8 HALF-HOURS IN THE GREEN LANES. 



regions since the climate became milder. It will 

 not take you long to find that a few square feet of 

 the exposed bank of a common tarn will teach you all 

 this, and a great deal more. 



Perhaps you have made your way to this spot 

 along one of the old lanes which botanists and ento- 

 mologists are thankful still remain, and where the 

 stiff boulder-clay crops out in cuttings or along the 

 bottoms of the high banks. There you may read off 

 the same lesson from the enclosed pebbles and 

 boulders as that to which we have drawn attention 

 in the banks of the tarn. This boulder-clay sheet 

 usually occupies the higher grounds, and forms the 

 "heavy lands " of the farmer. Consequently you have 

 been ascending some gentle acclivity in your way 

 along the old lands. If so, you may have noticed what 

 appeared to you evidences of an old leach, in the 

 sloping fields. Nothing could be more pronounced 

 than the terrace-like structure, and not a few good 

 geologists have fallen into the mistake of believing 

 and describing these terraces as the result of ancient 

 river or beach action ! They are, however, nothing 

 of the sort, but they are none the less interesting. 

 And both the geographical and geological student 

 may learn something of the \vear-and-tear of atmo- 

 spherical action on the solid land, by studying them. 

 Let us examine one of these hedge-rows that runs 

 more or less parallel with the valley. They have a 

 wonderful history, these old hedges, especially those 

 which shut in some of the green lanes. To the latter 



