Slipped the scheme to the minister privately, under plain cover!

私下把看似毫不起眼的计划塞给了大臣！

Arriving at the topmost ridge of this promontory, I could see vast white plains covered with walruses.

到了尖呷的高脊背上，我望见一片白色的广大平原，上面全是海马。

There was a general disappointment among the passengers, who, without reckoning the delay, saw themselves compelled to trudge fifteen miles over a plain covered with snow.

此外，所有的旅客也都感到很丧气，耽搁时间暂且不说，旅客还得在这冰天雪地里步行十五六英里。