Rivers were used to turn watermills and the Romans even used geothermal water for heating. Until the middle of the 18th century renewable sources of energy were the only forms of energy available, but then, with the advent of the Industrial Revolution, fossil fuels began to be exploited.
The Sidereal Zodiac is the position of the sun referenced against the star background, as a measure of the flow of time. The framework for the star background is the constellations the sun passes in front of. This is the one astronomers use.
By Molly Hall. There's nothing New about the sidereal Zodiac, but here are the dates for you to find where you fall in this system of measuring the sky. Each year, just like with the Tropical Zodiac, there's often a shift of a day in either direction. Aries: April 18 - May 13. Taurus: May 13 - June 21. Gemini: June 21 - July 20.