CHAPTER TWENTY SEVEN.
THE SNOW-LINE.
"In three days the cart was finished. We had no difficulty inconstructing one, as the principal part--that is, the wheels--wasalready made. We had two pair of them, of course, in our old wagon; andthe larger ones, which happened to be in very good order, served ourpurpose exactly. Cudjo soon attached a body and shafts to them, andPompo's harness was put into thorough repair.
"We had not long to wait for a fine day. Every day was fine in theclear, pure climate of our valley; so that, as soon as the cart wasready, we had a day to our liking.
"We set out shortly after sunrise, with our hearts full of anticipatedpleasure. Of course we all went--Mary, the children, Cudjo, Pompo,dogs, and all. The house was again left to take care of itself. Maryand the two little ones rode in the cart, upon a soft seat made ofpalmetto leaves and Spanish moss. Pompo, who appeared to partake of thegeneral happiness, whisked the vehicle along as if there had been nobodyin it, and he was only drawing it for his own amusement. Cudjo crackedhis great wagon-whip, and every now and then uttered a loud `wo-ha;'while Castor and Pollux galloped gaily from side to side, running theirnoses into every bush that grew near the path.
"We soon made our way through the valley, and climbed up to the plain.We looked once more upon the Desert that stretched away on all sides;but its dreary aspect no longer filled us with fear. We did not regardit now, and the sight inspired us with feelings of curiosity and noveltyrather than of terror. Away to the southward the sun was glancing uponthe broad expanse of white sand; and several tall objects, like vastdun-coloured towers, were moving over the plain. They were whirlwindscarrying the dust upward to the blue sky, and spinning it from point topoint. Sometimes one glided away alone, until it was lost on thedistant horizon. Here two of them were moving in the same direction,keeping a regular distance from each other, and seemingly running arace. There several came together; and, after a short gusty contest,the whole set would break up into shapeless masses of yellowish clouds,and then float onward with the wind, and downward to the earth again.It was an interesting sight to view those huge pillars towering up tothe heavens, and whirling like unearthly objects over the wide plain.It was indeed an interesting sight, and we remained for many minutesobserving their motions.
"At length we turned our faces toward the mountain, and continued ourjourney along the edge of the cliffs. The high peak glistened beforeus, and the sun's rays falling upon it caused it to appear of abeautiful colour--a mixture of gold and red, as though a shower of roseshad fallen upon the snow! We noticed that there was now more snow uponthe mountain than when we had first seen it, and that it came fartherdown its sides. This attracted the attention of all of us; and Frank atonce called for an explanation, which his mother volunteered to give,for she very well understood the phenomenon.
"`In the first place,' said she, `as you ascend upwards in theatmosphere, it becomes thinner and colder. Beyond a certain point it isso cold, that neither men nor any other animals can exist. This can beproved in several ways; and the experience of those who have climbedmountains, only three miles high, confirms it. Some of theseadventurous men have been nearly frozen to death. This is a fact, then,in regard to the atmosphere over all parts of the earth; but we may alsoobserve, that under the Equator you may go higher without reaching thisextreme cold, than in the countries which lie nearer to the Poles.Another fact, which you will easily believe, is, that in summer you canclimb higher before you reach the cold region than in winter. Bearthese facts in mind. Now, then, if it be so cold at a certain heightthat men would be frozen to death, of course at that height snow willnot melt. What is the natural inference? Why--that mountains whosetops pierce up into this cold region will most certainly be covered withperpetual snow. It is not likely that anything but snow ever falls upontheir summits,--for when it rains upon the plains around them, it issnowing upon the high peaks above. Indeed, it is probable that most ofthe rain which descends upon the earth has been crystals of snow when itcommenced its descent; and, afterwards melting in the lower and warmerregions of the atmosphere, takes the shape of water globules, and thusfalls to the ground. These globules, no doubt, are very small when theyfirst emerge from the snow region; but, as they pass slowly downwardthrough clouds of vapour, they gather together and attract others (by alaw which I have not time to explain); and, descending faster andfaster, at length plash down to the earth in large drops. Whenever itrains, then, at any particular place, you may be almost certain that itis snowing at the same time over that place--only at a point in theatmosphere far above it. I have been convinced of this fact, byobserving that immediately after every occasion when it has rained inthe valley, there appeared a greater quantity of snow upon the mountain.Had the mountain not been there, this snow would have continued on, andbecome rain, like that which fell upon the plains, and into the valley.'
"`Then, mamma,' interrupted Frank, `this mountain must be of greatheight, since the snow lies upon it all the year.'
"`Does that follow?'
"`I think so. You said the snow did not melt because it was cold highup.'
"`But suppose you were in a country near the North Pole, where snow liesall the year at the very sea-side, and consequently at the sea-level,would it then prove a mountain to be very high?'
"`Oh! I see--I see now. The perpetual snow upon a mountain only showsit to be of great height when the mountain happens to be in warmlatitudes.'
"`Precisely so. In very warm countries, such as those within thetropics, when you see the snow-cap upon a mountain, you may infer thatit is a very high one--at least over two miles in height; and when thereis much snow upon it--that is, when the snow reaches far down itssides--it proves the mountain to be still higher,--three miles or moreabove the level of the ocean.'
"`Our mountain, then, must be a high one, since it is in a warmlatitude, and snow lies all the year upon it.'
"`It is a high one, comparatively speaking; but you will remember, whenwe first saw it, there was only a small patch of snow upon its top, andprobably in very hot summers that disappears altogether; so that it isnot so high as many others upon this continent. Taking our latitudeinto calculation, and the quantity of snow which lies upon thismountain, I should say it was about 14,000 feet.'
"`Oh! so much as that! It does not seem half so high. I have seenmountains that appeared to me to be quite as high as it, and yet it wassaid they did not measure the half of 14,000 feet.'
"`That arises from the fact that you are not viewing this one from thesea-level, as you did them. The plain upon which it stands, and fromwhich we view it, is of itself elevated nearly half as much. You mustremember that we are upon one of the high tables of the Americancontinent.'
"Here, for a minute or so, the conversation stopped; and we travelled onin silence, all of us with our eyes fixed on the white and roseate peakthat glittered before us, leading our eyes far up into the heavens.
"Frank again resumed the discourse, which had been broken off by ouradmiration of this beautiful object.
"`Is it not curious,' said he, `that the snow should lie so regularly,coming down on all sides to the same height, and ending just like thecape of a coat or the hem of a nightcap? It seems to be a straight lineall around the mountain.'
"`That line,' rejoined his mother, `is, as you say, a curiousphenomenon, and caused by the laws of heat and cold, which we have justbeen explaining. It is called the "snow-line," and a good deal ofspeculation has arisen among cosmographers about the elevation of thisline. Of course, on mountains within the tropics this line will be at agreat height above the level of the sea. As you advance northward orsouthward to the Poles, it will be found lower and lower, until withinthe frigid zones it may be said to cease altogether--for there, as wehave said, snow covers the whole earth, and there can be no "snow-line."
"`From this, one would suppose that an exact scale might be formed,giving the elevation of the snow-line for all latitudes. But that cou
ldnot be done. Observation has shown that it not only differs onmountains that lie in the same latitude, but that on the same mountainit is often higher on one side than the other--particularly on those ofgreat extent, as the Himmalehs of India. This is all quite natural, andeasily accounted for. The position of mountains to one another, andtheir proximity or great distance from the sea, will give them a colderor warmer atmosphere, independent of latitude. Moreover, the samemountain may have a warmer climate on one side than the other; and ofcourse the snow-line will be higher on that side which is the warmer, inconsequence of the greater melting of the snow. This line, too, variesin summer and winter for a like reason--as we see here upon our ownmountain, where it has already descended several feet since the weatherbecame colder. This, you will acknowledge, is all very natural; and youwill see, too, that Nature, although apparently capricious in many ofher operations, acts most regularly in this one, as perhaps in allothers.'
"`But, mamma,' inquired Harry, `can we not get to the top of themountain? I should like to have some snow to make snow-balls, and peltFrank with them.'
"`It would be a very difficult task, Master Hal; and more than eitheryou or I could get through with. I think Frank will escape beingsnow-balled this time.'
"`But people have climbed to the top of the Himmaleh mountains; and theyare far higher than this, I am sure.'
"`Never,' interrupted Frank; `no one has ever climbed the Himmalehs.Have they, mamma?'
"`No mortal has ever been so high as the summits of those greatmountains, which are more than five miles above the level of the ocean.Even could they be climbed, it is not likely that any animal could liveat their top. These inaccessible things seem to have been designed bythe Creator to afford us objects for sublime contemplation--objects farabove the reach of mortal man, and that can never be rendered common byhis contact. Do they not seem so?'
"We had now reached the foot of the mountain, and halting near theentrance of the ravine, we loosed Pompo from his cart, and restedourselves on the banks of the little stream. After a while we commencedascending up into the defile in search of the pinons. As we advanced,Mary pointed out the trees which she had noticed on a former occasion.They appeared of a light green colour, much lighter than others thatgrew near them. We made towards one which stood apart, and was mostaccessible to us. This we hoped might prove to be the bread-pine tree;and we approached it with feelings of anxiety and expectation.
"In a short time we were under its branches; and if we had had no othertest than what we saw there, combined with the delicious fragrance ofthe tree, we could have told that it could be no other than the pinon.The ground was covered with cones, each of them about an inch and a halfin length; but on examining them, we found them all broken open and theseed extracted. Some animal had been there before us, and relishedtheir contents--thus affording a proof that they were good to eat.There were still many of the cones hanging on the tree; and it was notlong until we had split some of them open and tasted their ripe seeds.
"`It is it!' cried my wife, clapping her hands with delight. `It is thenut-pine! This will serve for bread until we can grow our wheat andcorn. Come, let us gather them,' added she, pointing to a large groveof the same trees that grew at a short distance; and we all hurried tothe grove, and commenced shaking down the cones and gathering them intoheaps.
"We had soon collected as many as we wanted, and in the evening wereturned to the valley, with our little cart half-full of pine-nuts. Onreaching home, some of them were parched and pounded into a sort ofcoarse meal; and that night, for the first time during many weeks, wehad cakes to our supper.