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John Walsh (scientist) John Walsh (1 July 1726 – 9 March 1795) was a British scientist and Secretary to the Governor of Bengal.

John Walsh (scientist)

John was son of Joseph Walsh, Secretary to the Governor of Fort St. George and cousin to Nevil Maskelyne, the Astronomer Royal, and his sister Margaret, the wife of Lord Clive. In later life, John Walsh's interests were scientific. Alessandro Volta. Early life and works[edit] Volta was born in Como, a town in present-day northern Italy (near the Swiss border) on February 18, 1745. In 1774, he became a professor of physics at the Royal School in Como. A year later, he improved and popularized the electrophorus, a device that produced static electricity. His promotion of it was so extensive that he is often credited with its invention, even though a machine operating on the same principle was described in 1762 by the Swedish experimenter Johan Wilcke.[3][4] In the years between 1776–78, Volta studied the chemistry of gases.

In 1779 he became a professor of experimental physics at the University of Pavia, a chair that he occupied for almost 40 years. Volta and Galvani[edit] Luigi Galvani Luigi Galvani discovered something he named "animal electricity" when two different metals were connected in series with the frog's leg and to one another. First battery[edit] Voltaic pile zinc Zn → Zn2+ + 2e− sulfuric acid 2H+ + 2e− → H2. Lunar Society of Birmingham. The Lunar Society of Birmingham was a dinner club and informal learned society of prominent figures in the Midlands Enlightenment, including industrialists, natural philosophers and intellectuals, who met regularly between 1765 and 1813 in Birmingham, England.

Lunar Society of Birmingham

At first called the Lunar Circle, "Lunar Society" became the formal name by 1775. The name arose because the society would meet during the full moon, as the extra light made the journey home easier and safer in the absence of street lighting. The members cheerfully referred to themselves as "lunarticks", a pun on lunatics. Venues included Erasmus Darwin's home in Lichfield, Matthew Boulton's home, Soho House, and Great Barr Hall. Membership and status[edit] The Lunar Society evolved through various degrees of organisation over a period of up to fifty years, but was only ever an informal group.

Development[edit] Origins 1755–1765[edit] Radium. Radium is a chemical element with symbol Ra and atomic number 88.


Radium is an almost pure-white alkaline earth metal, but it readily oxidizes on exposure to air, becoming black in color. All isotopes of radium are highly radioactive, with the most stable isotope being radium-226, which has a half-life of 1601 years and decays into radon gas. Because of such instability, radium is luminescent, glowing a faint blue. Radium, in the form of radium chloride, was discovered by Marie Curie and Pierre Curie in 1898. They extracted the radium compound from uraninite and published the discovery at the French Academy of Sciences five days later. In nature, radium is found in uranium ores in trace amounts as small as a seventh of a gram per ton of uraninite. Characteristics[edit] Physical characteristics[edit] Pure radium is a white, silvery, solid metal, melting at 700 °C (1292 °F) and boiling at 1737 °C (3159 °F), similar to barium. Chemical characteristics and compounds[edit] Richard Trevithick.

Richard Trevithick (13 April 1771 – 22 April 1833) was a British inventor and mining engineer from Cornwall, England, UK.[1] Born in the mining heartland of Cornwall, Trevithick was immersed in mining and engineering from a young age.

Richard Trevithick

The son of a mining captain, he performed poorly in school, but went on to be an early pioneer of steam-powered road and rail transport. His most significant contribution was to the development of the first high-pressure steam engine. He also built the first full-scale working railway steam locomotive. On 21 February 1804 the world's first locomotive-hauled railway journey took place as Trevithick's unnamed steam locomotive hauled a train along the tramway of the Penydarren Ironworks, in Merthyr Tydfil, Wales.[2][3] Turning his interests abroad, Trevithick also worked as a mining consultant in Peru and later explored parts of Costa Rica. Childhood and early life[edit] Trevithick first went to work at the age of 19 at the East Stray Park Mine.