Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/522

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series ; to exhibit fossils gathered from each ; and thus to contribute somewhat towards the establishment of the character and sequence of the Oolites of this Midland District.

I purpose to divide my work into two or more Parts, and the present Memoir will constitute the first of these ; but it is not improbable that the publication by the Geological Survey of their maps and memoir of the northern division of Northamptonshire (the work of that excellent geologist, Mr. Judd) may intervene, and render superfluous the completion of my scheme. In the meantime the following may not be unacceptable.

Part I.

The Oolites of Northampton and Neighborhood.

Northamptonshire, from of old, has been said to be famous for " springs, spires, and squires." The first of these characteristics directly, and the others more remotely, are attributable to the geological features of the county.

The double alternation of pervious beds overlying impervious ones — the limestone of the Great Oolite upon its underlying clay, and the Northamptonshire Sand upon the clay of the Upper Lias — produces, at the outcrop of those beds upon the escarpments of the numerous valleys which intersect the county, the springs of pure water which formed the subject of the ancient boast.

Then the variety of its soils (answering to the variety of the underlying materials), its fertility (attributable in part to natural irrigation), and the broad meadows with which its valleys are floored led at an early date to the general cultivation of its surface, and to its partition into small holdings or lordships : hence the numerous villages with which the county is packed, and the consequent churches and spires (built almost wholly of county Oolitic stone) with which it is studded.

Lastly, from the undulating character of its surface, and its fertility, eligible and beautiful sites for residences abound ; and many such there are, with parks and " pleasaunces," (some of palatial importance,) constituting the ancestral homes of a numerous landed proprietary, and investing this Midland shire with not a little of dignity and beauty.

On the high grounds are commonly found deposits of Older Postglacial, or Glacial Drift, in the form, at some places, of gravel, and at others of Boulder-clay ; which Drift-beds, having been cut through in the formation of the existing valleys, are therefore of a higher antiquity than they, and indicate that the causes which operated to produce the present surface contour originated subsequently to the Glacial period.

These numerous valleys have generally cut through the whole of the Oolitic beds, often deep into the Upper Lias, and in some in- stances even through the Marlstone into the Lower Lias ; and this circumstance, and numerous excavations — in the shape of stone, slate, sand, ironstone, and clay pits, road-cuttings, and railway-cuttings — offer many facilities for geological investigation.