[Proj] Bessel's paper on geodesics; Cassini-Soldner projection

Charles Karney ckarney at sarnoff.com
Fri Aug 14 06:01:51 EST 2009

(1) Rod Deakin of RMIT and I have translated Bessel's paper on

    F. W. Bessel, Astron. Nachr. 4 (86), 241-254 (1826).

and posted the result at


(2) My library of geographic routines


now includes a C++ class for the Cassini-Soldner projection, a
transverse cylindrical equidistant projection.  This and the azimuthal
equidistant projection are defined in terms of the Geodesic class and
will given accurate (error 10 nm to 20 nm) results for the whole earth.
The projection routines also return the scale in the non-equidistant
direction which is computed in terms of the reduced length of the

I include a small utility program EquidistantTest to provide a interface
to these projections.

Charles Karney <ckarney at sarnoff.com>
Sarnoff Corporation, Princeton, NJ 08543-5300

Tel: +1 609 734 2312
Fax: +1 609 734 2662

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