Urticaria is also known as 'nettlerash' or 'hives'. It consists of wheals-spots or patches of raised red or white skin-each of which usually clears away in a few hours, to be replaced by other fresh wheals. The wheals are usually itchy, painful or cause a burning sensation.
1 1893: the original Ferris Wheel was 80.4 metres (264 ft) tall. 2  Built for the World's Columbian Exposition in Chicago, Illinois, it was moved to St. Louis, Missouri, in 1904 for the Louisiana Purchase Exposition, and demolished there in 1906.
Click here for audio of Episode 1254. Today, another look at the invention of the wheel. The University of Houston's College of Engineering presents this series about the machines that make our civilization run, and the people whose ingenuity created them. It's fairly common knowledge that the wheel was invented around 5500 years ago. But what was really invented at that time? V. Gordon Childe offers an interesting slant on the question. What we should be looking at, he says, is not the wheel itself, but rather the use of rotary motion.