LOCAL FEATURES. 15 



No. 3. Upper Drift. The Upper Boulder Clay covers all 

 the high lands to a considerable depth, and forms the principal 

 feature of the neighbourhood. Its stiff plastic substance is 

 employed in brick-making, and in the manufacture of "clay 

 lumps," a local process in which it is mixed with chopped 

 straw and dried in the sun, after the manner of the ancient 

 Egyptians ; as marl, it is used for manure on cultivated lands. 

 Owing to atmospheric influences the clayey element in this 

 formation is often washed out, leaving a thin layer of stony 

 gravel and sand on the surface, which alters the apparent 

 character of the district, as at Starston Brickyard. Fossils, 

 derived from older formations and chiefly from the Chalk, Oolite 

 and Lias, are common, and in some cases well preserved. Mr. 

 Candler has obtained from the drift in this neighbourhood 

 vertebrae of Ichthyosaurus and Plesiosaurus, and examples of 

 the following genera of echinoderms and mollusca : Anan- 

 chytes, Micraster, Ammonites, Belemnites, Gryphcea, Inocer- 

 amus, Ostrea, and others.* The clay contains manganese and 

 a good deal of iron, which sometimes appears in the form of 

 large nodules, and percolates through the underlying sands 

 and gravels, giving them a reddish-brown colour. 



The remaining two formations belong to the Becent and 

 Post-Glacial Periods,! and are the earliest in which unques- 

 tionable traces of man's existence have at present been dis- 

 covered. 



No. 2. Ancient Valley Gravel. This is the older, and con- 

 tains bones of animals now extinct. It is found at various 

 points in the vicinity of the Waveney valley, sometimes with 

 traces of river loam or brick-earth, which is worked for brick- 

 making, as at Hoxne. It was probably formed, however, by 

 the action of rivers before the existing physical features of the 

 district were developed, and when the valleys were full of 

 melting ice consequent on the change of temperature. In 

 those early times, as Messrs. Whitaker and Dal ton suggest, 

 " the brooks from the South Elmhams, Metfleld, and Fressing- 

 field may have fed, not the "Waveney, but the Little Ouse, as 

 indicated by the westward trend of their channels, and by 



* " Examples of the above-named genera occur in the Eedenhall Road 

 Brickyard pit. Gryphcea incurra, a shell from the Lias, is perhaps the 

 most abundant and characteristic fossil of the Upper Boulder Clay at 

 Harleston." C. C. 



t "I think that many of our so-called 'Post-Glacial' beds are Post-Gl&cial 

 only in the sense of being more recent than the Chalky Boulder Clay. The 

 latter formation, however, only marks the climax of the 'Great Ice Age,' 

 and we know from the ' Purple Boulder Clay,' and ' Hessle Boulder Clay ' of 

 Yorkshire, that twice since that climax northern England has been buried 

 beneath an advancing ice-sheet. To one or other of the two intervening 

 temperate periods some at least of our ' Post-Glacial ' brick-earths and 

 gravels will perhaps be eventually assigned." C. C. 



