Measuring Water for Dummies

Meniscus

You might think that the research team here at the Antisocial Network would be rather jaded by some of the strange – even ridiculous – topics that people tried to address in the good old days of eHow.com and other content farms. One type of question that never ceases to amuse is the "how could anyone be so stupid?" question. Of course, eHow freelancers were eager to find those because it gave them a quick ten, fifteen, even twenty-five bucks. The problem, as demonstrated by today's DotD, is that the writer was often the "stupid" one. Watch OurEverdayLife.com writer Kelly Taylor as she buzzes through "How to Measure a Cup of Water."

We know Taylor didn't bother to wonder why someone would ask that; she just powered through an "answer," starting with the introduction required of all eHow posts:

"The job of a measuring cup is to measure liquid, especially water that's used for cooking and baking. North America measures in cups and ounces, while the United Kingdom uses pints, ounces and metrics. Much of the rest of the world uses the metric measurement system. One cup of water contains eight ounces. Liquid measuring cups are made of either plastic or glass and have a handle that makes it easy to pour the water into pots and pans. The amount of liquid is labeled, usually in red, on the side of the measuring cup. One side of the measuring cup usually displays measurements in metric. In the metric system, 250 mL equals one cup of water."

Wow, Kelly sure packed a lot of factoids into that; some of them rather questionable. For instance, does the UK actually use "metrics"? Isn't that just a fancy word for "measurement"? And isn't an 8-ounce cup actually 237 ml? But we're not here to discuss that... we're here to point out Taylor's big boo-boo.

Oh, Kelly found some instructions somewhere to help newbie cooks with measurements, tips such as,

• "Place your measuring cup on a... flat surface"
• "Wait until the water has settled."
• "Read where the water is at eye level instead of looking down"

We won't argue a one of those tips. What we will argue is that Taylor apparently wasn't aware of a little thing called a "meniscus." If you want your liquid measurements accurate (and Kelly apparently doesn't, since her cups-to-milliliters conversion is off by about 6 percent), you must pay attention to the meniscus.

For an accurate measurement of water in a glass measuring cup, you must look past where the edge of the water climbs on the glass and eyeball the flat surface in the middle (see image above). The meniscus effect becomes more pronounced as the diameter of the measuring vessel decreases. Kelly made the assumption that the question was asked by someone learning to cook, but it's perhaps more likely that the question was about elementary chemistry class. Taylor never mentioned the meniscus effect (probably because she wasn't aware of it), which renders her post eminently eligible for a Dumbass of the Day award. Go, Kelly.

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