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chart scale information on charts...


Subject: chart scale information on charts...
From: Russell Sher (rsher@XXX.XXX)
Date: Tue Apr 04 2000 - 09:51:40 EDT


I have a small question about the chart scale as displayed on mercator
charts:
Normally the scale on the chart is displayed as that scale given according
to a particular latitude for example
1: 750 000 (at 34 deg 00' S), thus implying that the scale is calculated for
the length of latitude at the given value (in this case 34 deg 00').
My question is - Is the scale stated in this way due to the mercator
distortion as one travels away from the equator (due to the nature of the
projection), or is the scale stated in this way due to the (slight) change
in the value of a minute of latitude due to the oblate shape of the earth?

Regards
Russell





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