Air conditioning was first staged in 1620, when a Dutch inventor chilled Westminster Abbey

historyWikipedia1620 · Westminster, London, England

Air conditioning was first staged in 1620, when a Dutch inventor chilled Westminster Abbey

the gist

In 1620 the inventor Cornelis Drebbel showed King James I of England a demonstration called Turning Summer into Winter, cooling part of the Great Hall of Westminster Abbey with troughs and vats. The trick relied on salt or saltpetre mixed into ice, which absorbs heat as it dissolves and pushes temperatures far below freezing. Benjamin Franklin and John Hadley later showed in 1758 that fast evaporation of alcohol or ether could chill a thermometer bulb below the freezing point of water. The real breakthrough came from compression: in 1842 the Florida physician John Gorrie used a compressor to make ice to cool his hospital patients. Willis Carrier's 1902 system for a Brooklyn printing company, designed to control humidity so paper and ink stayed aligned, is widely regarded as the first modern air conditioner.

how it works

Evaporation absorbs heat, which is why sweating cools the body. Early systems dissolved salt in ice to absorb heat, while later machines compressed a gas so it heated up, released heat outside, then expanded and cooled sharply inside. Carrier's system also removed moisture by condensing water vapour on cold coils.

so what

Air conditioning began as a tool for industry and health, not comfort. Controlling humidity for printing and textile mills drove much of its early development.

fun fact

The first domestic air conditioner was installed in Minneapolis in 1914, in a house where its owner had already died.

From Wikipedia, the free encyclopedia · text CC BY-SA 4.0

Image: Wikimedia Commons

source: Wikipedia ↗

historyWikipediaclassic1336–1565 · Karnataka, India

Hampi was once one of the world's largest cities, until its Vijayanagara capital was destroyed in 1565

the gist

Hampi is a UNESCO World Heritage Site in Karnataka, India, with more than 1,600 surviving remains spread over 4,100 hectares. It was the capital of the Vijayanagara Empire from 1336 to 1565. Travellers from Persia and Portugal described it as a prosperous, wealthy and grand city with temples, markets and farms along the Tungabhadra River. By 1500 it was estimated to be the world's second-largest city after Beijing, and probably India's richest at the time. In 1565 a coalition of Muslim sultanates defeated the Vijayanagara Empire, its capital was conquered and destroyed, and the city was left in ruins. Hampi remains a religious centre, with the active Virupaksha Temple at its heart.

how it works

The city was built around a fortified core with temples, markets and water structures along the river, supplied by an extensive network of roads and waterworks. When the empire fell, the city was not rebuilt, so its stone monuments were left standing.

so what

Hampi shows how quickly a great city can vanish after a military defeat, and how a ruined capital can remain sacred. Its ruins give historians a view of medieval South Asia that few other sites can match.

fun fact

The name Hampi comes from Pampa, an old name for the Tungabhadra River.

From Wikipedia, the free encyclopedia · text CC BY-SA 4.0

Image: Wikimedia Commons

source: Wikipedia ↗

2 min

politicsshortCNA2:01

False allegations about Singapore’s hand in Indonesia’s markets and a made-up meeting

from CNA

CNA Verify has found close to 400 posts pushing falsehoods tying Singapore to Indonesia’s stock market rout and to a secret meeting that never took place. Together, they drew nearly 12 million views, and some were circulated by accounts that appeared to be working in concert, across multiple social media platforms.

Here’s how the disinformation campaign targeting Singapore was uncovered.

on YouTube: CNA ↗