XV 



THE STORY OF SOME PEBBLE HILLS 



" The Hills are shadows, and they flow 

 From form to form, and nothing stands ; 

 They melt like mist, the solid lands, 

 Like clouds that shape themselves and go." 



TENNYSON. 



streets of a large town have for rest. We notice that the southern 

 been projected till they reach side of the hill is very steep. What 

 within a gunshot of this pebbly hill, up the geologist calls the angle of repose 

 whose steep, shivering sides we have just is very high, nearly 30 from the hori- 

 climbed. We are some 400 feet above zontal walk across the flat table top, 

 sea-level, and, looking northwards over and the northward slope, along the 

 the lower ridge of the London Clay, dip or inclination of the strata, is seen 

 on which stands the glass palace of to be much more gentle. 

 Paxton, through the faint haze the During the ages a slight thickness 

 blurred outlines of London landmarks of peaty material has insinuated itself 

 may be discerned. Away to the south, among the pebbles, affording roothold 

 the billowy chalk downs rise gradu- for gorse, bracken and bramble. Strik- 

 ally upwards to their escarpment on ing deeper down, the Scotch pine with 

 the sky-line. its rugged red bark, and the more 

 The capping of pebbles rests mani- delicately-featured fir thrive abun- 

 festly on a layer of fine, sharp, grey dantly. The former tree has half- 

 sand, and the loose stones have rolled rounded leaves, grouped in twos ; the 

 downhill nearly to the foot, leading oblong needles of the fir, flat and blunt, 

 one to think that the whole is one are strung in a double row. Scrubby 

 homogeneous mass. Below the sand lie oaks grudgingly fill up the interspaces 

 clays, alternately mottled and blood- between the conifers, and cover the 

 red, interrupted by beds of gravel loopholes between their stems. 

 and buff sands. Under all is the The dull purple-black pebbles will 

 foundation of solid chalk. Since the well repay investigation. Almost every 

 crown lies on the unstable sand, the one is of flint, and must, at some time, 

 hill creep of pebbles has gone on have been derived from the chalk, 

 until the rambler finds the ascent A quartz stone, although practically 

 toilsome, and the panting lungs crave of the same chemical composition, is 



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