|
Burning-glass
A burning glass or burning lens is a large convex lens that can concentrate the sun's rays onto a small area, heating up the area and thus resulting in ignition of the exposed surface. Burning mirrors achieve a similar effect by using reflecting surfaces to focus the light. They were used in 18th-century chemical studies for burning materials in closed glass vessels where the products of combustion could be trapped for analysis. The burning glass was a useful contrivance in the days before electrical ignition was easily achieved. Historical development: from legend to science Burning glass technology has been known since antiquity, as described by Greek and Roman writers who recorded the use of lenses to start fires for various purposes. Pliny the Elder noted the use of glass vases filled with water to create a heat intense enough to ignite clothing, as well as convex lenses that were used to cauterize wounds. Plutarch refers to a burning mirror made of joined triangular metal mir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Priestley Burning Lens Replica
Priestley may refer to: Places * Priestley, West Virginia, US, an unincorporated community * Priestley Glacier, a major valley glacier in Antarctica * Priestley (lunar crater), on the far side of the Moon * Priestley (Martian crater) * 5577 Priestley, an inner main belt asteroid People Arts * Alice Priestley (born 1962), Canadian children's writer and illustrator * Brian Priestley (born 1940), English jazz writer, pianist and arranger * Chris Priestley (born 1958), British children's book author and illustrator * Jason Priestley (born 1969), Canadian-American actor * J. B. Priestley (1894–1984), English writer and broadcaster * Mark Priestley (1976–2008), Australian actor *Rick Priestley (born 1959), British miniature wargame designer and author * Robert Priestley (1901–1986), American set decorator * Tom Priestley (born 1932), sound and film editor Sciences * Henry Priestley (biochemist) (1884–1961), Australian biochemist * Hilary Priestley, British mathematician * J ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roman Navy
The naval forces of the Ancient Rome, ancient Roman state ( la, Classis, lit=fleet) were instrumental in the Roman conquest of the Mediterranean Basin, but it never enjoyed the prestige of the Roman legions. Throughout their history, the Romans remained a primarily land-based people and relied partially on their more nautically inclined subjects, such as the Greeks and the Egyptians, to build their ships. Because of that, the navy was never completely embraced by the Roman state, and deemed somewhat "un-Roman". In antiquity, navies and trading fleets did not have the logistical autonomy that modern ships and fleets possess, and unlike modern naval forces, the Roman navy even at its height never existed as an autonomous service but operated as an adjunct to the Roman army. During the course of the First Punic War, the Roman navy was massively expanded and played a vital role in the Roman victory and the Roman Republic's eventual ascension to hegemony in the Mediterranean Sea. In th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
