Why is a meter exactly one meter long? MEASURE OF ALL THINGS offers that answer, revisiting Delambre's and Mechain's 1792-99 meridian expedition to calculate the length of the meter. Alder draws on original documents that describe not only the journey but also a mistake in calculation and its cover-up that would haunt Mechain over the years. Copyright (C) Muze Inc. 2005. For personal use only. All rights reserved.