Hi. This is my first post here. Site looks very cool; can see myself spending some time here, if I have it to spare. Anyway, to the point of the thread: I'm a bit puzzled over something. Numerous texts I've read on eye anatomy/physiology claim that is the cornea that is responsible for most of the eye's refractive power. Can someone please explain to me how this could be the case? I would have thought that, considering that the tangents to the points of entry and exit of light rays passing through the cornea are appxoximately parallel, the overall refractive power of the cornea would be very little. I would have thought, therefore, that light passing through the cornea would behave in the manner depicted in THIS diagram (..assume that the mediums on either side of the cornea have the same refractive index, as would be the case when underwater for example, as water and the aqueous humour have approx. the same refractive index.) It seems to me that it is the aqueous humour, as opposed to the cornea, that is responsible for most of the refractive power of the eye. So I don't understand why most of the texts I'm reading state otherwise. Can anyone help me out? Am I missing something? Is it conceivable that the texts I've read are wrong on this point? P.S. I think my treating of the opposite sides of the cornea as approx. parallel is quite reasonable, and is based on pictures you can see for yourself here,here and here.