Cyrus Harding's project had succeeded, but, according to his usual habit he showed no satisfaction; with closed lips and a fixed look, he remained motionless. Herbert was in ecstasies, Neb bounded with joy, Pencroft nodded his great head, murmuring these words,--
"Come, our engineer gets on capitally!"
The nitro-glycerine had indeed acted powerfully. The opening which it had made was so large that the volume of water which escaped through this new outlet was at least treble that which before passed through the old one. The result was, that a short time after the operation the level of the lake would be lowered two feet, or more.
The settlers went to the Chimneys to take some pickaxes, iron-tipped spears, string made of fibers, flint and steel; they then returned to the plateau, Top accompanying them.
On the way the sailor could not help saying to the engineer,--
"Don't you think, captain, that by means of that charming liquid you have made, one could blow up the whole of our island?"
"Without any doubt, the island, continents, and the world itself," replied the engineer. "It is only a question of quantity."
"Then could you not use this nitro-glycerine for loading firearms?" asked the sailor.
"No, Pencroft; for it is too explosive a substance. But it would be easy to make some guncotton, or even ordinary powder, as we have azotic acid, saltpeter, sulphur, and coal. Unhappily, it is the guns which we have not got.
"Oh, captain," replied the sailor, "with a little determination--"
Pencroft had erased the word "impossible" from the dictionary of Lincoln Island.
The settlers, having arrived at Prospect Heights, went immediately towards that point of the lake near which was the old opening now uncovered. This outlet had now become practicable, since the water no longer rushed through it, and it would doubtless be easy to explore the interior.
In a few minutes the settlers had reached the lower point of the lake, and a glance showed them that the object had been attained.
In fact, in the side of the lake, and now above the surface of the water, appeared the long-looked-for opening. A narrow ridge, left bare by the retreat of the water, allowed them to approach it. This orifice was nearly twenty feet in width, but scarcely two in height. It was like the mouth of a drain at the edge of the pavement, and therefore did not offer an easy passage to the settlers; but Neb and Pencroft, taking their pickaxes, soon made it of a suitable height.
The engineer then approached, and found that the sides of the opening, in its upper part at least, had not a slope of more than from thirty to thirty-five degrees. It was therefore practicable, and, provided that the declivity did not increase, it would be easy to descend even to the level of the sea. If then, as was probable, some vast cavity existed in the interior of the granite, it might, perhaps, be of great use.
"Well, captain, what are we stopping for?" asked the sailor, impatient to enter the narrow passage. You see Top has got before us!"
"Very well," replied the engineer. "But we must see our way. Neb, go and cut some resinous branches."
Neb and Herbert ran to the edge of the lake, shaded with pines and other green trees, and soon returned with some branches, which they made into torches. The torches were lighted with flint and steel, and Cyrus Harding leading, the settlers ventured into the dark passage, which the overplus of the lake had formerly filled.
Contrary to what might have been supposed, the diameter of the passage increased as the explorers proceeded, so that they very soon were able to stand upright. The granite, worn by the water for an infinite time, was very slippery, and falls were to be dreaded. But the settlers were all attached to each other by a cord, as is frequently done in ascending mountains. Happily some projections of the granite, forming regular steps, made the descent less perilous. Drops, still hanging from the rocks, shone here and there under the light of the torches, and the explorers guessed that the sides were clothed with innumerable stalactites. The engineer examined this black granite. There was not a stratum, not a break in it. The mass was compact, and of an extremely close grain. The passage dated, then, from the very origin of the island. It was not the water which little by little had hollowed it. Pluto and not Neptune had bored it with his own hand, and on the wall traces of an eruptive work could be distinguished, which all the washing of the water had not been able totally to efface.
The settlers descended very slowly. They could not but feel a certain awe, in this venturing into these unknown depths, for the first time visited by human beings. They did not speak, but they thought; and the thought came to more than one, that some polypus or other gigantic cephalopod might inhabit the interior cavities, which were in communication with the sea. However, Top kept at the head of the little band, and they could rely on the sagacity of the dog, who would not fail to give the alarm if there was any need for it.
After having descended about a hundred feet, following a winding road, Harding who was walking on before, stopped, and his companions came up with him. The place where they had halted was wider, so as to form a cavern of moderate dimensions. Drops of water fell from the vault, but that did not prove that they oozed through the rock. They were simply the last traces left by the torrent which had so long thundered through this cavity, and the air there was pure though slightly damp, but producing no mephitic exhalation.
"Well, my dear Cyrus," said Gideon Spilett, "here is a very secure retreat, well hid in the depths of the rock, but it is, however, uninhabitable."
"Why uninhabitable?" asked the sailor.
"Because it is too small and too dark."
"Couldn't we enlarge it, hollow it out, make openings to let in light and air?" replied Pencroft, who now thought nothing impossible.
"Let us go on with our exploration," said Cyrus Harding. "Perhaps lower down, nature will have spared us this labor."
"We have only gone a third of the way," observed Herbert.
"Nearly a third," replied Harding, "for we have descended a hundred feet from the opening, and it is not impossible that a hundred feet farther down--"
"Where is Top?" asked Neb, interrupting his master.
They searched the cavern, but the dog was not there.
"Most likely he has gone on," said Pencroft.
"Let us join him," replied Harding.
The descent was continued. The engineer carefully observed all the deviations of the passage, and notwithstanding so many detours, he could easily have given an account of its general direction, which went towards the sea.
The settlers had gone some fifty feet farther, when their attention was attracted by distant sounds which came up from the depths. They stopped and listened. These sounds, carried through the passage as through an acoustic tube, came clearly to the ear.
"That is Top barking!" cried Herbert.
"Yes," replied Pencroft, "and our brave dog is barking furiously!"
"We have our iron-tipped spears," said Cyrus Harding. "Keep on your guard, and forward!"
"It is becoming more and more interesting," murmured Gideon Spilett in the sailor's ear, who nodded. Harding and his companions rushed to the help of their dog. Top's barking became more and more perceptible, and it seemed strangely fierce. Was he engaged in a struggle with some animal whose retreat he had disturbed? Without thinking of the danger to which they might be exposed, the explorers were now impelled by an irresistible curiosity, and in a few minutes, sixteen feet lower they rejoined Top.
There the passage ended in a vast and magnificent cavern.
Top was running backwards and forwards, barking furiously. Pencroft and Neb, waving their torches, threw the light into every crevice; and at the same time, Harding, Gideon Spilett, and Herbert, their spears raised, were ready for any emergency which might arise. The enormous cavern was empty. The settlers explored it in every direction. There was nothing there, not an animal, not a human being; and yet Top continued to bark. Neither caresses nor threats could make him be silent.
"There must be a place somewhere, by which the waters of the lake reached the sea," said the engineer.
"Of course," replied Pencroft, "and we must take care not to tumble into a hole."
"Go, Top, go!" cried Harding.
The dog, excited by his master's words, ran towards the extremity of the cavern, and there redoubled his barking.
They followed him, and by the light of the torches, perceived the mouth of a regular well in the granite. It was by this that the water escaped; and this time it was not an oblique and practicable passage, but a perpendicular well, into which it was impossible to venture.
The torches were held over the opening: nothing could be seen. Harding took a lighted branch, and threw it into the abyss. The blazing resin, whose illuminating power increased still more by the rapidity of its fall, lighted up the interior of the well, but yet nothing appeared. The flame then went out with a slight hiss, which showed that it had reached the water, that is to say, the level of the sea.
The engineer, calculating the time employed in its fall, was able to calculate the depth of the well, which was found to be about ninety feet.
The floor of the cavern must thus be situated ninety feet above the level of the sea.
"Here is our dwelling," said Cyrus Harding.
"But it was occupied by some creature," replied Gideon Spilett, whose curiosity was not yet satisfied.
"Well, the creature, amphibious or otherwise, has made off through this opening," replied the engineer, "and has left the place for us."
"Never mind," added the sailor, "I should like very much to be Top just for a quarter of an hour, for he doesn't bark for nothing!"
Cyrus Harding looked at his dog, and those of his companions who were near him might have heard him murmur these words,--
"Yes, I believe that Top knows more than we do about a great many things."
However, the wishes of the settlers were for the most part satisfied. Chance, aided by the marvelous sagacity of their leader, had done them great service. They had now at their disposal a vast cavern, the size of which could not be properly calculated by the feeble light of their torches, but it would certainly be easy to divide it into rooms, by means of brick partitions, or to use it, if not as a house, at least as a spacious apartment. The water which had left it could not return. The place was free.
Two difficulties remained; firstly, the possibility of lighting this excavation in the midst of solid rock; secondly, the necessity of rendering the means of access more easy. It was useless to think of lighting it from above, because of the enormous thickness of the granite which composed the ceiling; but perhaps the outer wall next the sea might be pierced. Cyrus Harding, during the descent, had roughly calculated its obliqueness, and consequently the length of the passage, and was therefore led to believe that the outer wall could not be very thick. If light was thus obtained, so would a means of access, for it would be as easy to pierce a door as windows, and to establish an exterior ladder.
Harding made known his ideas to his companions.
"Then, captain, let us set to work!" replied Pencroft. "I have my pickaxe, and I shall soon make my way through this wall. Where shall I strike?"
"Here," replied the engineer, showing the sturdy sailor a considerable recess in the side, which would much diminish the thickness.
Pencroft attacked the granite, and for half an hour, by the light of the torches, he made the splinters fly around him. Neb relieved him, then Spilett took Neb's place.
This work had lasted two hours, and they began to fear that at this spot the wall would not yield to the pickaxe, when at a last blow given by Gideon Spilett, the instrument, passing through the rock, fell outside.
"Hurrah! hurrah!" cried Pencroft.
The wall only measured there three feet in thickness.
Harding applied his eye to the aperture, which overlooked the ground from a height of eighty feet. Before him was extended the sea-coast, the islet, and beyond the open sea.
Floods of light entered by this hole, inundating the splendid cavern and producing a magic effect! On its left side it did not measure more than thirty feet in height and breadth, but on the right it was enormous, and its vaulted roof rose to a height of more than eighty feet.
In some places granite pillars, irregularly disposed, supported the vaulted roof, as those in the nave of a cathedral, here forming lateral piers, there elliptical arches, adorned with pointed moldings, losing themselves in dark bays, amid the fantastic arches of which glimpses could be caught in the shade, covered with a profusion of projections formed like so many pendants. This cavern was a picturesque mixture of all the styles of Byzantine, Roman, or Gothic architecture ever produced by the hand of man. And yet this was only the work of nature. She alone had hollowed this fairy Aihambra in a mass of granite.
The settlers were overwhelmed with admiration. Where they had only expected to find a narrow cavity, they had found a sort of marvelous palace, and Neb had taken off his hat, as if he had been transported into a temple!
Cries of admiration issued from every mouth. Hurrahs resounded, and the echo was repeated again and again till it died away in the dark naves.
"Ah, my friends!" exclaimed Cyrus Harding, "when we have lighted the interior of this place, and have arranged our rooms and storehouses in the left part, we shall still have this splendid cavern, which we will make our study and our museum!"
"And we will call it?--" asked Herbert.
"Granite House," replied Harding; a name which his companions again saluted with a cheer.
The torches were now almost consumed, and as they were obliged to return by the passage to reach the summit of the plateau, it was decided to put off the work necessary for the arrangement of their new dwelling till the next day.
Before departing, Cyrus Harding leaned once more over the dark well, which descended perpendicularly to the level of the sea. He listened attentively. No noise was heard, not even that of the water, which the undulations of the surge must sometimes agitate in its depths. A flaming branch was again thrown in. The sides of the well were lighted up for an instant, but as at the first time, nothing suspicious was seen.
If some marine monster had been surprised unawares by the retreat of the water, he would by this time have regained the sea by the subterranean passage, before the new opening had been offered to him.
Meanwhile, the engineer was standing motionless, his eyes fixed on the gulf, without uttering a word.
The sailor approached him, and touching his arm, "Captain!" said he.
"What do you want, my friend?" asked the engineer, as if he had returned from the land of dreams.
"The torches will soon go out."
"Forward!" replied Cyrus Harding.
The little band left the cavern and began to ascend through the dark passage. Top closed the rear, still growling every now and then. The ascent was painful enough. The settlers rested a few minutes in the upper grotto, which made a sort of landing-place halfway up the long granite staircase. Then they began to climb again.
Soon fresher air was felt. The drops of water, dried by evaporation, no longer sparkled on the walls. The flaring torches began to grow dim. The one which Neb carried went out, and if they did not wish to find their way in the dark, they must hasten.
This was done, and a little before four o'clock, at the moment when the sailor's torch went out in its turn, Cyrus Harding and his companions passed out of the passage.
赛勒斯·史密斯的计划成功了，但是他还和过去一样，没有满足的表示，他紧闭着嘴唇，眼睛睁得大大的，一动也不动地站着。赫伯特却高兴得几乎发了狂，纳布乐得手舞足蹈，潘克洛夫点着他的大脑袋，自言自语他说：
“好，我们的工程师真有办法！”
硝化甘油的确发挥了极大的威力。它所炸开的新出口非常大，流出来的水至少要比从旧道排出的多三倍。爆炸以后不久，湖面就会降低三英尺，也许还要多些。
居民们到“石窟”里去拿了几把鹤嘴锄和铁头标枪，还有一些纤维绳索、火石和钢块；然后回到高地上来，托普也跟着他们一起来了。
一路上水手忍不住对工程师说：
“你做的那种油实在好，用它能把我们的海岛全都炸毁，你说是不是，史密斯先生？”
“不用说海岛，连大陆、全世界都可以，”工程师答道。“只是数量多少的问题。”
“那么你能用硝化甘油来做弹药吗？”水手问道。
“不能，潘克洛夫；它太容易爆炸了。可是要做一些棉花火药，甚至是普通的火药都不算难，因为我们有硝酸、硝石、硫磺和炭，不幸的是我们没有枪。”
“啊，史密斯先生，”水手答道，“只要有决心就能办到……”
潘克洛夫已经把“难”字从林肯岛的字典上抹去了。
格兰特湖原有的出口现在已经露出来。居民们来到眺望岗上，立刻就向那里走去。这个出口已经没有湖水在流，现在可以走人了。肯定地说，他们可以毫不困难地察看洞内。
几分钟以后，居民们来到湖的南端，他们一眼就看出目的已经达到了。
果然，湖里露出了他们搜求了很久的洞口，现在这个洞口已经在水面上了。湖水下降以后，留下一道狭长的分水线，使他们可以走近洞口。这个洞口横宽约二十英尺，但是高度却几乎还不到两英尺。它的样子很象人行道边下水道的沟口，因此居民们要想进去很不容易。可是纳布和潘克洛夫抡起鹤嘴锄，很快就把洞口凿到一个合适的高度。
然后工程师走向前来，他发现洞里的坡道斜度最多也不过三十到三十五度，至少洞口一带是这样的，因此是可以通行的。如果往前走坡度不变陡，甚至一直向海面走下去都不困难。花岗石的内壁里很可能有巨大的石洞，如果真是这样，也许会有极大的用处的。
“怎么，史密斯先生，我们呆着干什么？”水手问道，他急于要到狭长的甬道里去。“你看，托普已经进去了！”
“很好，”工程师答道。“可是我们一定要看得见道路。纳布，去砍一些带树脂的枯树枝来。”
纳布和赫伯特跑到湖边去了。这一带长着许多松树和其他的苍翠树木，他们很快就带了一些树枝回来，做成火把。用火石和钢片把它们点着，于是赛勒斯·史密斯就带领着大家冒险进入原来灌满湖水的漆黑的甬道。
出乎他们的意料之外，探险家们愈往前走，甬道的直径也就愈大，走了一会工夫，他们能够站直身子了。这里的花岗石经过流水长年的冲洗，又湿又滑，走在上面随时都有摔跤的危险。于是居民们采用了爬山时常用的办法，用一根绳索把大家连起来。幸而有些花岗石向外凸出，形成天然的梯阶，这样往下走去就不至于摔跤了。在火把的照耀下，有许多水珠在石头上闪闪发光，探险家们估计石壁上可能垂着无数的钟乳石。工程师仔细察着了这黑色的花岗石。上面看不出地层，连一条缝也没有。石头是整体的，而且石纹非常细致。估计从有海岛的那一天起，就已经有这条甬道了。它并不是由流水逐渐冲出来的。一手造成这个石洞的不是尼普顿而是柏鲁图，石壁上还遗有熔岩的痕迹，长期的水流冲刷也没能把它们完全磨灭。
居民们往下走得很慢。这个石洞还是第一次有人来，谁也不知道它究竟有多深。他们冒险往深处走，不由得产生了一种无名的恐惧。他们谁都不说话，然而脑子里却不住地在想，而且想的还不止一件事。这个地洞通向大海，也许有水螅和其他巨大的头足类动物住在里面吧。好在托普在小队的前面走着，他们可以依靠它的机智。在紧要关头，它是决不会不发警报的。
他们沿着曲折的道路，大约走了一百英尺的光景。走在前面的史密斯站住了，他的伙伴们也到了他的跟前。他们站脚的地方很宽，这里是一个大小适中的山洞。顶上一滴一滴地往下掉水，然而大家很清楚，水不是从岩石里渗出来的。只不过是多少年来在石洞里奔腾而过的急流所剩下的一点残迹罢了。这里的空气虽然有些潮湿，然而却很新鲜，没有丝毫浊气。
“亲爱的赛勒斯，”吉丁·史佩莱说，“这个地方正在岩石的深处，藏身倒很安全，可是不能住人。”
“为什么不能住人？”水手问道。
“因为太小了，光线又暗。”
“我们不能把它扩大一些，凿得更深一点，再开几个窟窿透亮和通风吗？”潘克洛夫答道，他现在认为没有一件事情是办不到的。
“我们继续搜索吧，”赛勒斯·史密斯说。“也许再往下一些，大自然会让我们省下这番气力的。”
“我们才走了三分之一的路程。”赫伯特说。
“将近三分之一，”史密斯说，“我们才从洞口往下走了一百英尺，不可能一百英尺以下就……”
“托普上哪儿去了？”纳布打断了他主人的话问道。
他们在附近搜索了一会儿，可是托普并不在这里。
“它大概往前走了。”潘克洛夫说。
“我们跟上去吧。”史密斯说。
他们继续往下走去。工程师每到甬道拐弯的地方，就特另注意，虽然曲折很多，他还是能毫不困难地说出大概的方向。石洞是通向大海的。
居民们又走了五十英尺左右，忽然听见下面很远的地方有一种声音。他们停下来听了一会儿。甬道象一个传声筒似的送过一些声音来，听起来非常清楚。
“是托普在叫！”赫伯特喊道。
“就是它，”潘克洛夫说，“我们勇敢的狗在愤怒地叫呢！”
“我们有铁头的标枪，”赛勒斯·史密斯说。“提防着，向前进！”
“愈来愈奇怪了。”吉丁·史佩莱在水手的耳边悄悄地说，水手点点头。史密斯和他的伙伴们急忙奔去，准备帮助他们的狗，托普的叫声愈来愈清晰，它好象愤怒得出奇。是不是它侵犯了什么动物的窝，双方正在搏斗呢？探险家们在好奇心驱使下，连可能遇到的危险也不顾了。过了几分钟，他们又往下走了十六英尺，找到了托普。
甬道到头了。这里是一个宽敞而高大的石洞，托普来回乱跑，愤怒地狂叫着。潘克洛夫和纳布手里举着火把，把每一个缝隙都照亮了。这时候史密斯、吉丁、史佩莱和赫伯特拿着标枪，随时防备任何可能发生的紧急事故。宽大的石洞里空空如也，什么也没有。居民们到处都搜查遍了，里面没有任何东西，没有一只野兽，更没有一个人，然而托普还是继续在叫。抚摩也好，呵斥也好，都不能使它安静下来。
“湖水一定是在这里通过什么地方流到海里去的。”工程师说。
“当然，”潘克洛夫说，“大家可都要留神，不要掉到窟窿里去。”
“走，托普，走！”史密斯喊道。
托普被它的主人一喊，就激奋地跑到石洞的尽头去了，它在那里叫得更加起劲。
他们跟上前去，用火把一照，看见花岗石地面上有一个洞，简直就象一口正规的井。湖水就是通过它排出去的。这里面不是什么倾斜的、可以通行的甬道，而是一口直上直下的井，要想冒险下去是不可能的。
他们将火把凑到井口来：什么也看不见。史密斯把一根点着了的树枝在深渊里扔去。树枝火在迅速下坠的时候更加明亮，它照亮了井的内部，然而还是看不见任何东西。只听见嗤的一声，火灭了，说明树枝已经落在水里，也就是海面。
工程师根据树枝坠落的时间，算出井的深度大概在九十英尺左右。
因此，这里的地面一定在海拔九十英尺的地方。
“这就是我们的住所，”赛勒斯·史密斯说。
“可是这里有什么兽类住着呢。”吉丁·史佩莱说，他的好奇心还没有满足。
“不管是不是两栖动物，反正它已经从井里逃出去，”工程师答道，“把地方让给我们了。”
“不管怎么说，”水手说，“托普是从来也不无缘无故乱叫的！我真想变成托普，哪怕只是一刻钟也好。”
赛勒斯·史密斯看看他的狗，喃喃地说：
“是的，我相信托普比我们多知道很多事情。”靠近他的伙伴也许会听见这句话。
无论如何，居民们的希望总算大部分得到满足了。一方面是由于机会，另一方面也由于他们领袖的惊人智慧，使他们得到很多的好处。他们现在已经占有了一个巨大的石洞，虽然火把的光线太暗，还没法准确估计石洞到底有多大，然而肯定是可以用砖头把它隔成许多房间的，即使不能把它当作一幢住宅，至少也可以作为一间宽大的公寓。湖水改道以后，再也不会回来了。这个地方可以随便利用。
目前还有两个困难：首先，怎样能使这个岩石中间的洞窟得到阳光；其次，必须想法子使进出方便一些，头顶上的花岗石很厚，要想从上面取得光源是不可能的，因此只有把临向大海的岩壁凿穿。赛勒斯·史密斯在走下来的时候，大致估计了一下甬道的坡度和长度，他认为外壁不可能太厚。如果能让光线从这里进来，那么也一定能够打开一扇门，因为门和窗凿起来都一样，只是需要在外面安装一个梯子，这也不是难事。
史密斯把他的想法告诉了大家。
“那么，史密斯先生，我们就开始干吧！”潘克洛夫说。“我这儿有鹤嘴锄，很快就可以把墙壁凿透。你告诉我在哪儿动手啊？”
“这儿，”工程师说，他把强壮的水手带到一个地方，这里的石壁凹进去相当深，岩石的厚度比别处要薄得多。
潘克洛夫在火把的照耀下向花岗石进攻了。碎石迸得到处都是。凿了半个钟头，纳布上去替换他，然后吉丁·史佩莱又替换了纳布。
他们继续干了两个钟头，开始怀疑了，觉得这里大概不是鹤嘴锄能凿通的。正在这时候，吉丁·史佩莱最后一锄竟凿穿了岩石，工具脱手掉到外边去了。
“哈哈！”潘克洛夫喊了起来。
这里的石壁只有三英尺厚。
史密斯把眼睛凑在壁孔上，这里离地面有八十英尺。前面伸展着海岸和小岛，远处是辽阔无边的海洋。
阳光透过缺口，照亮了这个壮丽宏伟的石洞。石洞左边的高度和宽度都至多不过三十英尺，右边却非常宽敞，圆形的顶壁高达八十英尺以上。
洞里的穹窿就好象教堂中央的圆顶，由许多不规则的花岗石柱支持着。这些石柱有的象侧面的扶壁，有的象椭圆形的拱门，上面点缀着许多刻划鲜明的花纹。在阴暗的角落里，还隐藏着许多突出的图案，象挂着的装饰品似的。通过这些石柱所形成的奇形怪状的拱门，隐隐约约透过一些光线来。这个山洞象是人类所有的拜占庭、罗马和哥特式建筑艺术的综合体。然而这却是大自然创造出来的。大自然在花岗石中一手造成了这亚亨伯拉式的洞天福地。
居民们不住赞赏这个地方。他们原先以为这里只有一个狭小的石洞，结果却发现了一座神奇的官殿，纳布象进了大庙似的，把帽子也摘下来了！
人人都大声地赞不绝口。欢笑声充满了石洞，回音反复传播，最后才消失在黑暗的中堂里。
“喂，朋友们！”赛勒斯·史密斯大声说，“等我们在这里开了窗户以后，我们就把左边当作房间和仓库，这一边壮丽的石洞要留作书房和我们的博物馆！”
“我们给它起一个什么名字呢？”赫伯特问道。
“‘花岗石宫’。”史密斯说。他的伙伴们听了以后，又欢呼起来，表示赞同。
火把已经快烧完了，他们不得不再从甬道回到高地上去。大家决定把整理新住宅的必要工作放到第二天再做。
临走以前，赛勒斯·史密斯又趴在黑黝黝的井口上探望了一下井底的海面，并且仔细听了一会凡。井底丝毫没有响动，连深处常有的汹涌波涛声也没有。他又往下扔了一根燃烧的树枝。一刹那间，照亮了井的周围，然而还是和第一次一样，没有看见任何可疑的东西。
即使有什么水怪由于潮水突然不流一时找不到新的出口而大吃一惊，现在一定也已经从这条地下通道回到大海里去了。
工程师呆呆地站在那里，注视着深渊，一句话也不说。
水手走到他的身边，碰了一下他的胳膊，喊道：“史密斯先生！”
“什么事，朋友？”工程师好象刚从梦中醒来，开口反问。
“火把就要灭了。”
“走吧！”赛勒斯·史密斯说。
小队离开了石洞，开始往漆黑的甬道上爬去。托普跟在最后，还不时低低咆哮。往上走是相当困难的。居民们在上面的石洞里休息了几分钟。在这漫长的花岗石梯阶上，这里好象是一个中途的休息站。接着他们又继续往上爬去。
不久就呼吸到比较新鲜的空气了。石壁上晶莹的水滴已经蒸发掉了。光亮的火把开始黯淡下来，纳布手里的一支已经熄灭了。如果不想在黑暗中瞎摸，就必须加速前进。
他们加快了步伐，将近四点钟的时候，赛勒斯·史密斯和他的伙伴们走出了甬道；这时候，水手的火把也灭了。