found in the Gravel at Starmay, Essex. 351 



highly crystalline and siliceous cement. — 6. A crystalline 

 sandstone of fine texture, interspersed with small fragments 

 of white quartz, rather less in size than those of No. 4. ; both 

 sand and fragments have been rounded by friction, previously 

 to their being united into one mass by a siliceous cement. — 

 7. A black crystalline paste of hornblende, with rounded 

 pebbles of quartz and angular fragments of felspar. — 8. Pud- 

 dingstone: the usual association of sand and common gravel 

 stones, united by a ferruginous or iron cement. This occurs 

 in large irregular masses, and in such abundance, that, for- 

 merly, it was employed in building the walls of some of our 

 village churches. — 9. A variety of the puddingstone. A 

 beautiful variety of this stone is formed by a collection of the 

 small round and nearly uniformly sized black flints and white 

 quartz pebbles, firmly united by a cement formed by finely 

 triturated flint, and cemented by silex. This variety is often 

 cut and polished by the lapidary, and used for ornamental 

 purposes. 



The breccias Nos. 1, 2, 3, 4, and 5. appear to have been 

 transported from a considerable distance ; being in round 

 smooth boulders, and in every way different from No. 6. and 

 its variety ; and so extremely hard, as to require a round- 

 faced hammer of 3 lb. weight, and a strong arm, to break 

 them. Hence it is but natural to conclude that they, when 

 first broken from the parent rock, had rough and sharp aspe- 

 rities ; which a rolling action, long continued, has reduced to 

 their present shape and condition. 



Chert. — In large and small boulders; in some of which 

 are good specimens of E'ntrochi, or screw encrinite (figured in 

 Mag. Nat. Hist., iv. 376.), from the mountain or transition 

 limestone. 



Chlorite slate. — In laminated boulders, very much like the 

 Westmoreland slate. 



Green or Chlorite Sand. — Two boulders only of this stone 

 met with : those very hard and compact, yet with all the 

 mineral properties of the rock called Kentish rag. 



Sandstone. — In numerous boulders of fine and coarse tex- 

 tures ; some with mica, others without it : in some are found 

 casts of bivalve shells. 



Organic Remains of ike Chalk in Flint and Chalcedony 

 from the Gravel. — Folypi : Ventriculites BennettzV? Mant., 

 Geol. Suss., tab. 15. fig. 3. : chalcedony. Ventriculites; in 

 shape like the former, but larger : flint. V. radiatus Geol. 

 Suss., t. 14. V. radiatus: radical process of, or stirps, Mant. 

 Geol. Suss., t. 13. f. 2. and 3. cal. V. quadrangularis, Mant., 

 t. 15. f. 6. [We may here observe, for the sake of the 



