Sound or acoustic mirrors were one of the first early warning detection systems invented to give advanced notice of an approaching enemy aircraft. These worked by focusing the sound from the plane’s engine so it could be heard before it was visible.
Sound mirrors worked using a curved surface to concentrate sound waves into a central point, which were picked up by a sound collector and later by microphones. An operator using a stethoscope would be stationed near the sound mirror, and would need specialist training in identifying different sounds. Distinguishing the complexity of sound was so difficult that the operators could only listen for around 40 minutes.
On Saturday 26 June 2021 there was a massive protest against government regulatory abuse in the UK.
Some protesters were seen throwing tennis balls at the Houses of Parliament. One protester, who did not wish to be named, said: “They have little messages on them. Most of them are not very nice.” – BBC Report
Self-taught John Harrison spent 43 years overcoming engineering challenges to develop the first marine chronometer. Harrison won a British competition to resolve deep sea navigation problems, but it took him several years to win the full prize.
In 1714, the British government offered a longitude prize for a method of determining longitude at sea, with the awards ranging from £10,000 to £20,000 (£2 million to £4 million in 2019 terms) depending on accuracy. John Harrison, a Yorkshire carpenter, submitted a project in 1730, and in 1735 completed a clock based on a pair of counter-oscillating weighted beams connected by springs whose motion was not influenced by gravity or the motion of a ship. His first two sea timepieces H1 and H2 (completed in 1741) used this system, but he realized that they had a fundamental sensitivity to centrifugal force, which meant that they could never be accurate enough at sea. Construction of his third machine, designated H3, in 1759 included novel circular balances and the invention of the bi-metallic strip and caged roller bearings, inventions which are still widely used. However, H3’s circular balances still proved too inaccurate and he eventually abandoned the large machines.
Harrison solved the precision problems with his much smaller H4 chronometer design in 1761. H4 looked much like a large five-inch (12 cm) diameter pocket watch. In 1761, Harrison submitted H4 for the £20,000 longitude prize. His design used a fast-beating balance wheel controlled by a temperature-compensated spiral spring. These features remained in use until stable electronic oscillators allowed very accurate portable timepieces to be made at affordable cost.
£20,000 in 1714 = ±£3,837,000 in 2018 = ±$4,733,000 USD.
$110k/year is not a bad payoff for a 45 year-long side project. Harrison began as a 21 year-old, and was 66 when he resolved the problem and received the full amount of the prize. He died 17 years later in 1776.
Kinder Downfall is the tallest waterfall in the Peak District, with a 30-metre (98 ft) fall. The waterfall was formerly known as Kinder Scut, and it is from this that the plateau derives its name. Although usually little more than a trickle in summer, in spate conditions it is impressive. In certain wind conditions (notably when there is a strong west wind), the water is blown back on itself, and the resulting cloud of spray can be seen from several miles away. [Wiki]
[Found here, via here. 1st link has a video that blows me away.]
Although the World Cup actually began yesterday somewhere in Africa, the USA team kicked England’s arse in a tie of 1-1. I’ll explain why shortly.
The game supposedly originated when victorious Brits began a game of kicking around the skull of a dispatched Roman soldier. Eventually the skull was replaced with an inflated sheep’s bladder (brilliance), and they began kicking that up and down the path between rival villages. The game spread to other villages, and gained the name of “Association Football,” abbreviated to “Assoc.” A participant was termed an “Assoc-er,” thus was the game of Soccer introduced into the English speaking world.
I doubt the previous summary is entirely accurate, but humor me for the attempt at historical improvisation.
Most Americans these days are introduced to Soccer (or Football as the rest of the civilized world calls it) via AYSO, an excellent organization that introduces their kids to the sport and allows parents to yell at each other with impunity over rules they don’t understand. The offsides rule is particularly difficult for us yanks to comprehend because you can’t actually see it unless you are standing right behind the line judge (who is constantly in motion up and down the sidelines) when the foul occurs.
So today, England, the ancestral homeland of the sport, was supposed to have had an easy win over the supposedly inept USA team. It was expected to be a blowout, and with a goal within the first five minutes of play, England led by infinity. However, in the last few minutes of the first half, the Brit keeper floundered allowing a tie score. He’s on suicide watch now, although it wasn’t entirely his fault as nine of his own teammates blew it before the bladder even reached him.
The USA team should be proud, even at a final score of 1-1. England got their pointy little noses polished. Now we’ll work on their teeth.