The Log of the Flying Fish Part 11

The party hurried below to the armoury, and each selected one of the weapons indicated by the professor, providing himself at the same time with a supply of cartridges from a large chest near at hand.

The rifles were truly formidable, being repeating weapons each capable of firing ten shots without reloading. The barrels were not very long, measuring only three feet from breech to muzzle, but they were of one- and-a-half-inch bore and fired a conical sh.e.l.l four and a half inches in length. Notwithstanding their somewhat ponderous appearance they were very light, being constructed of aethereum throughout.

When the party returned to the deck they had the satisfaction of seeing that, though each of the whale-boats had succeeded in fastening to a fish, the remainder of the school manifested very little alarm, the stricken whales having started to "run" in different directions and quite away from their companions.

The _Flying Fish_ was moved as gently as possible into the very centre of the herd, the huge monsters taking no apparent notice of her, and perhaps mistaking her for one of themselves. They were swimming lazily about, rolling over on their sides until their pectoral fins appeared above the surface, and occasionally throwing themselves entirely out of the water.

The engines being stopped the four sportsmen took up their positions, two on each side of the deck, and, having loaded their weapons, waited for a favourable opportunity to use them.

The baronet was the first to fire. He had selected for his victim a huge bull, fully eighty feet in length, and this creature he patiently watched, hoping for an opportunity to inflict a fatal wound. It soon came. The animal rolled lazily over on its right side, exposing the whole of its left fin, and before it could recover itself Sir Reginald had levelled and discharged his piece. There was a very faint puff of thin fleecy vapour, but no report or sound of any kind save the by no means loud click of the hammer, above which could be distinctly heard the dull thud of the sh.e.l.l. The whale shuddered visibly at the blow, and made as though about to "sound" or dive; but before it had power to do so the sh.e.l.l must have exploded, for the immense creature made a sudden violent writhing motion, half leapt out of the water, and rolled over on its side, dead. The professor scored the next success, closely followed by the colonel, Lieutenant Mildmay signalising his first essay with the new arm by making a palpable miss, much to his disgust. His failure, however, taught him a valuable lesson, and he succeeded in killing two whales before either of the others had been able to secure another shot. In ten minutes eight whales had been killed, and the professor, who was very rigid in his objection to the wanton sacrifice of life, then suggested that probably as many had been killed as the whaler could successfully deal with at one time, especially as the boats now had signals flying which showed that each had killed her fish. The _Flying Fish_ was accordingly ranged up close alongside the _Walrus_, and the baronet hailed:

"_Walrus_ ahoy! how many fish can you 'cut in' at one operation?"

"I wish I had the chance of trying my hand upon half a dozen," was the reply, given, the baronet thought, in rather a sulky tone.

"Well," returned Sir Reginald, "there are eight which we have killed and three taken by your boats, making eleven altogether. Can you handle any more? because, if so, we will kill them for you; but, if not, we think it best not to disturb them further."

"Do you mean to say that you've killed those fish on my account, then?"

asked Hudson with great animation.

"To be sure we did. You surely did not suppose that we wanted them for ourselves, did you?"

The whaling skipper muttered a few unintelligible words to himself, and then shouted back in unmistakably hearty tones:

"Thank'ee, gentlemen, thank'ee with all my heart. That's another favour I'm in your debt. That being the case, I think, if it's all the same to you, I'd rather that the rest of the school be left to go their ways in peace. I don't want them to be frightened; and eleven fish is as much as we can well handle at one time."

"In that case, then," returned Sir Reginald, "we will wish you 'Good- bye,' and a prosperous voyage."

"Thank'ee, gentlemen; the same to you, and best thanks for all favours,"

replied Hudson.

And with mutual hand-wavings and dipping of colours the two craft separated, the _Walrus_ bearing up to intercept her boats, and the _Flying Fish_ heading northward at a speed of about twenty knots.

For about a couple of hours the adventurous voyagers were able to maintain that speed; but toward noon they found themselves once more surrounded by ice; and they had no choice but either to materially reduce their speed and slowly thread their way through narrow and tortuous channels, or once more take flight into the air. They chose the latter alternative; and for the next two hours the flying ship sped northward through Smith's Sound, for the most part over an unbroken field of pack-ice which, to any ordinary vessel, would have opposed an utterly impa.s.sable barrier. At two o'clock in the afternoon, however, the Greenland sh.o.r.e suddenly trended to the north-eastward; and after following it for a short time the ice once more began to be intersected with water channels, short and narrow at first, but wider as they proceeded, until at length they found themselves once more able to descend in a water lane some four miles in width.

"And now," said the professor, as they were nearing a bold rocky headland on their starboard bow, "we are about to be introduced to one of _the_ sights _par excellence_ of the Arctic regions."

"What is it?" was the question which burst simultaneously from the lips of his three companions.

"Wait and see," answered the professor, nodding mysteriously.

Sure enough, the moment that the _Flying Fish_ rounded the point a magnificent spectacle burst upon the travellers' enraptured gaze. It was neither more nor less than an immense cliff of the clearest crystal ice, towering some three hundred feet above the water's edge, and extending so far northward along the coast that its northern extremity lay far below the horizon. It was the magnificent Humboldt Glacier.

The afternoon sun was shining full upon its rugged face, causing the enormous ma.s.s to flash and gleam like a gigantic diamond. As they coasted slowly along, at a distance of about half a mile from its face, the dazzling flashes of light were reproduced one after the other, changing rapidly from one colour to another through every conceivable tint of the rainbow, until the beholders' eyes fairly ached with the contemplation of so much splendour, all of which was reflected with the most charming variation in the mirror-like surface of the deep still water below. The wind had died away to a dead calm, as if to give the bold explorers an opportunity of witnessing this unrivalled sight to the best advantage; and every now and then the still air resounded with the sharp rifle-like _crack_ which told that, though apparently so motionless and solid, hidden forces were at work within the heart of the glacier, slowly but surely tending to its ultimate dismemberment.

Suddenly a crashing report, so loud that it resembled the simultaneous discharge of a whole army of rifles, smote upon their ears; and then, as they stood in a trance of breathless expectation, wondering what was about to happen, an immense section of the icy cliff was seen to be in motion. Slowly at first, but with ever-increasing rapidity, it slid downward into the water, with a continuous roaring reverberating crash, to which even the awful pealing of thunder was as nothing, until in a wild turmoil of madly leaping and foaming surges it disappeared entirely below the water. The sea rushed irresistibly after it from all sides, pouring like a foaming cataract into the hollow watery basin it had left, and dragging the _Flying Fish_ helplessly toward the yawning vortex. Then the inward rush suddenly ceased; a gleaming white crest of ice reappeared above the foam, and with a mighty upward rush and a resounding roar the gigantic submerged ma.s.s once more upreared itself above the again maddened waters, swaying heavily to and fro, whilst a thousand gleaming torrents poured down its sparkling sides. And, as a fitting _finale_ to the thrilling spectacle, a huge wall of water suddenly heaped itself up about the rocking ma.s.s and began to rush rapidly outward in an ever-widening circle, its towering crest surmounted by a roaring curling fringe of snow-white foam. Increasing in height and in speed as it advanced, it rapidly attained an alt.i.tude of fully sixty feet, bearing down upon the _Flying Fish_ so menacingly that, for a few seconds, the party in the pilot-house stood paralysed with consternation, expecting nothing less than that they would be helplessly overwhelmed. The first to recover his presence of mind was Mildmay, who, springing to the rods which controlled the air-valves, pressed them powerfully down, throwing them all wide open and at once ejecting from the hull both the water and the compressed air, and causing the ship to rise until she floated lightly as an air-bubble on the water. He then injected a dense body of vapour into the air and water chambers, completing the vacuum; and the ship rose into the air just in time to avoid the gigantic surge, which went hissing and roaring close beneath them with a power and fury which fully revealed to them the extent of the disturbance from which they had so narrowly escaped.

Other surges followed in quick rotation; but each was less formidable than its predecessor, and in another ten minutes the surface had once more subsided into a state of comparative calm.

As the _Flying Fish_ once more settled down upon the water and the air- pump was set going, the professor turned to his companions and remarked:

"We have especial reason to congratulate ourselves and each other, gentlemen, for we have to-day not only looked upon the magnificent Humboldt Glacier under most highly favourable conditions, but we have been also permitted to witness that even rarer sight, _the birth of an iceberg_!"

They had indeed witnessed the birth of an iceberg, and that too of quite unusual size; for, as soon as they dared, they approached the newly fallen ma.s.s of ice closely enough to make a tolerably accurate measurement of it; and they found that it was of nearly square shape, measuring fully three-quarters of a mile along each of its four sides, and towering to an average height of about three hundred and fifteen feet above the surface of the water. The visible portion of the berg const.i.tuted, however, only a small portion of its entire bulk, since fresh-water ice floating in salt water shows above the surface only one- eighth of its entire depth. This enormous berg, therefore, must have measured in its entirety about four thousand feet square by about two thousand five hundred feet deep! And its weight must have approximated closely upon two thousand millions of tons! Bergs of equal, or even greater dimensions, have occasionally been encountered in the Arctic seas; but how few of earth's inhabitants have ever been privileged to witness the disruption of so enormous a ma.s.s from its parent glacier!

After witnessing so thrilling a spectacle as this--probably the grandest and most impressive which the Arctic regions can exhibit--it is perhaps not to be wondered at that even the beauties of the glacier itself appeared somewhat tame and uninteresting to the voyagers. But their interest was once more awakened when, having at length coasted along the face of the glacier for a distance of not less than _sixty miles_, they reached its northern extremity and found the succeeding Greenland coast to be magnificently picturesque, the greenstone and sandstone cliffs in some cases towering abruptly from the water's edge to a height of a thousand feet or more, not in a smooth unbroken face, or even with the usual everyday rugged aspect of a rocky precipice, but presenting to the enraptured eye an ever-varying perspective of ruined b.u.t.tresses, pinnacles, arches, and even more fantastic architectural semblances. In one spot which caused them to pause in sheer admiration, the crumbling _debris_ at the foot of the cliff had shaped itself into the likeness of a huge causeway such as might have been constructed by one of the giants of fabulous times, leading into a deep wild rocky gorge rich in soft purple shadows, at the further edge of which rose a gigantic rock hewn by the storms of ten thousand winters into the exact similitude of a castle flanked by three lofty detached towers all bathed in the dreamy roseate haze of the evening sunshine. And, somewhat further on, they came to a single greenstone cliff the skyline of which was boldly chiselled into the likeness of the ruined ramparts of an extensive city, whilst at its northern extremity, at the edge of a deep ravine, a solitary column nearly five hundred feet high, and standing upon a base or pedestal nearly three hundred feet high, shot straight and smooth up into the deep blue of the northern sky.

Tearing themselves unwillingly away from this region of weird enchantment, the voyagers pushed onward along Kennedy and Robeson Channels, sometimes winding their way through intricate water lanes in the ice, and sometimes skimming lightly a few yards above the surface of the solid pack, until they reached the lat.i.tude of 82 degrees 30 minutes North, when the land abruptly trended away to their right and left, and they found themselves hovering over an immense field of pack-ice which extended in an unbroken ma.s.s as far northward as the eye could reach.

Up to the present, from the time of their pa.s.sing Disko Island, the voyagers had seen plenty of seals and walruses, with an occasional white bear, a few Arctic foxes, a herd or two of reindeer, and even a few specimens of the elk and musk-ox, to say nothing of birds, such as snow- geese, eider and long-tailed ducks, sea-eagles, divers, auks, and gulls.

Moreover, they had been favoured with, on the whole, exceptionally fine weather--due as much as anything, perhaps, to the fact that they had been fortunate enough to enter the Arctic circle during the prevalence of a "spell" of fine weather, and that they had accomplished in a very few days a distance which it would occupy an ordinary craft months of weary toil to cover. But, on pa.s.sing the edge of this gigantic ice barrier, they left all life behind them; even the very gulls--which had followed them in clouds whenever the speed of the _Flying Fish_ was low enough to permit of such a proceeding--after wheeling agitatedly about the ship for a few minutes with discordant screams, as of warning to the travellers not to venture into so vast and gloomy a solitude, forsook them and retraced their way to the southward. The weather, too, changed, the sky becoming overcast with a pall of dull grey snow--laden cloud accompanied by a dismal murky atmosphere and a temperature of ten degrees below zero. The wind sighed and moaned over the icy waste; but, excepting for this dreary and depressing sound, there was absolute silence, the silence of a dead world.

The ice bore at first the same appearance as all the other ice which they had hitherto encountered, but by the time that they had advanced a distance of thirty miles into the frozen desert they became conscious of a change. The hummocks were not so lofty as heretofore, the hollows between them having the appearance of being to a considerable extent filled up with hard frozen snow; the ice itself, too, instead of being a pure white, was tinged with yellow of the hue of very old ivory; the sharp angles, also, were all worn away as if by long-continued abrasion; the ice, in fact, bore unmistakable evidence of extreme age.

At the professor's suggestion a pause was made and a descent effected, in order that he might carefully investigate the nature of the ice; and, warmly clad in furs, the entire party left the ship for this purpose.

"It is as I feared," said von Schalckenberg, after they had toiled painfully over the surface for some time; "we have reached the region of paleocrystic or ancient ice; and my cherished theory of an open sea about the North Pole vanishes into thin air. Look at this ice here, where a portion of the original hummock still remains bare--it is yellow and rotten, not with the rottenness which precedes a thaw, but with extreme age. See, it crumbles at a kick or a blow, but the fragments do not melt; it is years--possibly _ages_--since this ice was water. And look at the edges of the blocks; they are rounded and worn away by the constant abrading action of the wind, the snow, the hail, and possibly the rain, which has beaten upon them through unnumbered years. It is no wonder that this is a lifeless solitude; there is nothing here capable of sustaining the life of even the meanest insect. Let us return to the ship, my friends, and hasten over this part of our journey; we shall meet with nothing worthy of interest until we reach the Pole, which itself will probably prove to be merely an undistinguishable spot in just such a waste as this."

The professor was, however mistaken; a most interesting discovery awaited them at no very great distance ahead. They returned to the ship oppressed with a vague feeling of melancholy foreboding for which they could not account, but which was doubtless attributable to the gloomy cheerless aspect of their surroundings, and, releasing the ship from the hold of her grip-anchors, resumed their way northward at the _Flying Fish's_ utmost speed.

Half an hour later, however, they suddenly checked their flight and diverged a mile to the eastward of their former course to examine an object which Mildmay's quick eye had detected. The object--or objects rather, for there were two of them--proved to be short poles or spars about twenty-five feet apart, projecting about twelve feet out of the ice, and surmounted by the skeleton framework of what seemed to have been at one time small bulwarked platforms. Wondering what they could possibly be, and by whom placed in so out-of-the-way a region, but thinking they might possibly mark cairns or places of deposit inclosing the records of some long-lost expedition, they resolved to stop and inst.i.tute a thorough examination.

They were fortunate enough to find a smooth and level spot suitable for grounding the _Flying Fish_ upon, at a distance of barely a quarter of a mile from the objects of their interest; and it being by that time six o'clock in the evening, and too late to do any good before dinner, they secured the ship there for the night--taking the precaution of fully weighting her down with compressed air in addition to mooring her firmly to the ice by her four grip-anchors. It was a most happy inspiration which impelled them to take this precaution; for when they arose next morning a terrific gale from the northward was blowing, accompanied by a heavy ceaseless fall of snow; and, well secured as the ship was both by her weight and by her anchors, she fairly trembled at times with the violence of the blast. Had she been dependent only upon her anchors and her own una.s.sisted weight--which the reader will remember was very trifling notwithstanding her immense dimensions--she would infallibly have been whirled away like a bubble upon the wings of the gale. The highly-compressed air, however, held her securely down upon her icy bed, and, beyond imparting an occasional tremor, as already mentioned, the tempest, fierce as it was, had no power to move her.

In such terrible weather it was of course useless to think of pursuing their investigations; it would, indeed, have been the sheerest madness to have attempted to face the furious gale, with its deadly cold and the blinding whirling snow. The travellers were therefore compelled to spend an inactive day. For this, however, they were by no means sorry; they had been keeping rather late hours since entering the Arctic circle, and this interval of inaction afforded them an opportunity of securing their arrears of rest. Besides this there were sketches to complete, and a thousand little odd matters to attend to--to such an extent, indeed, that when they once began work they wondered at their own thoughtlessness in not having attended to them before. Thus employed, with occasional interludes of meditative gazing out upon the ceaseless whirling rush of the snow, the day pa.s.sed rapidly and pleasantly away, wound up by an hour or two of vocal and instrumental music after dinner. They retired early to their warm comfortable state- rooms that night, and were lulled to sweet dreamless slumber by the howling of the gale outside.

The four following days were spent in the same manner--the gale lasting all that time with unabated fury, accompanied by an almost ceaseless fall of snow. But on the fifth day the weather moderated; the snow ceased, or at all events fell only intermittently; the wind backed round and blew from the south-west; and the exterior temperature, which during the gale had fallen to thirty-three degrees below zero, rose twenty degrees. The sky was still overcast and lowering, it is true, and the cold was still intense. But notwithstanding this the weather, compared with that of the preceding five days, seemed positively fine; and, wrapping themselves up in their warmest clothing, and arming themselves with pick and shovel, they set out to discover if possible what lay concealed beneath the two queer-looking poles.

CHAPTER ELEVEN.

AN INTERESTING RELIC.

They issued from the ship through the trap-door in her bottom; and no sooner did they find themselves in the open air than an almost uncontrollable impulse seized them to go back again. The contrast between the warm comfortable temperature of the ship's interior and the bitter piercing cold without was so great that at first the latter felt quite unendurable. They, however, persevered; and, after perhaps ten minutes of intense suffering, the severe exercise of scrambling over the rotten slippery hummocks somewhat restored their impeded circulation, and they began to feel that, perhaps, after all, they might be able to do something toward the execution of their self-imposed task. The mere act of breathing, however, continued to be exceedingly painful; and when they at length reached the spot of which they were in search, they were able to fully realise, for the first time in their lives, the incredible difficulties attendant upon the exploration of the regions within the polar circles.

On a nearer inspection of the two poles they proved to be stout spars about the thickness of a man's leg; and, from the appearance in each of a sort of sheave-hole, Lieutenant Mildmay declared his conviction that they were the masts of a small ship. They were very rotten, however, and, if Mildmay's surmise was indeed correct, the craft must have been under the ice for a very long time. The mere suggestion was enough to fully arouse their curiosity; and, forgetful for the moment of the intense cold, to which they were already in a measure growing accustomed, they set to work with a will plying pick-axe and shovel upon the ice with such small dexterity as they possessed.

The task to which they had devoted themselves was, after all, not a very difficult one, the ice, especially that of ancient formation, yielding readily before the vigorous strokes of their picks; and it soon became evident that they could work to greater advantage by dividing themselves into two gangs of two each; one gang breaking up the ice with the pick, and the other shovelling away the debris. The low temperature, however, made the work very exhausting; and by lunch time they had only succeeded in excavating a hole some twenty-five feet long--or the distance between the two masts--by six feet wide and four feet deep. They had widened this excavation by a couple of feet and sunk it some four feet deeper by six o'clock that evening; and then they knocked off work for the day, returning to the _Flying Fish_ stiff, and exhausted with their unwonted exertions, but with more voracious appet.i.tes than they ever remembered experiencing before.

In this way they laboured day after day for ten days; being greatly hindered in their operations by frequent showers of snow, which filled up their excavation almost as rapidly as they made it, until, beginning to lose patience at their slow progress, they resolved to run a little risk, and the professor was induced to employ a minute portion of his explosive compound in blowing away the sides of the pit to a sufficient extent to allow of the snow drifting out with the wind instead of lodging in the bottom. This engineering feat was successfully accomplished without apparent damage to the object they sought to bring to light; and, thus encouraged, they further cautiously employed the compound in breaking up the ice, with the triumphant result that, on the evening of the thirteenth day before giving up work, they succeeded in uncovering the deck of a craft measuring eighty feet long over all by sixteen feet beam. They were now intensely excited and elated, as they had every reason to believe that--judging from certain peculiarities of build which had already revealed themselves--they had discovered a most interesting relic.

The next morning was most fortunately as fine as they could reasonably expect it to be in that stormy and desolate region; and, commencing work at an early hour--having, moreover, by this time acquired quite a respectable dexterity in the use of their tools--they succeeded by lunch time in laying completely bare the entire hull of what proved most unmistakably to be a veritable ancient Viking ship.

This intensely interesting relic was, as already stated, eighty feet long by sixteen feet beam; with a depth of hold in midships, as they now found, of eight feet; she must therefore have been at the time of her launch quite a n.o.ble specimen of naval architecture. She was of course built of wood, and was beautifully moulded fore and aft; her stem and stern-posts were carried to a height of five feet above her rail; and the former was finished off with a rather roughly hewn but vigorously modelled horse's head, whilst the latter terminated in an elaborately carved piece of scroll-work. She was fully decked, with a sort of monkey-p.o.o.p aft, about two and a half feet high and twenty feet long, beneath which was her princ.i.p.al cabin. Her bulwarks and rail were very solidly constructed; the former being pierced with rowlock holes for sixteen oars or sweeps of a side, in addition to holes abaft, one on each side of, and near the stern-post, for the short broad-bladed steering paddles. Both of these paddles, together with twenty-three oars and two square sails, shaped somewhat like lugs and still attached to their yards, were found stowed fore and aft amidships on the vessel's deck. They were all in an excellent state of preservation, as were also the lower portions of the masts; indeed it was only that portion of these spars which had been long exposed to the air which showed signs of rot, the upper extremities being most rotten, whilst the parts close to the deck were perfectly sound.

Having fully satisfied their curiosity with regard to the exterior of this interesting craft, they next essayed to penetrate below by forcing open the after hatch. On removing the cover a small and almost perpendicular ladder was revealed, down which Mildmay rapidly made his way. On reaching the bottom he found himself in a small vestibule or ante-room, the floor, sides, and ceiling of which were thickly cased with smooth gla.s.sy ice, long icicles of varying thicknesses also depending from the beams and deck planking overhead. He could trace the existence of a door in the middle of the bulkhead facing him; but it was hermetically sealed with the thick coating of ice before mentioned, and the removal of this occupied over half an hour. Whilst he was thus engaged the rest of the party at his suggestion returned to the _Flying Fish_ for the small electric lamps used in their diving operations; and when they returned he was just about ready to force open the door of the after cabin. This was accomplished without much difficulty, and a faint sickly odour at once became apparent, issuing from the interior of the cabin.

Consumed by curiosity, the party pressed eagerly forward through the doorway, and a most extraordinary sight at once revealed itself. The cabin was a tolerably roomy apartment for the size of the vessel, having for furniture a solid handsomely carved oaken table in the centre, shaped to suit the narrowing dimensions of the vessel abaft, and side benches or lockers all round the sides. The walls or inner planking of the ship were thickly covered with seal, walrus, and white bear skins, evidently hung there to prevent, as far as possible, the penetration of the extreme cold through the ship's sides; and upon large nails, driven through these and into the planks, were hung various trophies of weapons, such as long two-handed swords, small shields or targets, maces with heavy iron-spiked heads, short-handled battle-axes, spears, unstrung bows, and quivers of arrows. But it was not these objects, interesting as they were, which first riveted the attention of the intruders; it was upon _the occupants of the cabin_ that their startled glances fixed themselves. Yes, strange as it may seem, the four nineteenth-century travellers found themselves face to face with some at least of the hardy crew who had stood on the deck waving their last good-bye to wives, children, or sweethearts--who shall say how many years ago?--when that stout galley swept out of harbour with pennons flying, oars flashing, and arms glancing, maybe, in the brilliant sunshine, as she started on the enterprise of wild adventure from which she was never to return. The inmates were four in number. Three of them were reclining on the lockers, their heads pillowed upon, and their bodies thickly covered with skins, whilst the fourth, doubtless the master spirit of the expedition, sat as in life at the narrow or after end of the table, his body supported in a ma.s.sive quaintly carved oaken chair.

The bodies, the floor, the table, and every article in the cabin were thickly coated with frost-rime, which glittered with a diamond-like l.u.s.tre in the cold keen light of the electric lamps, and the first act of the visitors was to carefully remove and clear away this frost coating. To their intense satisfaction this task was accomplished by gentle brushing without the slightest difficulty, and they were then able to minutely inspect the bodies of these ancient sea kings. They were in a state of surprisingly perfect preservation, and indeed had the appearance of having only recently fallen asleep, the intense cold having seized upon them with such fierce rapidity that their bodies had completely congealed before even the primary stages of decay had had time to manifest themselves. Indeed, judging from appearances, they had succ.u.mbed, in the first instance, to starvation, and, overcome by weakness, had been frozen to death. They were all of lofty stature and muscular build, with fair hair and tawny beards and moustaches, the latter worn extremely long. They were fully clad, all in garments of the same general character, excepting that those of the seated figure appeared to be of somewhat finer material than those of his companions.