A HISTORY OF NORTHAMPTONSHIRE 



developed and old ones permanently deserted. These old valleys filled in 

 with Boulder Clay or Glacial Gravel have, not inaptly, been called buried 

 valleys. 



Buried Valleys 



Buried valleys are by no means uncommon, but only occasionally 

 can they be traced for a sufficient distance to make out the original source 

 and particular destination of the water they carried, for they are not 

 noticeable till the ground is opened. A buried valley near Northampton 

 extends from the Wellingborough Road to the Billing Road, under 

 Abington Abbey, and evidently debouched into the Nene. The trough 

 is some 200 yards wide, depth unknown, and is filled with a jumble of 

 materials not greatly water-worn, none being older than the Northamp- 

 ton Sand. On the Wellingborough Road Great Oolite limestone largely 

 preponderates, on the Billing Road there is more clay, and Kimeridge 

 Clay fossils are rather abundant. 



At Furtho, towards Stoney Stratford, an old valley of the Ouse has 

 in its midst Boulder Clay to a thickness of 100 feet or more, which the 

 small post-glacial streams have not been able to remove.' Numerous sand 

 and gravel deposits would probably come under this head, including the 

 sand beds in the parishes of Milton and Courteenhall referred on page 23. 



The Nene Valley 



The following remarks with respect to the Nene valley would apply, 

 with modifications, to the Welland or other large watercourses. If we 

 stand on any of the bounding hills of the Nene valley below Northampton 

 and look at the deep, wide excavation, and then at the thin, scarcely dis- 

 tinguishable stream meandering through the flat meadows, and if we fur- 

 ther take account of the occasional great floods, it is difficult to conceive 

 that the river and the floods could have produced the results observed, for 

 the river has little or no excavating power, and floods generally, if not 

 always, deposit more silt in the valley than they carry away out of it ; in 

 fact the river and the valley are misfits. Now since the drainage area 

 above any selected point was never more, and even may have been much 

 less than now, we have to look back for a suitable time and adequate cause 

 for a small river in a large valley, and both we find at the end of the first 

 stage of the Glacial and the beginning of the Inter-glacial periods. The 

 rapid melting of the first ice sheet, which left a capping of gravel over 

 even the flat lands of the county, produced floods immense in volume and 

 of great velocity in this valley, being perhaps equivalent in effect to a heavy 

 rainfall over the whole watershed for a very long time, at first without any 

 exposed porous rocks to help in its disposal by absorption, and later only 

 saturated ones. These floods carried away all the finer material of the glacier 

 ice, deepened the valley by excavating the clay bottom, widened it by 

 washing away the sides, in which they were aided by frequent slips of the 



' Beeby Thompson, ' Pre-glacial Valleys in Northamptonshire,' Journ. North. Nat. Hist. 

 Soc, vol. ix. p. 47 (June, 1896). 



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