The force of attraction increases as an electron and a proton approach each other. And it varies inversely as the square of the distance between the particles. The electron and the proton have a negative electrostatic charge and a positive electrostatic charge respectively. Each charge-and the force associated with that unit of charge-is constant-and equal.
There are pools/baths dating as far back as the Ancient Greeks and Ancient Egypt however I believe there would have been something far more prehistoric than this (albeit far less advanced). The first heated swimming pool was built by Gaius Maecenas of Rome in the first century BC. Gaius Maecenas was a rich Roman lord. The great bath at the site of Mohenjo-Daro was most likely dug during the 3rd millennium BC. This pool is 12 by 7 meters, is lined with bricks and was covered with a tar-based sealant.
Fifteen-Ball Pool was played with 15 object balls, numbered 1 through 15. For sinking a ball, the player received a number of points equal to the value of the ball. The sum of the ball values in a rack is 120, so the first player who received more than half the total, or 61, was the winner. This game, also called 61-Pool was used in the first American championship pool tournament held in 1878 and won by Cyrille Dion, a Canadian.