Anaxagoras was an Ionian philosopher. He was born in 488 BC at Clazomense and died in 428 BC. When only about twenty years of age he settled at Athens, and soon gained a high reputation, and gathered round him a circle of renowned pupils, including Pericles, Euripides, Socrates, etc. At the age of fifty he was publicly charged with impiety and condemned to death, but the sentence was commuted to perpetual banishment. Thereupon he went to Lampsacus, where he died. Anaxagoras belonged to the atomic school of Ionic philosophers. He held that there was an infinite number of different kinds of elementary atoms, and that these, in themselves motionless and originally existing in a state of chaos, were put in motion by an eternal, immaterial, spiritual, elementary being, Nous (Intelligence), from which motion the world was produced. The stars were, according to him, of earthy materials; the sun a glowing mass, about as large as the Peloponnesus;
the earth was flat; the moon a dark, inhabitable body, receiving its light from the sun; the comets wandering stars. Research Anaxagoras
Heraclitus was a Greek philosopher. He was born at Ephesus and lived about 513 BC. He travelled in different countries, particularly in Africa. On his return to Ephesus he was offered the chief magistracy, but refused it. He is said to have latterly repaired to solitary mountains to live on roots and herbs; but, being attacked by a fatal disease, was obliged to return to the city, where he died soon afterwards, it is said in his sixtieth year.
He left a work on Nature, in which he treats also of religion and politics. Some fragments only of this work remain. He is considered as belonging generally to the Ionic school of philosophers, though he differed from it in important particulars. He considered fire as the first principle of all things, describing it as an ethereal substance, 'self-kindled and self-extinguished,' from which the world is evolved (not made) by a natural operation. It is also a rational principle, and the source of the human soul. Phenomena exist in a constant state of flux, always tending to assume new forms, and finally returning again to their source. Research Heraclitus
Herodotus was a Greek historian. He was born in 484 BC at Halicarnassus in Asia Minor and died in 420 BC. Before writing his history he travelled extensively, visiting the shores of the Hellespont and the Euxine, Scythia, Syria, Palestine, Babylon and Ecbatana, Egypt as far as Elephantine and other parts of northern Africa, everywhere investigating the manners, customs, and religion of the people, the history of the country, productions of the soil, etc.
On returning home he found that Lygdamis had usurped the supreme authority in Halicarnassus, and put to death the noblest citizens, among others his uncle, the epic poet Panyasis, and Herodotus was forced to seek an asylum in the island of Samos. Having formed a conspiracy with several exiles he returned to Halicarnassus and drove out the usurper, but the nobles who had acted with him immediately formed an aristocracy more oppressive than the government of the banished tyrant, and Herodotus withdrew to the recently founded colony of Thurii, in Italy, where he seems to have spent most of his remaining life.
Here, at an advanced age, we are told by Pliny, he wrote his immortal work, a statement strengthened by the fact that events are noticed in the body of the book which occurred so late as 409 BC, while its abrupt ending proves almost beyond question that he was prevented by death from completing it. The history is divided into nine books, each bearing the name of a muse, and is written in the Ionicdialect. The object of the historian is to narrate the conflict between the Greeks and Persians, and he traces the enmity of the two races back to mythical times. Rapidly passing over the mythical period he comes to Croesus, king of Lydia, of whom and of his kingdom he gives a comparatively full history.
The conquest of Lydia by Cyrus induces him to relate the rise of the Persian monarchy and the subjugation of Asia Minor and Babylon. The history of Cambyses and his Egyptian expedition leads him to introduce the valuable details of the history, geography, and manners and customs of Egypt, which occupy the second book.
The Scythian expedition of Darius causes the historian to treat of the Scythians and the north of Europe; and the subsequent extension of the Persian kingdom affords him the opportunity for giving an account of Gyrene and Libya. In the meantime the revolt of the Ionians breaks out, which eventually brings on the conflict between Greece and Persia. An account of this outbreak and of the rise of Athens after the expulsion of the Peisistratidae, is followed by what properly constitutes the principal part of the work, and the history of the Persian War now runs on in an uninterrupted stream until the taking of Sestos. Research Herodotus
Acrylamide is an odourless, free-flowing white crystalline used as a chemical intermediate in the production and synthesis of polyacrylamides. These high-molecular weight polymers can be modified to develop non-ionic, anionic, or cationic properties for specific uses. The principle end use of
acrylamide is in water-soluble polymers used as additives for water treatment, enhanced oil recovery, flocculants, papermaking aids, thickeners, soil conditioning agents, sewage and waste treatment, ore processing, and permanent press fabrics.
Acrylamide is also used in the synthesis of dyes, in copolymers for contact lenses, and the construction of damfoundations, tunnels, and sewers. The largest use for polyacrylamide is in treating municipal drinking water and wastewater. The polymer is also used to remove suspended solids from industrial wastewater before discharge, reuse, or disposal.
Acrylamides also find use in oil-drilling processes to control fluid losses. In the pulp and paper industry, polyacrylamides are used as binders and retention aids for fibres and to retain pigments on paper fibres.
Acrylamide is a soil stabiliser and also finds use in foundry operations to facilitate free sand flow into moulds. Home appliances, building materials, and automotive parts are coated with acrylamide resins and thermosetting acrylics. Acrylamides are formulated in cosmetics and soap preparations as thickeners and in dental fixtures, hair grooming preparations, and pre-shave lotions. Minor uses of acrylamide are as latex thickeners, emulsion stabilisers for printing inks, gelling agents for explosives, binders in adhesives and adhesive tape, in the production of diazo compounds, and for gel chromatography and electrophoresis.
Acrylamide occurs in crystalline form and in aqueous solution. It is soluble in water, methanol, ethanol, dimethyl ether, and acetone; it is insoluble in benzene and heptane. The monomer readily polymerises at the melting point or under ultraviolet light. Solid acrylamide is stable at room temperature, but may polymerise violently when melted or in contact with oxidising agents such as chlorine dioxide and bromine. When heated to decomposition, acrylamide emits a poisonous gas, acrid fumes, and NOx. If heating to high temperatures, acrylamide can explode. Acrylamide is also known as
acrylamide monomer, acrylic amide, propenamide, and 2-propenamide. Research Acrylamide
Lauramide DEA is a white, waxy, non-ionic, artificial chemical used in shampoos, bubble baths and detergents as a surfactant and foam-builder. Research Lauramide DEA
Zinc chloride (formerly known as butter of zinc) is a white crystalline compound with the formula ZnCl2. The anhydroussalt, which is deliquescent, can be made by the action of hydrogen chloride gas on hot zinc. It has a relatively low melting point and sublimes easily, indicating that it is a molecular compound rather than ionic. Various hydrates also exist. Zinc chloride is used as a catalyst, dehydrating agent, a wood preservative for discouraging fungoid growths and as a flux for hard solder. Research Zinc Chloride
Sulphides refers to a mineral group where sulphur is combined with one or more metals. The sulphides form an important class of minerals that includes the majority of the ore minerals. With them are classed the similar but rarer sulpharsenides, arsenides, and tellurides. Most of the sulphide minerals are opaque with distinctive colours and characteristically coloured streaks. Those that are non-opaque, such as cinnabar, realgar, and orpiment, have high refractive indices and transmit light only on thin edges.
The general formula for the sulphides is given as XmZn, in which X represents the metallic elements and Z the non-metallic element. The general order of listing of the various minerals is in a decreasing ratio of X:Z. The sulphides can be divided into small groups of similar structures but it is difficult to make broad generalizations about their structure. Regular octahedral or tetrahedral coordination about sulphur is found in many simple sulphides such as in galena, PbS, (with an NaCI type structure), and in sphalerite, Zns. In more complex sulphides, as well as sulphosalts, distorted coordination polyhedra may be found. Many of the sulphides have ionic and covalent bonding, whereas others, displaying most of the properties of metals, have metallic bonding characteristics. Research Sulphides
Ephesus was an ancient Greek city of Lydia, in Asia Minor, one of the twelve Ionian cities, on the south side of the Caystrus, near its mouth. It was at one time the grand emporium of Western Asia, having a convenient and spacious harbour. The apostle Paul visited Ephesus and established a Christian church there, to which he dedicated one of his epistles. It was famous for its temple of Artemis (Diana), called Artemision, the largest and most perfect model of Ionicarchitecture, and reckoned one of the seven wonders of the world. The first great temple, begun about 650 BC and finished after 120 years, was burnt by the notorious Herostratus in order to perpetuate his name in 356 BC (the night of Alexander the Great's birth). A second and more magnificent was then erected, which was burned by the Goths in 262. Some interesting remains were discovered by excavation during the 19th century. Several church councils were held here, especially the third ecumenical council of 431, at which Nestorius was condemned.
Architecture is the art or science of designing and building structures (houses, bridges etc) for human use. The term is particularly applied to the design and construction of large structures for human use which incorporate both practicality, and aesthetics.
The Egyptians are the most ancient nation known to us among whom architecture had attained the character of a fine art. Other ancient peoples among whom it had made great progress were the Babylonians, whose most celebrated buildings were temples, palaces, and hanging-gardens; the Assyrians, whose capital, Nineveh, was rich in splendid buildings; the Phoenicians, whose cities, Sidon, Tyre, etc, were adorned with equal magnificence; and the Israelites, whose temple was a wonder of architecture. But comparatively few architectural monuments of these latter nations have remained until our day.
This is not the case with the architecture of Egypt, however, of which we possess ample remains in the shape of pyramids, temples, sepulchres, obelisks, etc. Egyptian chronology is far from certain, but the greatest of the architectural monuments of the country, the pyramids of Ghizeh, are at least as old as 2800 or 2700 BC. The Egyptian temples had walls of great thickness and sloping on the outside from bottom to top; the roofs were flat, and composed of blocks of stone reaching from one wall or column to another. The columns were numerous, close, and very stout, generally without bases, and exhibiting great variety in the designs of their capitals. The principle of the arch though known was not employed for architectural purposes. Statues of enormous size, sphinxes carved in stone, and on the walls sculptures incut-line of deities and animals, with innumerable hieroglyphics, are the decorative objects which belong to this style.
The earliest architectural remains of Greece are of unknown antiquity, and consist of massive walls built of huge blocks of stone. In historic times the Greeks developed an architecture of noble simplicity and dignity. This style is of modern origin compared with that of Egypt, and the earliest remains give indications that it was in part derived from the Egyptian. It is considered to have attained its greatest perfection in the age of Pericles, or about 460-430 BC. The great masters of this period were Phidias, Ictinus, Gallicrates, etc. All the extant buildings are more or less in ruins. The style is characterized by beauty, harmony, and simplicity in the highest degree. Distinctive of it are what are called the orders of architecture, by which term are understood certain modes of proportioning and decorating the column and its superimposed entablature. The Greeks had three orders, called respectively the Doric, Ionic, and Corinthian.
Greek buildings were abundantly adorned with sculptures, and painting was extensively used, the details of the structures being enriched by different colours or tints. Lowness of roofs and the absence of arches were distinctive features of Greek architecture, in which, as in that of Egypt, horizontality of line is another characteristic mark. The most remarkable public edifices of the Greeks were temples, of which the most famous is the Parthenon at Athens. Others exist in various parts of Greece as well as in Sicily, Southern Italy, Asia Minor, etc, where important Greek communities were early settled. Their theatres were semicircular on one side and square on the other, the semicircular part being usually excavated in the side of some convenient hill. This part, the auditorium, was filled with concentric seats, and might be capable of containing 20,000 spectators. A number exist in Greece, Sicily, and Asia Minor, and elsewhere. No remains of private houses exist in Greece, Sicily, and Asia Minor, and elsewhere. No remains of private houses are known to exist. By the end of the Peloponnesian War, about 400 BC. the best period of Greek architecture was over; a noble simplicity had given place to excess of ornament. After the death of Alexander the Great in 323 the decline was still more marked.
Among the Romans there was no original development of architecture as among the Greeks, though they early took the foremost place in the construction of such works as aqueducts and sewers, the arch being in early and extensive use among this people. As a fine art, however, Roman architecture had its origin in copies of the Greek models, all the Grecian orders being introduced into Rome, and variously modified. Their number, moreover, was augmented by the addition of two new orders: the Tuscan and the Composite. The Romans became acquainted with the architecture of the Greeks soon after 200 BC, but it was not until about two centuries later that the architecture of Rome attained (under Augustus) its greatest perfection.
Among the great works now erected were temples, aqueducts, amphitheatres, magnificentvillas, triumphal arches, monumental pillars, etc. The amphitheatre differed from the theatre in being a completely circular or rather elliptical building, filled on all sides with ascending seats for spectators and leaving only the central space, called the arena, for the combatants and public shows. The Coliseum is a stupendous structure of this kind. The thermae, or baths, were vast structures in which multitudes of people could bathe at once. Magnificent tombs were often built by the wealthy. Remains of private residences are numerous, and the excavations at Pompeii in particular have thrown great light on the internal arrangements of the Roman dwelling-house. Almost all the successors of Augustus embellished Rome more or less, erected splendid palaces and temples, and adorned, like Hadrian, even the conquered countries with them. But after the period of Hadrian (117-138 AD) Roman architecture is considered to have been on the decline. The refined and noble style of the Greeks was neglected, and there was an attempt to embellish the beautiful more and more. This decline was all the more rapid latterly from the disturbed state of the empire and the incursions of the barbarians.
In Constantinople (Istanbul), after its virtual separation from the Western Empire, arose a style of art and architecture which was practised by the Greek Church during the whole of the middle ages. This is called the Byzantine style. The church of St Sophia at Istanbul, built by Justinian (reigned
527-565), offers the most typical specimen of the style, of which the fundamental principle was an application of the Roman arch, the dome being the most striking feature of the building. In the most typical examples the dome or cupola rests on four pendentives. After the dismemberment of the Roman Empire the beautiful works of ancient architecture were almost entirely destroyed by the Goths, Vandals, and other barbarians in Italy, Greece, Asia, Spain, and Africa; or what was spared by them was ruined by the fanaticism of the Christians. A new style of architecture now arose, two forms of which, the Lombard and the Norman Romanesque, form important phases of art. The Lombard prevailed in North Italy and South Germany from the eighth or ninth to the thirteenth century (though the Lombard rule came to an end in 774); the Norman Romanesque flourished, especially in Normandy and England, from the eleventh to the middle of the thirteenth century. The semicircular arch is the most characteristic feature of this style. With the Lombard Romanesque were combined Byzantine features, and buildings in the pure Byzantine style were also erected in Italy, as the Church of St Mark at Venice.
The conquests of the Moors introduced a fresh style of architecture into Europe after the eighth century - the Moorish or Saracenic. This style accompanied the spread of Islam after its rise in Arabia in the seventh century. The edifices erected by the Moors and Saracens in Spain, Egypt, and Turkey are distinguished, among other things, by a peculiar form of the arch, which forms a curve constituting more than half of a circle or ellipse. A peculiar flowery decoration, called arabesque, is a common ornament of this style, of which the building called the Alhambra is perhaps the chief glory.
The Germans were unacquainted with architecture until the time of Charlemagne (or Charles the Great, 742 to 814). He introduced into Germany the Byzantine and Romanesque styles. Afterwards the Moorish or Arabian style had some influence upon that of the western nations, and thus originated the mixed style which maintained itself till the middle of the thirteenth century. Then began the modern Gothic style, which grew up in France, England, and Germany. Its striking characteristics are its pointed arches, its pinnacles and spires, its large buttresses, clustered pillars, vaulted roofs, profusion of ornament, and, on the whole, its lofty, bold character. Its most distinctive feature, as compared with the Greek or the Egyptian style, is the predominance in it of perpendicular or rising lines, producing forms that convey the idea of soaring or mounting upwards. Its greatest capabilities have been best displayed in ecclesiastical edifices.
Buildings may be classified architecturally by period and by style. The chief British architectural periods are:
Among the most notable styles of architecture are Art Deco, a style popular in the 1920's and 1930's characterised by geometrical shapes and stylised natural forms and symmetry; Art Nouveau, a style popular between the 1880s and early 1900's with sinuous natural forms; Arts and Crafts, a reactionary style which rebelled against industrialisation and encouraged manual skills and simplicity; Baroque; Classical which is based upon Greco-Roman styles; Gothic which originated in Europe and was popular between the late 12th century and early 16th century, characterised by pointed arches; Queen Anne which was based on the Baroque style but included the intricate use of brick and Victorian which while partially associated with a revival of Gothic style also incorporated Classical elements and made great use of cast iron, typified in many of Britain's older railway stations before they were torn down and replaced with Modern style structures during the late 20th century. Research Architecture
An attic base is a peculiar form of moulded base for a column or pilaster, described by Vitruvius, applied under the Roman Empire to the Ionic and Corinthian and Roman Doric orders, and imitated by the architects of the Renaissance. Research Attic Base
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Abbreviations
Research Anaxagoras
