Not an expert but the canadians look as though they could have been struck through grease and i cannot really see what your referring to on the lincoln, they are known for double dies though. Im sure an expert will tell you whats up though.
The little bumps are common on the later zinc cents something about gas forming and bubbling up after the cent is coated with copper, although nothing i say should be taken as being for certain as i am not an expert.
The 2majority canadians appear to be struck through grease. The lincoln i cant tekk for certain but i believe as stated above that it may have a gas bubble underneath the copper coating
