The Half-seen
In the Alps or unfamiliar regions, to discover the truth about what may be termed the half-seen,—that is, about formation or detail which should be visible but for foreshortening, distance, angle or light,—new snow is again our best auxiliary. Its presence suggests, even emphasizes, much that is unsuspected. Seemingly straight ridges are shown to be crooked, and plain faces rough. It helps us with light in hidden corners, and annihilates distance.
Otherwise we have to use days of driving cloud, or wait for the morning or evening moments of thin mist, when the drift lies across the face or through the ridge, and picks out its angles, features and perspective. Mists will often reveal the existence of ridges and pinnacles, whose separation from the face behind is undiscoverable as seen in front or in clear light.
Of more frequent service are the hours when the sunlight falls across the face from the side, and the protuberances and hollows jump into stereoscopic clearness in shadow and the modifications of light. Invisible snow depressions, bosses and foreshortened angles of rock slab or ledge are cheerfully betrayed by the veracity of cross-shadows; and points and lines of obstinate sunlight, which remain salient and surprising after the sun has deserted all the rest of the seemingly even surface of snow or rock, proclaim to us unexpected inequalities and therefore possibilities of passage.
In cases of outside difficulty upon rock, where we are reconnoitring some great rock wall, of a granite or dolomitic type, we can generally make sure of the vertical rifts and clefts from below; but the presence or size of transverse fractures or belts is hidden from us. In this case assurance as to what has been only half-seen can be completed if a downward view of the rock, or of its local type, is also obtainable. The information is best secured from the summit of the peak itself, reached by another route, and many great first ascents have owed their discovery and safe accomplishment to such complementary inspection. Only a short section need be in sight from above in order to indicate the general character of the cross belts, and the last section on such peaks is always the more important to examine, as it will generally be the severest in its details. But even without this local visitation a downward or oblique view of any section of the face, or of an allied or neighbouring wall of similar structure, will give adequate information, and convert the half-seen into the two-thirds made certain.
A familiar instance of the use of such inspection would be almost any great Welsh cliff or Irish sea cliff. Seen from below, it appears to be continuous steep slabs, with only vertical cracks for the climber; seen from above, it looks a jumble of vague cross-terraces of grass, snow or rock, hardly offering a chance of good articulated climbs. Both estimates would be false. Only by collating the two points of view can a fair judgment of the character of the climbing be formed. A number of delightful climbs, of late discovery, have owed their neglect to the fact that they were only easily visible from a single aspect, and that this produced an abiding false estimate of their quality. The importance of securing corrective views, from different angles, be it only of a section of a proposed route, or of a passage of similar character more conveniently situated, attaches also to our inspection of the half-seen on big ridges. With points to remember in such inspection I have already dealt.
It does, in fact, belong not a little to the reasoning from the seen to the unseen; to which more metaphysical division of reconnoitring it leads over.