Definition
Each parallel is developed on its own tangent cone, so parallels appear as non-concentric arcs and only the central meridian is straight and true to scale. It is neither conformal nor equal-area, but distortion is small within a narrow band either side of the central meridian, which suited long survey sheets. Historically standard for United States Coast and Geodetic Survey work, it has largely been superseded by Mercator and transverse Mercator for marine charting.
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