The next year didn't go so well. The technician was inexperienced and didn't do as well as the previous one and I ended up with a bruise. Well, so much for that, but at least now I knew I'm type O negative. Universal donor. Common as dirt.

When I returned to Minnesota, I called the Arrowhead Regional Blood Center in the Burning Tree Plaza and offered to donate. Now, almost five years later, they know me by name. They have to, because every one of them, at one time or another, has taken, or tried to take, my blood.

Since I've spent a bit of time there, I've learned a few things about blood.

It isn't only AIDS they're worried about. The questioning at every visit is extensive and, frankly, intrusive. Fortunately, because I'm an old-maid librarian, I always give them the answers they want. I've never had hepatitis. I've never been pregnant, no heart attacks or cancer, haven't been to Central Africa lately, and when the question comes through the pipeline soon, nor have I been to England recently. I haven't been incarcerated and I haven't traded sex for drugs. I've never taken a growth hormone, and I haven't experienced an unexplained weight loss recently. Ha. However, if I'm ever a recipient, I'm going to be so glad to know how very thorough they are: they only take blood if they're sure there won't be any problems.

I've learned to guzzle water earlier in the day when I plan to donate. It turns out that I have these teeny, little veins. Owie. However, if I've had a lot of water and juice to drink in the 24 hours before I donate, my veins will be nice and plump and, uh, bloody. Before I figured this out the technicians had the hardest time getting my blood. They'd prod and they'd poke, apologizing for taking off their gloves for greater fingertip sensitivity, as if it was their fault I have these teeny, little veins.

I've learned about type O-. I'm the universal donor for red blood cells, but not for plasma. O- is not common as dirt, but because the red blood cells can be transfused to anyone, it's the most useful. I may be the universal donor, but I am the opposite of a universal recipient: I can only receive O-. That means that, while everyone else can receive their own type plus mine, I can only receive my own type - I have the smallest pool