That's cearc

that's the ark → Noah's Ark

• the fairest sin the sunsaw (that's cearc!) → "the fairest sign the sun saw (that's the ark!)" – suggests a reversal of perspective, the sun seeing the "sign" of the ark, instead of Noah seeing the sign of the rainbow → the Hen gathering goods in her knapsack also collects a rainbow or an ark → the image of the Hen collecting things in her knapsack may thus be a parallel to Noah collecting animals in his ark

cearc: (Irish) hen

• ceart: right; correct