SECTIONAL TRANSACTIONS.— G,H. 395 



Variations of hardness are shown by varying dimensions (depth and 

 width) of the groove. The depth can be autographically recorded on a 

 drum covered with photographic paper. Alternatively, the groove is 

 ' scanned ' by optically projecting it at a high magnification and measuring 

 its width at intervals corresponding with a time scale mounted alongside. 

 The width is readily converted into Brinell hardness. 



The continuous hardness test is used to investigate periodic fluctuations 

 of hardness following magnetic or thermal disturbance of the metal, and 

 for recording age-hardening effects. 



The periodic fluctuations are attributed to electromagnetic pulsations in 

 the atomic structure of the metal. 



Afternoon. 



Visit to Messrs. Rolls-Royce, Ltd., works, Derby, and to Messrs. 

 Birkin & Co. 



Wednesday, September 8. 



Dr. L. G. A. Sims. — Specification of the A.C. method in permeability 

 measurement (10. o). 



The paper first records the formation of a B.S.I. Committee to standardise 

 measurements of incremental magnetic quantities, particularly incremental 

 permeability. This step is a direct outcome of the support given by the 

 British Association to the writer's papers at Norwich in 1935 and at Black- 

 pool in 1936, and to the co-operation of the British Standards Institution. 

 The paper then provides a brief outline of the new committee's work to date, 

 but its main purpose is to direct attention to certain difficult matters with 

 which the committee will have to deal in the future. Amongst these are 

 the following : First the definition of a distortion factor, which raises the 

 question of the suitability of form factor as a criterion of wave purity, 

 various alternatives being proposed. Secondly it is pointed out that 

 appropriate nomenclature together with a scheme of symbols urgently 

 require consideration. Thirdly the graphical form in which results may 

 best be presented to industry is discussed. The first two of these, at least, 

 are of international interest and importance and examples are given in the 

 paper of lines along which solutions may be reached. 



Mr. Jas. Greig and Mr. J. E. Parton. — Flux distortion in iron testing. 



SECTION H.-ANTHROPOLOGY. 



Thursday, September 2. 



Mr. A. L. Armstrong. — Palaolithic man in Nottinghatnshire (lo.o). 



Disregarding various Eoliths found in the terrace gravels of the Trent 

 Valley, the earliest definite evidence of man's presence in the county is pro- 

 vided by artifacts of late Acheulian type contained in the gravel of the 

 second terrace of the Trent in the neighbourhood of Beeston, to which 

 attention was first called in 1928. Abundant evidence of occupation during 

 Mousterian times has been provided by the Creswell cave excavations ; also 



