GENERAL ACCOUNT OF THE DEPOSITS. 7 



Numerous variations from the above type of sections were 

 found in the different workings around Upware. There may be 

 three distinct phosphatic nodule beds and apparently all these 

 may in places unite into one (Walker). The lower bed may be a 

 simple pebble bed instead of being hardened here and there into a 

 conglomerate, and it may be separated from the junction line of 

 the Jurassic rocks by the interposition of a bed of sand. 



For the further illustration of the Upware deposit, under a 

 somewhat different aspect, the new working recently opened out 

 at Spinney Abbey is worthy of being described, for the sections 

 in this border-district of the Upware area have never yet been 

 recorded. 



I observed this section in August, 1879, in company with 

 Mr E. B. Tawney, M.A., F.G.S., of the Woodwardian Museum, 

 when we found the new pits close to a farm some 500 or 600 yards 

 east of the Spinney Abbey Farm. 



The section was as follows: — 



ft. in. 



(3) Brown surface earth 1 6 



(2) " Head " of blue clay 9 



(1) Irregular gravelly zone, the pebbles being mostly flints and 

 coprolites about 3 



(4) Blue, yellow, and coarsely mottled plastic clay, with scattered 

 coarse quartz and other sand grains, and numerous sandy 

 concretions 2 



(3) The 'silt bed' — a chocolate-brown and yellowish sand passing 

 into a sandy clay, which is rather coarse, loose, and like an 

 ordinary shore sand. It consists principally of quartz and 

 iron grains. A few irony sandstone nodules are scattered in 

 the bed. This bed passes gradually into bed (4) 2 



(2) The " Upper Coprolite seam." A pebble bed of phosphatic 

 nodules, Lydian stone, chert, quartz, and other pebbles as 

 big as beans, packed in loose iron-coloured sand. Some 

 irony concretions occur in its upper part, where it passes into 

 bed(3) 2 



(1) The "Lower Coprolite seam." A thin band where the 'copro- 

 lites' are darker and better than in the upper seam. The 

 sandy matrix is hardened almost to a 'rock' by carbonate of 

 lime, which was probably derived from the underlying bed (a) 3 

 a A calcareous grit of corallian age. It is a hard, gritty, bedded lime- 

 stone ; grey coloured, with scattered large oolitic grains ; no 

 fossils seen. 



The clay bed, No. 4, looks at first sight very much like the 

 gault clay, but although beautifully ductile it is seen to contain an 



