Early Modern (15th-18th Century)

Despite its pioneering technology in 1779, as the first structural use of cast iron, no eye witness accounts are known which describe the Iron Bridge being erected. However, recent discoveries, research and experiments have shed new light on the mystery of exactly how it was built, challenging the assumptions of recent decades. In 1997 a small watercolour sketch by Elias Martin came to light in Stockholm. Although there are a wealth of early views of the Bridge by numerous artists, this is the only one which actually shows it under construction.

The use of coke as a fuel to smelt iron had been attempted in the second half of the 17th Century, but the first successful process was established by Abraham Darby around 1709 at his newly acquired ironworks in the Coalbrookdale, Shropshire. This was a major industrial breakthrough because it allowed the casting of much larger pieces than the old charcoal fuel process, which had been largely restricted to pots and kettles. Darby’s achievement in mastering the coke smelting process enabled this small valley in Shropshire to become the cradle of the world’s industrial revolution. The products of Darby’s ironworks were shipped down the River Severn by barge to Bristol and thence all over Britain and progressively outwards to Europe and the rest of the world.

The VL is the oldest catalog of the web, started by Tim Berners-Lee, the creator of html and the web itself. Unlike commercial catalogs, it is run by a loose confederation of volunteers, who compile pages of key links for particular areas in which they are expert; even though it isn't the biggest index of the web, the VL pages are widely recognised as being amongst the highest-quality guides to particular sections of the web.

Science & Society Picture Library represents the collections of the National Museum of Science & Industry, Science Museum, National Museum of Photography, Film & Television, National Railway Museum.

Bridging rivers, gorges, narrows, straits, and valleys always has played an important role in the history of human settlement. Since ancient times, bridges have been the most visible testimony of the noble craft of engineers. A bridge can be defined in many ways, but Andrea Palladio, the great 16th century Italian architect and engineer, hit on the essence of bridge building when he said "...bridges should befit the spirit of the community by exhibiting commodiousness, firmness, and delight." In more practical terms, he went on to explain that the way to avoid having the bridge carried away by the violence of water was to make the bridge without fixing any posts in the water. Since the beginning of time, the goal of bridge builders has been to create as wide a span as possible which is commodious, firm, and occasionally delightful. Spanning greater distances is a distinct measure of engineering prowess.

Although these achievements are fundamental to modern mathematics and physics, it is less well known that Newton himself placed great value on his private researches into theology and alchemy. Interest in the wealth of surviving manuscript material in these areas has increased dramatically in recent years, and the Newton Project was formed in 1998 to make all Newton's texts, both 'scientific' and 'non-scientific' (including those papers relevant to his three decades service at the Royal Mint), available to a broad readership in a form that is at once scholarly and accessible. The Project aims to create a printed edition of Newton's theological, alchemical and administrative writings and an electronic edition of all his writings, including his correspondence.

The two greatest misconceptions about medicine arise primarily from our modern attempts at interpreting the medical system of the Middle Ages. The first misconception is to see medicine in the Middle Ages as an unsophisticated system. Early scholars of medieval medicine found medieval doctors' theories ridiculous when compared to modern ones. Charles Singer, for example, found medieval medicine demonstrative of "the wilting mind of the Dark Ages." <1> Singer also believed that medieval medicine, specifically the Anglo-Saxon herbals, "lacked any rational element which might mark the beginnings of scientific advance."<2> But recently, historians like M.L. Cameron in Anglo-Saxon Medicineand John Riddle in Contraception and Abortion from the Ancient World to the Renaissance attempt to validate medieval medicine in light of modern medicine. By analyzing common herbals, both Cameron and Riddle have found a few recipes that have therapeutic merit.

This is a brief outline of the development of string theory, the details of which will eventually fill many large volumes written by many people directly and indirectly involved in this rich and fascinating story.

Before we continue describing the evolution of ways to mark the passage of time, perhaps we should broadly define what constitutes a clock. All clocks must have two basic components:

a regular, constant or repetitive process or action to mark off equal increments of time. Early examples of such processes included the movement of the sun across the sky, candles marked in increments, oil lamps with marked reservoirs, sand glasses (hourglasses), and in the Orient, knotted cords and small stone or metal mazes filled with incense that would burn at a certain pace. Modern clocks use a balance wheel, pendulum, vibrating crystal, or electromagnetic waves associated with the internal workings of atoms as their regulators.

a means of keeping track of the increments of time and displaying the result. Our ways of keeping track of the passage of time include the position of clock hands and digital time displays.

The history of timekeeping is the story of the search for ever more consistent actions or processes to regulate the rate of a clock.

This is the calendar FAQ. Its purpose is to give an overview of the Christian, Hebrew, Persian, and Islamic calendars in common use. It will provide a historical background for the Christian calendar, plus an overview of the French Revolutionary calendar, the Maya calendar, and the Chinese calendar.