Tears

I have a new fascination with tears - specifically: where do they come from, where are they stored, and why haven't I lost 50 pounds in water weight over the last couple of years?

So I went to Wikipedia to discover that there are three kinds of tears. There are basal tears, which lubricate the eye and help keep it clear of dust. Then there are reflex tears, filling our eyes when there are foreign substances that need to be flushed out (think onion vapors, spicy foods, etc). Finally there are crying or weeping tears, also known as "psychic" tears. These erupt "...due to strong emotional stress, suffering, mourning, or physical pain."

What's very intriguing is the fact that "...tears brought about by emotions have a different chemical make up than those for lubrication." Isn't that amazing?

Here is how Harvard Health Publications describes the process of crying:

"At the inner corner of each upper and lower eyelid is an opening to a small tube or tear duct. The tear ducts carry tears to the eye so the eye can be rinsed. Your tears are made by a small organ below your eye called the lacrimal gland, and they are stored in your lacrimal sac. Your lacrimal sac is connected by a tube to each tear duct, and to the inside of your nose. Tears spill out of the eyes and into the back of your nose when you cry, although the tears entering the nose are not visible."

My final step was to find out more about this lacrimal sac. According to answers.com "...it is oval in form and measures from 12 to 15 mm. in length; its upper end is closed and rounded; its lower is continued into the nasolacrimal duct." Here is a link to a diagram of all this for those who are interested: http://commons.wikimedia.org/wiki/File:Tear_system.svg

Nowhere could I find an explanation as to how the process works that pumps out hours of tears from something that is only 12 to 15 mm. in length.

Those are the physical facts. Tomorrow we'll look at tears from another source. Can you guess which one?