THE PROBLEM OF LYNCHETS. 



They refer to a lynchet on a chalk hill between Osmington 

 and the sea. This fine grassy terrace, 18 feet wide, is a dead 

 level from side to side, though lengthwise it slopes decidedly. 

 The upper bank hos an angle of 39° and the lower of 31°. The 

 underlying hard chalk, itself a lynchet, has the unusual feature 

 of a slight dip imtm'ds, though only of 2°, for the most part of its 

 width, beyond which it falls away at an angle of 20° ; and even 

 this increases just under the edge of the terrace. The material 

 that lies between the thin crust of humus, on which the grass 

 grows, and the hard chalk below is a fine chalk rubble of con- 

 siderable quantity, especially abundant along the very edge of 

 the terrace, where it is 33 inches thick ; whereas along the inner 

 border it is only three inches thick. To the eye this rubble is as 

 white as the hard chalk itself, but in a photograph it looks a 

 shade darker. If this were an accumulation of humus, ploughing 

 might have caused it. Way we regard it as possible that a 

 mixture of humus and chalk may in time lose all signs of the 

 former and acquire an altogether chalk-like appearance ? 



21. The coach road between Dorchester and Weymouth was 

 made about 70 years ago, and the summit of the Ridge was 

 lowered by a cutting. In this operation the excavated material 

 was thrown out upon the surface soil, which was thus shut in 

 between two masses of chalk. Recently, in quarrying for road 

 repair, a section has been made, that is still open to view, of the 

 imprisoned earth, and no perceptible bleaching is apparent even 

 by photography. It is sketched on Diagram J. 



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