WHEN IS A GALLON NOT A GALLON?….I see that Dennis Kucinich is busy tackling one of the nation’s most urgent problems: the fact that gasoline expands in hot weather. Thus the gallon of gasoline you buy in summer might not be a full gallon. It might only be 99.5% of a gallon.

That’s not really much of a difference. And anyway, in winter you’re probably getting 100.5% of a gallon. But it’s not winter right now, is it? It’s summer. And Kucinich apparently thinks the way to fix this miscarriage of justice is to require gas stations to install temperature-compensating meters on their pumps at a cost of about $2,000 a pop. That way we’ll get 100% of a gallon all year round.

I have two reactions to this. The first comes from Michael O’Hare, who correctly points out that none of this matters. If the meters do their job and gas stations take a 0.5% hit on revenues, they won’t just eat it. After a short while their prices will increase 0.5% and we’ll be right back where we started. Sometimes Economics 101 really is all you need in order to figure out that something is just plain dumb.

That really ought to be my only reaction, but I can’t help myself. I have to add this. It turns out that oil companies, which are fighting Kucinich’s proposal, have a rather different attitude toward temperature-compensating pumps in more northern climes:

Retail pumps in this country don’t have that capability. But the devices are widely used in Canada, where the temperature equation works in favor of consumers instead of fuel retailers — and where the oil industry pushed for the right to add the equipment.

It might be economically useless, but it’s hard not to figure that what’s good for the Canadian goose is also good for the American gander. I’m still opposed to Kucinich’s proposal on grounds of general dumbness, but I have to admit that there would be a wee bit of cosmic justice involved if it passed.