76 Geological Society. 



Sonic three miles north-east of the Colleyweston slate quarries is 

 the high ground of the Stamford Open Field, the summit of which is 

 about 200 feet above the level of the river Welland. In this one 

 hill-mass occur (and may be observed) the whole series of beds 

 from the Cornbrash to the Upper Lias inclusive, the Lincolnshire 

 limestone having reached a thickness of 75 feet, and being the most 

 important bed of the section. 



The limestone which occurs beneath the Great Oolite Clay and 

 above the Upper Estuarine series high up upon the escarpment of 

 Stamford Field, occurs also, at a level some 100 feet lower, at Be- 

 misthorpe, and at Danes' Hill and Essendine, in cuttings of the 

 Great Northern Railway, the only record of the sections of which 

 is to be found in Professor Morris's paper in the Society's Journal 

 for 1853. This limestone has not been considered to be Great 

 Oolite at all ; but the author showed, by a comparison of the whole 

 group of fossils obtained from both beds, that this limestone was 

 identical with the Great Oolite limestone of the Northampton district. 



The author described the peculiar effect of a fault occurring 

 south of the Welland at Stamford, by which the Upper Lias capped 

 by the Northampton Sand has been thrown up to an elevation over- 

 topping the town. Upon a severed and subsided mass the im- 

 portant suburb of St. Martin's has been built, and a peculiar repe- 

 tition of beds has resulted — Upper Lias, Northampton Sand, Colley- 

 weston Slate, and Lincolnshire Limestone being in a double se- 

 quence encountered upon an ascent of the escarpment. The fact 

 was stated that the Colleyweston slate was found near the foot of 

 the escarpment (whence the beautiful Astropecten Cotteswoldice, var. 

 StamfordensiSjVJ'nght, was obtained by the author in 1853), and again 

 upon the summit of the escarpment, at a distance of one third of a 

 mile, at an increased elevation of 150 feet. Other anomalous results 

 of the same fault, which extends some miles eastward, were described. 



The area of the old " Barnack Rag" quarries was referred to. 

 These were in work in the time of the Romans, but had been 

 exhausted for 400 years. The stone (Lincolnshire limestone) Avas 

 the building-stone over a large district in ancient times ; and its 

 excellence was proved by time. 



The escarpment south of the Nene valley at "Wansford presents 

 the same sequence as that of the Stamford Field — Cornbrash to the 

 Upper Lias inclusive. The railway-tunnel is excavated in the Lin- 

 colnshire limestone. East of this, at Castor and Water Newton, 

 and west of the same point at Elton, the Lincolnshire limestone thins 

 away, and the two estuarine series again come together in vertical 

 contact. Along the Nene valley towards Northampton the southern 

 escarpment presents the complete sequence of beds from the Oxford 

 Clay to the Upper Lias inclusive (minus the Lincolnshire limestone), 

 as far as Thrapstone. Here the Oxford Clay and Cornbrash part 

 company and trend southward, the other members of the series 

 (Great Oolite Clay and limestone, Upper Estuarine, Lower Estuarine, 

 and ferruginous beds of Northampton sand, and Upper Lias) con- 

 tinuing on to the Northampton district. 



The author contended that the stratigraphical and palaeonto- 



