Why a reflection on water cannot match the object
The eye above the water surface and the geometry of the mirrored image
The leaf argues that a thing mirrored on water cannot be similar in shape to the object being mirrored while the centre of the eye lies above the water's surface. A side figure shows the eye seeing the surface a b but not at e f, seeing the image's surface at r t but not the real thing c d, so that only an eye set on the water surface could see what the proposition denies. A second diagram below repeats the case; a later inscription reading like a shelf or catalogue note appears at lower left, outside the supplied transcription.
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A reflection on water cannot share the object's true shape
It is impossible for a thing mirrored on water to be similar in shape to the object, when the centre of the eye is above the water's surface. In the side figure the eye sees the surface a b but cannot see it at e f, and at r t it sees the surface of the image while not seeing it in the real thing c d.
Only an eye on the water surface could see the denied case
Therefore it is impossible to see what is stated above unless the eye is situated on the surface of the water. The lower diagram is drawn to demonstrate this condition, as the text says it is shown below.