162 Pattison— Formation of Tallies. 



The plateau bears no mark which offers the slightest reason why 

 the four or five tiny streams should have originally flowed in one 

 direction rather than another. But the crust of the plateau has 

 been broken up in the direction of the valleys, and the uppermost 

 reaches are incumbered by untravelled blocks of the grit which 

 have been somehow broken in situ and then left. What effected 

 this operation? Certainly not denudation, not rain or rivers, not 

 atmospheric agency. These are minor polishing agencies, but they 

 could never originate the basis of their operations. Not ice, for 

 there is no trace of glacial grinding action. Looking from this 

 summit level at the diverging lines of ruin, one would say, here we 

 are at the spot where force has come to its vanishing point. Some 

 great poimding and crushing and disturbing operation has radiated 

 from the line of the river vallies below, and spent itself in the 

 everlasting hills ; the maximum of the force was displayed at the 

 base, in the main valley below, and its minimum up here at the 

 summit ; the intervening wedge of material was shattered and 

 loosened, leaving to rain and rivers the operation of its removal. 

 The latter have done the barrow-work, but the powder- work was 

 first done. After descending through about 100 feet of grits we 

 come to the shales (Plate and grey beds), in which the stream 

 becomes more peaceful, we then re-enter a sandstone sill, down a 

 succession of steps, in which the perpendicular is formed of shales 

 and the steps of grit, the former constantly yielding and the latter 

 breaking, so as to deepen the gorge, now in one place and then in 

 another. Crossing the thin fell-top limestone, we came into a well- 

 marked succession of slate sills and grits. On looking around we 

 see that the tiny rivulet has, and has always had, a definite course. 

 True, it skips about, now here and now there, within limits of a 

 dozen yards, now coursing down one channel and then another, as 

 its broken ledges, or as floods determine, but its course is at the 

 bottom of the gorge, and is quite distinct from the gorge itself, 

 which has sloping sides ; it is a water staircase, like the celebrated 

 Cascade at Chatsworth, but with smooth inclined side walls. The 

 whole dip of the strata is eastward, and therefore if the valley had been 

 excavated by water or by rain it would have gone in the direction 

 of the first shale bed, and been marked by an overhanging cliff of 

 grit in its down eastward course. On reaching the limestone, which 

 is here called the Great Limestone (the cliffs of which gives name 

 to the middle of the little valley, the Skears, but which is not the 

 Scar limestone of other districts) we find a beautiful development 

 of the cutting-back power of the water. The beds of the limestone 

 have first been worn quite smooth, leaving the corals and Brachiopods 

 in exellent relief, the spray has hollowed out the shales beneath, the 

 limestone has given way, the rivulet has suddenly acquired a new 

 level, the old bed with its lips and pot-holes and curved lines is left 

 dry, like a broken well-dish. This action is confined to the staircase ; 

 it does not extend back into the side slopes, The amount of river 

 bed thus acted on is very considerable. Judging from rough 

 calculation, it must have been going on for ages before the Boulder- 



