Inventions in the Century Part 31

In America in 1806 David Melville of Newport, Rhode Island, lighted with gas his own house and the street in front of it. In 1813 he took out a patent and lighted several factories. In 1817 his process was applied to Beaver Tail Lighthouse on the Atlantic coast--the first use of illuminating gas in lighthouses. Coal oil and electricity have since been found better illuminants for this purpose.

Murdoch, Winser, Clegg and others continued to illuminate the public works and buildings of England. Westminster Bridge and the Houses of Parliament were lighted in 1813, and the streets of London in 1815.

Paris was lighted in 1820, and the largest American cities from 1816 to 1825. But it required the work of the chemists as well as the mechanics to produce the best gas. The rod of Science had touched the rock again and from the earth had sprung another servant with power to serve mankind, and waited the skilled brain and hand to direct its course.

Produced almost entirely from bituminous coal, it was found to be composed chiefly of carbon, oxygen and hydrogen; but various other gases were mixed therewith. To determine the proper proportions of these gases, to know which should be increased or wholly or partly eliminated, required the careful labours of patient chemists. They taught also how the gas should be distilled, condensed, cleaned, scrubbed, confined in retorts, and its flow measured and controlled.

Fortunately the latter part of the eighteenth century and the early part of the nineteenth had produced chemists whose investigations and discoveries paved the way for success in this revolution in the world of light. Priestley had discovered oxygen. Dalton had divided matter into atoms, and shown that in its every form, whether solid, liquid, or gaseous, these atoms had their own independent, characteristic, unalterable weight, and that gases diffused themselves in certain proportions.

Berthollet, Graham, and a host of others in England, France, and Germany, advanced the art. The highest skilled mechanics, like Clegg of England, supplied the apparatus. He it was who invented a gas purifier, liquid gas meter, and other useful contrivances.

As the character of the gas as an illuminator depends on the quant.i.ty of hydro-carbon, or olefiant elements it contains, great efforts were made to invent processes and means of carbureting it.

The manufacture of gas was revolutionised by the invention of water gas.

The main principle of this process is the mixture of hydrogen with the vapour of some hydro-carbon: Hydrogen burns with very little light and the purpose of the hydro-carbon is to increase the brilliancy of the flame. The hydrogen gas is so obtained by the decomposition of water, effected by pa.s.sing steam through highly heated coals.

Patents began to be taken out in this line in England in 1823-24; by Donovan in 1830; Geo. Lowe in 1832, and White in 1847. But in England water gas could not compete with coal gas in cheapness. On the contrary, in America, especially after the petroleum wells were opened up, and nature supplied the hydro-carbon in roaring wells and fountains, water gas came to the front.

The leading invention there in this line was that of T. S. C. Lowe of Morristown, Pennsylvania, in 1873. In Lowe's process anthracite coal might be used, which was raised in a suitable retort to a great heat, then superheated steam admitted over this hot bed and decomposed into hydrogen and carbonic oxide; then a small stream of naphtha or crude petroleum was thrown upon the surface of the burning coal, and from these decompositions and mixtures a rich olefiant product and other light-giving gases were produced.

The Franklin Inst.i.tute of Philadelphia in 1886 awarded Lowe, or his representatives, a grand medal of honour, his being the invention exhibited that year which in their opinion contributed most to the welfare of mankind.

A number of inventors have followed in the direction set by Lowe. The largest part of gas manufacture, which has become so extensive, embodies the basic idea of the Lowe process.

The compet.i.tion set up by the electricians, especially in the production of the beautiful incandescent light for indoor illumination, has spurred inventors of gas processes to renewed efforts--much to the benefit of that great mult.i.tude who sit in darkness until corporations furnish them with light.

It was found by Siemens, the great German inventor of modern gas regenerative furnace systems, that the quality of the gas was much improved, and a greater intensity of light obtained, by heating the gases and air before combustion--a plan particularly adapted in lighting large s.p.a.ces.

To describe in detail the large number of inventions relating to the manufacture of gas would require a huge volume--the generators, carburetors, retorts, mixers, purifiers, metres, scrubbers, holders, condensers, governors, indicators, registers, chargers, pressure regulators, etc., etc.

It was a great convenience outside of towns and cities, where gas mains could not be laid, to have domestic plants and portable gas apparatus, worked on the same principles, but in miniature form, adapted to a single house, but the exercise of great ingenuity was required to render such adaptation successful.

In the use of liquid illuminants, which need a wick to feed them, the _Argand burner_--that arrangement of concentric tubes between which the wick is confined--although invented by Argand in 1784, yet has occupied a vast field of usefulness in connection with the lamps of the nineteenth century.

A dangerous but very extensively used illuminating liquid before coal oil was discovered was camphene, distilled from turpentine. It gave a good light but was not a safe domestic companion.

Great attention has recently been paid to the production of _acetylene_ gas, produced by the reaction between _calcium carbide_ and water. The making of the calcium carbide by the decomposition of mixed pulverised lime and coal by the use of a powerful electric battery, is a preliminary step in the production of this gas, and was a subsequent discovery.

The electric light, acetylene, magnesium, and other modern sources of light, although they may be more brilliant and intense than coal gas, cannot compete in cheapness of production with the latter. Thus far illuminating coal gas is still the queen of artificial lights.

After gas was fairly started in lighting streets and buildings its adaptation to lamps followed; and among the most noted of gas lamps is that of Von Welsbach, who combined a bunsen gas flame and a gla.s.s chimney with a "_mantle_" located therein. This mantle is a gauze-like structure made of refractory quartz, or of certain oxides, which when heated by the gas flame produce an incandescent glow of intense brilliancy, with a reduced consumption of gas.

CHAPTER x.x.xI.

BRICK, POTTERY, GLa.s.s, PLASTICS.

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 pa.s.s as they journeyed from the east that they found a plain in the land of s.h.i.+nar; 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 s.h.i.+nar?

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 Caesar, 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 that groping time when men, kneading the soft clay with their fingers, or imprinting their footsteps in the yielding surface and learning that the sun's heat stiffened and dried those forms into durability, applied the discovery to the making of crude vessels, as children unto this day make dishes from the tenacious mud. But the artificial burning of the vessels was no doubt a later imitation of Nature.

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 inscribed on it his literature. Poets and painters have adorned it; and in its manufacture have been embodied through all ages the choicest discoveries of the chemist, the inventor and the mechanic.

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 j.a.pan; to recall to mind the styles and composition of the Ph[oe]nician 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 rehea.r.s.e 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 splendid and more practical works of the busy nineteenth century, in which many toilsome methods of the past have been superseded by labour-saving contrivances.

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 of clay, or add sand or other ingredients. Clay treated by hand was for ages kneaded as dough is kneaded, by the hand or feet, and the clay was often long subjected, sometimes for years, to exposure to the air, frost and sun to disintegrate and ripen it. As the clay must be first disintegrated, ground or pulverised, as grain is first ground to flour to make and mould the bread, so the use of a grinding mill was long ago suggested.

The first machine used to do all this work goes by the humble name of _pug mill_.

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 a.s.sumed 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 and still used mode of filling a mould of a certain size by the hands with a lump of soft clay, sc.r.a.ping off the surplus, and then dumping the mould upon a drying floor, a great variety of machines have been invented.

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 ap.r.o.n.

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 pa.s.sed, 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. Pa.s.sages 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 of heated air are driven in one direction through a chamber while the brick are moved through in the opposite direction, or a series of drying chambers are separated from each other by iron folding-doors, the temperature increasing as cars are moved on tracks from one chamber to another.

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 quant.i.ties 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; _l.u.s.trous_ 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 cl.u.s.tered.

The "_regenerative_" principle of heating above referred to employed in some kilns, and so successfully incorporated in the regenerators invented since 1850 by Siemens, Frank, Boetius, b.i.+.c.heroux, Pousard and others, consisting in using the intensely hot wasted gases from laboratories or combustion chambers to heat the incoming air, and carrying the mingled products of combustion into chambers and pa.s.sages to heat, dry or burn materials placed therein, has been of great service in the production of modern pottery; not only in a great saving in the amount of fuel, but in reduction in loss of pieces of ware spoiled in the firing.