four lines on a spirit level

[Dave]

I'm sorry, I can't get to the bottom of this and as I don't have a four line spirit level atm, I can't check out my theory.

Dave

[Dave]

If I can, I'll get back to you, even if it will be too late for you.

Dave

[spamlet]

Why not ask them:

't see any with four lines - but they do offer a design service...

And these can have lots of lines! (when perhaps they get renamed clinometers...:

[dom]

Everything you need to know is on that site - bubble sensitivity is typically 2mm horizontal movement for half a degree tilt for the better ones, closer to a degree for the cheaper ones.

The same relationship will apply no matter how long a level the bubble is set in.

[Dave]

Sorry about this, I usually have enough contacts to ask this question.

Dave