Common practice in the printing industry was to date the printing plate. I suspect the date is the plate date. They would pour the plate and make a press run for the larger customers. At some point the 11/20/12 plate would be considered worn out and melted down or tossed. On Fri, 22 Jun 2007 17:10:14 -0400, gpaul2000 at aol.com wrote: > Andy, >Looks like you're narrowing the window of possibility for your machine's manufacture - and the clues were right there all along!? I don't have a sense of how long it took for new patent dates to appear on Edison dataplates, as this would imply that newly-patented features appeared on those particular machines.? I suspect that the time varied, depending on whether the model in question was a faster- selling one (such as the "A-250") or slow-selling one (such as the "A-150") with larger inventories of unsold machines.? In any event, based on the evidence you've discovered today, I'd amend my earlier assessment to "late 1912/early 1913" for your example.? Here's a puzzler: you state that Form 632 (pasted to your "A-250") is dated 11/20/12.? I have Form 632 pasted to an "A-80" and it has NO DATE ON IT.? What do you suppose that means?? Those fellows at West Orange didn't make this easy for us, did they? >George Paul >________________________________________________________________________ >AOL now offers free email to everyone. Find out more about what's free from AOL at AOL.com. >_______________________________________________ >Phono-L mailing list >http://phono-l.oldcrank.org