Vol. 69.] AGE OP THE SUFFOLK VALLETS. 605 



Other borings put down in Ipswich and the neighbourhood since 

 the last list, published in 1906/ prove the Chalk to lie at the 

 customary levels ; but a boring begun in December 1912, and 

 finished early this year (1918), immediately west of the town, 

 proves the extension of the buried channel farther westwards. 

 I was able to see the early part only of the boring, and I have 

 to express my gratitude to my friend, Mr. Slater, who, being on 

 the spot, carefully made detailed notes and kept samples of all the 

 beds met with. I have used his notes freely in the following : — 



Boring for water for the Diesel Engine- Works by the river 

 immediately west of the 'town. (Height above O.D. = 23 feet.) 



Ri ver-Te rr ace. 



Drift. 



Thickness Depth 



infect. in feet. 



( Red dish sand 4 4 



{ Ferruginous flinty gravel and sand ... 25 20 



(Siltyclay .' 21 50 



| Sharp, dark-grey sand, with specks of 



chalk 8 58 



Do.,butfiner 7i 65^ 



Similar sand, but with potato-sized 



boulders of chalk and flints 9| 75 



Coarser grey sands 17 92 



Chalky flint - gravel ; some quartz 



boulders 5 97 



Chalk (remanie material) li 100 



Coarse gravel 4 104 



Chalk (as before) 6 110 



Very coarse gravel .. o 113 



Chalk 112 225 



The first 29 feet is typical terrace-material, with iron-stained 

 and much-altered flint, of a prevalent reddish or brownish tint. 

 The grey sands and silts from 50 to 65| feet are, from the samples, 

 obviously washes from the Chalky - Ivimeridgic Boulder Clay : 

 hence their colour. The uppermost 8 feet of this is a micaceous 

 sandy loam. Two boulders of Chalk were passed through (from 

 97 to 100 feet and 104 to 110), consisting of rubbly altered 

 material like the transported boulders at Little Cornard (see p. 596). 

 Mr. Slater has recorded a huge transported boulder of Chalk, 

 42 feet long, higher up the valley at Clavdon.'- The 4 feet of gravel 

 between the two Chalk masses is rather peculiar. It consists 

 of a great deal of flint, much of it in the form of fine chippings, 

 in a matrix, of chalky sand. This flint is brown and black in 

 colour and very fresh, even the thin translucent edges being un- 

 altered, though perhaps a little rounded. All the flint in the Drift 

 portion below the terrace -material is fresh and unaltered, just as 

 it came from the Chalk. Vein-quartz pebbles frequently accom- 

 pany it; but it is the last 3 feet of gravel, resting directly on the 

 Chalk, that is the most interesting and important part of the 

 section. This gravel consists of fresh dark -brown and black flint- 

 pebbles, about 3 inches in diameter, many of them beautifully 

 rounded, but still showing over parts of them the original white 



1 Op. cif. 2 Slater, 1907 (22) pi. v, fig. 7. 



