Gold pencilled hamburgh/golden campines?

Dear (more knowledgeable than me) Folks,
A few questions: Having recently acquired some campines, and possibly
already having a gold pencilled hamburgh (left behind on the farm by a
previous owner), can anyone here pls give me a quick guide as to how best
distinguish them? They look very similar to me.
Are both breeds' eggs of similar size?
And are they both predominantly non-sitter breeds?
Lastly, in their natural state how have such non-sitting breeds survived
through the ages - if the norm is that they don't tend to go broody?
Cheers
Craig


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