Cave exploration, or pot-holing, as it has come to be known, is a relatively new sport. Perhaps it is the desire for solitude or the chance of making an unexpected discovery that lures people down to the depths of the earth.
    洞穴勘探，或者洞穴探险，正如已逐渐被人了解的那样，是一项比较新的运动。也许正是对独处的渴望和对未知探险的机会，吸引着人们深入地心当中。
    PS: it is … that, 强调句
    PS++: down to the depths of the earths, 深入地心

    It is impossible to give a satisfactory explanation for a pot-holer’s motives. For him, caves have the same peculiar fascination which high mountains have for the climber. They arouse instincts which can only be dimly understood.
    对这些人的探险动机，众口难调。洞穴之于他们，就好像高山之于登山者。人们对此也只是有个懵懂的认知。
    PS: It is impossible to give a satisfactory explanation for, 很难有一个令人满意的解释，众口难调

    Exploring really deep caves is not a task for the Sunday afternoon rambler. Such undertakings require the precise planning and foresight of military operations. It can take as long as eight days to rig up rope ladders and to establish supply bases before a descent can be made into a very deep cave. Precautions of this sort are necessary, for it is impossible to foretell the exact nature of the difficulties which will confront the pot-holer.
    探索非常深的洞穴绝非周末散步的人能办到的。这种活动需要有军事级别的预判和精确计划。当然也需要长达8天的时间，搭起绳梯、建立供应基地、然后才能下到一个很深的洞穴里。在这种活动中，预防措施都是非常必要的，因为摆在探洞者面前的困难，是不可能被精准预测的。
    PS: supply base, 供应基地
    PS++: foretell the exact nature of the difficulties, 精准地预测困难

    The deepest known cave in the world is the Gouffre Berger near Grenoble. It extends to a depth of 3723 feet. This immense chasm has been formed by an underground stream which has tunnelled a course through a flaw in the rocks.
    世界上已知最深的洞穴是格勒诺布尔附近的高弗·伯杰洞，深达3723英尺。这条深邃的洞穴是由一条地下暗流冲刷岩石中的缝隙并使之慢慢变大而形成的。

    The entrance to the cave is on a plateau in the Dauphine Alps. As it is only six feet across, it is barely noticeable. The cave might never have been discovered had not the entrance been spotted by the distinguished French pot-holer, Berger. Since its discovery, it has become a sort of pot-holer’s Everest. Though a number of descents have been made, much of it still remains to be explored.
    洞穴的入口在丹芬阿尔卑斯山的高原上，因为只有六英尺宽，所以几乎不会被发现。若不是法国知名探洞者伯杰在一次偶然的机会中发现这个洞的话，它将永不为人所知。正是因为这个发现，它成了探洞者们的珠穆朗玛峰。虽然人们已经探索了相当一部分深度，但是总有更多的东西有待勘探。
    PS: might never have been discovered, 虚拟语气，本该被发现（但没有）

    A team of pot-holers recently went down the Gouffre Berger. After entering the narrow gap on the plateau, they climbed down the steep sides of the cave until they came to a narrow corridor. They had to edge their way along this, sometimes wading across shallow streams, or swimming across deep pools.
    最近有一个探洞队下到了高弗·伯杰洞。在从高原的狭窄入口进洞之后，他们顺着陡峭的洞壁往下爬，来到了一条狭窄的走廊上。他们不得不侧着身子往前走，有时淌过浅溪，有时游过深潭。
    PS: edge their way, 侧过身子

    Suddenly they came to a waterfall which dropped into an underground lake at the bottom of the cave. They plunged into the lake, and after loading their gear on an inflatable rubber dinghy, let the current carry them to the other side. To protect themselves from the icy water, they had to wear special rubber suits. At the far end of the lake, they came to huge piles of rubble which had been washed up by the water.
    突然，他们在洞底看到一条直落地下湖的瀑布。他们跳入湖中，把各种器具装上一条橡皮艇，顺着水流将他们飘到对岸。湖水冰冷刺骨，为了保暖，他们都要穿特制的橡皮衣服。在湖的尽头，他们见到一大堆由湖水冲刷上岸的碎石。
    PS: plunge into, 一头扎进…

    In this part of the cave, they could hear an insistent booming sound which they found was caused by a small waterspout shooting down into a pool from the roof of the cave. Squeezing through a cleft in the rocks, the pot-holers arrived at an enormous cavern, the size of a huge concert hall.
    在这儿，他们能听到持续不断的轰鸣声。后来他们发现这是由山洞顶部的一个小孔里喷出的水柱跌落到水潭中时发出的声音。探洞者们从岩石缝里钻过去，到达了一个巨大的洞里，其大小相当于一个大型音乐厅。

    After switching on powerful arc lights, they saw great stalagmites — some of them over forty feet high — rising up like tree-trunks to meet the stalactive suspended from the roof. Round about, piles of limestone glistened in all the colours of the rainbow. In the eerie silence of the cavern, the only sound that could be heard was made by water which dripped continuously from the high dome above them.
    他们打开强力聚光灯，看到了一株株巨大的石笋 — 部分石笋高度超过40英尺 — 像树干似地向上生长，最终碰到了悬挂在洞顶上的钟乳石。环顾四周，一堆堆大理石像彩虹一样闪闪发光。洞内有一种可怕的寂静，唯一可以听见的声音是高高的圆顶上不间断滴水的滴答声。
    PS: glistened in all the colours of the rainbow, 像彩虹一样闪闪发光
    PS++: eerie silence, 可怕的寂静