at first sight, I though someone quite large got eaten in the night …. the choke
but a little investigation revealed ….
another astonishing act of nature
an Artichoke, who weathered the winter
Nancy Walker Studio
Ideas in Clay
at first sight, I though someone quite large got eaten in the night …. the choke
but a little investigation revealed ….
another astonishing act of nature
an Artichoke, who weathered the winter
Nancy Walker Studio 
Hello, what an interesting question! It is a dome, convex. It has spirals kind of like a sunflower pod, I think the spirals create this optical illusion you speak of.
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I wish I could “read” the last image. Is the brown part concave or convex? I see it as convex, but that doesn’t make sense to me. And concave doesn’t make sense to me either.
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