The Pilum – Did Legionaries Carry One or Two?

I used to be a museum guide, and when showing people the mannequins dressed as Romans, I used to tell the visitors that legionaries carried two pila, as I had seen it pictured in modern books. I may have been wrong.

The pilum (plural 'pila') was the standard throwing weapon of the Roman legions. Archaeologists has found weighted and unweighted versions of them, but were both types carried by every legionary?

The spark for this video was a discussion I had about the authenticity of a set of plastic model legionaries on the march. They were shown carrying one pilum and wearing lorica segmentata. I said that they should have two, but then found myself unable to back this up with evidence. Polybius, writing about the earlier period, with javelin-throwing velites, and the triarii at the back, says that the hastatii carried two types of pilum, but it isn't perfectly clear whether he meant that the unit carried both types, or each individual man within them. For the later days of the classic legionary, with no velites in front of him, and lorica segmentata on his back, I have no evidence for two pila per man.