works*

sorry, i had imperfect sight when i wrote that. the natural eye's
refraction is variable, a fact that can easily demonstrated by having
the patient look at a blank wall without trying to see, an objective
observer measuring the refraction with a retinoscope (an objective
scientific refraction tester).

Mike Turner's like "DOH!!!"

Thanks.  I wasn't sure whether or not I should add you to my twit filter.  Now
I am.