Île mystérieuse. English

Chapter 14

The next day, the 16th of April, and East­er Sun­day, the set­tlers is­sued from the Chim­neys at day­break, and pro­ceed­ed to wash their linen. The en­gi­neer in­tend­ed to man­ufac­ture soap as soon as he could pro­cure the nec­es­sary ma­te­ri­als–so­da or potash, fat or oil. The im­por­tant ques­tion of re­new­ing their wardrobe would be treat­ed of in the prop­er time and place. At any rate their clothes would last at least six months longer, for they were strong, and could re­sist the wear of man­ual la­bor. But all would de­pend on the sit­ua­tion of the is­land with re­gard to in­hab­it­ed land. This would be set­tled to-​day if the weath­er per­mit­ted.

The sun ris­ing above a clear hori­zon, an­nounced a mag­nif­icent day, one of those beau­ti­ful au­tumn days which are like the last farewells of the warm sea­son.

It was now nec­es­sary to com­plete the ob­ser­va­tions of the evening be­fore by mea­sur­ing the height of the cliff above the lev­el of the sea.

“Shall you not need an in­stru­ment sim­ilar to the one which you used yes­ter­day?” said Her­bert to the en­gi­neer.

“No, my boy,” replied the lat­ter, “we are go­ing to pro­ceed dif­fer­ent­ly, but in as pre­cise a way.”

Her­bert, wish­ing to learn ev­ery­thing he could, fol­lowed the en­gi­neer to the beach. Pen­croft, Neb, and the re­porter re­mained be­hind and oc­cu­pied them­selves in dif­fer­ent ways.

Cyrus Hard­ing had pro­vid­ed him­self with a straight stick, twelve feet long, which he had mea­sured as ex­act­ly as pos­si­ble by com­par­ing it with his own height, which he knew to a hair. Her­bert car­ried a plumb-​line which Hard­ing had giv­en him, that is to say, a sim­ple stone fas­tened to the end of a flex­ible fiber. Hav­ing reached a spot about twen­ty feet from the edge of the beach, and near­ly five hun­dred feet from the cliff, which rose per­pen­dic­ular­ly, Hard­ing thrust the pole two feet in­to the sand, and wedg­ing it up care­ful­ly, he man­aged, by means of the plumb-​line, to erect it per­pen­dic­ular­ly with the plane of the hori­zon.

That done, he re­tired the nec­es­sary dis­tance, when, ly­ing on the sand, his eye glanced at the same time at the top of the pole and the crest of the cliff. He care­ful­ly marked the place with a lit­tle stick.

Then ad­dress­ing Her­bert–“Do you know the first prin­ci­ples of ge­om­etry?” he asked.

“Slight­ly, cap­tain,” replied Her­bert, who did not wish to put him­self for­ward.

“You re­mem­ber what are the prop­er­ties of two sim­ilar tri­an­gles?”

“Yes,” replied Her­bert; “their ho­mol­ogous sides are pro­por­tion­al.”

“Well, my boy, I have just con­struct­ed two sim­ilar right-​an­gled tri­an­gles; the first, the small­est, has for its sides the per­pen­dic­ular pole, the dis­tance which sep­arates the lit­tle stick from the foot of the pole and my vi­su­al ray for hy­pothenuse; the sec­ond has for its sides the per­pen­dic­ular cliff, the height of which we wish to mea­sure, the dis­tance which sep­arates the lit­tle stick from the bot­tom of the cliff, and my vi­su­al ray al­so forms its hy­pothenuse, which proves to be pro­lon­ga­tion of that of the first tri­an­gle.”

“Ah, cap­tain, I un­der­stand!” cried Her­bert. “As the dis­tance from the stick to the pole is to the dis­tance from the stick to the base of the cliff, so is the height of the pole to the height of the cliff.”

“Just so, Her­bert,” replied the en­gi­neer; “and when we have mea­sured the two first dis­tances, know­ing the height of the pole, we shall on­ly have a sum in pro­por­tion to do, which will give us the height of the cliff, and will save us the trou­ble of mea­sur­ing it di­rect­ly.”

The two hor­izon­tal dis­tances were found out by means of the pole, whose length above the sand was ex­act­ly ten feet.

The first dis­tance was fif­teen feet be­tween the stick and the place where the pole was thrust in­to the sand.

The sec­ond dis­tance be­tween the stick and the bot­tom of the cliff was five hun­dred feet.

These mea­sure­ments fin­ished, Cyrus Hard­ing and the lad re­turned to the Chim­neys.

The en­gi­neer then took a flat stone which he had brought back from one of his pre­vi­ous ex­cur­sions, a sort of slate, on which it was easy to trace fig­ures with a sharp shell. He then proved the fol­low­ing pro­por­tions:–

15:500::10:x

500 x 10 = 5000

5000 / 15 = 333.3

From which it was proved that the gran­ite cliff mea­sured 333 feet in height.

Cyrus Hard­ing then took the in­stru­ment which he had made the evening be­fore, the space be­tween its two legs giv­ing the an­gu­lar dis­tance be­tween the star Al­pha and the hori­zon. He mea­sured, very ex­act­ly, the open­ing of this an­gle on a cir­cum­fer­ence which he di­vid­ed in­to 360 equal parts. Now, this an­gle by adding to it the twen­ty-​sev­en de­grees which sep­arat­ed Al­pha from the antarc­tic pole, and by re­duc­ing to the lev­el of the sea the height of the cliff on which the ob­ser­va­tion had been made, was found to be fifty- three de­grees. These fifty-​three de­grees be­ing sub­tract­ed from nine­ty de­grees–the dis­tance from the pole to the equa­tor–there re­mained thir­ty- sev­en de­grees. Cyrus Hard­ing con­clud­ed, there­fore, that Lin­coln Is­land was sit­uat­ed on the thir­ty-​sev­enth de­gree of the south­ern lat­itude, or tak­ing in­to con­sid­er­ation through the im­per­fec­tion of the per­for­mance, an er­ror of five de­grees, that it must be sit­uat­ed be­tween the thir­ty-​fifth and the for­ti­eth par­al­lel.

There was on­ly the lon­gi­tude to be ob­tained, and the po­si­tion of the is­land would be de­ter­mined, The en­gi­neer hoped to at­tempt this the same day, at twelve o’clock, at which mo­ment the sun would pass the merid­ian.

It was de­cid­ed that Sun­day should be spent in a walk, or rather an ex­plor­ing ex­pe­di­tion, to that side of the is­land be­tween the north of the lake and Shark Gulf, and if there was time they would push their dis­cov­er­ies to the north­ern side of Cape South Mandible. They would break­fast on the downs, and not re­turn till evening.

At half-​past eight the lit­tle band was fol­low­ing the edge of the chan­nel. On the oth­er side, on Safe­ty Islet, nu­mer­ous birds were grave­ly strut­ting. They were divers, eas­ily rec­og­nized by their cry, which much re­sem­bles the bray­ing of a don­key. Pen­croft on­ly con­sid­ered them in an eat­able point of view, and learnt with some sat­is­fac­tion that their flesh, though black­ish, is not bad food.

Great am­phibi­ous crea­tures could al­so be seen crawl­ing on the sand; seals, doubt­less, who ap­peared to have cho­sen the islet for a place of refuge. It was im­pos­si­ble to think of those an­imals in an al­imen­ta­ry point of view, for their oily flesh is de­testable; how­ev­er, Cyrus Hard­ing ob­served them at­ten­tive­ly, and with­out mak­ing known his idea, he an­nounced to his com­pan­ions that very soon they would pay a vis­it to the islet. The beach was strewn with in­nu­mer­able shells, some of which would have re­joiced the heart of a con­chol­ogist; there were, among oth­ers, the phasianel­la, the ter­ebrat­ual, etc. But what would be of more use, was the dis­cov­ery, by Neb, at low tide, of a large oys­terbed among the rocks, near­ly five miles from the Chim­neys.

“Neb will not have lost his day,” cried Pen­croft, look­ing at the spa­cious oys­ter-​bed.

“It is re­al­ly a for­tu­nate dis­cov­ery,” said the re­porter, “and as it is said that each oys­ter pro­duces year­ly from fifty to six­ty thou­sand eggs, we shall have an in­ex­haustible sup­ply there.”

“On­ly I be­lieve that the oys­ter is not very nour­ish­ing,” said Her­bert.

“No,” replied Hard­ing. “The oys­ter con­tains very lit­tle ni­tro­gen, and if a man lived ex­clu­sive­ly on them, he would have to eat not less than fif­teen to six­teen dozen a day.”

“Cap­ital!” replied Pen­croft. “We might swal­low dozens and dozens with­out ex­haust­ing the bed. Shall we take some for break­fast?”

And with­out wait­ing for a re­ply to this pro­pos­al, know­ing that it would be ap­proved of, the sailor and Neb de­tached a quan­ti­ty of the mol­luscs. They put them in a sort of net of hi­bis­cus fiber, which Neb had man­ufac­tured, and which al­ready con­tained food; they then con­tin­ued to climb the coast be­tween the downs and the sea.

From time to time Hard­ing con­sult­ed his watch, so as to be pre­pared in time for the so­lar ob­ser­va­tion, which had to be made ex­act­ly at mid­day.

All that part of the is­land was very bar­ren as far as the point which closed Union Bay, and which had re­ceived the name of Cape South Mandible. Noth­ing could be seen there but sand and shells, min­gled with de­bris of la­va. A few sea-​birds fre­quent­ed this des­olate coast, gulls, great al­ba­tross­es, as well as wild duck, for which Pen­croft had a great fan­cy. He tried to knock some over with an ar­row, but with­out re­sult, for they sel­dom perched, and he could not hit them on the wing.

This led the sailor to re­peat to the en­gi­neer,–

“You see, cap­tain, so long as we have not one or two fowl­ing-​pieces, we shall nev­er get any­thing!”

“Doubt­less, Pen­croft,” replied the re­porter, “but it de­pends on you. Pro­cure us some iron for the bar­rels, steel for the ham­mers, salt­peter. coal and sul­phur for pow­der, mer­cury and ni­tric acid for the ful­mi­nate, and lead for the shot, and the cap­tain will make us first-​rate guns.”

“Oh!” replied the en­gi­neer, “we might, no doubt, find all these sub­stances on the is­land, but a gun is a del­icate in­stru­ment, and needs very par­tic­ular tools. How­ev­er, we shall see lat­er!”

“Why,” cried Pen­croft, “were we obliged to throw over­board all the weapons we had with us in the car, all our im­ple­ments, even our pock­et- knives?”

“But if we had not thrown them away, Pen­croft, the bal­loon would have thrown us to the bot­tom of the sea!” said Her­bert.

“What you say is true, my boy,” replied the sailor.

Then pass­ing to an­oth­er idea,–“Think,” said he, “how as­tound­ed Jonathan Forster and his com­pan­ions must have been when, next morn­ing, they found the place emp­ty, and the ma­chine flown away!”

“I am ut­ter­ly in­dif­fer­ent about know­ing what they may have thought,” said the re­porter.

“It was all my idea, that!” said Pen­croft, with a sat­is­fied air.

“A splen­did idea, Pen­croft!” replied Gideon Spilett, laugh­ing, “and which has placed us where we are.”

“I would rather be here than in the hands of the South­ern­ers,” cried the sailor, “es­pe­cial­ly since the cap­tain has been kind enough to come and join us again.”

“So would I, tru­ly!” replied the re­porter. “Be­sides, what do we want? Noth­ing.”

“If that is not–ev­ery­thing!” replied Pen­croft, laugh­ing and shrug­ging his shoul­ders. “But, some day or oth­er, we shall find means of go­ing away!”

“Soon­er, per­haps, than you imag­ine, my friends,” re­marked the en­gi­neer, “if Lin­coln Is­land is but a medi­um dis­tance from an in­hab­it­ed is­land, or from a con­ti­nent. We shall know in an hour. I have not a map of the Pa­cif­ic, but my mem­ory has pre­served a very clear rec­ol­lec­tion of its south­ern part. The lat­itude which I ob­tained yes­ter­day placed New Zealand to the west of Lin­coln Is­land, and the coast of Chile to the east. But be­tween these two coun­tries, there is a dis­tance of at least six thou­sand miles. It has, there­fore, to be de­ter­mined what point in this great space the is­land oc­cu­pies, and this the lon­gi­tude will give us present­ly, with a suf­fi­cient ap­prox­ima­tion, I hope.”

“Is not the archipela­go of the Po­moutous the near­est point to us in lat­itude?” asked Her­bert.

“Yes,” replied the en­gi­neer, “but the dis­tance which sep­arates us from it is more than twelve hun­dred miles.”

“And that way?” asked Neb, who fol­lowed the con­ver­sa­tion with ex­treme in­ter­est, point­ing to the south.

“That way, noth­ing,” replied Pen­croft.

“Noth­ing, in­deed,” added the en­gi­neer.

“Well, Cyrus,” asked the re­porter, “if Lin­coln Is­land is not more than two or three thou­sand miles from New Zealand or Chile?”

“Well,” replied the en­gi­neer, “in­stead of build­ing a house we will build a boat, and Mas­ter Pen­croft shall be put in com­mand–“

“Well then,” cried the sailor, “I am quite ready to be cap­tain–as soon as you can make a craft that’s able to keep at sea!”

“We shall do it, if it is nec­es­sary,” replied Cyrus Hard­ing.

But while these men, who re­al­ly hes­itat­ed at noth­ing, were talk­ing, the hour ap­proached at which the ob­ser­va­tion was to be made. What Cyrus Hard­ing was to do to as­cer­tain the pas­sage of the sun at the merid­ian of the is­land, with­out an in­stru­ment of any sort, Her­bert could not guess.

The ob­servers were then about six miles from the Chim­neys, not far from that part of the downs in which the en­gi­neer had been found af­ter his enig­mat­ical preser­va­tion. They halt­ed at this place and pre­pared for break­fast, for it was half-​past eleven. Her­bert went for some fresh wa­ter from a stream which ran near, and brought it back in a jug, which Neb had pro­vid­ed.

Dur­ing these prepa­ra­tions Hard­ing ar­ranged ev­ery­thing for his as­tro­nom­ical ob­ser­va­tion. He chose a clear place on the shore, which the ebbing tide had left per­fect­ly lev­el. This bed of fine sand was as smooth as ice, not a grain out of place. It was of lit­tle im­por­tance whether it was hor­izon­tal or not, and it did not mat­ter much whether the stick six feet high, which was plant­ed there, rose per­pen­dic­ular­ly. On the con­trary, the en­gi­neer in­clined it to­wards the south, that is to say, in the di­rec­tion of the coast op­po­site to the sun, for it must not be for­got­ten that the set­tlers in Lin­coln Is­land, as the is­land was sit­uat­ed in the South­ern Hemi­sphere, saw the ra­di­ant plan­et de­scribe its di­ur­nal arc above the north­ern, and not above the south­ern hori­zon.

Her­bert now un­der­stood how the en­gi­neer was go­ing to pro­ceed to as­cer­tain the cul­mi­na­tion of the sun, that is to say its pass­ing the merid­ian of the is­land or, in oth­er words, de­ter­mine due south. It was by means of the shad­ow cast on the sand by the stick, a way which, for want of an in­stru­ment, would give him a suit­able ap­proach to the re­sult which he wished to ob­tain.

In fact, the mo­ment when this shad­ow would reach its min­imum of length would be ex­act­ly twelve o’clock, and it would be enough to watch the ex­trem­ity of the shad­ow, so as to as­cer­tain the in­stant when, al­ter hav­ing suc­ces­sive­ly di­min­ished, it be­gan to length­en. By in­clin­ing his stick to the side op­po­site to the sun, Cyrus Hard­ing made the shad­ow longer, and con­se­quent­ly its mod­ifi­ca­tions would be more eas­ily as­cer­tained. In fact, the longer the nee­dle of a di­al is, the more eas­ily can the move­ment of its point be fol­lowed. The shad­ow of the stick was noth­ing but the nee­dle of a di­al. The mo­ment had come, and Cyrus Hard­ing knelt on the sand, and with lit­tle wood­en pegs, which he stuck in­to the sand, he be­gan to mark the suc­ces­sive diminu­tions of the stick’s shad­ow. His com­pan­ions, bend­ing over him, watched the op­er­ation with ex­treme in­ter­est. The re­porter held his chronome­ter in his hand, ready to tell the hour which it marked when the shad­ow would be at its short­est. More­over, as Cyrus Hard­ing was work­ing on the 16th of April, the day on which the true and the av­er­age time are iden­ti­cal, the hour giv­en by Gideon Spilett would be the true hour then at Wash­ing­ton, which would sim­pli­fy the cal­cu­la­tion. Mean­while as the sun slow­ly ad­vanced, the shad­ow slow­ly di­min­ished, and when it ap­peared to Cyrus Hard­ing that it was be­gin­ning to in­crease, he asked, “What o’clock is it?”

“One minute past five,” replied Gideon Spilett di­rect­ly. They had now on­ly to cal­cu­late the op­er­ation. Noth­ing could be eas­ier. It could be seen that there ex­ist­ed, in round num­bers, a dif­fer­ence of five hours be­tween the merid­ian of Wash­ing­ton and that of Lin­coln Is­land, that is to say, it was mid­day in Lin­coln Is­land when it was al­ready five o’clock in the evening in Wash­ing­ton. Now the sun, in its ap­par­ent move­ment round the earth, tra­vers­es one de­gree in four min­utes, or fif­teen de­grees an hour. Fif­teen de­grees mul­ti­plied by five hours give sev­en­ty-​five de­grees.

Then, since Wash­ing­ton is 77deg 3′ 11″ as much as to say sev­en­ty-​sev­en de­grees count­ed from the merid­ian of Green­wich which the Amer­icans take for their start­ing-​point for lon­gi­tudes con­cur­rent­ly with the En­glish–it fol­lowed that the is­land must be sit­uat­ed sev­en­ty-​sev­en and sev­en­ty-​five de­grees west of the merid­ian of Green­wich, that is to say, on the hun­dred and fifty-​sec­ond de­gree of west lon­gi­tude.

Cyrus Hard­ing an­nounced this re­sult to his com­pan­ions, and tak­ing in­to con­sid­er­ation er­rors of ob­ser­va­tion, as he had done for the lat­itude, he be­lieved he could pos­itive­ly af­firm that the po­si­tion of Lin­coln Is­land was be­tween the thir­ty-​fifth and the thir­ty-​sev­enth par­al­lel, and be­tween the hun­dred and fifti­eth and the hun­dred and fifty-​fifth merid­ian to the west of the merid­ian of Green­wich.

The pos­si­ble fault which he at­tribut­ed to er­rors in the ob­ser­va­tion was, it may be seen, of five de­grees on both sides, which, at six­ty miles to a de­gree, would give an er­ror of three hun­dred miles in lat­itude and lon­gi­tude for the ex­act po­si­tion.

But this er­ror would not in­flu­ence the de­ter­mi­na­tion which it was nec­es­sary to take. It was very ev­ident that Lin­coln Is­land was at such a dis­tance from ev­ery coun­try or is­land that it would be too haz­ardous to at­tempt to reach one in a frail boat.

In fact, this cal­cu­la­tion placed it at least twelve hun­dred miles from Tahi­ti and the is­lands of the archipela­go of the Po­moutous, more than eigh­teen hun­dred miles from New Zealand, and more than four thou­sand five hun­dred miles from the Amer­ican coast!

And when Cyrus Hard­ing con­sult­ed his mem­ory, he could not re­mem­ber in any way that such an is­land oc­cu­pied, in that part of the Pa­cif­ic, the sit­ua­tion as­signed to Lin­coln Is­land.