Those crossing lines above and below the "Patent Hammerless Ejector" look to me to be intentionally engraved ledger lines or whatever they're called. Both are perfect and have a dot in the middle.

The longitudinal lines are what I believe the subject of this thread is about. After Hugh provided the explanation of the hand forging process of folding over bar stock, I can see where there may be what amounts to a linear inclusion of scale from folding over the bar multiple times.