NavList:

I recommend the Casio fx260 solar calculator in my navigation classes. They're nice "scientific" calculators with all the usual trig functions. Solar-powered so there's no question about batteries. They're cheap and very widely available. Major US retailers like Walmart, Staples, Target, etc. usually stock them for $9, give or take.

Last week I looked at my little collection of these calculators (usually three or four are scattered about my apartment), and I noticed one was getting a bit beat up, so I decided to sacrifice the little goat, in the name of science. I dropped the calculator in warm saltwater and let it stew for about thirty minutes. Unsurprisingly, this calculator is not even remotely waterproof. It shut down moments after it hit the water, and it filled up rather quickly though it never completely sank. When I removed it from the water, I rinsed it for ten seconds in fresh tap water and toweled it down. Then I shook it for three minutes or so to get water to flow out from the spaces around the keys. The calculator no longer functioned. It appeared dead... I set it aside and let it air-dry for a while. About an hour later, I glanced at the calculator, and the display was showing its normal "0". It had come back to life.

An hour after drowning to death, the calculator didn't work very well, but it did correctly calculate the sine of 45° before going blank again. So I stood it up (figuring the water would be better off at the bottom of the case if it could flow at all) and left it overnight. Twelve hours later, the calculator was perfectly functional again --no problems, all keys working, all calculations normal, no display problems. Obviously I can't guarantee this performance in every case, but it's nice to know that this calculator can, in fact, survive drowning!

Frank Reed
Conanicut Island USA