Things Seen
To discover whether a distant slope is snow or ice, if the character of the surface is not apparent at once, or deducible from its position, aspect or angle, we must wait for sun or strong daylight.
Snow Surface Condition.
Ice surfaces—that is, the smooth ice surfaces found in the Alps—reflect light as an even, steely glimmer, like elongated pools of water. Black ice, not so often found in the Alps, has a different quality in reflection. Granular ice is distinguishable by its reflection of light in facets or prisms. It will be noted that these tend to increase in size as our inspection descends the length of a glacial slope. The honeycombed ice found in tropical ranges is quite distinct in character; it can be recognized from a distance, and in a photograph, by its surface forms.
Snow surfaces show plain white or grey in comparison.
An ice crust upon snow has an appearance much like that of ice, but the reflected light is ‘pockled’ and uneven.
New snow, which is best left alone, has a brilliant fresh surface. Seen even from great distances, and especially upon rock, it shows a filmy, gossamer, veil-like quality. This endures until the aeration has escaped and the feathery surfaces have subsided into harder contours.
Old powdery snow, as contrasted with new snow, has a greyer tint when seen from a distance, particularly if not seen in direct sunlight.
Old wet snow, laborious to cross, and deciduous according to its angle, shows a bluish, luminous surface light, especially in its depressions. It is often transected by visible lines of strain or cleavage.
A thawing snow surface, seen from near, is dull and drenched looking, or pitted with small holes.
Surface hard-crusts, or plates, produced alike by wind and sun, which afford pleasant going but possess the avalanche potentiality if the angle is steep and their attachment to the surface below is slight, generally mark themselves off from the surrounding snow slopes by a lower, duller tone; sometimes they are tinged with a yellow shade. The plates vary in thickness, deepening towards the middle, and they can often be recognized by their edges, which run out on the neighbouring snow in darker wavelets, sometimes with eyebrow-markings round their curves.
Old hard snow, of deep attachment and sound progress, lies in alternating wave and hollow of different tones of light and shade, where the sun has been at work on the surface. It is often dust-speckled, or shows bluish finger-prints.
Granulated snow, in strong light, may show bright or prismatic reflections from its facets, similar to, but easily distinguishable from, granular ice prisms.
As confirmation, or correction, of what distant observation may have revealed about the character of ice or snow surfaces, general considerations must also be taken into account: the recency of the snowfall, the subsequent weather, etc. There is also the final test of touch, which is made on the spot, before any snow slope is traversed. The change in the condition of the snow, which may be produced by a day of sun before we can return down the slope, must not be left out of the calculation. Many slopes whose surface may be adjudged and found safe for passage in the early morning cannot be trusted by nightfall.
Angle on Snow.
It is essential to be able to judge of the inclination of a slope; for some harmless conditions may become dangerous if the snow is lying at above a certain angle. New snow, for instance, has been known to slide at as low an angle as twenty degrees. Hard old snow, melted and refrozen, may be supported in small patches, and remain reliable, at as high an angle as sixty degrees.
The power to estimate the angle of a slope by the eye only comes with practice. Most slopes look precipitous in face. But a mountaineer who has trained his eye by first going round to see a number of such slopes in profile, and by then returning to see them in face, has learned what he must deduct from an apparent angle. He is then qualified to make a truer estimate of the real angle of slopes which he may be able to examine in face alone.
Snow cannot lie at anything like the angle at which it often appears to lie when seen in face. From the presence of snow, in fact, much can be argued as to the generally mild angle of the mountain face on which it lies. Except in narrow couloirs, where it is supported by the walls, snow does not lie permanently above or even up to an angle of fifty degrees. Most big snow slopes are considerably less. The broader the face on which it lies, usually the less the real angle of the snow.
The fact that a big snow peak presents a continuous slope of snow to its summit is evidence that the mean angle of the ascent is not great, otherwise the even accumulation could not have proceeded. In prospecting a new mountain, therefore, however tempting its rock face or ridge may be to a modern climber, its snow side, if it has one, may be assumed to offer the inclination of easier ascent. And this more particularly if the snow slopes face towards the south, where the snow would naturally adhere least to the face.
Interruptions to climbing on such snow faces, whether as steeper slopes of snow or as ice walls (such as it is well to note beforehand), are at once apparent from their different shading if the snow slopes are inspected when the sun is overhead.
The inclination of a hanging slope of snow always appears still more exaggerated as seen from in front if it lies on the face of what is mainly a rock peak. We have in such case to discover if the snow is lying on ice, or only forms a coating to the rock. If it is on ice, the lower edge of the slopes, where the snow runs out on to the rock, will generally betray a rim or broken wall of ice. To judge of the quality of such a snow surface, and of the strength of its attachment to its ice or rock sub-surface, the slopes below it must be examined, and snow, stone or water furrows looked for. By the crumpled or the clean appearance of the edges of the slope itself, where it touches the rock walls on either side of its descending fan, much can be learned of its past transmutations and present condition.
Long or short spits of lighter snow, running up against darker snow or ice, are the retentions of later falls, and are indications of uneven angles of surface. They betray the presence of bulges or ribs below, and, besides their promise of easier progress on slopes where the general surface may be frozen hard or over-steep, they give us by their contrast a further basis for our estimate of the actual inclination.
The presence, the shape, and the number of cleavages or crevasses in a slope of ice or snow are a further guide to our estimate. A certain type of crevasse is only found on slopes lying at an angle of about forty-five degrees.
We may get additional evidence, in cases of doubt, by waiting for the sun to throw the shadow of another peak or shoulder upon the slope. When the sun and the interruption are located, the distortion of the reflection will allow of an approximate estimate of the angle of the snow slope.
Faces or ridges of mingled rock and snow, and surfaces interrupted by the intrusion of any detail, be it only of a shadow or tint, are always easier for the experienced eye to estimate, in angle and character. Where we have rock and snow or light and shadow in contrast, practice in the reading of snow and ice surfaces, and in the rules that govern their angles of inclination and attachment, and practice in the interpretation of the details of rock structure, become mutually and comfortably corrective.
Snow Cornices.
Cornices form against the wind, not with it. The contrary is sometimes stated; but the error is possibly due to the fact that irregularities in the configuration of a ridge often produce back eddies in a cross-wind. If the prevailing wind is snow-bearing, and across, a snow-bearing back swirl may build a small cornice on the sheltered side of a ridge. Such a small cornice would appear to have been formed with the prevailing wind: actually it would have grown against its return eddy. A wind blowing along (not across) a serrated ridge may similarly produce very small cornices facing either way on the ridge, and apparently at right angles to the prevailing current, owing to some tower or curve on one side or the other having created an inward and upward cross-eddy, and a shelter from the main-current in which the snow-laden eddy can work. Large cornices facing either way on the same ridge, and the double cornices, are produced by a shift in a snow-bearing cross-wind to the directly opposite quarter. If we find ourselves on a corniced ridge when a strong wind, and especially a strong wind from a warm quarter or with Föhn in it, is blowing against the back of big cornices, i.e. from the opposite direction to that from which the snow-bearing wind was blowing which formed the cornices, we have to be even more careful, if that be possible, in dealing with them, as such a wind will loosen their attachment and magnify the suddenness and the size of their collapse. A cornice will always form more easily on the summit of a sheer or abrupt wall, which creates a strong upward eddy in a wind blowing against it, than upon a more gradual or snow-rounded inclination which offers less resistance to the current and less ‘catch’ to its snow burden. For this reason, upon a summit or a ridge which has, as so often is the case, one more gradual snow side and one rock side inevitably steeper, we must be prepared to find cornices overhanging the rock face, larger if produced by a wind-shift, lesser if by a back eddy, even though the prevailing wind has blown regularly upon the opposite snowy face, and should have relieved us of the necessity of caution by its failure to develop cornices on that side.
In general, therefore, the direction of the prevailing wind can give us no certain guidance as to whether or not to expect the existence of cornices. If a snow-bearing wind has blown against the visible side of our ridge or summit, we shall see them. If upon the invisible side, we must assume their presence until we can disprove it. But a wind-shift or variable current may always contradict our calculations. A cornice is very quickly built.
If we have not been following the performances of the prevailing wind, or if we mistrust its portent in any case, we have to rely upon visual evidences when we are prospecting the approach to any snow summit or the traverse of any snow-crowned ridge. In the case of a single summit it is less trouble to assume the presence of a cornice, until we fail to find it. In the case of a continuous ridge it may save us much tribulation to ascertain its condition in this respect before we start out for a long day upon it. If there are cornices, and they project towards us, they will at once be recognizable; if away, it is not always easy to make certain, without getting a sight of some part of the ridge in profile. Their detection at one point of a ridge will dictate the necessity of precaution along the rest. A telescopic examination can often discover the thin dark line of junction or strain, running parallel to the crest in the snow on the near side, where the projection of a cornice towards the far side starts its inclination. (In more considerable snow ranges, such as the Andes, this crack has, I am told, on occasion been proved to be due to a longitudinal crevasse on the ridge. In the Alps, however, I know of no case of this having been observed.)
An alternative and rarer indication will be the discovery of a band of shadow or duller tint, seen in the right light, running along the snow wall just below some part of the crest. This will be due to a relative steepening of the snow wall, sometimes even taking the form of a concavity, where the back of a high, steep cornice, facing towards the far side, hummocks up off its supporting ridge. The appearance I believe to be occasioned by a fall or a shift in the prevailing wind,—a fall permitting the snow to accumulate upon the head of the cornice and form a sort of bulbous whale-back over it, or a shift of wind to the near side beginning a projection which may ultimately grow into a ‘double’ cornice, with the higher of the two facing towards us.
Failing either of these signs, any two projecting points of rock or snow, near together on the suspected ridge, should be examined. If the connecting line of snow between them shows sharp and continuous against the sky, and ascends at its either end in a continuous single curve to the points selected, the cornice on the far side, if any, will be slight and local. If, however, the snow rim seems to merge indefinitely on the skyline, and its curve ascends to the points at either end in a variable arc of different centres, so that we seem to see, as it were, round the edge of a fold where the snow-curve hangs to the rock points, a cornice is indicated. If the breadth of the points or towers is sufficiently ascertainable to enable us to estimate the average thickness of the connecting rock ridge hidden below the snow between them (as it usually is unless the towers are seen absolutely flat in face), then the look, almost a reflection, in the sky immediately above the snow curve, and the character of the snow curve where it wavers over against the sky, will indicate to an expert eye whether the cornice is large or small.
Where, again, sufficient rock points projecting from a snow ridge are visible, as we see it in face, to suggest what must be the actual line of the snow-covered rock connecting them, any wayward sweep away from us in the visible line of the snow between them is an indication that the snow rim, where the skyline thus unaccountably retreats from the eye, is superintending a cornice on the far side.
The presence of a double cornice—the fatal cornices that face two ways, one built up above the other—is not difficult to establish. A band of shadow or low light on the near side of a snow crest, below a band of higher light, means a lower cornice facing towards us under an upper cornice curving away. A band of markedly higher light, below a band of shadow or obvious concavity, means an upper cornice facing towards us above a lower cornice facing away.
For all such observations on snow, which find their opportunity in the relative positions of light and shadow, it is apparent that a time must be chosen when the sun shines from the right quarter. Their accuracy depends upon their being continued over a time sufficient for the sun to travel past, and so indicate to us dimension, by the change in, or the disappearance of, the shadows cast.
Wind and Snow Signs.
Wind is not ‘seen,’ but its immediate effects upon snow are, more especially on high ridges, corniced or otherwise. The quality and quantity of the surface snow on a ridge, which it is important to know beforehand, can be discovered in times of wind from the amount and direction of the snow particles, which are seen to be blowing off the ridge, and appear as a film or puff of vapour upon the sky just above. The absence of any halo to the ridge, in spite of the manifest action of wind upon adjacent clouds, is equally valuable evidence of the stable quality of the snow.
The direction and force of the wind will often suggest the side of the ridge to which we shall prefer to limit our passage on the morrow. On the windy side, if the ridge be snow-covered, according to the quarter and character of the wind, the snow will be crusted or hard, or we may have to encounter a bare sheet of ice. If it be rock, again according to the wind, we shall find the holds either cleared or ice glazed in the morning. On the side sheltered from the wind, on a high exposed ridge the snow should be just of good quality. But even on such ridges it may be spongy and cantankerous if the wind has had Föhn in it.
In a bad season, or after a storm of ‘dry’ snow, it is worth while examining high ridges that have been exposed to the wind, on the chance that they may not have been closed by snow for the usual three days, like other peaks. A friend and I owed our own last great climb to having observed that the Zmutt ridge of the Matterhorn had been blown black and bravely snow-clear by the same storm that sheeted all the other ridges and summits of Zermatt in white, untimely mourning.
Apart from the indirect evidences it brings, wind, keen or warm, gusty or continuous, has its direct bearing upon the comfort, the safety and even the possibility of our climbing. Of its effects on snow surface, on rock falls and upon morale I have written elsewhere.
Ice.
Ice sheets on snow peaks are located from a distance by their reflected light; but it is well to memorize or sketch their position and extent beforehand, especially if we expect to have to cross them upon our descent, since they will be usually invisible from above. If there is prospect of our glissading, the exact positions of interruptions, ice shields, bosses, etc., must be known in advance.
Ice upon rock is apparent, either as a grey-blue, bottle-glass bordering to the stippling and nestling of old snow, or in the refrozen festoons of new ice, exquisite and evil, that complete the Gothic character of granite pinnacles.
Lazy, main glaciers reveal themselves frankly. The solution of their complexity is the business of ice craft; but distant inspection is concerned to discover the easiest line of ascent or descent, if the glacier is to form part of the expedition.
The most difficult hanging glaciers—that is, those with the largest systems of crevasses—will be as a rule the most steeply inclined. They will be therefore the easiest to prospect, even in detail, as seen in face from far off. Very few hanging glaciers descend evenly or straight. Either side or the centre will be moving the faster, and receiving the fuller reinforcement. The line of the great crevasses will slant upward or across, from one side to the other, or from both sides to the centre. And along the edges where the lines of varying pace and pressure adjoin and descend in conflict will be found, if there are no abrupt ice falls due to uneven bedding, the least interrupted route. Contrary pressures often tend to squeeze up the ends of successive cross-lines of crevasses, creating a tortuous but consecutive eddy of passage. Though the crevasses may still exist, as walls, séracs, etc., they will be more compressed and negotiable on this line. Frequently the cleavages will here survive only as partial splits, and across and down the edges of the unsevered splinters or flakes a continuous descent will be possible. But climbers may skirt round the mazes of glacier causation, if they have but eyes for the visible surface clues. It is enough for them to note from afar and remember by marginal marks where the best line of traverse from side to side, or from side to centre, should be started, in order to keep or recover the mobile thoroughfare. On large glaciers this is often very difficult to rediscover once we are on the ice, when our view is restricted by its irregularities of surface.
Similarly, to enable us to get on or off any glacier, we should note beforehand the position of convenient side-bays, where the ice runs out on to the rock in smoother, spent waves.
Couloirs.
Even as the passage of couloirs might be considered as belonging to snow and ice craft or to rock craft, so also their consideration is transitional to rock reconnoitring.
On large mountains the important thing to know about a couloir beforehand, if we intend to use it, is whether it is filled with ice or with snow, and whether it is subject to stone fall.
To information on the first point, the study of the angle of the couloir is the first help. A steep angle generally implies that the lining will be ice and not snow.
But as snow, supported by retaining rock, may remain at a very high angle, we look to see if there are any furrows in the white surface. If there are furrows and they are in ice, they will show us ice reflections in sunlight. If there are no ice reflections and they are therefore in snow, or if they are only ice-backed and therefore in snow-covered ice, the depth of the furrows will tell us what depth of snow we may expect upon the ice. If there are no furrows, the edges of the supposed snow must be inspected for further information. Where the snow runs out on to the rock at the side in ice webs, the surface tone will appear of different qualities if it be snow on ice, or if it be ice throughout.
And after all our examination, we may be agreeably surprised to be able to ascend on hard snow in the early hours where we had calculated from the angle that we should be hacking in snow-ice; or as disagreeably disappointed to find snow of avalanche quality, on a late return or after warm wind, where we had located snow of the best bearing variety during a morning inspection.
The base of the couloir should be inspected for traces of previous snow avalanches, and for the character of its bergschrund. We see if we can whether the summit of the couloir is commanded by glacier or slope likely to use it for the discharge of snow or stones. If so, we note during what hours the presence of sun will increase the risk, and when shade to diminish it may be looked for.
In a big couloir we mark down islands of rock which, in case we are detained in the recesses until stone fall time, will provide us with screens below which to steer our line.
We study the lie of the strata and the containing walls for possible exits from the couloir. On big peaks the top of a couloir often opens upon an amphitheatre of slabs, too thinly ice coated for steps. It is then important to mark down a line for escape in time.
If the base of the couloir selected can be seen, the presence there of fallen stones is evidence that they have fallen; but their absence there is not conclusive that they have not. They may have been swallowed by the bergschrund, disappeared into some crevasse, or lodged in soft concealing snow. For this end we must examine the edges of the schrund and of any cleavages for traces, and the surface of the lower snow for pockling. If there are channels worn in the snow or ice at the base or back of the couloir, we shall get further evidence that something is accustomed to fall. These channels may have been made by stones, by ice trash or by water. In sunshine the difference is distinguishable. If the runnels are ‘silver-backed’ in sunlight, and there are no stones apparent, they have been made by water and are harmless.
If the couloir to be visited descends on to a visible glacier, but is itself invisible, the presence, absence or scarcity of fallen stones discoverable at the bottom end of the glacier, subject always to the possibility of the consumption by rift or crevasse, will demonstrate the couloir, or couloirs, commanding the visible glacier to be proportionately infected with, free from, or only in some cases liable to, the falling sickness.
Rock.
In prospecting rock routes we have more to help us; for rock, unlike snow, does not change its skin, and when it hides itself, under ice or snow or water or glaze, the change from the black Ethiopian is obvious and calculable. We have also preliminary information, if not in books yet in the outlines of the mountains themselves, as to what is the character of the particular rock before us. Every climber, if he can assume the presence of limestone or granite or dolomite, sandstone, trap, chalk, or a few other of the elementary and lay classifications, has a clear picture in his own mind of the kind of climbing and of rock holds that he may expect.
Faces.
The slopes of the hills will tell him in general; good glasses will tell him more of his particular route or of local modifications in the characteristics:—such as how the rock is weathering; in which direction the strata are dipping; and what is the fashion of the jointing. Putting this information and his knowledge of the type of rock together, he will know upon which side to attack his peak.
For instance, if the strata dip through the peak, the aspect of the mountain upon which the upper ends of the strata emerge will give him holds sloped upwards to his advantage. This side, with its retroussé ledges, will also hold fresh snow longest after a fall, and at such a time afford him a further chance of locating the lie of traverse and shelf. If the main cleavages, again, are vertical, he will select the most weathered face, where the jointing will give him platform and shelf. If they are in the main horizontal, he has to seek the side that presents the most sequent line of weathering rifts or fractures, in order to connect up the natural horizontal ledges.
Just as a sunny day is of most help in prospecting an unknown snow climb, so is the day after a snowfall invaluable for the examination of rock routes. I owe several fine new rock climbs to snowfalls. Not only does the lodging snow indicate particular ledges and their intervals in detail, but it discovers to the eye general connecting lines of traverse or slope, which may be too interrupted or too foreshortened to be perceptible upon a distant inspection of the bare and broken rock face. Under snow the main lines of rock structure leap into sight.
By a convenient law of rock formation, the little apes the great. Thus, if we can discover the general inclination of traverses across a face, however large in scale, broken or interrupted their lines may be, it is safe to assume that the small details which make up these lines, the ledges, etc., will be reproducing the same fashion of structure in little. Where there are big terraces, there will be small ledges copying their form and direction. If there are big visible gaps, giant slabs, or terraces interrupted and continuing at a higher level as a result of uneven upheaval, in the same or similar places, although too small to be visible, the climber has to look out for exposed passages on slabs, or he will have to search for cracks to connect up his interrupted ledges.
It is all but impossible to inspect a distant climb with sufficient minuteness to be absolutely certain that a fifteen-foot wall or a broken ledge may not stop all progress at some point. Very rarely we can say, “It is impossible;” occasionally we can say, “It will go for certain;” but generally we have to leave some portion to the ‘round the corner’ chance. In such case we can reason with advantage from the big to the small, interpreting the main features of a face or ridge into terms of detail suitable for our lesser needs, and justifying it by our experience of similar rock.
Fortunately, rocks generally prove us right. They seldom cheat us, by a petty exception, of the fruits of general conclusions which we have based upon observation of their principal tendencies. On the contrary, we are constantly helped by kindly accidents and flaws, where we might expect no mercy. The Grépon traverse is a delightful instance of unreasonable progress just made possible by a series of, apparently, gorgeous accidents. The flukes are so brilliant and so timely that the layman cheerfully assumes them to be a rule in attacking similar Aiguilles; and he is rarely disappointed. When the expected and the unexpected alike fail us, on such rock we can still count upon a kindly roughness of surface and upon homely methods of friction to join up connections which structure and luck would have, for once, denied to us.
In reconnoitring all rock faces, especially for new routes, we are alert about the matter of falling stones. On boldly sculptured faces the edges of the ribs will be the safest line. On faces of shallow relief or much interrupted modelling, we may assume that nothing but the angle or our fortune will secure us against cross-fire. We used to be told that we should avoid stones by selecting aspects where the up-lie of strata emerged in sky-ward and stone-catching ledges. But personally, I have been seldom so badly bombarded as upon the Zermatt face of the Matterhorn, where every schoolboy knows what happens to the strata. If the rock is known to be good rock, or if we can design a route which by reason of its angle or its salience on the face should be safe, we may chance a few exposed connecting links. But if the rock is notoriously bad, or the disconnections in the safe route look to be numerous, and this especially if they occur high up where the sun will have had long time to act before we reach them, we must not risk the attempt. Years ago our party turned back from completing the ascent of the Furggen ridge of the Matterhorn on the ground of risk from stone fall. Later it was climbed; and the story of the success might be read as a commentary on the mountaineering value of the virtue of renunciation.
Ridges.
The same reasoning from the big to the little helps us in prospecting ridge climbs. If the succeeding edges, towers and large interruptions on a great ridge show a disposition towards maintaining a steady family connection, each with its neighbour, in spite of their bold skyline accidentation—(I cannot put this more intelligibly, but any student of natural outline will know what is meant)—then there is every reason to hope that the ‘cuts-off’ between them will also prove more relenting than they look. In their smaller detail the same indulgences, of ledge and flake and fluke in favour of the climber, will manifest themselves.
A ridge seen end-on is very deceptive. If it rises steeply, it may appear to be a continuous incline, whereas it consists really of separated, ascending ‘steps.’ If a side view is not obtainable, the look of the walls falling on either side from the ridge crest must be our guide. The depth, extent and number of depressions indicated in these side walls, seen in profile, will tell us that there are couloirs below, and therefore probably syncopations in the seemingly continuous crest-line above.
The projection of bulges or articulated ribs on either side wall may, similarly, be identified as the edges or supporting buttresses of isolated towers, whose depth of separation from each other is concealed from us in the foreshortening of the ridge.
Towers on a ridge, seen in flat from one side, are equally misleading. They are more often the ends of short ridges which run crosswise to the line of the main ridge than the needles which they appear to the eye. An inspection of the general lie of the strata will often tell us whether we may assume this to be the case.
If we can get both an end-on view and some oblique view of the ridge, or of any tower upon it, we can reason fairly closely what the two unseen sides of any spire will be like, and even whether they can be expected to offer traverses conveniently sloping, or weathered surfaces, such as the dip of the strata and the jointing deny to us upon the visible sides.
Allowance must always be made for the deceptive outlines that are introduced by foreshortening. A view from some second point is often necessary to counteract their false impression.
In prospecting a ridge for purpose of traverse in the early morning, it is well also to note which side gets the sun soonest and keeps it longest. On this side we shall find the holds most clear of snow or morning glazing, and be able to escape the chill to the muscles of shadow on cold rock. The rock on this side also will, for the same reason, be probably the more superficially disintegrated, and so offer a greater choice of holds, though not necessarily holds of such good quality.
Slabs.
In reconnoitring slabs, on faces or on the side walls of ridges, we find that their apparent angle as seen in face is as misleading as that of snow slopes. In their case we have not the presumptive knowledge that they cannot be as steep as they seem, since rock may be as perpendicular as it looks. Nor have we the subtle variations in light and shadow which help us, on snow, to correct the eye. Rock faces are so broken that it is seldom possible to get the assistance of sun shadows in estimating the angle of portions of their surface.
On the other hand, acquaintance with the characteristics of the particular type of rock, and the visible general inclination of its strata, give us a groundwork for a preliminary estimate of its slabiferous sections.
New snow can again come to our assistance. Snow will reveal to us an easy angle by lying over our slabs as an even cloak; or it may display a vertical section by missing it altogether. It will also indicate the surface in some detail, by the fashion of its distribution on ledge or pocket.
Otherwise we must try to secure a side view of bare slabs, or at least a second, oblique view. If this is not to be managed, it is of use to inspect any near and more approachable slab of similar formation. By an examination of the profile of a ‘sample’ slab we are often able to revise our estimate of the angle and potential holds of its bigger, remoter neighbours.
But on rock the final judgment of doubtful passages must be left in the end to the practical test of attempt. The only infallible criterion is its tactile value. When we have reduced the ‘impossible’ sections of a route to a few isolated passages, it is always worth while going to see. The accidents of rock, its roughness, its whimsicality and its reticences are nearly always in the end in our favour. If we can only make sure that the rock is sound, and fix a general line of ascent, the overcoming of the ‘impossibles’ or the ‘improbables’ in detail can well be left to the moment. If we could map out a whole climb before we did it, much of the pleasure would be lost.
To the resources of rock technique no rock that is sound, and not obviously absurd, is impossible, either by attack or turning movement. And we may assume this to be so until we have ascertained by ‘rubbing our noses against it’ that we have lighted on the rare and unhappy exception.
Rocks in Britain.
In prospecting rock climbs in our own country, reconnoitring is practically confined to scrutinizing familiar faces for alternative routes or to orienting our own climbing in an unfamiliar district.
The first is a simple matter of good glasses, good sense and direct assault. In the second, there is still some room for general discretion.
We have to allow for a great difference in atmosphere as between Britain and the Alps. All alpine measures have to be reduced by about two-thirds.
We can generally assume that the north or northward inclined aspects of British hills will give us the best climbing. This judgment is subject to partial revision, according as we come to know better the local characteristics or the rock formation of the particular hill before us.
If the rock wall faces to the south, our prospect of good continuous climbing is reduced. Rocks facing south will be more disintegrated, as they will have been less protected from the sun and more subject to strong variations in temperature. If broken up or inclined on this side, they will be covered with verdure, which is offensive in itself and hastens the action of water on all the rocks it commands.
We have also to make sure of the lie of the strata, not only for convenience of hold, but also because on the side towards which the stratification dips the moisture fallen on the mountain will drain, and we shall have to look out for our principal enemies—wet rock, rock corrupted by moisture, and, in winter, an icing or glaze.
Our islands provide us with a great variety of rock structure and hill forms, and, according as we get to know the aspects of one hill of any local type, it is interesting to reconstruct the unseen aspects of its neighbours. Several good climbing cliffs were first found in this way.
The look of the outline will suggest the sort of climbing we shall find on the faces. We get further information from the nature and size of any scree slopes below a cliff. The presence or absence of verdure, and the sight of the belts, knots and surface minutiæ, tell us the rest.
All the local rock of the same aspect and in the same structural line will be similar, and may be bad; but if we can get at another aspect of it, on an opposite hillside, it may be of good holding character. For which reason rickety ridgelets may be faced across the valley by sober and admirable slabs.
Mist and cloud in Britain are our frequent companions. Mist may do us good service by throwing an unsuspected ridge or pinnacle into relief. But as a rule the alterations which cloud and fog effect in mountain details falsify rather than reveal. Their use is to place a greater value upon the fidelity with which previous reconnoitring has been conducted, and its result remembered, if we wish, in mist, to arrive at an intended climb at all, or to make descent into the right valley on our return. Not impossibly they are sent by nature to complicate what is otherwise the over-easy mountaineering training of our hills; to handicap the specializing gymnast, and to enforce the practices of observing detail, using the compass and map, and exercising judgment, memory, and the precious sense of direction.