Arms control

The twelfth entry is il protocollo aggiuntivo, and the first of its two words reached the language of treaties by way of a workshop. It is Greek prōtokollon, built from prōtos, first, and kolla, glue: the sheet pasted to the front of a papyrus roll, carrying the note of when the roll was made and by whom. Whatever stood on that leaf authenticated everything behind it, and that is how a term for a piece of stationery came to mean an official record, then the minutes of a meeting, then a signed instrument attached to an agreement — which is precisely what il protocollo aggiuntivo is, a document glued, in effect, to the front of another. English carries the same kolla in two places where nobody hears it: « collagen » is the substance that yields glue when boiled, and a « colloid » is a mixture that behaves like one. So an inspection instrument and a pot of glue share a root, and the word says what the thing does: it is fixed to the treaty and cannot be read apart from it.