In October, Ken Alder, the author of The Measure of All Things, gave a one-hour talk (including a question and answer period) at a bookstore in Winnetka, IL.
I was lucky enough to capture it just over an hour ago (at 00:00 PST) on CSPAN-2. As we've discussed here, already, the focus by reviewers on Mechain's error (and Delambre's cover up), does not represent Alder's position. He sees the recognition of the error as the beginning of an awareness of the concept of uncertainty and points out that, in any case, the very slight "lumpiness" of the Earth gives rise to variations in the length of a meridian, depending on which meridian is measured. In no way does Alder claim that the fact that the original platinum bar is not precisely one ten millionth of the length of the meridian passing through Dunkirk and Barcelona invalidates the metric system. He also pointed out that the current, really precise definition is the one based on the speed of light (as documented in BIPM's SI Brochure). Alder is quite obviously pro-metric, although he is very low key about that. He's a historian and, as such, is not on a mission to actively promote the metric system in the U.S. However, in answer to a question, he pointed out that this country has already gone metric in a number of fields (which I don't need to enumerate for the members of this list). His prediction (which assumes the current permissive approach) is that the adoption of the metric system (he never refers to it as SI -- at least not in his oral presentation) in everyday transactions (e.g., consumer purchases) is going to take many years. He points out that, even in France, the use of metric measures among the common people was not fully accomplished until the beginning of the 20th century. I haven't yet bought the book. However, based on his talk, it would seem to make very interesting reading. Bill Potts, CMS Roseville, CA http://metric1.org [SI Navigator]
