Electricity

William Gilbert (1544–1603) published On the Magnet and Magnetic Bodies, and on the Great Magnet the Earth in 1600, which laid the foundations of a theory of magnetism and electricity.

Otto von Guericke's experiments on electrostatics, published 1672

Dr. William Gilbert, in De Magnete, invented the New Latin word electricus from ἤλεκτρον (elektron), the Greek word for “amber”. Gilbert undertook a number of careful electrical experiments, in the course of which he discovered that many substances other than amber, such as sulphur, wax, glass, etc.,[90] were capable of manifesting electrical properties. Gilbert also discovered that a heated body lost its electricity and that moisture prevented the electrification of all bodies, due to the now well-known fact that moisture impaired the insulation of such bodies. He also noticed that electrified substances attracted all other substances indiscriminately, whereas a magnet only attracted iron. The many discoveries of this nature earned for Gilbert the title of founder of the electrical science.[91] By investigating the forces on a light metallic needle, balanced on a point, he extended the list of electric bodies, and found also that many substances, including metals and natural magnets, showed no attractive forces when rubbed. He noticed that dry weather with north or east wind was the most favourable atmospheric condition for exhibiting electric phenomena—an observation liable to misconception until the difference between conductor and insulator was understood.

Robert Boyle also worked frequently at the new science of electricity, and added several substances to Gilbert's list of electrics. He left a detailed account of his researches under the title of Experiments on the Origin of Electricity. Boyle, in 1675, stated that electric attraction and repulsion can act across a vacuum. One of his important discoveries was that electrified bodies in a vacuum would attract light substances, this indicating that the electrical effect did not depend upon the air as a medium. He also added resin to the then known list of electrics.

This was followed in 1660 by Otto von Guericke, who invented an early electrostatic generator. By the end of the 17th Century, researchers had developed practical means of generating electricity by friction with an electrostatic generator, but the development of electrostatic machines did not begin in earnest until the 18th century, when they became fundamental instruments in the studies about the new science of electricity. The first usage of the word electricity is ascribed to Sir Thomas Browne in his 1646 work, Pseudodoxia Epidemica. In 1729 Stephen Gray (1666–1736) demonstrated that electricity could be “transmitted” through metal filaments. ====

The concept for this was pioneered by America's Joseph Henry - who invented the relay in the early 1830's and had shared the knowledge during a chance visit with English telegraph co-patentee Charles Wheatstone, who in turn provided the knowledge of the relay's function to his partner Wm. F. Cooke.

http://ethw.org/Edison%27s_Electric_Light_and_Power_System

At New York City’s Pearl Street station, where such a system was first installed, Edison’s team designed a huge dynamo—the largest ever built up till that time—which they nicknamed the “Jumbo,” and built six of them for the Pearl Street station. Each Jumbo weighed about 27 tons and had a 10-foot armature shaft and an output of 100 kilowatts. Each dynamo was driven by a steam engine, which received steam from boilers located in another part of the plant. The Pearl Street plant was designed to run up to 1,400 lamps (light bulbs inserted into fixtures) continuously, and served an area of about one square mile.

http://ethw.org/Pearl_Street_Station

With the opening of the Pearl Street station in lower Manhattan at 3 o'clock in the afternoon on 4 September 1882, Thomas Edison publicly presented a complete system of commercial electric lighting and power.

Although AC power was growing in usage, Pearl Street station operated successfully until a fire broke out on the morning of 2 January 1890. It destroyed all but one of the Jumbo dynamos. This remaining unit is preserved today at the Henry Ford Museum and Greenfield Village, and was designated a National Historic Mechanical Engineering landmark by the American Society of Mechanical Engineers in 1980.

The History of Electrification | http://www.edisontechcenter.org/HistElectPowTrans.html


==== Franklin did not, of course, invent electricity, but he discovered many things about it, previously not understood: http://www.ushistory.org/franklin/science/electricity.htm

Benjamin Franklin and Electricity http://www.americaslibrary.gov/aa/franklinb/aa_franklinb_electric_2.html

Franklin wrote up his thoughts on electricity in several letters to a fellow scientist who lived in London. This scientist and other scientists in London thought Franklin's letters contained valuable information, so in 1751 they published them in a little book, Experiments and Observations on Electricity.

One of the letters contained Franklin's plan for how to prove that electricity and lightning were the same.

Franklin Discovered Electricity with Kite

According to MythBusters: Benjamin Franklin probably didn't fly his famous kite

http://www.discovery.com/tv-shows/mythbusters/mythbusters-database/ben-franklin-electricity/

Benjamin Franklin's Electric Motor http://ethw.org/Benjamin_Franklin%27s_Electric_Motor



http://ethw.org/Michael_Faraday

Faraday discovered, among other things, the laws of electrolysis, electromagnetic induction (1831), hydroelectricity (1843), the relationship between electricity and gravity (1851), and atmospheric magnetism (1851).

http://ethw.org/Nikola_Tesla

TESLA POLYPHASE SYSTEM is unveiled to the world at Chicago's Columbian Exposition, 1893. http://ethw.org/File:TeslaPOLYPHASEColumbianEXPO1893rwLIPACKownerA.jpg

Early Applications of Electricity

http://ethw.org/Early_Applications_of_Electricity

One of the first to think about using electricity for practical purposes was the American Joseph Henry. In 1829 he used a large battery to build a powerful electromagnet. It was not just a scientific instrument—it could do heavy work, such as lifting hundreds of pounds of metal. With his demonstration, Henry really began to transform electricity into something that people could use every day.

In 1834 Thomas Davenport designed a motor that was strong enough to run a small printing press. He patented the motor in 1837.

http://ethw.org/Leyden_jar

The Leyden jar was the first device capable of storing an electric charge. It was invented on 4 November 1745 by German experimenter Ewald G. von Kleist, who discovered it by accident.

  • electric.txt
  • Last modified: 2019/07/28 16:39
  • (external edit)