On Sat, 30 Jun 2012 20:49:21 +1000, F Murtz wrote:

If the vertical has only one bubble unit it may or may not read upside down.

I've a 2m level where the vertical is only a couple of inches from one end -
my eye-level is about 1m 83 and I can't read the vial thing!
--
Peter.
The gods will stay away
whilst religions hold sway