Echelon
Running time	5.48
Appears on	Play By Numbers

Trivia

• Echelon is the term popularly used for an automated global interception and relay system operated by the intelligence agencies in five nations: the United States, the United Kingdom, Canada, Australia and New Zealand (it is believed that ECHELON is the code name for the portion of the system that intercepts satellite-based communications)" - quote from echelonwatch site [1]. See also this report [2]. This system has been around since the early 70's, but did not become more widely known until the governments of Australia and New Zealand unwittingly admitted to its existence only a few years ago. The US government still declines to comment on its existence.
• A more mathematical connection with the title is as follows; a correspondent has reminded me of the "row-echelon form" of a matrix, used in solving systems of linear equations. There is also the simple definition of an "echelon" as a particular geometrical shape.
• Others: military troop or aircraft formations - arrangements in parallel lines. In the Navy, the classic "V" or "wedge formation". And "Echelon lens: a large lens constructed in several parts or layers, extending in a succession of annular rings beyond the central lens; used in lighthouses." In all instances, it relates to a particular kind of regularity of arrangement; "echelon" is in fact the French word for a rung of a ladder. [Pat N.]
• Ultimately from Lat. "scala" - "a ladder", from which we get the word "scale".
• A possible connection with cycling (as in "Happy Cycling"): when a group of cyclists are in a staggered formation to offset the effect of a crosswind, that is called an echelon. [bodhisattva cam]