Thanks, I'll check it out.
I used to be put off from the altitude dials by the noon inaccuracy. I was
concerned that Romans must have sometimes been late to noon appointments
and lunch-dates.
But I'd expect that, where lots of people are using altitude dials,
punctuality-critical events and
When I said that there isn't an obvious way to measure to make the
plumb-line length equal to sec lat sec dec, I meant that there' s no
obvious way to achieve that *with one measurement*.
I was looking for a way to do it with one measurement, because that's how
the use-instructions say to do it.
