Kindle or tablet? Silly question

I’ve been involved in a few debates recently over why people need a Kindle when they have an iPad or other Kindle-enabled tablet.

It’s a ridiculous argument, in my view. For two reasons.

First, battery life.

My Kindle stays charged for weeks. Literally. I’ll probably charge mine every three weeks or so, more to top it up than necessarily because it’s running low on juice. This is of massive appeal. I can pop it in my bag, just as I would a book, and forget about it until such time that I choose to read it. If I had to take it out of my bag each night to charge it, something would be lost. Something very important.

Second, and more importantly, experience.

When I read my Kindle, I’m reading a book. It’s the size of a book, and the utterly delightful E Ink technology makes it feel like a book. A beautiful, imperfect book, even with slight “printing” flaws owing to the technology.

When reading on a tablet, I’m reading a magazine. Even when the screen’s brightness is set low, the experience is completely different to that of the Kindle. It’s backlit, and that fundamentally changes the reading experience. My eyes are working, not dancing. I’m no doctor, but I expect that their state while reading a Kindle is very different to that when they’re reading a tablet.

And that’s why for now, there’s absolutely a place for the Kindle in your bag, even if you’ve got a tablet.

(Note: I don’t own a tablet. But I’ve borrowed them, from the likes of my daughter.)

Reuleaux polygons and tetrahedra

My friend Rob sent me this video today. I just watched it. And I loved it. Here’s the background.

Certain 2D shapes are such that their height is the same regardless of their orientation on the plane. The obvious example is the circle, meaning that your bicycle runs smoothly down the road.

But there are an infinite number of other shapes that share this quality. For the UK contingent amongst you, the 50p and 20p pieces are examples.

You see, they’re not quite heptagons. They’re actually Reuleaux heptagons. That means that where they might have straight edges, the edges are instead slightly curved. And the point on the coin that is opposite that curved side lies at the centre of the circle of which the curve is an arc.

To prove it, take a ledge (e.g. the bottom lip of a laptop screen, or the point at which a radiator guard meets the wall). Place two 50p pieces upright on the ledge. And grab a ruler. Place the ruler across the top of the two coins and drag the coins left or right. You’ll find that the ruler remains the same distance from the ledge at all times.

Simply delightful. And yet more so when you discover that there are Reuleaux triangles!

Now you couldn’t make a bicycle using these shapes, as the centre moves around as the coin rolls. So while the highest point of the wheel would remain a fixed distance from the ground, the point of the axle would wobble go up and down relative to the ground, and so the ride would be a little bumpy.

Now, it gets better. As well as there being an infinite number of Reuleaux planes, there are also an infinite number of Reuleaux solids, which share similar properties. So you can balance a board on a bunch of them, roll it around, and the board will remain a fixed distance from the floor.

You can buy a bag of them here. *reaches for credit card*

(Oh. I also love the guy’s enthusiasm for the subject.)

The black hole of online car tax renewal

So. My car tax is due to expire on 30 November.

The trouble is, my insurance is due to expire on 26 November.

I am able to renew my car tax any time after 5 November, and received a letter to this effect from the DVLA on 5 November. So I went online to renew the following day.

The site said that I couldn’t renew online, as the motor insurance database did not have proof of my having insurance beyond the point of the car tax renewing. Apparently, I’m unable to renew my car tax within the last three weeks of my insurance policy. Coincidentally, that means I’m unable to renew my car tax after 5 November.

So I went through the process of renewing my insurance, with Privilege, and they have now confirmed that on 26 November, my insurance will renew with them for another year.

The trouble is, they are unable to inform the DVLA of my new insurance policy until my existing policy is at the point of expiry.

So I will instead need to go into a Post Office to renew my car tax; or else I need to try to do it in the four-day window between 26 and 30 November. And here’s the rub: the proximity of the two expiry dates means that this will be an annual “feature” of my relationship with the DVLA, unless I choose to pay an £11 premium to only renew my car tax for six months.

Utter madness.