In a steam engine, hot steam expands under pressure, and part of the heat energy is converted into work. The idea to harness steam's power and convert it to mechanical energy dates back 2,000 years to Hero of Alexandria and his aeolipile, but the concept was not successfully applied to the building of a power source until about 1700. Improvements to the steam engine over the next century allowed it to play a major role in the Industrial Revolution. Why is there renewed interest in steam power?
Back in the day
The only remaining town gate of Berlin, the Brandenburg Gate was modeled after the propylaeum of the Athenian Acropolis. Originally topped with the "Quadriga of Victory," a statue of a chariot drawn by four horses, it was heavily damaged in World War II but was later restored. In 1961, the Berlin Wall blocked access to it for both eastern and western Germans, but it was reopened in 1989 with the reunification of East and West Berlin. The gate was the backdrop for what historic speeches?
Born on a day like today
Ramanujan was an Indian mathematician. Extremely poor, he was largely self-taught from age 15. In 1913, he began a correspondence with English mathematician Godfrey H. Hardy that took him to England, where he made advances, especially in the theory of numbers, the partition of numbers, and the theory of continued fractions. He died of tuberculosis at age 32, generally unknown but recognized by mathematicians as a phenomenal genius. What anecdote exists about Ramanujan and the number 1,729?