174 



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By the Rev. T. Peekins, M.A., Head Master of Shaftesbury School. 

 (Read before the Society at Shaftesbury, August, 1884.) 



GLANCE at the map of England in which the chief 

 groupings only of the geological formations are indicated by 

 different colours is sufficient to show that the town of Shaftesbury, 

 where we are assembled to-night, is in the centre of a most in- 

 teresting district, if diversity of geological formation lends interest 

 to any place. 



Not many miles to the south-west the trias, or new red sandstone, 

 starting from the neighbourhood of Sidmouth, stretches — though 

 much interrupted by other rocks — in a north-easterly direction, to 

 the Midlands, where, divided by the coal-fields of Derby, it branches 

 out to the mouth of the Tees, on the east coast, and the mouth of 

 the Dee, on the west. Then, again, to the east of the trias, and 

 therefore nearer to Shaftesbury, we see on the map the irregular 

 ragged-edged bands representing the different members of the lias 

 and oolite. Then, again, in the southern part of Dorset, and again 

 to the immediate north-east of Shaftesbury, we have the marine 

 beds of Portland, with their excellent building stone, overlaid by the 

 fresh water beds of Purbeck. 



Then Shaftesbury itself stands upon the upper greensand, a 

 member of the cretaceous system, while the chalk — another member 

 of the same — rises into " the long backs of the bushless downs," 

 which, when the shadows of passing clouds chase each other across 

 their softly rounded forms, give such a charm to our scenery ; and 

 then, further to the south, you find that the lower members of the 

 tertiary system are also represented on the map. 



But when we turn our attention from the general map of England 

 to one drawn on a larger scale, such as the Ordnance Map which 

 represents a mile by an inch, in which the sub -divisions of the 



