The primary purpose of this study is to evaluate the effects of ocular physical properties on intraocular pressure (IOP) measurements in eyes with healthy corneas using the following instruments to measure IOP: Goldmann applanation tonometer, pneumotonometer, ocular blood flow pneumotonometer, Tono-Pen, Pascal Dynamic Contour Tonometer and the Schiotz Tonometer. Ocular physical properties to be evaluated are:varying (CCT), corneal curvature (CC), axial length, anterior chamber depth and scleral rigidity. The secondary purpose of this is to determine if there is a correlation between CCT and other ocular properties, and which instruments that measure these other ocular properties are most affected by CCT.