256 THE BEAUTIES OF NATURE CHAP. 
slope, shows where the water comes to the 
surface, a treacherous covering of verdure 
often concealing a deep pool beneath. From 
this source the rivulet trickles along the grass 
and heath, which it soon cuts through, reach- 
ing the black, peaty layer below, and running 
in it for a short way as in a gutter. Exca- 
vating its channel in the peat, it comes down 
to the soil, often a stony earth bleached white 
by the peat. Deepening and widening the 
channel as it gathers force with the increas- 
ing slope, the water digs into the coating of. 
drift or loose decomposed rock that covers 
the hillside. In favourable localities a nar- 
row precipitous gully, twenty or thirty feet 
deep, may thus be scooped out in the course 
of a few years.” 
If, however, we trace one of the Swiss 
rivers to its source we shall generally find 
that it begins in a snow field or névé nestled 
in a shoulder of some great mountain. 
Below the névé lies a glacier, on, in, and 
under which the water runs in a thousand 
little streams, eventually emerging at the 
~ end, in some cases forming a beautiful blue 
i a ee 
