354 SECTIONAL TRANSACTIONS. — B, C. 



7, Report of Committee on Fuel Economy (Prof. W. A. 



Bone, P.E.S.), and Discussion thereon. See p. 248. 



Friday, August 27. 



8, Dr- J- S. Owens. — Researches on Atrjiosplieric Pollution 



and its Measurement. 



9, Prof. F. M. Jaeger. — Research Work at High Tempera- 



tures, and the Determination of Surface Tension and 

 Electrical Conductivity between -100° and +1650° C. 



The following excursions were arranged for members of the 

 Section : Melingriffith Tinplate Co. ; South Wales Indiarubber 

 Co.; Cardiff Gas Co.; Cardiff Dowlais Works; exhibits, etc., in 

 Chemical Lfaboratories, Mental Hospital, Eadyr; Powell Duffryn 

 Co. ; Tharsis Sulphur and Copper Co. 



SECTION C— GEOLOGY. 



(For references to the publication elsewhere of communications entered in 

 the following list of transactions, see p. 380.) 



Tuesday, August 24. 



1. Presidential Address by Dr. F. A. Bather, F.E.S. 



See p. 61. 



2. Prof. A. Hubert Cox. — Address on the Geology of the 



Cardiff District. 

 3 Dr. J. W. Evans, F.B.S.—The Origin of the Alkali 



Igneous Rocks. 



These rocks, distinguished by unusually high proportion 

 of alkalies, relatively to alumina, and lime, occur mainly 

 where the crust of the earth is thick, the heat-gradient low, 

 and there has been no folding since remote times. ]\Iagmas 

 appear to have reached the suiface by fault fissures from great 

 depths where high pressures are associated with compara- 

 tively low temperatures. Ciystallisation proceeding under 

 such circumstances, there would be an early formation of 

 minerals with small molecular volumes, garnets, kyanite, 

 epidote, and zoisite, minerals rich in lime and alumina. 

 Zoisite may be regarded as the high-pressure representative of 

 anorthite, but there is no corresponding representative of 

 albite or orthoclase. Consequently we should expect a 

 residual magma exceptionally rich in alkalies which would 

 furnish the material necessary for formation of alkali rocks. 



4. Reports of Research Committees. See p. 261. 



Wednesday, August 25. 



5. Joint Meeting with Seotions D and K. Discussion.— 



Mendelisin and Paleontology: The Factorial Inter- 

 pretation of Gradual Changes, especially when New 

 Characters appear late in the Individual Life-cycle. 



