130 Reports and Proceedings — 



of the wedge of the Lincolnshire limestone is seen to come in ; and this sequence, 

 for the first time, is presented : 



Great Oolite Limestone. 



,, ,, Upper Estuarine Clays. 



Inferior Oolite Lincolnshire Limestone (very thin). 



„ „ Lower Estuarine Beds ) JSTorthamptoa 



„ „ Ferruginous Beds j Saud. 



Upper Lias Clay. 



The same sequence, with the occasional superaddition of the Great Oolite Clay, 

 was shown to be repeated upon the western escarpment of the Ise, at Glendon, 

 Barford Bridge, near Ruckingham, at Weekly, and at Geddington (the Lincolnshire 

 limestone increasing in thickness at every advance), and to occur over and over again 

 upon innumerable escarpments in the counties of Northampton, Rutland, Lincoln, 

 and York, oifering unmistakable and incontrovertible evidence of the true strati- 

 graphical position of the Lincolnshire limestone. 



'Ihe author described the section in the ancient quarries at "Weldon, whence is 

 obtained the highly reputed freestone of that name. He exhibited a diagram of the 

 horizontal section from Rockingham, on the "Welland valley (which marks to the 

 north-west the line of division between Northamptonshire and Rutland), through 

 "Weldon, by Oundle, and across the Nene valley into Huntingdonshire. It was 

 shown by this diagram that, although the Lincolnshire limestone has a thickness of 

 some 30 feet at Weldon, it thins out very rapidly eastwards, being nowhere found 

 within three miles of Weldon in that direction, and being altogether absent from the 

 Nene escarpment at Oundle, which presents, with this exception, the whole series of 

 beds from the Oxford Clay to the Upper Lias Clay inclusive. 



The author successively described sections in the Lincolnshire limestone — at Kirby, 

 where the equivalent of the CoUeyweston slate is quarried, this being the extreme 

 western point at which it has been found; at Deene, Wakeiiey, Morcot (where the 

 whole series from the Cornbrash to the Upper Lias inclusive occurs, the Lincolnshire 

 limestone attaining to a thickness of 60 feet), Ketton (where the famous Ketton 

 freestone is quarried), and CoUeyweston. At the last-named place the well-known 

 calcareo-arenaceous slate has been quarried for more than 350 years ; and the 

 numerous quarries occupy an area exceeding a mile in diameter. Here everywhere 

 may be noted the position of this slate-bed, which bases the Lincolnshire limestone 

 series, and immediately overlies the Lower Estuarine Sands. 



Some three miles north-east of the CoUeyweston 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 occurs (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 Belmisthorpe, and at Danes' Ilill 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 was not formerly 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 overtopping the town. Upon a severed and subsided mass 

 the impbrtant suburb of St. Martin's has been built, and a peculiar repetition of beds 

 has resulted — Upper Lias, Northampton Sand, CoUeyweston Slate, and Lincolnshire 

 Limestone being in a double sequence encountered upon an ascent of the escarpment. 

 The fact was stated that the CoUeyweston slate was found near the foot of the escarp- 

 ment (whence the beautiful Astropecten var. Stamfordensis, Wright, 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 



