Spherical Transverse Mercator
In constructing a map on any projection, a sphere is normally chosen to model the earth when the extent of the mapped region exceeds a few hundred kilometers in length in both dimensions. For maps of smaller regions, an ellipsoidal model must be chosen if greater accuracy is required; see next section. The spherical form of the transverse Mercator projection was one of the seven 'new' projections presented, in 1772, by Johann Heinrich Lambert (also available in a modern English translation) Lambert did not name his projections; the name transverse Mercator dates from the second half of the nineteenth century. The principal properties of the transverse projection are here presented in comparison with the properties of the normal projection.
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