I don't think they made a mistake and simply transitioned from doing Broadleaf to Lenox then corrected.
While it is a nuisance to swap inks, I would think it was a bigger nuisance to swap out what was likely a 200+lb stone, bring in a different one, properly align it and continue. Unless conditions were just right the partially dried ink would cause all sorts of problems.
A third suggestion?
Since we can be fairly sure the fronts were printed, then backs added.
AND
Being efficient and delivering multiple brands at about the same time was also likely.
Two presses were in use, possibly next to each other. For whatever reason both were loaded with brown ink until it was noticed that the Lenox ones should have been black and the ink changed out, possibly partly at first. (Much easier to scoop out nearly all the brown and fill with black without a complete washdown. That could probably be done with the press still running. )
There are other possibilities, but they're all extremely unlikely.
The Philatelic foundation now apparently has a spectrometer. If I owned a couple examples, I might be inclined to ask them if they'd be interested in working up some cards. (It would be able to tell between a carbon black ink and a chemical black. And tell if the brown inks were identical or not. ) There's a group doing some of that work on inks and papers that has already put down some longstanding beliefs. Like the inks for the very first US stamp being colored with rust leading to premature plate wear. The spectrograph says..... theres no iron at all there!
|