An Encyclopedia of the History of Technology part 6. This one of a kind encyclopedia presents the entire field of technology from rudimentary agricultural tools to communication satellites in this first of its kind reference source. Following an introduction that discusses basic tools, devices, and mechanisms, the chapters are grouped into five parts that provide detailed information on materials, power and engineering, transportation, communication and calculation, and technology and society, revealing how different technologies have together evolved to produce enormous changes in the course of history | INTRODUCTION Figure 5 Charles Babbage s Difference Engine 1833. See Chapter 15. In 1606 Francesco della Porta demonstrated the suction caused by condensing steam and its power to draw up water. In 1643 Evangelista Torricelli demonstrated the vacuum in a mercury barometer. Otto von Guericke Mayor of Magdeburg in 1654 performed his most dramatic experiment in which two teams of eight horses were shown to be unable to pull apart two halves of a copper sphere from which the air had been exhausted by 32 BASIC TOOLS DEVICES AND MECHANISMS an air pump to leave a vacuum. Atmospheric pressure held them together. In 1648 Blaise Pascal showed that the weight of a column of air was less at the top of a 4000-foot 1220m mountain than at the bottom. In 1660 the Hon. Robert Boyle formulated the Gas Laws and demonstrated the maximum height that water could be drawn by a suction pump. Others took up the theme of producing a vacuum by the condensation of steam. In 1659 the Marquis of Worcester described experiments with boiling water in a gun barrel the steam forcing the water out of one or more receivers connected to it. It was recorded that Sir Samuel Morland Magister Mechanicorum to King Charles II had recently shown the King a new invention. for raising any quantity of water to any height by the help of fire alone . Denis Papin a Huguenot refugee from France worked for Robert Boyle and later in the early 1690s constructed a small atmospheric steam engine. It worked it is said but was only a model of no practical use outside the laboratory. Papin shied at the problems of building a large-scale reproduction such as could be used for mine pumping. He devoted himself from then on to trying to harness the power of steam without the use of a cylinder and piston. His attempts led to no success. In 1699 Captain Thomas Savery demonstrated to the Royal Society a vacuum pump with two receivers and valve gear to alternate them and later built full-sized machines. Unfortunately the maximum .
