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Down and Dundas; at the foitner place the quarries of Great 

 Oolite were visited, and a discussion as to the origin of the " head" 

 - — a technical name for the oolitic debris which caps all the 

 quarries to a depth of 6 or 8 feet — took place. One opinion 

 advanced by the Seci'etary was that it was the result of the 

 grinding and crushing of field ice which covered our hills at the 

 glacial period, the depth of the head depending upon the 

 amount of power existing at the time. Another view put forth 

 was that of Mr. Mitchell, who considered that the cause was to be 

 Bought for in the percolation of rain and surface water, succeeded 

 by frost, the nearly horizontal line, which in Mr. Mitchell's opinion 

 generally separated the debris from the more solid beds beneath, 

 being due to a parting of clay which prevented the percolation of 

 water and subsequent disintegration by frost beneath this line. 

 From Combe Down the members crossed over the hill and the 

 canal to Dundas quarry, where the Upjjer Lias is capped by the 

 sands of the Inferior Oolite. Thence up the hill by Conkwell, and 

 through the Warley woods to Farley Down, examining the 

 escarpment of Oolite on the way. The diagonal jointing of the 

 beds between an upper and lower horizontal stratum unaffected by 

 those joints formed another topic for discussion ; Mr. Mitchell 

 thinking that these peculiar features were due to current action as 

 the beds thin out towards the valley (this latter view nf the beds 

 thinning out towards the valley being however an assumption not 

 proved satisfactorily as yet). 



On 15th of March the Club visited the peculiar steps or "lynchets" 

 at the head of Chilcombe valley, supposed to have been ancient 

 lines of fortification ; but most probably due to the wearing away 

 by meteoric agency of the softer poi-tious of the strata intervening 

 between the harder beds, and leaving these latter exposed in ridges, 

 the action of the plough and artificial cultivation, tending also to 

 carve these terraces out more distinctly (vide Geological Magazine, 

 vol. III., p. 293). Walking thence over Charmy Down, the 

 Gloucester Road was reached, and the site of the landslip inspected. 

 The Secretary and some other members retunaed over Solsbury 

 Hill, and found some well formed flint flakes, and on another occa- 

 sion a well shaped javelin point or arrow head of reddish chert. 



