Normal dating timeline
In 1901 a London-based engineer named Hubert Booth saw a new American device for extracting dust from the upholstery of railway carriages.It used compressed air to blast the dust out, which was all very well, except the dust settled straight back on the furniture again.Many inventions have had a Darwinian-like evolution, with rival companies vying to come up with ever-better products, to the benefit of the consumer. For the best part of a century the basic design remained a dinosaur in the technological Lost World.The first vacuum cleaner was a fairly silly idea cooked up in response to a really silly one.Warm air in the room heated the ammonia which evaporated, absorbing heat and cooling the air until it reached its dew point.The droplets that formed on the coils drained away and a fan returned the cooler, drier air to the printing plant.He called these distinct signals the "pqrs" factors.However, Einthoven needed an exact way of measuring the minute amounts of current.
Then, in 1895, a brilliant young Dutch physiologist, Willem Einthoven, used a crude electrical sensing apparatus to establish that the beating heart produced four distinct signals, each one corresponding to a different ventricle.
Radar [1904, Christian Hülsmeyer by James Dyson] During the war, my mother worked for Bomber Command, shunting those little flags representing planes around the map of Europe.
She could plot things hundreds of miles away thanks to radio detection and ranging, now known as radar.
Then in 1935, the Scottish physicist Robert Watson-Watt of the National Physical Laboratory near Slough was asked by the Air Ministry to investigate the possibility of using a beam of radio waves as a death-ray weapon.
Watson-Watt found that radio transmitters lacked the power to kill, but that they could trigger echoes from aircraft almost 200 miles away.