SPOILERS The Long Cosmos **SPOILERS**

[Tonyblack]

I must admit that I hadn't really given the thought of metallic iron compared to iron as a chemical element. I've reread the Long books only once compared to the Discworld books, dozens of times - so I guess that one bypassed me.

 

[raisindot]

I sure don't remember that explanation from any of the series books, but I'll take your word from it it was somewhere. It still makes no sense to me. You can move gold, copper, bronze, uranium, titanium, plutonium, cobalt, and lead from one "world" to another in metal form, but not iron? It makes no scientific sense.

Even the "body iron" doesn't pass but metallic iron does pass argument makes no sense from a scientific point of view. Assuming that "moving" from one world to another is occurring at the atomic level, why would another "world" care whether a particular iron atom is bound up in an anvil or in the blood?

 

[Tonyblack]

Oddly enough, I think the whole iron plot was pure Pratchett rather than Baxter. It's a theme that is sprinkled through the Discworld books, especially in reference to the elves. I never really understood how Tiffany was able to take a frying pan into the land of the elves.

 

[raisindot]

I agree. It doesn't make sense scientifically. But, from a narrative point of view it kind of makes sense. If people are moving from one world to another and essentially building societies from the ground up, one of the first things they'd need to be able to do is forge iron. Excluding iron from the "passage" forces people to embrace old-timey professionals like blacksmiths, since so many tools and materials needed for building, farming and defense are made from iron.

 

[Dotsie]

Maybe it’s the ‘love of iron’ that prevents travel, so nothing magnetic can go.

Tiffany’s frying pan was aluminium, obviously