mondrian:
I'll leave it for someone else to explain why exactly they burst
I'd assume it's because air expands as it gets warmer, and this expansion would raise the air pressure in the confined space of the tyre's inner tube. You're certainly meant to check and correct your tyre pressure if the weather turns very cold or hot, but I agree that you don't often hear of tyres going bang on a hot day these days. Maybe modern inner tubes are stronger, but maybe it still happens in really hot countries.
mct16:
Is such an incident feasible and, if not, what would have been a more logical, and dramatic, way to keep Tintin and the others from leaving?
I've never much thought about this, but actually I don't think it's just a slightly weak or undramatic plot device on the part of Hergé. Surely the sun - the Incas' deity - is the perfect thing to be "attacking" Haddock's car in this book. It may well have been an unlikely occurence even back in the 1940s, but if so that only adds to the subtle build up of weirdness in the Tarragon's house part of the book, with another freaky natural phenomenon to come in the shape of the ball lightning (another ball of fire).
Just thinking about all this reminds me how very good that book is. I'm going to have to re-read it tonight (for the hundredth time!)
Thanks for the nice anecote, Mondrian. I've read that Bill Bryson book, but had forgotten that bit. Another book to re-read sometime!