At noon they were on a broad stony platform, bare flat rock at the convergence of three mountain spurs, hot in the sun; and here their track could no longer be seen at all. Yet neither Eduardo nor his men seemed in any way concerned; they marched steadily across and turned right-handed where the westernmost spur ran down to the little plain, travelling steadily on through a sheltered and relatively fertile stretch of country, green here and there with tola bushes and shaggy with coarse yellow grass.
The going was easier, much clearer in direction and smoother by far. 'We have struck into one of the Inca post-roads,' said Eduardo, breaking the silence. 'In a little while, where there is marshy ground by day, it is paved. My ancestors may not have known the wheel, but they did know how to make roads. Beyond the marshy piece, where we may put up some wildfowl, there is a great tumble of boulders from an earthquake so long ago that they are covered with lichen, and not only lichen but a very curious woody fungus that I believe you may not have seen. It is called yaretta, and it grows at this height from here to the westward; and together with guanaco dung the heads make excellent firing. The rock-fall abounds with viscachas, and if we take our guns we may be spared guinea-pig for a great while: viscachas are capital eating. But Doctor, I am afraid you are sad. I am so sorry to have disappointed you of our altiplano rheas.'
'I am not at all disappointed, friend. I have seen a little flock of white-winged finches and a bird I took to be a mountain caracara.'
Eduardo was unconvinced. He looked into Stephen's face and said, 'Still, if only this weather holds' - glancing anxiously at the pure sky overhead - 'we should reach the pass in three days, and we will surely find wonders on my lake.'
On the morning of the second day the pass was clearly to be seen, a little above the snow-line between two matching peaks that soared another five thousand feet, brilliant white in the almost horizontal sun.
'There is the post-house,' said Eduardo, pointing his glass, 'just under the snow and a little to the right. It was built by Huayna Capac, and it is as strong as ever. The pass is high, as you see, but on the far side there is an easy road, downhill all the way to one of my brother's silver-mines and a village where they grow the best potatoes in Peru as well as corn and barley, and they breed excellent llamas - these animals all came from there, and that is one of the reasons that they step out so well. It is true that after that we have to cross a chasm, with the Uribu flowing far below, but there is a hanging bridge in quite good repair, and you do not dislike heights that fill weak minds with horror. Sailors pay no attention to heights - a circumnavigator is inured to prodigious heights. What have you found, don Esteban?'
'A curious beetle.'
'Very curious indeed. One day I shall really set myself to the study of beetles. My lake too is on the far side. It seems to me that we should reach the post-house in plenty of time for the men to settle in and for you and me to go on to my lake. At this time of year it will not even skim over with ice until well after sunset, and we may find ducks and geese by the hundred. We will take Molina, the best llama, to carry what we shoot.'
'If you are as mistaken about the birds as you are about my head for heights, Molina will have no great burden to carry, at all,' reflected Stephen, who had often heard, each time with deeper dismay, of the spidery Inca bridges upon which intrepid Indians crossed torrents raging a thousand feet below them, even hauling immobilized animals over by means of a primitive windlass, the whole construction swaying wildly to and fro as even a single traveller reached the middle, the first false step being the last.
'How long does it take to fall a thousand feet?' he asked himself, and as the troop set out he tried to make the calculation; but his arithmetical powers were and always had been weak. 'Long enough to make an act of contrition, at all events,' he said, abandoning the answer of seven hours and odd seconds as absurd.
On and on: up and up. This had been the pattern for a great while, but now the up and up was growing far more pronounced ; now it was often a question of leading his mule again; and now he had to concentrate his mind on keeping up wherever the road grew steep. His breath was coming short; his heart beat a hundred and twenty strokes a minute; his eyesight wavered.
'You are in a brown study, I find,' said Eduardo, whose spirits had revived with the altitude.
'I was contemplating on the physiology of animals that live in a rarefied atmosphere,' said Stephen. 'Surely the exact dissection of a vicuna would show some very remarkable adaptations?'
'There can be no doubt of it,' replied Eduardo. 'And at present we too mean to adapt our own persons for the last stretch with a draught of mate. Do you choose to dismount?'
Stephen did so, very carefully avoiding the least hint of unsteadiness. He could scarcely see, but he was most unwilling to show any sign of the mountain-sickness that had certainly come upon him. When his head cleared from the effort of swinging out of the saddle he looked up and saw to his relief that they were now quite near the snow-line, above sixteen thousand feet. He had never been so high, and he had every right to be mountain-sick: this was no discreditable weakness.
Already smoke was rising from the guanaco dung, the woody fungus heads and a few of those bushes that burned green; and presently the gourds of mate were passing round. Stephen drew in the hot cheering gusts through his silver tube, ate a dried peach from Chile, and then like all the rest he drew out his pouch of coca- leaves, preparing a moderate ball spread with quinoa ash, chewed it slightly to start the flow and then eased it into his cheek. The familiar tingling began almost at once, followed by the beginning of that curious numbness which had so startled him many years ago.
Mountain-sickness faded, anxiety with it; strength returned. He gazed at the climbing road, the last stretch, three steep traverses zigzagging up to the post-house, into the snow and over the pass. It would be walking every step of the way. He did not mind at all.
'Will you not ride, don Esteban?' asked Eduardo, holding the stirrup for him.
'No, sir,' said Stephen. 'The animal is extremely tired - look at his hanging lip, God be with him - whereas I am now quite recovered, a sprightly popinjay.'
A little less sprightly by the time they reached the massive post-house, built, like some of those sections of the road cut deep into the mountainside, of vast rocks so exactly shaped that they outstripped all reasonable conjecture, a little less sprightly, but perfectly human. He took the liveliest interest in the yaretta fungus growing on these rocks and on the inner walls, and Eduardo said to him, 'How glad I am to see you so brisk. Although we reached here in such good time I was afraid you might be too tired to see my lake. Do you think that after say an hour's rest you would like to go? There is some cloud in the east, and as you know winds sometimes get up in the evening; but an hour's rest would still leave us time.'
'Dear Eduardo,' said Stephen, 'the earlier we go the more we shall see. I fairly dote on alpine lakes, and this one as I recall has a fine fringe of reeds.'
It had indeed a fine fringe of reeds, a very fine deep fringe, unique in Stephen Maturin's extensive experience
