[Proj] Re: Discovery: libproj4 stmerc = French Gauss-Laborde projection

Gerald I. Evenden gerald.evenden at verizon.net
Wed Jun 14 11:42:40 EDT 2006

On Wednesday 14 June 2006 1:12 am, Strebe at aol.com wrote:
> You might contact Dr. David E. Wallis. He devised a much simpler method
> than Dozier's. I've implemented it for the full-ellipsoid. You can see a
> plot of an earth-like ellipsoid here:
> http://mapthematics.com/Projection%20Images/Cylindrical/Transverse%20Mercat
>or. GIF
> The method works for arbitrary eccentricities. Contact me privately if
> you're interested. Since it is Dr. Wallis's invention, I'll put you in
> contact with him.

Dr. Wells has a web page relating to the projection:


that a Google search on his name will return.  Found this site several years 
ago during a previous discussion about tmerc.  To me, the web page appears 
unchanged and the "Publication Pending" notice at the top is certainly taking 
a long time.

I should post him a letter for further information and follow up with a phone 
call if no response.

The description of the equation present does not make much sense unless what 
looks like p in the tan term is not the p described as colatitude.  Again, 
the first line says p,lambda is the colatitude and longitude yet the 
description following the formula talks about a p for the Elliptic Integral 
of the second kind.

I must be missing something.

Jerry and the low-riders: Daisy Mae and Joshua
"Cogito cogito ergo cogito sum"
   Ambrose Bierce, The Devil's Dictionary

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