SECTIONAL TRANSACTIONS .—H. 423 
Mr. A. LEsLIE ARMSTRONG.—Evolution of flint mining at Grime’s Graves, 
Norfolk (12.0). 
Aided by a grant from the trustees of the Percy Sladen Memorial Trust, 
a scheme of systematic research was instituted at Grime’s Graves in 1921, 
and has been carried on progressively since that date. 
Trenching and trial excavations have defined the area within which 
flint mining was carried on and also revealed the circumstances which 
caused the mining to be confined within these limits. The flint mines 
have been fully excavated and a further mine shaft is now in progress. 
These excavations demonstrate a gradual evolution both in mining methods, 
in the tools used, and in the form of the mine shafts. ‘Three well-defined 
phases are recognisable, viz. : 
(1) Primitive phase -——Shafts, devoid of galleries, in which picks made 
from the long bones of animals are used exclusively. 
(2) Intermediate phase —Shafts in the form of open workings, but devoid 
of galleries, in which deer antler picks first appear. In the earlier examples 
bone picks predominate. In those of the later phase deer antler picks 
exceed the bone picks in number. 
(3) Late phase—Deep shafts with mined galleries; celts with pointed 
butts. Deer antler picks. 
The probable period of commencement and cessation of mining is 
discussed and evidence advanced of occupation in Bronze-Iron Age times, 
prior to which all mining had ceased. 
AFTERNOON. 
Excursion to Caistor Camp, Woodhenge, Armingham, Whitlingham 
(2.30)... 
Saturday, September 7. 
Excursion to Grime’s Graves, Brandon, Thetford (9.30). 
Sunday, September 8. 
AFTERNOON. 
Excursion to Monastic Buildings of Norfolk and North Norfolk 
Coast Sections (2.0). 
Monday, September 9. 
PRESIDENTIAL AppREss by Sir A. SmirH Woopwarp, F.R.S., on Recent 
progress in the study of early man (10.0). (See p. 129.) 
Mr. O. Davirs and Mr. E. E. Evans.—Horned cairns in Ulster (11.0). 
This paper deals with some results of a series of excavations conducted 
under the auspices of the Belfast Municipal Museum, the Belfast Natural 
History and Philosophical Society and the Queen’s University of Belfast, 
during the last four years. They have revealed a vigorous horned-cairn 
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