Some hikers think it’s stupid to bring a book on a long hike. You’re there to connect with nature, they say. Once you’ve set up camp, you should observe, feel, and relate with the wonders around you.

I can’t argue with that. But I like to read, and reading in the sun by the side of a mountain lake is, for me, as good as it gets.

These hikers also point out, with more justice, that the damn things are heavy. Aren’t we all ultralight hikers now?

So the whole thing comes down to an unfamiliar literary calculus: reading value per ounce. Good books that are too heavy are out, as are less than good books at any weight.

But sometimes a heavier book can save your life. When caught by a sleet storm up near the divide in Jasper and forced to hole up for twenty four hours, I read Neil Stephenson’s Cryptonomicon and didn’t even notice the hours go by. At home, I’d had trouble with the book partway through (I had young kids at the time, and thus a reduced attention span—and the man could sure use a more assertive editor), but confined to a tent with nothing but sodden morrass outside, I followed the escape from New Guinea with total attention. A bit heavy and bulky, but that time it was the right choice.

On another Canadian Rockies hike I’d hauled Bed Gadd’s magnificent Handbook of the Canadian Rockies. Make no mistake, this is one of the best guide books to a wilderness area you’re going to find. But the thing is printed on coated paper and weighs over two pounds. That was just a symptom of greater overloading, and I was miserable that whole hike.

I read Stephen Jay Gould’s Panda’s Thumb in Dark Canyon, and Orwell’s essays in Bandelier.

I’m just back from the Sawtooths, where, after some internal debate (15 oz!) I brought Dorothy Dunnett’s Niccolo Rising, and didn’t regret it for a moment.

I presume the Kindle and its descendants will eliminate this entire critical metric—you can carry hundreds of books weighing only a few ounces. I won’t be able to resist for long.