Chapter XV
General description of Tibet—Systems of mountains—Trans-Sutlej Himalaya—Cis-Sutlej Himalaya—Kouenlun—Four Passes across Kouenlun—Boundaries of Western Tibet—Height of its mountain ranges and passes—Climate of Tibet—Clouds—Winds—Snow-fall—Glaciers—Their former greater extension—Elevation to which they descend—Snow-level—Geology—Lacustrine clay and alluvium.
The elevated country of Central Asia, situated to the north of the lofty snowy mountains which encircle India from Kashmir to Assam, is familiarly known to Europeans by the name of Thibet or Tubet,—most properly, I believe, Tibet. This name is also commonly employed by the Mohammedan nations to the north and west to designate the same country, but is not, so far as I am aware, known in the language of the Tibetans themselves, among whom different portions of the country are usually known by different names.
BOUNDARIES OF TIBET.
The whole of Tibet (as far as our present very limited knowledge of the south-east portion enables an opinion to be formed) appears to be characterized by great uniformity of climate and productions, and perhaps also of natural features, on which account it appears convenient to retain the name for the whole country, although, as has already been pointed out by Baron Humboldt28, it is naturally separable into two grand divisions. One of these, the waters of which collect to join the Sanpu, which in India becomes the Brahmaputra, is still scarcely known; the other, drained principally by the Indus and its tributaries, has been repeatedly visited by European travellers. The line of separation between these two portions lies a little to the east of the great lakes29, from the neighbourhood of which the country must gradually slope in both directions towards the sea.
If the whole of western Tibet formed (as it does, according to the popular opinion on the subject of the countries to the north of the Himalaya) an extensive plain bounded on the south by the great chain of the Himalaya, and on the north by the lofty mountains of Kouenlun, it would be an easy task to define its limits. This is, however, so far from being the case, that the greater part of the surface of the country is traversed in all directions by ranges of mountains in every respect similar to the Himalaya, of which in fact those south of the Indus are ramifications, while those on the north are branches of the snowy chain of Kouenlun.
If, again, the Himalaya formed an uninterrupted chain along the southern border of Tibet, broken only by the passage of the Indus at one extremity and by that of the Brahmaputra at the other, the mountainous nature of the interior would be no obstacle to the existence of a clear and distinct boundary. Unfortunately, however, for simplicity of definition, no such chain exists. A line of high snowy peaks may doubtless be traced in a direction nearly parallel to the plains of India, but these are separated from one another by deep ravines, along which flow large and rapid rivers, and therefore afford no tangible line of demarcation between the two countries.
TRANS-SUTLEJ HIMALAYA.
Between the river Indus and the plains of north-west India is interposed a mountain tract which has a breadth of about 150 miles in linear distance. This tract is everywhere (with one exception) extremely rugged and mountainous, nor is it at all an easy task to convey an idea of the extreme complication of the ramifications of the numerous ranges of which it consists. No wide plain (Kashmir alone excepted) is interposed between these ranges, so that the only feasible mode of division which appears to be applicable to them is afforded by the course of the different rivers which traverse them in various directions. If these be taken as a guide, the mountains will be found to resolve themselves into two great systems connected to the eastward, but otherwise independent of, though nearly parallel to, one another.
From the sources of the west branch of the Chenab or Chandrabhaga river, a range of very great elevation runs in a north-west direction as far as Kashmir, and, after reaching the north-east corner of that valley, assumes a more westerly direction so as to encircle the whole of its north side, bending at the same time gradually towards the south. This chain forms the line of separation between the waters of the Indus and those of the Chenab and Jelam. To the eastward of the Baralacha Pass it ramifies to a considerable extent, its different branches including between them several depressions quite unconnected with the general drainage of the country, and surrounded on all sides by ranges of hills which prevent any exit of their waters. The principal of these depressions is that of lake Chumoreri; another is occupied by the little salt lake first visited by Trebeck, and called by him Thogji30.
SALT LAKES.
All these depressions, though at present unconnected with any of the river systems, have evidently at some former period been so. Chumoreri, as I am informed by Major Cunningham, is even now very slightly saline, though scarcely perceptibly so to the taste. It has evidently had an outlet at its southern extremity, where it is only separated from the valley of the Parang river by a very low range of hills which was crossed in 1846 by Mr. Agnew, and more recently by Captain H. Strachey. The outlet of the little salt lake of Thogji has evidently been near its north end, and its waters, previous to the change in the state of the country which interrupted their exit, in all probability flowed into that tributary of the Zanskar river which runs to the eastward of the Lachalang pass, and which is marked in the map accompanying Moorcroft’s Travels as the Sumghiel. Major Cunningham, who travelled in 1846 by the same route as that previously followed by Moorcroft, informs me that no obstacle intervenes to prevent the waters of the lake taking that direction in case of their being raised in the lake itself to a height of two or three hundred feet above their present level.
If we consider the basins of these two lakes to be referable to the systems of drainage to which they appear to have formerly belonged, though now separated from them by accidental alterations of level, the course of the mountain chain which I am endeavouring to trace must be considered to run between the two. This is in fact the position of the loftiest part of the chain, which, skirting the north and east sides of Chumoreri, is thence continued in a south-east direction, forming that lofty but little-known range which separates the valley of the Sutlej from that of the Indus. This chain was crossed by Moorcroft on his visit to Garu, and appears to extend uninterruptedly as far as Kailas to the north of lake Manasarawar.
The mountain chain which lies to the south of the river Sutlej may also be considered to have its origin in the lofty country adjoining the lakes, but a little to the south and east of them. This chain, which separates the valley of the Sutlej from that of the Ganges and its tributaries (including the Jumna), sinks at last into the plains of India a little to the south of the town of Nahan.
CIS-SUTLEJ HIMALAYA.
The course of this chain has been admirably described by Captain Herbert in his Geological Report of the Himalaya31, a paper which contains exceedingly accurate general views of the mountains between the Sutlej and Jumna. He was quite unacquainted with the details of the mountains north of the former river, and therefore could not form any idea of their arrangement. Captain Herbert calls the chain south of the Sutlej the Indo-Gangetic chain, a very inappropriate name, for which, however, it is difficult to substitute a better. Perhaps the name of Cis-Sutlej Himalaya, though not exactly classical, is the best that can be devised, and if so, the chain which, commencing in Kailas, separates the waters of the Sutlej from those of the Indus, may not improperly be designated the Trans-Sutlej Himalaya32.
To these two great chains the whole of the mountains between the Indus and the plains may be referred. Both are of very great elevation, in the eastern half of their course more especially, but that north of the Sutlej is much less covered with snow than the other. This is owing to the moisture-bringing winds, which are entirely derived from the Indian side, being stopped by the chain to the south; and in fact, as soon as the elevation of the latter is so far diminished that it ceases to be covered with perpetual snow, the more northerly chain, without any increase of elevation, becomes much more snowy, so as to merit the appellation of great snowy range, a term which, more to the eastward, is applied to the mountains south of the Sutlej. As several of the principal ramifications of the northern chain attain an elevation not at all inferior to that of the axis from which they are derived, they produce a similar effect upon the climate of the ranges to the north of them, being themselves covered with vast masses of snow, while the mountains which they shelter are in a great measure bare.
KOUENLUN.
The northern boundary of Tibet is formed by the great chain north of the Indus, to which Humboldt, following Chinese geographers, has given the name of Kouenlun. Our knowledge of the appearance and course of this chain of mountains, by which Tibet is separated from Yarkand and Khoten, is so extremely limited that, except as to its general direction, very little can be said regarding it. The only conclusion which can be drawn from the scanty notices of it by travellers is, that it must be of extreme height and covered with perpetual snow. Many of the principal ramifications which it sends down towards the Indus are very elevated, and immense glaciers descend in their valleys, so that, except in a very few places, the main chain cannot be seen from the valley of the Shayuk, the mountains in the immediate vicinity of that river in general obstructing the view.
PASSES ACROSS KOUENLUN.
I am not aware of more than four places in which passes exist across the Kouenlun. The most westerly of these, called in Balti the pass of the Muztagh, lies at the source of the right branch of the Shigar river, a stream which joins the Indus opposite the town of Iskardo. The road over this pass to Yarkand was formerly frequented by merchants, but has for many years been disused, the reason assigned being the danger of plunder by the hordes of robbers beyond. As described to me by persons who had crossed it, the snow is reached after ten days’ journey from Iskardo, and continues during three marches. It is said to be quite impracticable for horses, from which it may, I think, be inferred that there are numerous glaciers.
The second pass is that marked in Vigne’s map as the Alibransa pass, at the head of a considerable tributary which joins the Shayuk river opposite Khapalu. The enormous glacier over which this road runs, by which, in conjunction with the lateness of the season, Mr. Vigne’s attempts to cross the pass were frustrated, has been well described by that traveller33. I did not, while in Tibet, meet with any one who had crossed it, and I was assured by the inhabitants of Nubra that they were not acquainted with any road from the upper part of their valley, either towards Khapalu or towards Yarkand.
The third pass, and the only one now frequented, is that of the Karakoram, an extremely easy though very elevated one. The most easterly pass of which I find any notice occurs on the road between Ruduk and Khoten; it is mentioned by Moorcroft34, but without any account of the nature of the road, or the elevation of the mountains.
To the westward of Karakoram, the direction of the Kouenlun is seemingly as nearly as possible parallel to the Indus, but to the east of that pass nothing certain is known regarding it. In Humboldt’s map it is laid down as running nearly from west to east, on the authority of Chinese geographical works. Its course is unquestionably to the north of the Pangong lake, but till it has been explored by European travellers its direction must, I think, be regarded as involved in much doubt. Another lofty range, however, unquestionably runs parallel to the Indus from south-east to north-west. This range, which is continuous with that by which the Indus and Shayuk rivers are separated, terminates (or more properly originates) in the still almost unknown mass of mountains which lies to the north of lake Manasarawar. Between this chain and the Kouenlun is situated a tract of country of unknown extent, which seems to be made up of a number of isolated lake-basins quite unconnected, not only with one another, but with the general drainage of the country by which they are surrounded.
PANGONG LAKE.
If we except the basin of the Pangong lake, into which Moorcroft and Trebeck descended after crossing the range of mountains parallel to the Indus, every part of this country must be viewed as a terra incognita. It cannot, I think, be doubted, from the description of the Pangong lake given by Moorcroft and Trebeck, that the basin in which it rests had originally an outlet at its north-west extremity, discharging itself along the valley of Tanktse into the Shayuk. The country to the eastward is so totally unknown, that it is impossible to conjecture whether the little lake-basins of which it is said to consist, discharge themselves towards the Pangong lake, or southward into the Indus.
BOUNDARIES OF TIBET.
Western Tibet, then, is a highly mountainous country, lying on both sides of the river Indus, with its longer axis directed like that river from south-east to north-west. It is bounded on the north-east by the Kouenlun chain of mountains, by which it is separated from the basin of Yarkand. On the south-east its boundary is formed by the ridge which separates the waters of the Indus from those of the Sanpu. To the north-west and south-west its boundaries are somewhat arbitrary, unless the political division of the country be had recourse to, which, depending on accidental circumstances entirely unconnected with physical geography or natural productions, is so liable to change, that its adoption would be extremely inconvenient. The best mode of drawing a line of separation between India and Tibet, in those parts where mountain chains are not available for the purpose, appears to consist in regarding the latter to commence only at the point where the aridity of the climate is too great to support forests of trees, or any coniferous tree except juniper.
As limited by these boundaries, West Tibet includes the whole of the valley of the Indus and its tributaries, down to about 6000 feet above the level of the sea, a considerable portion of the upper course of the Sutlej down to between 9000 and 10,000 feet, and small portions of the upper course of the Chenab, of the Ganges (Jahnavi), and of the Gogra.
MOUNTAIN RANGES.
Every part of Tibet is traversed by ranges of mountains which have their origin either in the Kouenlun on the north, or in the trans-Sutlej Himalaya on the south. These mountain ranges are generally extremely rocky and rugged, but as a general rule it may be said that they are less so in the upper part of the course of the different rivers, than in their lower parts. This rule applies not only to the Indus and to the Sutlej, but with scarcely an exception to all the tributaries of these rivers. There are no extensive open plains in any part of the country, the only level portions being in the valleys of the rivers, the width of which is usually not more than one or two miles, and very seldom exceeds five miles.
To this general description of the surface of the country I have met with no exception in those parts of Tibet which I have had an opportunity of examining. I have not, however, had an opportunity of seeing the extreme south-west portion, my knowledge of the course of the Indus not extending further up than Hanle35.
The height of the mountain ranges which traverse West Tibet is in all parts pretty much the same, and, as a consequence, the depth of the valleys in the lower portion of the course of the Indus and of all its tributaries is very much greater than near the sources of these rivers. In the higher valleys therefore the mountains are apparently much less lofty; they are also frequently rounded and sloping, or at all events less rocky and precipitous than lower down, though to this there are many exceptions.
ELEVATION OF PASSES.
The elevation of the passes in a mountainous region represents in general the height of the lowest part of the chain. In the mountain ranges of Tibet the average height of the ridges does not exceed from 1000 to 2000 feet above the passes, many of which indeed are scarcely at all lower than the highest crest of the ridge in which they are situated. I believe that in estimating the principal ranges of mountains at 19,000 feet, and the minor ranges at from 17,000 to 18,000 feet, I approximate very closely to the truth. This estimate applies to all parts of the country, the height of the ranges being remarkably uniform; but peaks occur at intervals in every one of the principal mountain ranges, which considerably exceed the elevation just stated, rising very generally (so far as can be judged by the eye from known heights of 17,000 and 18,000 feet) to twenty-one or twenty-two thousand feet; some peaks appearing to exceed even this.
It is generally supposed that the great peaks of the Himalaya on the southern border of Tibet are much more lofty than the mountains of the interior of that country. I do not think, however, that the facts of the case are such as to warrant this assumption. West of the Sutlej, in which district only the mountains of Tibet may be said to be at all known, many peaks of the interior of that country are probably much more lofty than any of those near the plains of India, and if inaccessibility is to be any criterion, the chain of the Kouenlun is beyond a doubt a much more elevated mass than any part of the Western Himalaya. Of Tibet east of the Sutlej little is known, except that between Ruduk and Lassa no road into the interior of Asia appears to exist.
CLIMATE.
The climate of Tibet is in every part extremely arid, because it is surrounded almost entirely by ranges of mountains so elevated that the rarefied air which passes over them can contain only a very small proportion of aqueous vapour. Along the Indus, indeed, no mountain chains are interposed to obstruct the passage of moist air, but the lower course of that river lies entirely in a comparatively dry climate, so that the winds which blow over the plains of Sind and the lower mountains of Eastern Affghanistan cannot convey any excess of moisture to lower Tibet. In the few Tibetan valleys which, like that of the Sutlej, are traversed by rivers debouching on the plains of India in a rainy climate, the quantity of moist air which they can receive being limited to that which proceeds directly up the valley, the upward current, even when saturated with moisture at the commencement, being gradually rarefied by the increasing elevation of the river-bed, and meeting with descending currents of cold air in its course, it very early deposits its moisture, first in the form of light showers, afterwards of fog and mist, and in its further progress is just as dry as the air in the more interior parts of the country.
RAIN-FALL.
It will probably be long before lengthened registers of meteorological phenomena will be obtained from all the different stages between India and the central parts of Tibet, so as satisfactorily to establish the gradual transition of climate. Till such shall be the case, the best evidence from which to deduce the fact of the alteration of climate, is afforded by the gradual change in the vegetation of the country as one advances towards the interior. Direct observation will probably at some future period fix the point in the outer Himalaya, at which the quantity of rain—always greater, cæteris paribus, among mountains than in level countries—is a maximum. I believe that in the Western Himalaya the greatest quantity of rain will be found to fall on mountains elevated from seven to nine thousand feet. Ranges of mountains which attain an elevation of from ten to eleven thousand feet have already (in the Western Himalaya) a very sensible effect in diminishing the quantity of moisture, as indicated by the vegetation; and when the mountain chains became sufficiently elevated to be capped by perpetual snow, they condense a very great proportion of the moisture of the air-currents which pass over them.
To a traveller who penetrates directly to the Tibetan interior from the plains of India, the change of climate is perceptible to the senses; most markedly so of course if his journey occurs during the Indian rainy season. Even during the rains, however, the irregularities which everywhere occur in the fall of rain prevent the gradations of climate from being ascertained during a journey with the precision which a lengthened series of observations would permit; but the phenomena of vegetable life, which are dependent on the average seasons, are not affected by accidental irregularities, and therefore form an unerring guide.
CLOUDS.
Though the climate of the whole of Western Tibet may, in general, be characterized as extremely dry, it is by no means cloudless. The winter months in particular are often very cloudy, and a good deal of snow falls. During the summer the sky is either bright and clear, or overcast with very light clouds. These clouds, usually cirrhi, are in general elevated and extremely thin. The cirrhus, when it remains for any length of time, changes or increases into a uniform hazy stratum, which covers the whole sky; more rarely, and perhaps only by an optical deception, it is seen under the form of stratus. Cumuli are very uncommon. After several dull days the clouds generally accumulate, descend lower in the atmosphere, and rest on the mountain; as a few drops of rain fall in the valleys, the clouds disappear, and the highest peaks are seen to have received a slight sprinkling of snow, which is soon melted by the rays of the sun. It is only very rarely that the quantity of rain exceeds a few drops, or merits the appellation of a shower. The few occasions on which I have observed any fall of rain, at all deserving of being called by that name, have mostly been in early spring or in the latter part of autumn.
TEMPERATURE.
When the sky is clear, the sun, in all parts of Tibet, even at great elevations, but especially in the valleys at and below ten and eleven thousand feet, is extremely powerful. The shade temperature depends, of course, in a great measure on the elevation above the level of the sea, but also on the situation, exposure, and many other accidental circumstances. In the lower part of the Indus valley, at elevations of seven and eight thousand feet, it is said to be frequently very high36, the clear dry atmosphere allowing the full influence of the sun to be exerted on the bare, often black rocks. Even as far up as 11,000 feet, in narrow valleys, the heat is often great in the middle of the day, but the more open plains are generally very temperate in the shade, and the nights and mornings are always cool.
On the tops of the lower passes, and in the alpine valleys, the temperature of the nights and mornings is, in clear weather, very much depressed by radiation, so that the mornings, except when the sky is overcast, are intensely frosty, at elevations of 15,000 and 16,000 feet, or far below the level of perpetual snow. This is the case even in the month of August, which is the hottest of the year. The shade temperature at these high elevations rarely rises very high, even when the heat of the sun is oppressive, as it is moderated by the action of the violent winds which so generally prevail.
The periods of cloudy sky, which now and then alternate with the bright sunshine, which is the prevailing weather, are in the alpine regions extremely cold. The stratum of cloud, at first high in the atmosphere, gradually lowers itself, and the traveller is enveloped in a frozen mist, followed most commonly during the night by a fall of snow. The quantity of snow which falls is very small, seldom, so far as I have seen, more than an inch or two in depth, and it speedily disappears as soon as the clouds have been dissipated and the sky resumes its usual serenity.
WINDS.
The whole of Western Tibet is subject to extremely violent winds, the course and direction of which could only be satisfactorily studied by a resident. From the great depth of the valleys, the wind in general follows their course, blowing at one time up them, at other times down. In unsettled weather the direction is extremely variable, often changing repeatedly in the course of the day, but in clear settled weather the direction of the wind is, during the day at least, more frequently up the valleys than in the contrary direction. I have not observed any constancy in the course of the wind on the passes, on which it would be principally important to be acquainted with it, but it probably varies in direction according to the period of the day, so that a traveller, whose time does not permit him to delay to register the changes as they occur, is not likely to be able to discover any general law.
The Tibetan wind, in the ordinary state of the atmosphere, commences after the sun has nearly attained the meridian, the mornings being in general quite calm. It increases in violence during the afternoon, sometimes till after sunset, ceasing to blow after dark, or at all events before midnight. This wind seems to be pretty constant over the whole country, from the upper Sutlej as far west as Rondu; and as a very similar wind blows in the valleys of Affghanistan, which have an identical summer climate in respect of moisture, it must, I presume, be caused by the influence of the sun, in heating the barren rocky plains and hills.
During periods of cloud, and throughout the winter, the wind is much less regular in its direction, as well as in the periods during which it blows. It frequently changes its direction very abruptly. About the equinoxes, or at the commencement and end of winter, at which times there seems to be generally a good deal of unsettled weather, it blows for some days with extreme violence. In March, 1848, at Iskardo, for several nights the wind almost amounted to a hurricane; its direction was from the south, or directly across the mountains. This was very commonly the case at Iskardo, in unsettled weather, during the winter, but never when the days were bright and cloudless.
SNOW-FALL.
The amount of snow-fall varies much, diminishing as we advance into the interior of the country, but being always much greater on the mountains than in the valleys at their feet. In the outer Himalaya, the amount at equal distances from the plains diminishes as we advance westward, but in the Kouenlun, where the source of moisture lies to the westward, the snow-fall diminishes rapidly from west to east. The same is the case in the valley of the Indus, where the amount of winter’s snow, except in the most westerly parts, is quite insignificant.
It is probably owing to the absence of cumular clouds, and to the general uniform expansion of the condensed vapours over the whole sky, that the outward manifestations of electricity—thunderstorms—are of very rare occurrence in Tibet. I find only one instance of a thunderstorm recorded as having been observed while I was in a Tibetan climate. This was at Le, in September, 1848, at which time there was a good deal of cloudy weather for several days. From the extreme dryness of the air, electricity is evolved with great facility by friction: all articles of woollen clothing, blankets, and even the hair, emit sparks when rubbed in the dark. I have even observed this to be the case at the elevation of 15,500 feet, in cloudy weather, when snow was falling.
GLACIERS.
In every part of the Himalaya, and of Western Tibet, wherever the mountains attain a sufficient elevation to be covered with perpetual snow, glaciers are to be found. The occurrence of glacial ice is a sufficient indication of the existence of snow of more than one year’s duration, and (setting aside trifling cases of masses of ice in deep and sunless ravines, which, indeed, are not an exception, as they have no motion,) it may be laid down as a general law, that every glacier has its origin in perpetual snow.
The converse of this proposition does not seem to be so universal. We have the high authority of Humboldt for the fact, that no glaciers occur in the Andes of tropical America, from the equator to 19° north latitude. Nor is it, I think, possible that the existence of glaciers should have escaped his notice, did they occur of such dimensions as would be indicated by the solitary and doubtful instance mentioned by M. Boussingault, to which Humboldt refers37, which is stated to have been seen at the same elevation as the town of Quito, or more than 5500 feet below the level of perpetual snow in that region of the Andes. The cause of the non-existence of masses of moving ice, in connection with the perpetual snow of the American tropics, must apparently be sought in the extreme uniformity of the seasons, and in the small quantity of snow which falls at any time of the year.
In every region of the earth, so far as is known to me, where the mean temperatures of summer and winter are very different, or where the climate is what is called excessive, perpetual snow produces glaciers. These rivers of ice, as they have most appropriately been called, vary very much in size and appearance. In the lofty chains of the cis- and trans-Sutlej Himalaya, and of the Kouenlun, whose peaks rise to a very great height, and collect in winter enormous depths of snow, they are of great length. In the central parts of Tibet, which are often lower, and even in their loftiest parts are less snowy than the bounding chains, the glaciers are of inferior dimensions, often of that kind which I have called incipient, where the snow-bed is at once cut off abruptly in an ice cliff, which can hardly be said to be in motion, or rather whose motion must be almost entirely from above downwards.
The general appearance of an Indian glacier seems in every respect to accord with those of Switzerland and of other parts of the temperate zone. It is only of late years, indeed, that they have been generally recognized in the Himalaya; but it must not be forgotten that it is only recently that the researches of modern investigators, and in particular the delightful work of Forbes, have familiarized the untravelled world with their appearance, and more especially with the fact and cause of their motion. It has also, singularly enough, long been the custom to look upon the Himalaya as a tropical range of mountains, in which it was, as a matter of course, regarded as impossible that glaciers could exist38.
The upper end or origin of a glacier seems commonly to be in an enormous snow-bed, occupying the whole space included by an amphitheatre of snowy peaks. The snow-slips and accumulations by which the snow-bed is added to during winter, must to a great extent remain concealed from human eyes; and in summer, when these icy fields are accessible, they are generally, I believe I may say always, covered by a thick layer of snow, which assists at the same time that it conceals the process by which the snow is converted into ice.
I have never measured the dimensions of any of the great glaciers of the Himalaya, nor is it easy to ascertain the length of any of them even approximately, as they are seldom traversed by roads, and are usually bent so that only a small part of their course can be seen. Many of them must considerably exceed ten miles in length; I have seen several which were more than half a mile broad; and the depth of the icy mass frequently amounts to hundreds of feet.
The appearance of the surface of a glacier seems to depend almost entirely on the inclination of its bed. Where the slope is gentle the surface is nearly uniformly smooth, or at most only slightly fissured. I have not had occasion to observe any fissures of more than a foot or two in width, so that, though often very deep, they are crossed without difficulty. In describing the icy surface as smooth, it is necessary to mention that such is only the case in the upper part of the glacier, where the moraines are small or only lateral. Whenever the surface supports rocky fragments in great quantity, it is extremely unequal till such time as the whole superficies becomes covered with stones, when the melting being uniform, the surface again becomes tolerably even.
On steeply inclined planes the glacier is traversed in every direction by enormous fissures, between which the surface is very irregular, rising into sharp icy pinnacles of the most fantastic shape and appearance. More than once I have seen extremely steeply sloping glaciers, which were terminated abruptly by a lofty precipice, at the bottom of which huge piles of boulders and occasional icy fragments sufficiently indicated the forward motion of the ice; at other times, the slope of the valley in which the glacier lies again becoming gentle, the ice ceases to be fissured and rugged, and is capable of being walked on without difficulty.
Moraines, which, on the larger glaciers and among mountains of easily decaying rocks, are of astonishing dimensions, form the margins of each glacier, and also occur longitudinally on different parts of their surface, increasing in number as the glacier advances, till at last the different series whose origin can long be traced to the different ramifications of the glacier, become blended into one. The nature, origin, and aspect of the moraines, the mode of melting of the ice beneath them, and the isolated pinnacles of ice which support large solitary boulders, agree so entirely with descriptions of glaciers in other parts of the world, that it is unnecessary to dwell upon them. The large glaciers are often a good deal lower in their central parts than where they are covered by a bulky moraine; and a curious ravine-like hollow, between the moraine and the bare ice, which makes the former appear as if entirely disconnected from the glacier, is of very common occurrence. There is, however, also very often an ancient moraine, not now resting on ice, which runs parallel to the glacier, and seems to indicate its former greater extent.
FORMER GREATER EXTENSION OF GLACIERS.
In every part of the Tibetan mountains, and in very many parts of the Indian Himalaya, I have thought that I could recognize unmistakeable proofs of all the valleys having been formerly occupied by glaciers at much lower levels than at present. At first sight it seems rather improbable, that in sub-tropical latitudes the present extension of perpetual snow should at any former period have been exceeded; but it would not be difficult to show that the mean temperature, and particularly the mean summer temperature, is very much higher in the Western Himalaya and Tibet than it might fairly be expected to be in such a latitude. In fact, in the more humid climate of Eastern Bengal, though at least four degrees nearer to the equator, the mean summer temperature at equal elevations in the mountains is probably considerably lower than in the mountains of North-west India, and the snow-level is certainly lower. It is fair, therefore, to conclude, looking back to a period when the sea washed the base of the Himalaya in the upper part of the Punjab, that at that period a very different state of atmospheric circumstances prevailed from that which we find at the present time.
Wherever I have seen glaciers in Tibet or the mountains of India, I have been able to trace their moraines to a level very considerably lower than their present termination; and when I find in those ranges of the Himalaya which do not at present attain a sufficient elevation to be covered with perpetual snow, series of angular blocks, evidently transported, because different from the rocks which occur in situ, and, so far as I can judge, exactly analogous in position to the moraines of present glaciers, I feel myself warranted in concluding that they are of glacial origin, and find it necessary to look about for causes which should render it probable that the snow-level should have formerly been lower than it is at present. In the rainy districts of the Himalaya, where forest covers the slopes of the hills, it is difficult to fix the lowest limits at which evident moraines occur, but in many places I have seen them at least three thousand feet lower than the terminations of the present glaciers. In the valley of the Indus, accumulations of boulders, which I believe to be moraines, occur in Rondu as low as 6000 feet.
Glaciers, as is well known, terminate inferiorly at the point where the waste by melting in any given time begins to exceed in amount the mass of solid ice which is in the same space of time pushed forward by the vis à tergo. In the mountains of Tibet the elevation of this point is very different in different places. It seems to depend principally on the mass of the glacier, as large glaciers invariably descend much lower than those of smaller size; the inclination of the bed has perhaps also some influence in determining the matter.
In comparing the glaciers of the Tibetan Himalaya with those on the Indian face of the same mountains, it will be found that, cæteris paribus, glaciers descend much lower on the Indian side, or in a moist climate, than in the dry and arid Tibetan climate. It is indeed impossible to ascertain with certainty that any two glaciers are of equal size, but it appears to me sufficiently accurate to compare the main glaciers on the opposite sides of the same pass. In the Umasi pass, which is situated in the main chain of the trans-Sutlej Himalaya, all the circumstances seem favourable for comparison. On the south side of this pass the principal glacier terminates at about 11,500 feet, while on the north side a much more massive glacier comes to an end abruptly at 14,000 feet. The difference then, on opposite sides of the same pass, where the pass coincides with the line of transition of climate, amounts to 2500 feet.
That I am justified in ascribing the cause of this difference to the change of climate appears from the fact, that in the interior of Tibet, where no such change is observed in crossing even very lofty passes, there is frequently a glacier on the north declivity when none exists on the south. This is the case, for instance, on the Parang pass, and on the pass immediately north of Le. It may therefore be inferred, that when glaciers occur on both sides of a pass, that on the northern exposure will, unless there be a marked alteration of climate, invariably descend lower than that on the south side. I have not had an opportunity of seeing glaciers on both sides of any pass in the most external ranges of the Himalaya, but I have been informed that in the range south of the Chenab river, glaciers frequently occur on the north sides of the passes, while none exist towards the south. If this were to be found universally the case, it would be an additional proof that the lower descent of glaciers on the south or Indian side of the mountain chain is an exceptional occurrence.
GLACIERS OF KOUENLUN.
The glaciers of the southern slope of the Kouenlun appear, from the descriptions of travellers, to be on a still more gigantic scale than those of the Himalaya. Five mountain ranges of great height, separated from one another by rivers of great size, descend from the axis of that chain towards the Indus and Shayuk, and attain so great an elevation, that, with scarcely an exception, there is no passage from one of these lateral valleys to another. All these ranges rise far above the line of perpetual snow, and in their valleys enormous glaciers descend to a level which is gradually lower as we advance westward in the direction of the source of the rain- and snow-fall. The range east of the Shayuk has comparatively few and small glaciers, but to the west of that river the glaciers of Sassar terminate at about 15,000 feet. A little further west, a glacier, overhanging the valley of Nubra, terminates at 14,700 feet, and the great glacier of Nubra was found, by Captain Strachey, to terminate at 13,000 feet. In the range between Nubra and the Machulu again there are vast glaciers, but their height has not been determined, nor do we know precisely to what level those of the Shigar valley descend; though it is evident, from their proximity to the main valley, and their small distance from Shigar, which is not more than 7200 feet above the level of the sea, that they must descend very low, perhaps to 10,000 feet. In the valley of Gilgit, I am informed by Mr. Winterbottom, the glaciers descend as low as 8000 feet.
LEVEL OF PERPETUAL SNOW.
In the mountains further east than the Shayuk it would appear that the snow-fall is so very small that the level of perpetual snow recedes to an enormous height. This has been found to be the case on the passes north of the Pangong lake, many of which were crossed by Captain H. Strachey. The great height of the mountains without snow, east of the Karakoram pass, confirms the fact; and it is probable, so rapidly does the snow-level rise in advancing eastward, that if we could penetrate a very short distance beyond the eastern extremity of the Pangong lake, an absolutely dry country might be reached, in which rain or snow never falls.
So much error has unfortunately taken place regarding the height above which the mountains of North-west India are covered with perpetual snow, that it appears necessary that travellers should put upon record the results of their observations, however limited. It is for this reason, and not because I expect to throw much additional light on the subject, that the following remarks are hazarded. The recent paper of Captain R. Strachey39 has furnished facts which had hitherto been wanting, while the theoretical considerations which have been laid down by Humboldt are so accurate and comprehensive, that the undoubted mistake into which he has fallen is the more to be regretted.
The Indian and Tibetan Himalaya, west of Nipal, lies entirely within the temperate zone, and from that circumstance has its year divided into summer and winter. The periodical rains, which it is well known are principally confined to the outermost parts of the mountains, being derived from the Bay of Bengal, are excessive in the easternmost part of the chain, and gradually diminish as we advance westward; there is no reason, however, to believe that the winter monsoon, which is particularly dwelt upon by Captain Strachey in the valuable paper to which I have had occasion to refer, is so. Probably indeed it is the reverse, though I have no detailed observations to refer to in corroboration of this opinion; I may however recall to mind, that the winter is the season of heavy snow, and the spring of heavy rain, throughout the north of Affghanistan, and that in the Punjab frequent cloudy weather and rain occurs during the cold season, while in the plains of India the weather seems to become at that period less unsettled as we advance eastward.
The quantity of rain which falls during the summer in the outer Himalaya has necessarily a very material influence on the sun’s action during the time in which he has most power, and therefore on the mean temperature of the summer months, which at corresponding elevations, notwithstanding the northing of the chain as we advance from east to west, must be higher to the westward. In the interior or Tibetan portion of the Himalaya, this difference is not observed, the climate being the same, or nearly so, from east to west of the region under consideration.
WINTER, THE SEASON OF SNOW.
In the most western part of the Himalaya, in Kashmir and Balti, the winter’s fall of snow commences about the beginning of December, and continues on the highest ranges nearly to the beginning of May. The supply of moisture from which the snow is condensed is evidently derived from the Indian seas, and I suppose principally from the south-west, that being the general direction from which I observed snow-storms to arrive at Iskardo. The fall of snow must therefore, equally with that of rain in the rainy season, be greatest in the outermost (snowy) ranges, and very much less in all those in the interior. In the lower parts of Tibet on the Indus the snow-fall during winter is very considerable, though during summer the climate is as dry as elsewhere in Tibet. This difference seems to be explained by the westerly point from which the winter’s wind blows, and by the much greater moisture of the atmosphere at that season over Affghanistan and Sind, so that the south-west wind advances loaded with vapour up the valley of the Indus. The increase of elevation in the bed of that river of course causes all the excess of moisture to be deposited without penetrating to any great distance, so that the more eastern parts of the country are not affected by this cause.
The snowy season in the highest mountains is probably in every part of the range very much the same. On the low outer ranges, which do not attain the height of perpetual snow, it is gradually lessened in duration as the elevation diminishes, ceasing entirely, in average years, at about 4000 feet. When the winter is at an end, the influence of a powerful sun and gradually increasing temperature is at once brought to bear on the mass of snow which has fallen; on the inner ranges where the summer is dry, this action proceeds uninterruptedly till the commencement of the next winter, but on the outermost snowy ranges it is modified by the access of the rainy season.
MELTING OF SNOW IN SUMMER.
On the outer ranges of the Himalaya, the crests of which rise to between five and ten thousand feet, the powerful sun soon dissipates all snow. It is in the inner ranges, which rise nearly to the height of perpetual snow, and where the river-beds are from six to eight thousand feet above the level of the sea, that the snow remains for a great length of time. When the valleys are open, the plain on the banks of the stream becomes first of all bare of snow, then the banks which face the south, and lastly the northern slopes. It is not so, however, in the deep narrow valleys and ravines through which the Himalayan rivers generally flow. In these the bottom of the glen is so much sheltered from the sun that a dense mass of snow, the result of accumulation from the avalanches of the winter, remains for a very long time after both slopes are quite bare of snow. These snow-beds have nothing of the nature of a glacier in them, but are simply firm, hard snow. I have, in the month of June, descended along one of them from 13,000 feet (above which height there was perhaps a glacier beneath), to 8500 feet, a distance of seven miles without a break. It was entirely confined to the bottom of the ravine, both banks being throughout all that distance free of snow, and often covered with a most luxuriant herbage.
SNOW-BEDS IN RAVINES.
Similar snow-beds are to be seen in every ravine which is not too wide to be choked up by snow in winter. Their occurrence so universally is probably in a great measure the reason why glaciers were not recognized in our Indian mountains till so recent a period. These beds being so clearly transitory in existence, it was assumed that all masses of snow and ice were equally so. A visit to one of the great glaciers at the end of autumn would of course at once have indicated the dissimilarity.
In many narrow ravines remains of these snow-beds may be seen at surprisingly low elevations throughout the year, their permanence depending much more on the amount of the winter’s fall of snow, and of the accumulation in that particular locality, than upon the mean or summer temperature of the place. At Baltal, in the upper part of the Sind valley in Kashmir, the little stream which descends from the Zoji pass was still arched over by a bed of snow several feet thick, in the end of September, at an elevation of not more than 9500 feet. This was not, as might have been expected, in a very shady spot, but fully exposed to the action of the sun; it was, however, in a place where the fall of snow during winter is very great.
The causes which are enumerated by Baron Humboldt as affecting the snow-level are numerous, but several are of only local effect. Two in addition to the latitude seem more important than the others, namely, the amount of fall during winter, and the amount of solar heat during summer. Captain R. Strachey regards the diminished amount of the winter’s fall of snow as the main cause of the greater height of the snow-line in the interior of the Himalaya, but I feel disposed to believe that both causes co-operate equally to produce the effect.
LEVEL OF PERPETUAL SNOW.
Captain R. Strachey has estimated (from the mean of several observations) the snow-level on the southern slope of the cis-Sutlej Himalaya at 15,500 feet. This elevation is, no doubt, as near as possible correct. Captain Herbert, in his geological report, had fixed upon 15,000 feet, which is a little too low even in the district of Basehir, to which his estimate, I believe, refers. In the trans-Sutlej Himalaya, from the diminished amount of summer cloudy weather, the snow-level is probably a little higher, but we are not yet in possession of any accurate determinations of heights in that range in those parts which are in close contact with the plains of India. Two of its ramifications are extremely well adapted for determining the height of perpetual snow. First, the Chumba range, which, as has been pointed out to me by Major Cunningham, is barely snow-tipped throughout the year; and second, the Pir Panjal range south of Kashmir, the northern slopes of which have perpetual snow and glaciers, while on the south side the snow has entirely melted before the end of summer. The elevation of the Pir Panjal has not been determined with accuracy, the heights given by Baron Hügel and by Mr. Vigne being estimated from their measurement of the pass over which they crossed40.
SNOW-LEVEL IN TIBET.
In the interior of north-west Tibet every principal range attains the elevation of perpetual snow, but only a few peaks rise much above it. There is therefore no very great mass of snow during the summer months to lower the temperature of the air, and consequently circumstances are the most favourable possible for the elevation of the snow-line to an extreme degree; a dry, stony, desert, treeless country, violent winds, clear sky, and powerful sun, being all combined. In the most central part of the country, the Lanak pass, near Hanle, and the Sabu pass, near Le, both elevated as nearly as possible 18,000 feet, are without perpetual snow, but the Parang pass, between 18,400 and 18,600 feet, has a glacier on its north face, and therefore exceeds in elevation the snow-line. The snow-level in central Tibet must therefore be sought between these heights, but nearer that of the Parang pass, which has no perpetual snow towards the south: it is, therefore, certainly not below 18,000 feet.
In the Kouenlun, on the northern border of Tibet, where the mountains are again much more elevated, the snow-level descends no lower. Even on the 19th and 20th of August, the mass of snow, which was on the northern face of its highest peaks continuous down from 20,000 feet and upwards, did not descend below 17,500 feet, and the open level plain of the upper Shayuk had at that height only trifling patches of snow. On the Karakoram pass (18,200 feet) there were only large patches of snow, the south face of the ridge being quite bare for some distance in both directions.
LEVEL ON OPPOSITE SIDES OF PASSES.
The vexata quæstio of the difference of the level at which snow lies on the north and south slopes of the Himalaya, affords a singular instance of misconception. Enunciated originally in an obscure and somewhat incorrect form, when little was known of the structure of the inner part of the chain, the fact has been repeatedly contradicted by those who thought they found it contrary to their experience. Both parties were to a certain extent right. On each individual range the snow-level will at all times be found lower on the north face than on the south, except when the range which we are crossing happens to coincide with a very marked and abrupt change of climate, which will only be the case when it is extremely elevated. When this is the case, the proposition, otherwise true of the mountains en masse, or the inner ranges compared with the outer, becomes applicable to a particular range. This is probably the case in the very pass in Kamaon (I know not which it was) from which the law was first inferred. It is certainly so in the great passes north of the Chenab, where, on the Indian face, I found in June snow at 11,500 feet, while on the north side, only twenty miles distant, it had already receded beyond 15,000 feet.
From the rapid nature of my journey, and the great number of objects to which I was obliged to devote my attention, the geological observations which I was enabled to make were much more imperfect than I could have wished. It appeared, however, desirable, hurried as they were, to enumerate them, for the purpose of drawing the attention of future travellers to the subject; and for the same reason I shall here recapitulate the general conclusions which appear to result from the facts observed.
GEOLOGY OF TIBET.
The greater part of Tibet consists of plutonic and metamorphic rocks; and from the gigantic scale on which the sections are exposed, and the general bareness of the mountains, which enables their structure to be seen, that country probably presents the finest field in which these classes of rocks could be studied. Granite occurs in great abundance, sending immense veins in all directions into the metamorphic rocks, which are seen to be everywhere upheaved and dislocated by the injected mass. In the immediate vicinity of the plutonic masses, all traces of the direction of the strata of the superposed rocks are lost; but elsewhere, with every variety of dip, it is very generally found that the stratified rocks strike in a direction which varies between north-west and south-east, and north-north-west and south-south-east. As all my observations were made roughly and unconnectedly, and without my discovering this identity till after my return to India, the strike is probably very uniform throughout a great extent of country.
It is not a little remarkable that a belt twenty miles wide, in the direction of this line of strike, drawn from Iskardo to the Niti pass, would cover every place south of the Indus in which limestone has been observed in Tibet. It would pass through Molbil on the Pashkyum river, the limestone districts of Zanskar, and the Lachalang pass, where limestone was found by Gerard. It would also cover Piti, Hangarang, and Bekhar, all well-known limestone tracts. Of course the limestones of Nubra and the Karakoram on the one hand, and of Kashmir on the other, cannot in any way be connected with this line.
The sandstones, slates, and conglomerates, which so closely resemble in appearance those rocks which in Europe are chiefly members of the old red sandstone and greywacke series, appear to assume also the same direction. I bring forward these coincidences of direction only as a remarkable fact, worthy of investigation, without attaching any great weight to them, as more careful observation may show that they are merely accidental, and that rocks of very different ages exist among the limestones and associated rocks of the northern Himalaya.
ALLUVIAL AND LACUSTRINE DEPOSIT.
The great extent and development of a very modern alluvium-like formation, composed of great masses of clay with boulders, and occasionally of very fine laminated clay, constitutes one of the most remarkable and striking features of Western Tibet. In every part through which I have travelled, and at all elevations, except on the highest passes, I have found these deposits in greater or less quantity. In their most common state they consist of loose earthy or clayey unstratified masses, containing boulders either angular or rounded. Very fine clay, distinctly and horizontally stratified, is also common; sandstone and hardened conglomerate are more rare, but also occur occasionally.
That some of these beds are of lacustrine origin, the occurrence of fresh-water shells appears to prove very clearly; and though here and there small portions may be terrestrial and of glacial origin, it cannot, I think, be doubted that the great mass of the boulder clay was deposited under water.
In the structure of Scotland at the present day we have a state of circumstances which appears to me capable of throwing much light on the nature of these deposits. We find there a series of narrow arms of the sea, stretching far into the land, and separated by rugged and generally steep ranges of metamorphic or plutonic rocks. They are all more or less silted up by sedimentary matter, and near their mouths, especially where, as is often the case, they are much contracted, we generally find a bar, shallower than the remainder. At various elevations above the sea-level again there is a series of fresh-water lakes, differing little in aspect from the arms of the sea. We find also in many parts of the Highlands of Scotland long valleys, nearly level, which are filled with incoherent sedimentary deposits, and bounded like the lochs by steep mountains. If these were formerly arms of the sea, which by the elevation of the land have been converted into dry land, then the fresh-water lakes probably occupy those parts of the narrow channels which were originally deepest, or which, being wider than the rest, have remained unoccupied by sedimentary matter at the time of the elevation. In conformity with this view we find that at the lower end of these lakes the mountains generally approach very close to one another.
If we were to suppose the gradual elevation of Scotland to continue till the mountains attained an elevation equal to that of the Himalaya, it is evident that a continued series of marine sedimentary deposits would extend from the summit to the sea-level, unless removed by the action of streams or other ordinary causes. Some of the valleys would be of considerable width, and would contain marine fossils in great abundance; but in the narrower mountain valleys the gravel and boulders would be quite destitute of fossils. Here and there fresh-water formations of partial extent would occur, but they would be separated from one another by large tracts filled with marine beds. The gradual elevation of the land would bring to bear upon these incoherent strata the powerful action of running water, which would remove portion after portion, till at last deep valleys would be excavated, and small patches only of the gravel and clay would remain where the action of the streams was least powerful. Such I conceive to be the present state of Tibet, but a much more detailed investigation of that remarkable country would be necessary, before this view can be regarded in any other light than an hypothesis.
The causes by which the metamorphic rocks, which must have been brought into their present remarkable state at a great depth in the interior of the globe, acquired their present configuration of mountain and valley, form a question on which I am not now prepared to enter. One continued process of elevation seems inadequate to produce the observed effects; but however numerous the alternations of elevation and depression may have been, it is evident that the alluvial deposits at present existing must all be referable to the last period of elevation, as such incoherent strata could not withstand the continued action of the sea.
Footnotes
1Voyage, etc., vol. ii. p. 6.
2In this I allow 800 feet for the height of Loodiana above the level of the sea.
3Journal of Agr. Hort. Soc. Calc. vol. iv.
4Gerard’s ‘Koonawur,’ Appendix, Table 3.
5I have carefully compared, since my return to England, a great many specimens of the Himalayan Picea, and am sorry to be obliged to dissent from the opinion of their distinctness, which has been expressed by many excellent observers. Great variations occur in length of leaf, which is either green on both sides, or very glaucous below. All have notched leaves, but the notch varies much in depth and form. There are also differences in the form of the cones and the shape of the scales. The long green-leaved state is that of the moist Himalaya; in the driest regions the very short glaucous-leaved form occurs. There are, however, among the specimens collected by Wallich, Strachey, and myself, so many intermediate forms of leaf, that I feel satisfied that all must be considered states of one species, varying, like most Coniferæ, with climate and other accidental circumstances.
6I have now no doubt that the whole of this descent was over an ancient glacier moraine, but I was not at the time familiar with glaciers or their moraines by personal experience; and though on this and other similar occasions my notes show that I was much puzzled by the numerous transported blocks, the idea of this explanation did not suggest itself to me till I had an opportunity of seeing the connection of such phenomena with actual moraines.
7The distant snowy mountains seen from the top of the Hangarang pass are probably those due north of Zungsam and east of the Parang pass, which Major Cunningham, from some angles obtained on our journey, estimated (I believe, but quote from memory) at nearly 24,000 feet.
8La, in Western Tibet, seems to mean always a pass. To the eastward it is often translated mountain.
9Jacquemont writes this name Khiri. I follow the orthography which I find in my notes made at the time.
10This limestone will, I believe, turn out to be the counterpart of the limestones of Silurian age, which form one of the most interesting results of the labours of Captain R. Strachey, in Kumaon and Garhwal.
11A very excellent sketch of the fort and village of Dankar, by Mr. Trebeck, is given in Moorcroft’s Travels, in which the appearance and position of the alluvial masses is well represented.
12I state these facts on the authority of Major Cunningham. Captain H. Strachey visited this district in 1848, and will, I hope, soon make public his observations. He has ascertained that the surface of the lake is 15,200 feet above the level of the sea.
13Turner’s Tibet, p. 406.
14Phil. Tr. 1787, p. 297.
15I have made over all my specimens of the borax and other saline products of Tibet to Dr. R. D. Thomson, of Glasgow, who is at present engaged in examining them.
16This juniper has a very extended range in altitude, being common in the drier parts of the Himalaya at elevations of 12-13,000 feet, and in some parts of Tibet, where it meets with a higher summer temperature, even as high as 14-15,000 feet. It is the Juniperus excelsa of Wallich, and, so far as the point can be decided by dried specimens, seems identical with specimens in the Hookerian Herbarium, collected in Karabagh and Sakitschiwan by Szowitz, and communicated to Sir W. J. Hooker by Fischer. The Taurian specimens of J. excelsa from Bieberstein are, however, a good deal different, and are perhaps only a form of J. Sabina.
17In Moorcroft’s time, this place was a small village.
18I have been told by Dr. Jameson that he has met with it in the Kangra hills, but that he has never seen it in Mandi.
19A species of vine was very common in the forests, climbing to a great height on the trees, which very closely resembled the common cultivated vine, from which it is not, I think, specifically distinct. At the same time, my specimens are scarcely distinguishable from Vitis Indica, L., a species of the plains of India, not uncommon in hot jungles, even at a considerable distance from the foot of the mountains.
20Travels, vol. ii. p. 11.
21Written, I believe, Snurla, as Le is written Sle, and Nimo, Snimo, the initial letter being in all three mute. Many similar instances might be given, silent initial letters occurring very commonly in the written language of Tibet. It admits of much doubt whether the best mode of spelling be according to the pronunciation, or as the words are written: I have preferred the former, as less likely to mislead.
22I do not know whether or not to attribute to this plant a remarkable disease which, on my return down the Indus in September, I found in the village of Saspola. At least thirty people in that village, of all ages from a full-grown man to an infant, and of both sexes indifferently, had been attacked with paralysis within the last two years. The palsy was confined to the lower extremities, and differed much in degree. The sufferers were in other respects the most healthy and good-looking portion of the inhabitants. The people themselves were quite at a loss to assign a cause for this extraordinary affection, and, except in some article of diet, I was unable to think of any.
23This view has been suggested to me by Dr. R. D. Thomson, who has paid much attention to the chemical contents of springs, and is at present engaged in examining the saline matters which I brought with me from Tibet.
24Two months later, Captain Strachey ascended the Nubra valley till stopped by this glacier, which appears to be on a still more gigantic scale than those of the Shayuk to the eastward.
25Excellent specimens of this singular alpine plant, each tuft of which must, I think, represent the growth of centuries, may be seen in the Museum of the Royal Gardens at Kew, collected by Dr. Hooker in Eastern Tibet.
26I have no conjecture to offer regarding the age or nature of this very remarkable rock.
27The itinerary of Mir Izzet Ullah shows that at the time of his journey from Le to Yarkand the direct road up the Shayuk was still open.
28Asie Centrale, vol. i. p. 14.
29Manasarawar and Rawan Rhad.
30Moorcroft’s Travels, vol. ii. pp. 47-50.
31Journal of the Asiatic Society of Calcutta, 1842, No. 126. Captain Herbert, who had travelled a great deal in the Himalaya, was the first to point out the impropriety of regarding these mountains as a single chain parallel to the plains of India. Jacquemont also arrived at the same conclusion, as will be seen from the following extract from his journal:—“Le langage de la géographie descriptive est théorique; c’est une grande faute si les théories qu’il rappelle sans cesse sont dénuées de fondement. Ainsi l’on dit que le Setludje coupe la chaîne centrale de l’Himalaya, que sa vallée est creusée au travers, etc., etc., et l’on donne à penser par là que cette chaîne auparavant etait continue et que c’est par un effort des eaux que s’y est faite cette large trouée, comme si les montagnes avaient dû se former primitivement avec une continuité non interrompue” (vol. ii. p. 201); and again (at p. 269), “Le Setludje coule donc non au nord de l’Himalaya, mais entre deux chaînes à peu près également élevées.”
32Captain R. Strachey, in his paper on the snow-level, proposes to call the more western part of the Cis-Sutlej Himalaya the Busehir range, a name which, though exceedingly appropriate to the portion to which he applies it, is not adapted for extension to the more eastern part.
33Travels in Kashmir, etc., vol. ii. p. 382.
34Travels, vol. i. p. 361.
35That Tibet is not an extensive plain, according to the usual idea, has already been pointed out by Humboldt (Asie Centrale, vol. i. p. 12). Chinese geographers, according to him, describe all parts of Tibet as more or less mountainous; the eastern portion of West Tibet (Gnari) as least so. Captain H. Strachey, in his account of his visit to lake Manasarawar, says expressly that “the surface of Gnari is for the most part extremely mountainous.” In the lower Tibetan course of the Sutlej, the recent discoveries of Captain Strachey show that an alluvial table-land of considerable extent exists, intersected by deep ravines.
36See some observations of the thermometer recorded by Mr. Vigne, at Iskardo, Khapalu, etc.
37Asie Centrale, vol. iii. p. 22.
38In the Map No. 65 of the Survey of the Western Himalaya, by Captains Hodgson and Herbert, the glacier of Gangutri is marked “Great snow-bed or glacier;” but whether this indication of a knowledge of the true nature of the mass is due to the surveyors or to the maker of the map in England, I have no means at present of ascertaining.
39On the Snow-level in the Himalaya, in the Journal of the Asiatic Society of Calcutta.
40The thermometric results obtained by these two travellers do not agree with one another. M. Hügel’s thermometer indicated 6300 feet for the elevation of Kashmir, a result which is known from the barometric observations of Jacquemont to be 1000 feet in excess. Mr. Vigne’s thermometer, when tested by Moorcroft’s barometric results at Le, errs considerably in the opposite direction. In neither case do I know the mode of calculation employed, the results only being given.