South-Western Part of Somersetshire. 377 



least find abundant proof how very enigmatical the question as to 

 the relative position of strata frequently is ; a question of the first 

 importance in geological inquiries. 



§ 46. On leaving Watchet, the red rock is for a short distance 

 similar to what is found eastward, but veins of gypsum very soon 

 begin to appear, and they gradually increase in quantity. The 

 rock here is of a bright brick red colour, and very friable ; and is 

 traversed in every direction from the top to the bottom by pure 

 white veins of gypsum. Vast blocks of it have fallen down, and 

 are piled above each other and strewed along the shore ; in those 

 that are within reach of the dashing of the waves the gypsum is 

 nearly washed out, giving them a very singular appearance. The 

 rock is not distinctly stratified, but the thickest veins of gypsum 

 are parallel to each other, and nearly horizontal : it contains as 

 usual the grey patches and stripes. The principal veins of gyp- 

 sum are of different thicknesses ; in some places they nearly equal 

 three feet, and the red rock between them is penetrated by smaller 

 veins branching off in all directions ; but besides these there are 

 other veins which traverse the rest in every possible way. There 

 are also detached masses of gypsum which are surrounded on all 

 sides by the red rock. 



There are different varieties of the gypsum ; it is in general 

 white, but it is in some places flesh coloured and bright red. 

 There are thick masses of a very pure compact alabaster fit for 

 many purposes in the arts, and there are several fibrous varieties. 

 In some places it is mixed with siliceous sand and small pieces of 

 quartz, and where these parts are washed by the sea, the gypsum 

 is dissolved, and leaves the quartzose parts projecting and very 

 often in beautiful forms. I did not find it in any case crystallized 



Vol. III. 3 b 



