MathBench > Measurement

Hemocytometers, or
How to count tiny things

captain flint of Treasure IslandCap. Silver's Roadside Spectacular... has an algae problem

For many years, Captain Flint’s Roadside Spectacular* was one of the grandest attractions in the country. People would flock to see the aquariums filled with creatures from the Seven Seas. In recent years, the number of visitors has declined and the facility has fallen into disrepair.

New owners have bought the place and they want to return the Spectacular the glorious state that they remember from when they visited as children. They envision waving fronds of kelp, explosions of coral reef, and something better than the same tired dogshark circling in its oversize fishbowl.

But first, they need to get rid of the vast quantities of algae that have built up over the years.

That algae is so thick you could cut it with a tablesaw.

It is so gunky you could use it to obscure small children.

It is so ... never mind, you get the idea.

So, this is the story of how the workers at the Cap. Flint's Spectacular went about figuring out just how much of that algae there was.

Or more exactly, how they tried to go about it. The problem is that algal cells are actually harder to count than one might expect - after all, they are quite small and hard to focus on. So, our enterprising fish-lovers will have to work their way through counting some larger organisms first, and hone their methods, until they get to a point where algae will be a piece of crabcake.


* Names have been changed to protect the innocent.