Where did this word come from, and why is it the same word as we use to talk about the amount of stuff that a container will hold?

It came as a bit of a surprise to me, but The Oxford English Dictionary tells me that the earliest meaning of “volume” is the booky one. It all goes back before the invention of the codex. “Volvere” is the Latin verb meaning roll, twist, and thus “volumen” meant a coil, a wreath or a roll — which obviously lands us with a scroll on our hands. Now in those days Latin had great authority, as the lingua franca across Europe which English has now become (in succession to French). It may thus seem a bit paradoxical that the earliest recorded use of the word “volume” in English (by a year or two only) refers actually to a codex, not a scroll — but the paradox is only apparent: by 1380 the scroll had of course long been superseded by the codex.

So how did the word get to be used to describe the amount of material that’ll fit in a container? Apparently, rather unexpectedly, via the book: it was apparently first used in its quantity sense to describe the amount of stuff in a book, as in “The Alcoran or Bible . . . is in volume twice so big as the Psalmes of David..” It was only in the eighteenth century that “volume” began to appear in the sense I’d assumed was primary: “The prodigious volumes of water which have from the beginning of the world been falling into [the ocean].”

I guess it’s fairly clear how it’d move over, around the same time, to mean the loudness of music. Who’d have guessed that it also meant a bend in a stream, as in: “Where Thames’s fruitful Tides, Slow thro’ the Vale in silver Volumes play”?

Oddly perhaps, we’d buy paper by the carload, which masquerades as a volume measurement. Carload was “defined” as the amount that would fit in a railroad car — but that was always figured to be 40,000lbs, so we were really buying by weight not volume.