14 Canon Bonnetj — Moraines and Mud-streams in the Alps. 



•visible from the valley, since the upper parts of the mountain are 

 concealed hereabouts by their lower buttresses. But occasional 

 glimpses are obtained of a mass of pale-coloured schists, which no 

 doubt extends for a considerable distance, and is perhaps identical 

 with one which I remember to have seen near the entrance of 

 the Vispthal. 



The earth pillars of the Katzenbach and the Finsterbach have 

 long been famous. These are in upland valleys, high above that of 

 the Adige, on the flanks of the Eittnerhorn. As they have been 

 so frequently described, a few words about the material will be 

 sufficient. The matrix is a red earth, which becomes hard in 

 drying, and has probably been supplied by the destruction of the 

 well-known 'porphyry.' Most of the smaller stones are more or 

 less rounded, even the big blocks (up to 50 or 60 cubic feet) being not 

 unfrequently subangular. Stones of any conspicuous size are not 

 very numerous ; it would not be difficult to find a cubic foot of 

 material without one bigger than a marble. Once or twice I saw 

 signs of stratification, and the larger boulders seemed often to occur 

 in layers. The relation of these masses of debris to the slopes on 

 either side and to the upper part of the mountain itself satisfied me 

 that the ridges and pillars had not been carved out of mounds, but 

 from material which had been deposited so as to partly fill up 

 a valley already excavated in the 'porphyry.' On my first visit 

 I came to the conclusion, with which my companion, the late 

 Mr. W. Mathews, agreed, and which was strengthened on a second 

 examination nine years afterwards, that this material, though very 

 likely incorporating moraine stuff, was not true moraine, but had 

 descended into the glens from above, and thus was more or less 

 of the nature of mud avalanche. 



Though these deposits of muddy debris often are not easily 

 distinguished from true moraines, the question may occasionally 

 be settled at once by the correspondence between the materials 

 and those in situ on the mountain side above; but as these slips 

 (so far as I know) are always later than the final retreat of the ice, 

 they may have carried down with them and incorporated moraine 

 and perched blocks. As a rule, however, in one of these deposits, 

 the finer material bears a larger ratio to the boulders than is usual 

 in true moraines under similar conditions. In them, as far as my 

 observations go, this ratio increases with the distance from the head 

 of the valley. But the material in three, at least, of the districts 

 named above — in the Eringerthal, in the Vispthal, and in the upland 

 valleys on the Eittnerhorn — resembles what we should expect to 

 find in moraines on subalpine or even lowland regions. The form, 

 however, is a more characteristic feature. A moraine in its natural 

 condition is more or less of a mound. These flood deposits either 

 shelve gently up — like all slopes of debris — to the cliffs and glens 

 down which they have descended, or fill up the bed of the main 

 valley to a considerable depth.^ The latter any ordinary terminal 



1 As is the case with the trass which still remains in places in the Brohlthal (Eifel). 



