My Dearest Anais,

Rainbow

Thank you very much for your letter. I am particularly happy to hear that you still like your class after the first week and especially that you are working hard on spelling and math.

Tubeworms

Now, about the tube worms...It was not exactly my intention to suggest that tube worms might be good pets. Noooooo, indeed not. I suppose you are thinking that they might go into the tank with our fish, Gourmand, but Gourmand lives in fresh water. Now you remember what the ocean taste like--it's rather salty. If you rummage around in one of the bottom cabinets in the kitchen you will find a liter measuring cup and a small scale (Maman, of course, will know where these are). If you fill that measuring cup with water and add to it exactly 30.2 grams of salt and then mix it up until all the salt is gone--well, that's how much salt sea water has. Please do that over the sink, by the way.

Remember what I said about the bacteria that do all the eating for the tube worms. They eat chemicals, in particular something called hydrogen sulfide. As a gas, hydrogen sulfide smells like rotten eggs, and that's basically what you would have to make in the fish tank. My biologist friends tell me that they can make food for tube worms in tanks in their laboratories--rotten vegetables and a few other goodies apparently do the trick--but by this time Gourmand would be gagging, if fish gag, as would the rest of us.

Inside Jason control van

One thing in the tube worms' favor, is that they can live at almost any temperature. The water on the bottom of the ocean is 2 degrees Celsius, which is about 36 degrees Fahrenheit, or ever so slightly above freezing, and tube worms can live at that temperature. But such cold water can't hold much hydrogen sulfide, so the tube worms that live in those places look a bit ill--sort of like you will look like if you don't eat dinner. On the other hand, we see big fat tube worms that live on top of the sulfide chimneys where the water is like the water in your bath--40 degrees Celsius (or 103 degrees Fahrenheit). It's not the temperature that makes them fat but the fact that the water contains a lot of hydrogen sulfide.

The real problem with keeping tube worms as pets is pressure, which we don't think about very often. The floor of the ocean where we are right now is about 2000 meters (which is exactly 6562 feet, or more than a mile, if that's easier to think of) below us. Now just imagine how heavy a bucket of water is--you can barely lift it, right? Say each bucket is one foot high and one foot on each side. You lie on the ground, and I put the bucket on top of you. That's okay. Then I put another on top of that. Less okay and now you're thinking this is only maybe fun. Then another--now you're hurting. The pile increases to ten, then twenty, finally to 6,562 buckets. That is equal to 29,000 pounds on every square inch of your body, so you are squished, flat as a pancake, way beyond even burnt toast. But, that's what tube worms like, and in fact they don't like it any other way.

Alvin

So, the short answer is no, tube worms do not make good pets.

Well, that's all I have to report today. A storm is supposedly approaching. The promised big waves have yet to arrive, and the storm may pass us by with nothing more than a whimper. Because of the threat we were unable to launch the submarine, and everything on the ship is tightly tied down. I was up most of last night helping with a sonar survey, which allows us to see what the ocean floor looks like. Perhaps we'll get more done tomorrow.

Love, Papa