28 June 2006
SETI League
PriUPS Project

What Kind of Foot Are You?

Are you a leadfoot?  I'm not and never was, although I wasn't entirely innocent of speeding.  I could have been an arsenic foot or maybe a radium foot (each about half the density of lead, although, paradoxically much more deadly in the elemental realm than in that of velocity).  Before I got my Prius I would drive pretty much like everyone else just slow enough to be unlikely to get a ticket.  A bit aggressive, a bit cranky, not unduly polite.  As it says in my contact information, "Be careful!  I drive like you do."

Why has this changed?  Why do I drive at exactly the speed limit during most of my commute, and slightly below it in one segment?    And no, It's not the cruel type of driving engaged in by the evil schnurgs who go excessively slowly in the left lane, or deliberately try to slow others down.  I'm a good vehicular citizen.  I change lanes to allow others to enter the highway.  I make a space, if I can do so without using my brakes, to let others change lanes.  I don't curse other drivers, no matter how benighted they may be.  I'm slow, tedious, and inoffensive.  What is there about the Prius that has engendered this (admittedly modest, in my case) change in the behavior of an American male driver? 

I think that I've decided that the answer is "for entertainment."  I could easily get away with a small lie here and assert it's "to save gas."  In fact, my driving style is precisely that required to use a minimal amount of gasoline.  By not using brakes and being careful with stored energy, both potential and kinetic, I routinely get the EPA mileage specified for the Prius, and occasionally better it.  But I'm a reasonably honest person, occasionally even with myself, and I have to admit that a gas mileage obsession isn't of any great value, either to me or to the surrounding world.  But unlike Jodie, I've found that trying my luck with the traffic police out of boredom more than spite* doesn't have the entertainment value of watching the glowing LCD display and urging that average MPG figure ever higher.

What are the trades-off?  It costs me a little time.  One minute and thirty seconds on average, as it happens, to trade arsenic for scandium:

Foot Element Density Time Saving per trip/year Anxiety Level Tickets/Year
Osmium 22.6 g/cm3 4.5 minutes/45 hours Ultra Many
Lead 11.35 g/cm3 3 minutes/30 hours Modest+ One or two
Arsenic 5.72 g/cm3 1.5 minutes/15 hours A bit Usually none
Scandium 2.99 g/cm3 None None None
Hydrogen 1.0079 g/cm3 Negative None, if awake One or two

The hypothetical "Time Saving" is based on my driving schedule; for others it will obviously vary.  I suppose it's also obvious that saving 45 hours per year isn't as valuable as it may seem, given that it's being saved it in tiny increments and evil Osmium Foot at least will be too shagged out after arriving to do more than try to relax for the saved time.  

So what about the entertainment, then?  In addition to the normal complement of displays and gauges, I have an Argus aircraft navigation display in the car.  That's what allows me to time traffic lights since it displays GPS time as well as navigation data.  It also provides altitude, which is otherwise unavailable from the Prius.  When I commute, I'm continually switching and monitoring all the displays and readouts.  And, of course, obsessing unnecessarily over the MPG display.  Fortunately I have sufficient mental bandwidth left over to find my way to work, even with the help of the moving maps.  I turn up the music, watch the glowing instruments, and at my legal speed, don't worry at all about the traffic police.  A pleasant commute!  I can't help wondering if people would drive less aggressively if someone offered a dashboard-mount lava lamp.

Not being a car manufacturer, I feel no compulsion to add the standard "drive responsibly and don't speed."  Although there is little doubt that accidents at higher speed are more likely to damage protoplasmic participants, that doesn't mean that speeding is necessarily going to cause an accident.  As has long been obvious, and has been confirmed by a very recent study, the most important thing is to pay attention!

*Thank you, Lloyd Cole.  Rattlesnakes is a great song!

Richard Factor