Orthopaedics, like many specialties, has developed through a necessity. A necessity to correct deformity, restore function and alleviate pain. Orthopaedic surgeons have developed an ability to prevent major losses of bodily function and indeed they can prevent otherwise inevitable death. They seek perfection of their art, by ensuring that the patient reaches optimal condition in the shortest period of time by the safest possible method.
Salt is physiologically absolutely necessary for human life, but in the past prior to the Industrial Revolution the known mineral salt sources were limited so much so, that its supply was a critical demographic power factor for most communities, until industrial means of extraction from brines were devised. It was only available as visible and exposed rock outcrops in arid regions, or as dried out salt cake on the shores of some seas and salt lakes. In areas with wet climates, the protruding salt dissolved making it almost impossible to discover. It is probably this, more than for any other reason, that many of the great civilisations first developed near deserts and desert climates, for example the Mediterranean region, at the edges of the "arid" zones.
Much of the ancient history of fragrance is shrouded in mystery. Anthropologists speculate that primitive perfumery began with the burning of gums and resins for incense. Eventually, richly scented plants were incorporated into animal and vegetable oils to anoint the body for ceremony and pleasure. From 7000 to 4000 bc, the fatty oils of olive and sesame are thought to have been combined with fragrant plants to create the original Neolithic ointments. In 3000 bc, when the Egyptians were learning to write and make bricks, they were already importing large quantities of myrrh. The earliest items of commerce were most likely spices, gums and other fragrant plants, mostly reserved for religious purposes.
The Romans, in their wisdom, were the first people to use a structure to give plants protection.
They used heated pits covered with translucent slabs of rock to form primitive greenhouses.
It was, however in the days of the great explorers that the glasshouse (to give it its correct name) came into its own in the 17th and 18th centuries.
Strange exotic plants and seeds were being bought back to this country, from far distant lands.
The engraving is not a drawing transferred onto wood, metal or stone; it is conceived in consideration of the material which is used to make it, its nature, resources and potentialities; this is the essential starting point for achieving a style. Because it is on the matrix and not on the paper that the artist puts his creative stamp, which will be revealed in the finished print
According to the Corning Museum of Glass web site, glass making was discovered by potters in Mesopotamia, within the area now known as the countries of Iraq and Syria."As early as 3,300 years ago, secret "instructions" for furnace building and glassmaking in Mesopotamia were written on clay tablets in a cuneiform alphabet. These instructions were copied and recopied over the centuries." (From the Corning Museum site.) A glimpse of glass making in the 4th Century A.D. is provided by a huge glass slab found in Beth Shearim, Israel. See below for more information about the Corning Museum web site.
History of Concrete
Timeline
Ancient Egypt
Egyptians used calcinated gypsum to give brick or stone structures a smooth coating.
Ancient Greece
A similar application of calcinated limestone was used by the ancient Greeks.
Ancient Rome
The Romans frequently used broken brick aggregate embedded in a mixture of lime putty with brick dust or volcanic ash. They built a wide variety of structures that incorporated stone and concrete, including roads, aquaducts, temples and palaces.
The carousel originated in Europe, but reached its greatest fame in America in the 1900's. The first carousels featured gondolas, carts, menagerie animals, and horses. The French developed many variations of the carousel. In one variation, the riders tried to spear gold rings with lances while the carousel rotated at full speed. This undoubtedly led to the phrase, "catching the brass ring" on later carousels.
500 B.C. The abacus was first used by the Babylonians as an aid to simple arithmetic at sometime around this date. The abacus in the form we are most familiar with was first used in China in around 1300 A.D.
1623 Wilhelm Schickard (1592-1635), of Tuebingen, Wuerttemberg (now in Germany), made a "Calculating Clock". This mechanical machine was capable of adding and subtracting up to 6 digit numbers, and warned of an overflow by ringing a bell. Operations were carried out by wheels, and a complete revolution of the units wheel incremented the tens wheel in much the same way counters on old cassette deck worked.
The main function of all castles was defense, everything else was secondary. They were always surrounded by a curtain wall, which was often supplemented by a reinforced shield wall at strategic points. Crenellated battlements and arrow slits protected the defenders, and attackers often also had to overcome a series of several gates. The main entrance was protected by a drawbridge and machicolations projecting over the gate, from which boiling liquids and missiles could be dropped on the hapless foes below. The final refuge of the castle residents was the stronghold, or keep. It was the tallest and strongest building within the walls, with a high entrance accessible only via a removable ladder or wooden bridge. In addition to being a watchtower and the centre point of the entire castle, the keep was also a status symbol. The main residential building (great hall) was called the Palas. The castle chapel was often installed in the gatehouse or one of the main towers (nearer my God to Thee!), and a small garden inside the walls provided herbs, flowers and vegetables in emergencies. Offices and service rooms were generally located in the outer ward.
