A HISTORY OF NORTHAMPTONSHIRE successful in its object, the incidental information then obtained is most interesting. An abbreviated section is given below. Top of Section at Orton in bed from sea-level Upper Lias, including soil and silt Middle and Lower Lias RHitTic (White Lias and Black Shales) Keuper : Sandstone and Breccia Old Land Surface Volcanic Rock : Quartz-porphyrite showing an eroded surface ; distinct cleavage at an angle of i8° with the axis of the core . Greatest depth Quartz-porphyrite (or dacite ?) occurred in both the Keuper breccia and Rhastic conglomerate (White Lias), clearly indicating that after the volcanic rock at Orton had been covered with newer deposits the same rock was still exposed not far away ; that is to say, Orton was not the highest part of the volcano, or not the only one. The Cambrian and Silurian Periods The Cambrian and Silurian periods may be passed over with the remark that, considering the relatively small thickness of the earth's crust at present pierced by borings in Northamptonshire, and for other reasons, one or both of these formations may be supposed to occur below the ascertained rocks. The Old Red Sandstone (?) The oldest stratified rocks that have been encountered in situ in Northamptonshire consist of coarse red sandstones, grits and marls, beheved by Mr. Etheridge to belong to the Old Red Sandstone period, though, as remarked by Prof Judd, they may belong to the Carboniferous formation ; in the absence of fossils the point must remain undecided. Prof. Bonney says that undoubtedly the material was derived from granitoid rocks of Archsan age.' The rocks here referred to were encountered in the deepest boring so far made in Northamptonshire (994 feet), at a place near to the canal and railway between Gayton and Bugbrook, some five miles south-west of Northampton, and two miles north-west of Blisworth station. The boring was a trial one for water by the Northampton Waterworks Company. As with the Orton boring, an abbreviated section is given from information then obtained.
- Henry John Eunson, 'The Range of the Palseozoic Rocks beneath Northampton,'
Quart. 'Journ. Geol. Soc. (Aug. 1884), vol. xl. p. 492. 4
