Some nomograms (for sundials) use a logarithmic portrayal because the
nomogram is often an additive device, and multiplication is done by adding
logarithms. However, some nomograms use division directly (
N or Z) and some
use multiplication directly (
circular), so, there is variety. Here are several types:-

type 1      | | |        additive nomogram     C = L + R    must use logs for * and /
type 2     | \ |        dividing nomogram     C = L / R     no logs for division
type 3     (   )       multiplying nomogram C = L * R    no logs for multiplying
type 4      \ /_       adds reciprocals         1/C = 1/L + 1/R

Further, the DeltaCAD macro:  
nomogram.bas   builds vertical and horizontal
dials, but since DeltaCAD (as I have it) only does natural logs as opposed to
base 10, these macros use Napierian logs. I also have PASCAL code for
nomogram generation, using the Lazarus IDE.
All nomogram files in one ZIP file,
DeltaCAD macro, and the
Lazarus/Pascal source and
executable, test skeleton programs,
and more.
see pages 81 et seq of the free
Supplemental Shadows
type 3
type 2
type 1
DeltaCAD macro is a complete v and h dial, a sunrise/set, a polar/meridian
dial with calendar data nomogram (both the three vertical line as well as the N
or Z nomogram), and a vertical decliners SD, SH, and DL with the v-dec hour
lines worked using SH and DL. The DL macro choice has two variations, the
second showing the use of differing line separations (xL, xC, xR) and the
modulus (scale) of the right line (mR) which you may change. Also has the
analemmatic dial nomogram. Does nomograms type 1,2, and 3.

Lazarus/Pascal code for the h, v, m/p, v-dec dials, and sunrise/set times all in
one ZIP file. Does nomograms type 1, 2, and 3. In essence, everything the
DeltaCAD macro does
except exporting the images, which needs a screen
screen capture program, I use PhotoMax Pro).

Printed nomograms from both DeltaCAD and Lazarus/Pascal are in PDF form.
This book of printed nomograms may be lower quality print than if you run the
DeltaCAD or the Lazarus based program, which you are encouraged to do.
appendices however have very high quality nomograms.

Documents online for nomogram design are:-

The Art of The Nomogram - read this first
Graphical and Mechanical Computation   
Creating nomograms with pynomo software  
JAVA online nomogram builder
A nomogram that is not type 1, 2, nor 3.
This is a quadrant of an equatorial dial.
Not really a nomogram, more a
teaching aid for correctly
some h-dial (and v-dial) hour lines
from an equatorial dial.
NOMOGRAMS ~ how to use as well as how to build them
~ nomograms for sundials [nomogramExamples.pdf]

~ how to build a nomogram for other purposes [page 81 et seq of
Supplemental Shadows]
Printed nomograms are here (pdf)