Book IV chapter 14

On the variation under the æquinoctial line, and near it.

I n the North the magnetick needle varies because of the Boreal eminences¹ of the continent; in the South because of the Austral; at the æquator, if the regions on both sides were equal, there would be no variation. But because this rarely happens some variation is often observed under the æquator; and even at some distance from the æquator of three or 4 degrees toward the North, there may be a variation arising from the south, if those very wide and influential² southern continents be somewhat near on one side.

1 eminences   

卓越( eminence的名词复数 )； 著名； 高地； 山丘

参考例句：

• Both are truly grey eminences who have become accustomed to the exercise of influence. 两个人都是真正的幕后操纵者，他们已习惯于用其影响进行幕后操纵。

2 influential   

adj.有影响的，有权势的

参考例句：

• He always tries to get in with the most influential people.他总是试图巴结最有影响的人物。
• He is a very influential man in the government.他在政府中是个很有影响的人物。