The human eye is a wondrous thing, filled with receptors, lenses and irises that open and close. An eye admits light, focuses and captures images both near and far away. But when locked into position and focused on one image only inches away -- like small print or a computer screen -- hour after hour, muscle stress sets in, often resulting in severe eyestrain. The symptoms are burning or stinging sensations paired with blurriness and headaches. Muscles that control the eyes, and focus and aim them where you want, get tense and contract when held in one position for a long time. The eyeball gets rounder, straining its focus. Give eyes a short break every hour. By looking away or out a window you allow muscles to relax and lenses to flatten. The result: less eyestrain and more endurance. And that's the On The House tip for today.