Joy of Pi

It is hardly an overstatement to call pi the most important number in the history of civilization. For thousands of years, pi--the ratio of the circumference of any circle to its diameter, or 3.14159265...--has been a source of fascination, because the digits after the decimal point never fall into a recognizable or repeating pattern. Famously inquiring minds, like Leonardo da Vinci and the great Indian mathematician Srinivasa Ramanujan, have been driven to discover the next, unknown digit. In this slim, elegantly designed book, Blatner, an expert in computer publishing who has authored books on digital imaging and virtual reality, takes the reader on a colorful, visually rich tour through this still incompletely known number's rich history as a mathematical holy grail. As mathematicians continue to determine pi's value to more and more digits, now up to at least 8 billion, sidebars, quotations, cartoons and numerous images provide clever or informative asides and bits of trivia. (Want to know the 71,297th digit of pi? You'll find it here.) Such digit-chasing at times threatens to overwhelm the myriad roles the ratio has played in everything from the construction of the Egyptian pyramids to the oscillation of mechanical systems and electrical current. Quibbles aside, however, this is a book ideally suited to being left lying about, so that science buffs and aficionados of fine typography can peruse it at leisure. (Dec.)