Click for bigger picture.I got so excited tonight! I was getting ready to clean our little 20 gallon aquarium, and I noticed that the glass was crawling with a bunch of hydras! Now, the only experience I’ve had with hydras was some pictures in my High School biology book, but these guys are the real deal, and they look hungry.

They range in size anywhere from about 1/8th to 3/16th of an inch (or as we Americans like to say, a couple-three millimeters), and they’re clearly visible to the naked eye. They look a lot like pieces of lint with serious intentions.

I collected several and looked at them under both of the microscopes that I bought last fall, and they look fantastic under our fairly decent optical microscope, but the blue toy microscope that hooks up to a USB port has a hard time picking them out from the background noise – even though they look as green as this one in my ‘good’ scope, they look almost white otherwise, and of course, they don’t stand still or even lie in a plane, and ol’ Blue didn’t seem to want to focus on anything, even though I was looking at the little guys right there on the stage.

So, the bottom line is that I tried really really hard to get you a picture of one of my hydras, but I just didn’t have the resources, so this is the most representative sample I could find on Google, and I looked at several dozen and this is the best I could come up with. (Hey, worse things have happened.)

Buy me & Read me. Now.I’m currently reading The Evolution of Useful Things by Henry Petroski, which is all about stuff like paper clips, staples, and forks, and it’s absolutely fascinating.

One of the things that’s occurred to me this evening is that, while I have to work hard to convice our 4 year old that mommy and daddy didn’t have computers when we were growing up, my parents had to work hard to convince me that they really didn’t have televisions. But here’s what I was thinking about – Janet’s Grandmother, or my Great Grandmother (or yours) probably had a couple of Edison light bulbs (patented 1879), and maybe even a phone (1876) or a car (Model T’s were $950 in 1908, which actually seems kinda steep), but they didn’t have paper clips (1901) staplers (1923) or Scotch&#153 tape (1930). I’m guessing when some of this stuff came out, it was a lot like 1980 or ’81, when a saw Post-It&#153 notes for the first time, and I thought, ‘Now why would anybody want that?’ Kinda weird, huh?