, and he was kept poor in defending his patents, and died comparatively so in 1860; but happy in his great discovery. He had received, however, the whole world's honours—the great council medal at the Nations Fair in London in 1851 the Cross of the Legion of Honour by Napoleon III., and lesser tributes from other nations. It can be imagined the riches that flowed into the laps of Goodyear's successors; the wide field opened for new inventions in machines and processes; and the vast added comforts to mankind resulting from But rubber and steel as we now know them are not the only new fabrics given to mankind by the inventors of the Nineteenth Century. The work of the silk worm has been rivalled; and a wool as white and soft as that clipped from the cleanest lamb has been drawn by the hands of these magicians from the hot and furious slag that bursts from a blast furnace. The silk referred to is made from a solution of that inflammable material of tremendous force known as gun-cotton, or pyroxylin. Dr. Chardonnet was the inventor of the leading form of the article, which he introduced and patented about 1888. The solution made is of a viscous character, allowed to escape from a vessel through small orifices in fine streams; and as the solvent part evaporates rapidly these fine streams become hard, flexible fibres, which glisten with a beautiful lustre and can be used as a substitute for some purposes for the fine threads spun by that mysterious master of his craft—the silk worm. The gusts of wind that drove against the molten lava thrown from the crater of Kilauea, producing as it did, a fall of white, metallic, hairy-like material resembling wool, suggested to man an industrial application of the same method. And at the great works of Krupp at Essen, Prussia, for instance, may be witnessed a fine stream of molten slag flowing from an iron furnace, and as it falls is met by a strong blast of cold air which transforms it into a silky mass as white and fine as cotton. |