394 CRETACEOUS. 



which afford the whetstones are about eighty feet below the top of the hill, and the 

 scythe-stones are shaped from concretions of very irregular form, embedded in 

 looser sand, but marks of the stratification of the sand can be traced on their out- 

 side. The masses of stone vary from six to about eighteen inches in diameter, and 

 the beds whicli afford them attain a total thickness of about seven feet, of which 

 about four are fit for that purpose, the looser stone at the top and bottom being 

 employed for building.^ 



At Penzlewood (Pen Selwood) near Stourton, similar beds (Penstone) liave been 

 worked for scythe-stones at the Pen pits.- 



From the neighbourhood of Seaton the Upper Greensand 

 extends westwards in outlying masses to Sidmouth and the Haldon 

 Hills in Devonshire. A shingle bed was noticed by Mr. Godwin- 

 Austen in the lower part of the Greensand on Salcombe Hill.^ 



A yellow sandstone belonging to the Greensand, and known as the Salcombe 

 sandstone, was, until about iS6o, largely employed for building-purposes. The 

 old quarries (I am informed by Mr. P. O. Hutchinson) were worked on the side 

 of the hill east of Salcombe Regis church, near Sidmouth. Much of Exeter 

 Cathedral (it is believed) was built of this stone. 



The Upper Greensand on Little Haldon is about 70 feet in 

 thickness ; there the Chert-beds are mostly in a disintegrated 

 condition. At Smallacombe Goyle, on Little Haldon, there is a 

 bed (O/'bi/oh'na-chert) with O. concava, which forms a higher 

 horizon, according to the Rev. W. Downes, than is met with at 

 Blackdown. Many fossils have been obtained at Great and Little 

 Haldon by Mr. W. Vicary ; they include Patuncidus wnbonatus, 

 Pecien quadricostatus, also many Corals.* 



Most of the deposits, at one time regarded as Upper Greensand, 

 near Newton Abbot, are commingled with gravel -beds containing 

 pebbles and blocks of flint and chert ; traces of Greensand in situ 

 may, however, occur on Haccombe Hill, and near Sandy Gate.^ 

 How far the Upper Greensand originally extended to the west is 

 very doubtful, so much denudation having taken place since, but 

 the occurrence of chert-gravel at Orleigh Court, near Bideford, 

 suggests the former extension of the Greensand over a great part 

 of Devonshire. It is probable that the formation owes its origin 

 largely to the destruction of the older stratified and igneous rocks 

 of Devonshire, some of which formed cliffs on the borders of the 

 Greensand sea, and perhaps in great measure to the destruction of 

 granitic rocks, the decay of which now gives rise to a quartzose 

 sand not unlike some varieties of the Greensand. 



The economic products of the Upper Greensand have been previously noted ; it 

 is usually a water-bearing formation. 



1 T. G. S. (2), iv. 236. 



- See Midland Naturalist, vi. 98 ; and Rev. H. H. Winwood, Proc. Somerset 

 Arch, and Nat Hist. Soc. xv. 



■' T. G. S. (2), vi. 449 ; P. G. S. iv. 197. 



■* See Downes, Q. J. xxxviii. 91 ; P. M. Duncan, Q. J. xxxv. 89 ; also De la 

 Beche, Report, p. 247. 



* CJ. J. xxxii. 230. 



