The next day, the 30th of October, all was ready for the proposed exploring expedition, which recent events had rendered so necessary. In fact, things had so come about that the settlers in Lincoln Island no longer needed help for themselves, but were even able to carry it to others.
It was therefore agreed that they should ascend1 the Mercy as far as the river was navigable. A great part of the distance would thus be traversed without fatigue2, and the explorers could transport their provisions and arms to an advanced point in the west of the island.
It was necessary to think not only of the things which they should take with them, but also of those which they might have by chance to bring back to Granite3 House. If there had been a wreck4 on the coast, as was supposed, there would be many things cast up, which would be lawfully5 their prizes. In the event of this, the cart would have been of more use than the light canoe, but it was heavy and clumsy to drag, and therefore more difficult to use; this led Pencroft to express his regret that the chest had not contained, besides "his halfpound of tobacco," a pair of strong New Jersey6 horses, which would have been very useful to the colony!
The provisions, which Neb had already packed up, consisted of a store of meat and of several gallons of beer, that is to say enough to sustain them for three days, the time which Harding assigned for the expedition. They hoped besides to supply themselves on the road, and Neb took care not to forget the portable stove.
The only tools the settlers took were the two woodmen's axes, which they could use to cut a path through the thick forests, as also the instruments, the telescope and pocket-compass.
For weapons they selected the two flint-lock guns, which were likely to be more useful to them than the percussion8 fowling-pieces, the first only requiring flints which could be easily replaced, and the latter needing fulminating caps, a frequent use of which would soon exhaust their limited stock. However, they took also one of the carbines and some cartridges9. As to the powder, of which there was about fifty pounds in the barrel, a small supply of it had to be taken, but the engineer hoped to manufacture an explosive substance which would allow them to husband it. To the firearms were added the five cutlasses well sheathed10 in leather, and, thus supplied, the settlers could venture into the vast forest with some chance of success.
It is useless to add that Pencroft, Herbert, and Neb, thus armed, were at the summit of their happiness, although Cyrus Harding made them promise not to fire a shot unless it was necessary.
At six in the morning the canoe put off from the shore; all had embarked11, including Top, and they proceeded to the mouth of the Mercy.
The tide had begun to come up half an hour before. For several hours, therefore, there would be a current, which it was well to profit by, for later the ebb12 would make it difficult to ascend the river. The tide was already strong, for in three days the moon would be full, and it was enough to keep the boat in the center of the current, where it floated swiftly along between the high banks without its being necessary to increase its speed by the aid of the oars13. In a few minutes the explorers arrived at the angle formed by the Mercy and exactly at the place where, seven months before, Pencroft had made his first raft of wood.
After this sudden angle the river widened and flowed under the shade of great evergreen14 firs.
The aspect of the banks was magnificent. Cyrus Harding and his companions could not but admire the lovely effects so easily produced by nature with water and trees. As they advanced the forest element diminished. On the right bank of the river grew magnificent specimens15 of the ulmaceae tribe, the precious elm, so valuable to builders, and which withstands well the action of water. Then there were numerous groups belonging to the same family, among others one in particular, the fruit of which produces a very useful oil. Further on, Herbert remarked the lardizabala, a twining shrub16 which, when bruised17 in water, furnishes excellent cordage; and two or three ebony trees of a beautiful black, crossed with capricious veins18.
From time to time, in certain places where the landing was easy, the canoe was stopped, when Gideon Spilett, Herbert, and Pencroft, their guns in their hands, and preceded by Top, jumped on shore. Without expecting game, some useful plant might be met with, and the young naturalist19 was delighted with discovering a sort of wild spinach20, belonging to the order of chenopodiaceae, and numerous specimens of cruciferae, belonging to the cabbage tribe, which it would certainly be possible to cultivate by transplanting. There were cresses, horseradish, turnips21, and lastly, little branching hairy stalks, scarcely more than three feet high, which produced brownish grains.
Do you know what this plant is?" asked Herbert of the sailor.
"Tobacco!" cried Pencroft, who evidently had never seen his favorite plant except in the bowl of his pipe.
"No, Pencroft," replied Herbert; "this is not tobacco, it is mustard."
"Mustard be hanged!" returned the sailor; "but if by chance you happen to come across a tobacco-plant, my boy, pray don't scorn that!"
"We shall find it some day!" said Gideon Spilett.
"Well!" exclaimed Pencroft, "when that day comes, I do not know what more will be wanting in our island!"
These different plants, which had been carefully rooted up, were carried to the canoe, where Cyrus Harding had remained buried in thought.
The reporter, Herbert, and Pencroft in this manner frequently disembarked, sometimes on the right bank, sometimes on the left bank of the Mercy.
The latter was less abrupt22, but the former more wooded. The engineer ascertained23 by consulting his pocket-compass that the direction of the river from the first turn was obviously southwest and northeast, and nearly straight for a length of about three miles. But it was to be supposed that this direction changed beyond that point, and that the Mercy continued to the north-west, towards the spurs of Mount Franklin, among which the river rose.
During one of these excursions, Gideon Spilett managed to get hold of two couples of living gallinaceae. They were birds with long, thin beaks24, lengthened25 necks, short wings, and without any appearance of a tail. Herbert rightly gave them the name of tinamous, and it was resolved that they should be the first tenants26 of their future poultry-yard.
But till then the guns had not spoken, and the first report which awoke the echoes of the forest of the Far West was provoked by the appearance of a beautiful bird, resembling the kingfisher.
"I recognize him!" cried Pencroft, and it seemed as if his gun went off by itself.
"What do you recognize?" asked the reporter.
"The bird which escaped us on our first excursion, and from which we gave the name to that part of the forest."
"A jacamar!" cried Herbert.
It was indeed a jacamar, of which the plumage shines with a metallic27 luster28. A shot brought it to the ground, and Top carried it to the canoe. At the same time half a dozen lories were brought down. The lory is of the size of a pigeon, the plumage dashed with green, part of the wings crimson29, and its crest30 bordered with white. To the young boy belonged the honor of this shot, and he was proud enough of it. Lories are better food than the jacamar, the flesh of which is rather tough, but it was difficult to persuade Pencroft that he had not killed the king of eatable birds. It was ten o'clock in the morning when the canoe reached a second angle of the Mercy, nearly five miles from its mouth. Here a halt was made for breakfast under the shade of some splendid trees. The river still measured from sixty to seventy feet in breadth, and its bed from five to six feet in depth. The engineer had observed that it was increased by numerous affluents31, but they were unnavigable, being simply little streams. As to the forest, including Jacamar Wood, as well as the forests of the Far West, it extended as far as the eye could reach. In no place, either in the depths of the forests or under the trees on the banks of the Mercy, was the presence of man revealed. The explorers could not discover one suspicious trace. It was evident that the woodman's axe7 had never touched these trees, that the pioneer's knife had never severed32 the creepers hanging from one trunk to another in the midst of tangled33 brushwood and long grass. If castaways had landed on the island, they could not have yet quitted the shore, and it was not in the woods that the survivors34 of the supposed shipwreck35 should be sought.
The engineer therefore manifested some impatience36 to reach the western coast of Lincoln Island, which was at least five miles distant according to his estimation.
The voyage was continued, and as the Mercy appeared to flow not towards the shore, but rather towards Mount Franklin, it was decided37 that they should use the boat as long as there was enough water under its keel to float it. It was both fatigue spared and time gained, for they would have been obliged to cut a path through the thick wood with their axes. But soon the flow completely failed them, either the tide was going down, and it was about the hour, or it could no longer be felt at this distance from the mouth of the Mercy. They had therefore to make use of the oars. Herbert and Neb each took one, and Pencroft took the scull. The forest soon became less dense38, the trees grew further apart and often quite isolated39. But the further they were from each other the more magnificent they appeared, profiting, as they did, by the free, pure air which circulated around them.
What splendid specimens of the flora40 of this latitude41! Certainly their presence would have been enough for a botanist42 to name without hesitation43 the parallel which traversed Lincoln Island.
They were, in fact, those splendid trees, the giants of the extratropical zone, the congeners of the Australian and New Zealand eucalyptus45, both situated46 under the same latitude as Lincoln Island. Some rose to a height of two hundred feet. Their trunks at the base measured twenty feet in circumference47, and their bark was covered by a network of farrows containing a red, sweet-smelling gum. Nothing is more wonderful or more singular than those enormous specimens of the order of the myrtaceae, with their leaves placed vertically48 and not horizontally, so that an edge and not a surface looks upwards49, the effect being that the sun's rays penetrate50 more freely among the trees.
The ground at the foot of the eucalypti was carpeted with grass, and from the bushes escaped flights of little birds, which glittered in the sunlight like winged rubies51.
"These are something like trees!" cried Neb; "but are they good for anything?"
"Pooh!" replied Pencroft. "Of course there are vegetable giants as well as human giants, and they are no good, except to show themselves at fairs!"
"I think that you are mistaken, Pencroft," replied Gideon Spilett, "and that the wood of the eucalyptus has begun to be very advantageously employed in cabinet-making."
"And I may add," said Herbert, "that the eucalyptus belongs to a family which comprises many useful members; the guava-tree, from whose fruit guava jelly is made; the clove-tree, which produces the spice; the pomegranate- tree, which bears pomegranates; the Eugeacia Cauliflora, the fruit of which is used in making a tolerable wine; the Ugui myrtle, which contains an excellent alcoholic52 liquor; the Caryophyllus myrtle, of which the bark forms an esteemed53 cinnamon; the Eugenia Pimenta, from whence comes Jamaica pepper; the common myrtle, from whose buds and berries spice is sometimes made; the Eucalyptus manifera, which yields a sweet sort of manna; the Guinea Eucalyptus, the sap of which is transformed into beer by fermentation; in short, all those trees known under the name of gum-trees or iron-bark trees in Australia, belong to this family of the myrtaceae, which contains forty-six genera and thirteen hundred species!"
The lad was allowed to run on, and he delivered his little botanical lecture with great animation54. Cyrus Harding listened smiling, and Pencroft with an indescribable feeling of pride.
"Very good, Herbert," replied Pencroft, "but I could swear that all those useful specimens you have just told us about are none of them giants like these!"
"That is true, Pencroft."
"That supports what I said," returned the sailor, "namely, that these giants are good for nothing!"
"There you are wrong, Pencroft," said the engineer; "these gigantic eucalypti, which shelter us, are good for something."
"And what is that?"
"To render the countries which they inhabit healthy. Do you know what they are called in Australia and New Zealand?"
"No, captain."
"They are called 'fever trees.'"
"Because they give fevers?"
"No, because they prevent them!"
"Good. I must note that," said the reporter.
"Note it then, my dear Spilett; for it appears proved that the presence of the eucalyptus is enough to neutralize55 miasmas56. This natural antidote57 has been tried in certain countries in the middle of Europe and the north of Africa where the soil was absolutely unhealthy, and the sanitary58 condition of the inhabitants has been gradually ameliorated. No more intermittent59 fevers prevail in the regions now covered with forests of the myrtaceae. This fact is now beyond doubt, and it is a happy circumstance for us settlers in Lincoln Island."
"Ah! what an island! What a blessed island!" cried Pencroft. "I tell you, it wants nothing--unless it is--"
"That will come, Pencroft, that will be found," replied the engineer; "but now we must continue our voyage and push on as far as the river will carry our boat!"
The exploration was therefore continued for another two miles in the midst of country covered with eucalypti, which predominated in the woods of this portion of the island. The space which they occupied extended as far as the eye could reach on each side of the Mercy, which wound along between high green banks. The bed was often obstructed60 by long weeds, and even by pointed61 rocks, which rendered the navigation very difficult. The action of the oars was prevented, and Pencroft was obliged to push with a pole. They found also that the water was becoming shallower and shallower, and that the canoe must soon stop. The sun was already sinking towards the horizon, and the trees threw long shadows on the ground. Cyrus Harding, seeing that he could not hope to reach the western coast of the island in one journey, resolved to camp at the place where any further navigation was prevented by want of water. He calculated that they were still five or six miles from the coast, and this distance was too great for them to attempt during the night in the midst of unknown woods.
The boat was pushed on through the forest, which gradually became thicker again, and appeared also to have more inhabitants; for if the eyes of the sailor did not deceive him, he thought he saw bands of monkeys springing among the trees. Sometimes even two or three of these animals stopped at a little distance from the canoe and gazed at the settlers without manifesting any terror, as if, seeing men for the first time, they had not yet learned to fear them. It would have been easy to bring down one of these quadramani with a gunshot, and Pencroft was greatly tempted62 to fire, but Harding opposed so useless a massacre63. This was prudent64, for the monkeys, or apes rather, appearing to be very powerful and extremely active, it was useless to provoke an unnecessary aggression65, and the creatures might, ignorant of the power of the explorers' firearms, have attacked them. It is true that the sailor considered the monkeys from a purely66 alimentary67 point of view, for those animals which are herbivorous make very excellent game; but since they had an abundant supply of provisions, it was a pity to waste their ammunition68.
Towards four o'clock, the navigation of the Mercy became exceedingly difficult, for its course was obstructed by aquatic69 plants and rocks. The banks rose higher and higher, and already they were approaching the spurs of Mount Franklin. The source could not be far off, since it was fed by the water from the southern slopes of the mountain.
"In a quarter of an hour," said the sailor, "we shall be obliged to stop, captain."
"Very well, we will stop, Pencroft, and we will make our encampment for the night."
"At what distance are we from Granite House?" asked Herbert.
"About seven miles," replied the engineer, "taking into calculation, however, the detours70 of the river, which has carried us to the northwest."
"Shall we go on?" asked the reporter.
"Yes, as long as we can," replied Cyrus Harding. "To-morrow, at break of day, we will leave the canoe, and in two hours I hope we shall cross the distance which separates us from the coast, and then we shall have the whole day in which to explore the shore."
"Go ahead!" replied Pencroft.
But soon the boat grated on the stony71 bottom of the river, which was now not more than twenty feet in breadth. The trees met like a bower72 overhead, and caused a half-darkness. They also heard the noise of a waterfall, which showed that a few hundred feet up the river there was a natural barrier.
Presently, after a sudden turn of the river, a cascade73 appeared through the trees. The canoe again touched the bottom, and in a few minutes it was moored74 to a trunk near the right bank.
It was nearly five o'clock. The last rays of the sun gleamed through the thick foliage75 and glanced on the little waterfall, making the spray sparkle with all the colors of the rainbow. Beyond that, the Mercy was lost in the bushwood, where it was fed from some hidden source. The different streams which flowed into it increased it to a regular river further down, but here it was simply a shallow, limpid76 brook77.
It was agreed to camp here, as the place was charming. The colonists78 disembarked, and a fire was soon lighted under a clump79 of trees, among the branches of which Cyrus Harding and his companions could, if it was necessary, take refuge for the night.
Supper was quickly devoured80, for they were very hungry, and then there was only sleeping to think of. But, as roarings of rather a suspicious nature had been heard during the evening, a good fire was made up for the night, so as to protect the sleepers81 with its crackling flames. Neb and Pencroft also watched by turns, and did not spare fuel. They thought they saw the dark forms of some wild animals prowling round the camp among the bushes, but the night passed without incident, and the next day, the 31st of October, at five o'clock in the morning, all were on foot, ready for a start.
第二天，10月30日，大家都为参加预定的探险作好了准备。最近的许多事情使这次探险变得非常必要。的确，现在情况不同了，林肯岛上的居民不但可以不需要别人帮助，而且能够帮助别人了。
因此大家一致的意见是：只要能够走得通，就尽可能地往慈悲河上游驶去。这样探险队就可以毫不费力地走完相当长的一段距离，同时还可以把他们的粮食和武器运到荒岛的西面去。
现在除了要考虑带去的东西以外，还必须考虑到他们可能带一批东西回来。假如真和想象中的一样，海滩上曾经有船遇险的话，那么就会有很多被遗留下来的东西，这些东西，他们是可以合法占有的。在这种情况下，大车就要比轻便的平底船有用得多了。可是大车过于笨重，拉起来很不方便，于是潘克洛夫又感到遗憾了，以前是认为箱子里没给他预备“半斤烟草”，现在则认为箱子里缺少两匹新泽西的壮马，因为这对探险队说来，是非常有用的：
纳布已经把粮食包装起来了，其中包括大量肉类和好几加仑的啤酒，这些东西足够他们吃三天——也就是史密斯所规定的探险期限。此外，他们还打算一路上补充，纳布没有忘记携带轻便火炉。
他们所带的工具只有两把砍柴斧，在路过密林的时候，可以用来开路；仪器方面，带了一副望远镜和一个袖珍指南针。
至于武器，他们选择了两支燧发枪，因为他们认为带燧发枪比撞针枪更合适些。燧发枪需要的火石很容易补充，而撞针枪却必须用雷管，如果经常使用，他们有限的贮存就要用完了。可是他们也带了一支马枪和一些弹药。至于火药，桶里大约共有五十斤，他们必须稍微带一些，但是工程师打算自己制造一种炸药，这样他们就可以把火药节省下来。除了火器之外，他们又带了五把妥藏在皮鞘里的尖刀。有了这样的装备，难怪居民们可以怀着成功的希望，到大森林里去冒险了。
不用说，潘克洛夫、赫伯特和纳布有了这样的装备，自然是十分满意；当然，赛勒斯.史密斯叫他们提出保证，非不得已不随意乱放一枪。
早上六点钟，平底船离岸了；包括托普在内，全体都上了船，他们开始向慈悲河口驶去。
半个钟头以前就涨潮了。潮水将要往里流几小时，这对航行是有利的，等到退潮的时候，逆流而上，就会增加一些困难。三天之内月亮就要圆了，潮势已经很猛，足够把船身保持在潮流的中心，使它漂浮着在高耸的两岸之间迅速前进，而不需要用双桨来增加它的速度。几分钟以后，探险家们就来到慈悲河的一个拐角处。七个月以前，潘克洛夫就是在这儿制造第一只木筏的。
过了这个突出的拐角以后，河面开阔多了，船从高大的常绿枞树浓荫下驶过。
慈悲河两岸的景色非常秀丽。大自然用河水和树木随意安排的美景，使赛勒斯.史密斯和他的伙伴情不自禁地赞叹起来。他们愈往前走，树木的种类就愈多。河右岸生长着美丽的榆树科植物，这种为建筑师珍视的榆树，即使长期浸在水里，也不致腐烂。此外还有同科的其他许多类树木，其中有一种较为特殊，它的果仁含有一种非常有用的油。再往前去，赫伯特又发现了木通科植物，这是一种盘藤灌木，它的枝条在水里浸过以后，可以做成极好的索具，他还看见两三棵黑檀，带有美丽的黑色奇异花纹。
平底船一到好靠岸的地方总要停下来，吉丁.史佩莱、赫伯特和潘克洛夫就拿着枪，随着托普跳上去。除了猎得一些野味外，还可以碰到一些有用的植物；少年自然学家发现了一种藜科的野生菠菜和白菜类的许多十字花科蔬菜——这种蔬菜是一定可以移植的——感到非常高兴，这里还有水芹、萝卜、芜菁，最后还有一些一米高的多毛多枝丫的草茎植物，结着褐色的种籽。
“你知道这是什么植物吗？”赫伯特向水手问道。
“烟草！”潘克洛夫大声说，显然，除了在他的烟斗里以外，他从来也没有见过这种他所心爱的植物。
“不是！潘克洛夫，”赫伯特说，“这不是烟草，是芥菜。”
“管它什么芥菜！”水手说；“可是孩子，假如你碰到烟草，可千万别放过它！”
“总有一天我们会找到的！”吉丁.史佩莱说。
“好吧！”潘克洛夫大声说，“等到那时候，我就想不出我们的岛上还缺些什么了！”
他们把各种各样的植物小心翼翼地连根挖起来，带回了平底船，这时，赛勒斯.史密斯还在那里想心事。
通讯记者、赫伯特和潘克洛夫就这样不断地上岸，有时上慈悲河的右岸，有时上左岸。
慈悲河的左岸比较平坦，可是右岸的树木却更茂密。工程师看了一下他的袖珍指南针，河的方向从第一个拐弯起，显然是从西南到东北，大约三英里之内几乎是笔直的。然而在第一个拐弯以后，方向就可能改变了，慈悲河上游可能朝西北伸去，直到河流的发源地，富兰克林山的支脉。
途中有一次登岸，吉丁.史佩莱竟捉住了四只鹑鸡。这种鸟的嘴又薄又长，头颈细长，翅膀短小，尾巴几乎没有。赫伯特恰如其分地把它们叫做鹌鹑，他们决定饲养这些鹑鸡，作为他们未来家禽场上的第一批住客。
直到这时候，他们还没有开过枪，第一声枪响是在远西森林中发出的，他们发现了一只类似鱼狗的美丽飞鸟。
“我认识它！”潘克洛夫喊道，他的枪不由自主地从肩膀上滑了下来。
“你认识什么？”通讯记者问道。
“我们第一次打猎的时候逃走的那只飞鸟，我们曾用它来给那一带的森林命名。”
“啄木鸟！”赫伯特喊道。
不错，这是一只啄木鸟，它的羽毛发着金属的光泽。一颗子弹把它打下来，托普把它衔到平底船去了，同时又打下了半打猩猩鹦鹉。它们的大小和鸽子差不多，羽毛掺杂着绿色，翅膀部分是深红的，冠毛镶着一道白边。这些鹦鹉是少年打下来的，他感到非常得意。猩猩鹦鹉比啄木鸟要好吃得多，因为啄木鸟的肉太粗了。可是要让潘克洛夫承认他所打到的不是最好吃的飞禽，却不是一件容易的事。早上十点钟，平底船来到了离慈悲河口将近五英里的第二个拐角。他们就在这里停下来，在美丽的树荫下吃早饭。这里河流的宽度还有六十到七十英尺，河床的深度则在五六英尺左右。工程师发现支流愈来愈多了，可是这些支流不能通航，因为它们不过是一些小溪。周围的森林（包括啄木鸟林和远西森林在内）一眼望不到边。无论是在森林的深处，还是在慈悲河岸的大树底下，都没有人迹。探险的人们找不到丝毫可疑的迹象。看得出来，这些树木根本没有被砍柴斧碰过。丫杈横生的灌木和深草丛中大树间的爬藤也不曾被开路的人用刀砍过。假如遇难的人确是上过荒岛的话，他们决不会已经离岸了，然而丛林里却没法找到这些在假定的遇难中脱险的人。
因此工程师急于要到林肯岛的西海岸去，据他估计，这段距离至少还有五英里。
他们继续航行，慈悲河现在好象不是朝着海岸流，而是往富兰克林山流去。他们决定只要河水还能叫船浮得起来，就照常用平底船向前进。这样既省力，又不浪费时间，要不然，他们就必须用斧头在密林中开路。可是潮水不久就失去了作用，不知是因为退潮（现在已经到退潮的时候了），还是离开慈悲河口太远，总之，觉察不到海潮是在往前流动了，于是他们只好利用双桨，赫伯特和纳布每人拿了一支，潘克洛夫摇起橹来继续逆流前进。树木愈来愈稀疏，树木之间的距离隔得很远，经常有些大树孤零零地耸立着。可是它们彼此距离愈远，长得也就愈加美丽，这是因为树木之间空气流通的缘故。
这一带的植物是多么茂盛美丽啊！植物学家看了这些花草树木，一定可以毫不犹豫地说出林肯岛的纬度来的。
“有加利树！”赫伯特喊道。
不错，正是这种美丽的树木，这是一种亚热带的大树，和澳大利亚、新西兰（这两处都和林肯岛在同一纬度）的有加利树属于一类，这些树木有的高达二百英尺，树干下部周围有二十英尺，凹凸不平的树皮有五英寸厚，里面含有芳香的红色树脂。这种高大的桃金娘科树木真是新奇少有，它们的叶子是垂直的而不是水平的，也就是说，向上长着的是叶边，而不是叶面，因此，阳光很容易透过树木射下来。
有加利树底下是一片绿茵，一群小鸟从灌木丛中逃出来，它们在阳光里振翼飞翔，象长了翅膀的红宝石。
“好象是一种乔木！”纳布喊道；“可是它有用吗？”
“嘿！”潘克洛夫答道。“这些大树就好象大胖子似的，中看不中用。”
“我认为你错了，潘克洛夫，”吉丁.史佩莱说，“有加利树是制造家具的上等木料。”
“我还要补充一句，”赫伯特说，“有加利树的这一科包括很多有用的种类，其中番石榴的果实可以制造果子酱；丁香树出产香料；安石榴树结安石榴；桃金娘丁香树的果实可以酿造美酒；乌葛杨梅树含有很浓的酒精成分；石竹科的杨梅树皮可以制成珍贵的肉桂；尤琴椒树可以制造牙买加辣椒；普通杨梅的嫩芽和果子里有时可以提取胡椒。有加利树可以提供一种香料，几内亚有加利树的树液经过发酵可以制成啤酒。一句话，澳大利亚所有的橡皮树和铁皮树都属于这种桃金娘科，它包括四十六属和一千三百种。”
少年滔滔不绝地往下说，他兴致勃勃地把他在植物学上的一点常识全谈了出来。赛勒斯.史密斯一面听，一面微笑着，而潘克洛夫别有一种骄傲的心情。
“很好！赫伯特，”潘克洛夫说，“可是我敢打赌，这些大树决不是你刚才提到的那些有用的品种！”
“不错，潘克洛夫。”
“这就证实我刚才的话不错了，”水手接着说，“这些大树皮有什么用处！”
“那你就错了，潘克洛夫，”工程师说，“我们头上这些高大的有加利树是有些用处的。”
“有什么用处？”
“保持当地的环境卫生。你知道澳洲和新西兰的居民把它们叫做什么吗？”
“不知道，史密斯先生。”
“把它们叫做‘寒热病树’。”
“是因为它们散布寒热病吗，”
“不，因为它们防止寒热病！”
“好，我要记下来。”通讯记者说。
“记下来吧！亲爱的史佩莱。有加利树可以驱除瘴气已经得到证实了。在中欧和北非，有许多国家的土壤对健康是非常有害的，这种自然的解毒药已经在那里试验过了，当地居民的卫生条件逐渐得到了改善。现在凡是有桃金娘科森林的地区，都没有疟疾了。这是已经得到证明的事实，因此这样的环境对我们这伙林肯岛上的居民是非常有利的。”
“啊！这个岛真不错！这个岛真太好了！”潘克洛夫喊道。“我说，这儿什么都有，只差……”
“会有的，潘克洛夫，会找到的，”工程师回答说；“可是现在我们要继续航行，河流允许我们航到哪里，我们就航到哪里！”
他们又继续前进了两个钟头，这一带长满了有加利树，荒岛的这部分森林里，主要是这种树。慈悲河弯弯曲曲地向前伸去，夹岸是高耸的绿色陡坡，河岸两边，都是望不到边的有加利树。河床里不时发现很长的水草，甚至还有一些突出的岩石，给航行增加很大的困难。划桨受到了阻碍，于是潘克洛夫只好用一支长竿来撑船。他们发觉河水愈来愈浅，平底船很快就要不好走了。太阳已经向水平线沉下去，满地都是长长的树影。赛勒斯.史密斯知道要想一下子就到达荒岛的西岸是不可能的了，即使要继续航行，河水又太浅，于是决定就地宿营。他估计他们离海滨还有五六英里，要在黑夜穿过陌生的丛林走完这一段距离，显然是太远了。
平底船穿过森林向前行驶，现在森林又渐渐地密起来，而且看来这里“人烟”似乎比较稠密，假如水手没有看错的话，他好象看见树上有许多猴子在跳跃。有两三只猴子甚至来到平底船的近旁，瞪着眼瞧他们，一点也不害怕，仿佛是初次看到人类，还不懂得害怕似的。要想一枪打中一只这样的猴子是非常容易的。潘克洛夫很想试一试，可是史密斯却不赞成这种毫无意义的屠杀。这样做比较谨慎，因为这种猴子（其实是人猿）看起来非常灵活有力，无缘无故地侵犯它们大可不必，况且它们很可能会不顾火器的威力，向探险家进攻。不错，水手是纯粹从食物观点来看这群猴子的，他知道这种草食动物是极佳的野味，可是既然他们的口粮还很充裕，那么浪费火药就未免有些可惜了。
到四点钟的时候，由于水生植物和岩石阻塞了河道，在慈悲河上航行更加困难了。两岸愈来愈高，他们已经接近富兰克林山的支脉，离慈悲河的源头不会太远了，因为它就是由南面山坡的涧水汇合而成的。
“一刻钟以内，”水手说，“我们就非停船不可了，史密斯先生。”
“很好，就停吧，潘克洛夫，我们要扎一个野营。”
“我们离‘花岗石宫’有多远了？”赫伯特问道。
“把河道的弯曲也计算在内的话，”工程师说，“我们来到了西北方七英里左右的地方。”
“我们还要继续往前走吗？”通讯记者问道。
“是的，只要能往前走，我们还要往前走，”赛勒斯.史密斯回答。“明儿天一亮就离开平底船，我希望在两个钟头之内能够到达海滨，那样我们就可以有一整天的工夫巡视海岸了。”
“那么就往前走！”潘克洛夫道。
可是平底船马上触到了石头的河底，现在河宽至多不过二十英尺。两岸的树木在河上搭成一个凉棚，使周围的环境半明半暗。他们还听见奔腾澎湃的瀑布声，几百英尺的上游显然有一道天然的障碍。
河身突然拐了一个弯以后，他们透过树木的间隙看见一个瀑布。平底船又碰到河底了，几分钟以后，它在右侧的一棵大树下靠了岸。
快五点钟了。浓密的枝叶间闪耀着落日的余辉，它照在这个小小的瀑布上，使溅起的水珠形成了一道七彩长虹。再往前，慈悲河就在远处的灌木丛中消失了，那里隐蔽着它的源泉。在这以下有无数支流向它汇合拢来，使它成为一条正规的河流，可是在这儿它只是一脉清澈的浅溪。
周围景色优美，大家都同意在这里露宿。他们跳下船来，立刻在一丛小树下升起一堆篝火，假如必要的话，赛勒斯.史密斯和他的伙伴们还可以在附近的大树杈枝上过夜。
大家都饿了，他们风卷残云般地吃完了晚饭，然后只等睡觉。可是，在入夜的时候，他们听到一种可疑的咆哮声。为了保障这群人平安地睡觉，他们燃起了一堆旺盛的烈火，火堆僻僻啪啪地响着。纳布和潘克洛夫轮流守夜，不断地大量加添燃料。他们在黑暗中仿佛看见从灌木丛中出来一些野兽围绕着帐篷偷偷地走来走去。可是这一夜毕竟安然度过了。第二天，10月31日，他们早上五点钟就都起来了，准备重新上路。
