谈墨卡托投影图的图长单位及现用的“渐长率”名词

The Length Units in the Mercator Projection Chart and the Present Chinese Term for“Miridional Parts”

本文论述了墨卡托投影图的图长单位。指出，墨卡托投影图的图长单位不是“赤道海里”，而是图上１’经度的图长，以澄清目前存在的一些误解。笔者还对现用的“渐长率”名词的合理性谈了自己的看法。并建议用“子午线渐长率”代替现用名词，以减少不必要的误解。

This paper discusscs the length units in the Mercator Pro-jection Chart.It is pointed out that the units are not the“quatorial nauti-cal miles”,but rather the longitude units of 1’in the chart.Furthermore,the paper expresses a critical view on the prcsent Chinese term for‘meridi-onal parts”,and suggests a new one that can clear up some misunderstand-ing。