Segments and a circle with the axiom on equal magnitudes
"If two things are equal to a third, they will be equal to one another"
At the top the sheet carries two line segments, the first (a–b) struck through with the pen and a second labeled c–d. Below, a segment a–b is set over a circle drawn with two radii, one radius extended beyond the circle and then canceled, with two lines linking the radii to the segment. The accompanying note states the Euclidean common notion that things equal to a third thing are equal to one another. Further faint writing, largely show-through, appears at the foot of the sheet and is not part of the transcription.
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Common notion: things equal to a third are equal
A segment a–b is placed over a circle with two radii, one extended past the circle and canceled, and two lines connect the radii to the segment. The note states that if two things are equal to a third, they will be equal to one another.