Need help with creating a nomograph in Excel

[Emmar01]

I need to crate an Excel model of a nomograph - picture three parallel vertical lines with different (non-linear values) on each. If done manually, by drawing a straight line between the values on the two outer lines and reading where it intercepts the middle line gives the reading I want. How can I model this in Excel?

<Sorry, my user status doesn't allow me to post images or else I would have>

 

[Fazza]

Maybe best to explain (specifically) how it is done on paper.

And then this can be used to set up something on a worksheet.

 

[Fazza]

or you can google & find solutions
such as http://www.projectrho.com/nomogram/3varaddB.html

this looks informative too,http://myreckonings.com/wordpress/wp-content/uploads/nomography.pdf
and there are many, many more, including youtube