I think it is die deterioration doubling he saw in the date and LIBERTY, best I can do with the magnification, Jim
Look at the N in UNITED and the ON in ONE, on the reverse. He may have seen that as doubling. I know when I first started searching pennies, I would save all of that kind of stuff that I found. I still have several large Coffee-Mate tubs full of cents with doubling like that on them. Then I found out that, Yes, it's doubling, but it's the "No Added Value" type of doubling.