TKANSACTIONS OF THE SECTIONS. 



Section A.— MATHEMATICAL AND PHYSICAL SCIENCE. 



THURSDAY, AUGUST 21, 1879. 



Page 



Address by G. Johnstone Stonet, M.A., F.R.S., M.R.I.A 243 



1. Report of the Committee for commenciDg Secular Experiments upon the 

 Elasticity of Wires 248 



2. Report of the Committee for making more Accurate Determinations of the 

 Mechanical Equivalent of Heat , 248 



3. On Etherspheres as a Vera Causa of Natural Philosophy. By Rev. S. 



Earnshaw, M.A 248 



4. On some New Instruments recently constructed for the continuation of 

 researches on Specific Inductive Capacity. By J. E. H. Gordon, B.A., 

 Assistant Secretary of the British Association 249 



5. On Secular Changes in the Specific Inductive Capacity of Glass. By 



J. E. H. Gordon, B.A., Assistant Secretary of the British Association.... 250 



6. On the Cause of Bright Lines in the Spectra of Comets. By G. John- 

 stone Stoney, M.A., F.R.S., M.R.I.A 251 



7. Sur le Maximum d'lntensite 1 du Spectre Photographique Solaire. Par le 

 Dr. J. Janssen, de l'lnstitut de France, Directeur de l'Ohservatoire de 

 Meudon 252 



8. On the Changes of Volume in Iron when passing from the Liquid to the 



Solid State, and on an Instrument for observing the same. By T. 

 Wrightson, Memb. Inst. C.E., F.G.S 253 



9. On the Isophotal Binocular Microscope. By Samuel Holmes 253 



10. Some Observations on Generic Images. By W. Cave Thomas, F.S.S 253 



FRIDAY, AUGUST 22, 1879. 



1. Report of the Committee for Procuring Reports on the Progress of Mathe- 

 matics and Physics 254 



2. Report of the Committee on Underground Temperature 254 



3. Report of the Committee on Atmospheric Electricity at Madeira 254 



4. On the Retardation of Phase of Vibrations transmitted by the Telephone. 



By Professor Silvantjs P. Thompson, B.A., D.Sc 254 



5. The Pseudophone. By Professor Sllvantts P. Thompson, B.A., D.Sc 255 



6. On the Tension of Vapours near Curved Surfaces of their Liquids. By 



G. F. Fitzgerald 255 



