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The writing was in the form of a series of wedge-shaped signs pressed into soft clay by means of a reed stylus to create simple pictures, or pictograms, each representing an object. the script progressively evolved to encompass more abstract concepts as well as phonetic functions (representing sounds, just like the modern Western alphabet) enabling the recording of messages and ideas.
The clay subsequently hardened in the Sun or was baked to form permanent tablets. For the first time news and ideas could be carried to distant places without having to rely on a messenger's memory and integrity.
They did not have the benefit of cheap, off the shelf, mass produced batteries. Bronze is a relatively hard alloy of copper and tin, better suited for the purpose than the much softer copper enabling improved durability of the weapons and the ability to hold a cutting edge.
For many years the telegraph, and later the telephone, industries were the only consumers of batteries in modest volumes and it wasn't until the twentieth century that new applications created the demand that made the battery a commodity item. The use of bronze for tools and weapons gradually spread to the rest of the World until it was eventually superceded by the much harder iron.
The electronics, computers and communications industries, power engineering and much of the chemical industry of today were founded on discoveries made possible by the battery.
Pioneers It is often overlooked that throughout the nineteenth century, most of the electrical experimenters, inventors and engineers who made these advances possible had to make their own batteries before they could start their investigations. the World was starting to emerge from the Stone Age. C., Mesopotamians (from modern day Iraq), who had already been active for hundreds of years in primitive metallurgy extracting metals such as copper from their ores, led the way into the Bronze Age when artisans in the cities of Ur and Babylon discovered the properties of bronze and began to use it in place of copper in the production of tools, weapons and armour.
In recent years batteries have changed out of all recognition. Today the cells are components in battery systems, incorporating electronics and software, power management and control systems, monitoring and protection circuits, communications interfaces and thermal management. Mesopotamia, incorporating Sumer, Babylonia and Assyria, known in the West as the Cradle of Civilisation was located between the Tigris and Euphrates rivers (The name means "land between the rivers") in the so called Fertile Crescent stretching from the current Gulf of Iran up to modern day Turkey. the Sumerians of ancient Mesopotamia developed the World's first written language.
(See Map of Mesopotamia) Unfortunately this accolade ignores the contributions of the Chinese people and the Harappans of the Indus Valley, (Modern day Pakistan) who were equally "civilised" during this period practicing metallurgy (copper, bronze, lead, and tin) and urban planning, with civic buildings, baked brick houses, and water supply and drainage systems. Called Cuneiform Writing from the Latin "cuneus", meaning "wedge", it was developed as a vehicle for commercial accounting transactions and record keeping.
In this way he was able to calculate the distance to far off objects without measuring the distance directly, the basis of modern surveying.
Egypt was also home to Imhotep the first man of science in recorded history. both of which refer to earlier works attributed to Imhotep. The process for making wrought iron was discovered by the Hittites, in Northern Mesopotamia and Southern Anatolia (now part of Eastern Turkey), who heated iron ore in a charcoal fire and hammered the results into wrought (worked) iron. Recorded in the Bible, Book of Exodus, Chapter 39, Verse 3, - "And they did beat the gold into thin plates, and cut it into wires, to work it. Its construction is described in great detail in the book of Exodus and according to the Bible and Jewish legend it was endowed with miraculous powers including emitting sparks and fire and striking dead Aaron's sons and others who touched it.
He was the world's first named architect and administrator who around 2725 B. built the first pyramid ever constructed, the Stepped Pyramid of Saqqara. The first outlines surgical treatments for various wounds and diseases and the second contains 877 prescriptions and recipes for treating a variety of medical conditions making Imhotep the world's first recorded physician. The earliest evidence of the art of stencilling used by the Egyptians. in the fine linen, with cunning work." The Egyptians also made coarse glass fibres as early as 1600 B. and fibers survive as decorations on Egyptian pottery dating back to 1375 B. It was basically a wooden box of acacia wood lined with gold and also overlaid on the outside with gold.
Produced from the freshwater papyrus reed, the papyrus scrolls were fragile and susceptible to decay from both moisture and excessive dryness and many of them have thus been lost, whereas the older, more durable clay cuneiform tablets from Mesopotamia have survived. Sumerian mathematics and science used a base 60 sexagesimal numeral system.
Historians seem to agree that the wheel and axle were invented around 3500 B. 60 is divisible by 1,2,3,4,5,6,10,12,15,20,30 and 60 making it more convenient than using a base 10 decimal system when working with fractions.
It seems Tesla's explanation was appropriately named. Also called magnetite, lodestone is a magnetic oxide of iron (Fe) which was mined in the province of Magnesia in Thessaly from where the magnet gets its name.