Greg Lone asks "... Armstrong Moth ...when these frames were made? ..."
Some datapoints...
The 13 December 1929 issue of Cycling on page 552 reviews the Moth, and says it was "produced two years ago..."
The Moth appears in the 1951 and 1956 Armstrong catalogues
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Peter Brueggeman
La Jolla California USA
4peebee(at)peterbrueggeman.com