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The Museum Gazette 



NATURAL HISTORY NOTES AND EXTRACTS. 



Clay-with-Flints. 



On some parts of the chalk downs, occurring in isolated 

 patches, but never forming large and even beds, may be 

 observed a peculiar deposit of stiff brownish clay, contain- 

 ing a large number of unworn flints, and sometimes flint 

 pebbles and quartz fragments. Such a deposit may be 

 observed on the chalk hills around Hawkley, near Peters- 

 field, and in many other places. Its thickness is very 

 variable, in some places not exceeding a foot, in others not 

 far removed the clay may be 25 feet high. 



The origin of this deposit has been described by Mr. W. 

 Whitaker, F.R.S., in his well-known work on the " Geology 

 of London." We quote the following paragraph from page 

 282 :— 



" Clay-with-flints is of many ages, and may be forming 

 even at the present day, and that it is owing in great part to 

 the slow decomposition of the chalk under atmospheric action. 

 If a chalk district were exposed for thousands of years, as 

 many such districts must have been, to the action of rain, 

 &c, the result would be that the carbonate of lime would be 

 slowly carried away in solution by the carbonated water 

 flowing through the cracks and joints of the absorbent rock, 

 and leaving behind the insoluble compact flints and a great 

 part of the earthy matter and iron. To these would be added 

 the clayey and loamy wash from the Tertiary lands, and the 

 remains of beds of that age left in pipes and hollows in the 

 chalk. . . . The clay and flints left by the dissolution of 

 the chalk would be present almost everywhere, whilst the 

 loamy materials that would be formed from the lowest Tertiary 

 beds would most likely be more local. The fact of the clay- 

 with-flints occurring only on the chalk- with-flints is in favour 

 of this view, and it is perhaps owing to the comparatively 



