In reply to:

Given that the first string is normally the bottom string in the normal dextrocentric manner of holding the instrument

This brings up a point of contention. As a musician, I call the strings whose notes are the lowest on the scale (the bass notes) the "low strings" or the "bottom strings." But the "first string" is the highest (note) string. And I feel that I am in the majority, but I occasionally encounter a guitar player, etc who refers to those strings that are physically lower to the ground as the "low strings" or "bottom strings." Is there any regional trend to this or what?