Mathematics : Shelter Harbor Press : 9781627950954 : 1627950958 : 11 Oct 2017 : This revised edition includes an updated removable foldout concertina neatly housed in the back of the book, providing a 12-page timeline that traces the history of mathematics from the very beginning all the way up to 2017. The reverse side features some of the greatest mathematical enigmas and interesting facts about the world of numbers. Legend has it that the first magic square, where all lines and diagonals add up to the same figure, was revealed more than 2,000 years ago when a river turtle appeared to have ancient Chinese numerals inscribed on sections of its shell. Patterns are everywhere in nature, and counting, measuring, and calculating changes are as old as civilization itself, as are many of the theorems and laws of math. The Pythagorean Theorem was used to plot out fields for planting crops before Pythagoras was even born, but the story begins long before that, with tally marks on rock and b