Reading a Barometer for Dummies

Aneroid barometer used as altimeter

As a wise old sage (probably our founder) once said, "Even a blind pig finds the occasional acorn." Heck, there's a plaque in the break room at Antisocial Network HQ (on the wall above our Gaggia espresso maker) with that saying: it means, more or less, that even idiots get things right once in a while. That's definitely the case with eHow contributors, self-appointed freelancers like "communications graduate" Alexis Writing, whom our researchers found declaiming about "The Uses of Barometers," now (for no known reason) on Leaf Group's Hunker.com.¹ In Alexis' case, the blind pig was able to produce a list of uses, but the presentation left it obvious that she had no earthly idea what she was saying...

Take, for instance, her DMS-mandated introduction (75-100 words): this masterpiece of information blithely tells her readers that,

"Barometers are meteorological devices that incorporate vacuum pressure to measure the pressure of outside air. These devices have a long history of use dating back to the early 17th century, and for hundreds of years prior to that scientists throughout Europe were investigating ways that the barometer could be used to determine a number of different things about the air and the world."

We spotted some problems in just those two sentences:

• Barometers, as Alexis herself points out within the text, are not necessarily "meteorological devices."
• Only aneroid barometers use vacuum pressure.
• We're curious: how did scientists use barometers for "hundreds of years prior" to their invention? 
• The only barometer Writing mentions in her content is the aneroid barometer, which was invented in the 19th century, not the 17th. Oops...

Alexis then lists several instruments for measuring pressure, usually barometric, and mentions their use: "Barometers have long been used for measuring weather patterns. Air pressure from high and low pressure fronts that move throughout the globe is useful in determining or predicting what the weather will be like at a given time and on a given date. This is the most basic and historical use for barometers, and these devices help determine whether it will be hot or cold..." We found the construction "determining... what the weather will be like... on a given date" to be rather misleading, as is the suggestion that barometers measure temperature. Writing's grasp of the use of barometers in weather forecasting appears to be, at best, rather tenuous. Alexis also mentions the use of (aneroid) barometers in air travel, where airspeed is measured with a pitot tube:

"Other types of barometers include air pressure reading devices that report the air speed of an aircraft. Often called pitot tubes, these devices are a type of barometer that senses the pressure of air moving against an aircraft and then converts this reading into an estimated air speed indicator, allowing pilots to determine how fast they are moving relative to the air around them."

While pitot tubes are, indeed, used for airspeed indicators, they can be used to measure the speed of flow of any fluid. More to the point, Alexis' claim that a pitot tube "senses the pressure of air moving against an aircraft" is clearly bogus: pitot tubes don't "sense the pressure," they measure pressure differential at two points; apparently an explanation too complex for someone who skipped science classes because they were "hard."

Nope, this particular blind pig managed to find some acorns with her research, but that doesn't mean she accomplished her task. Her facts are questionable, her explanations are simplistic or simply wrong, and her grasp of the science is beneath poor. We have no choice but to give Alexis another Dumbass of the Day award. It's the third for this person, who -- we suspect -- is so ashamed of her (his?) dumbassery s/he uses a nom de plume...

¹ The original has been deleted by Leaf Group, but can still be accessed using the Wayback machine at archive.org. Its URL was   ehow.com/info_8072198_uses-barometers.html

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