XXVIII THE ROYAL SOCIETY OF CANADA 



7. — On the Helium Content of the Natural Gases of Canada. 

 By Professor J. C. McLennan, O.B.E., F.R.S., and Professors E. F. 

 Burton, John Satterly and H. F. Dawes. 



8. — On the Use of a Jamin Interferometer for Estimations of 

 Helium when mixed with Air. By Professor J. C. McLennan, O.B.E., 

 F.R.S. and R. T: Elworthy, B.Sc. 



9. — On a Continuous Flow Method of Purifying Helium by the 

 Use of Charcoal. By R. T. Elworthy, B.Sc, and Evan Edwards, 

 M.A. 



10. — On the Estimation of the Helium Content of Mixtures of 

 Gases by the Use of a Katharometer. By V. F. Murray, M.A., B.Sc. 



IL — On Permeability of Balloon Fabrics for Hydrogen or Helium. 

 By V. F. Murray, M.A., B.Sc, and R. T. Elworthy, B.Sc 



12. — Composition of Vapour and Liquid Phases of Mixtures of 

 Nitrogen and Methane. By H. A. McTaggart, M.A., and Evan 

 Edwards, M.A. 



13. — On the Optical Transparency of Certain Samples of Fluorite. 

 By J. F. T. Young, M.A., and H. J. C. Ireton, M.A. 



14.- — Experiments on Acoustic Depth Sounding carried out in 

 the Gulf of St. Lawrence, September, 1915. By Louis V. King, D.Sc, 

 F.R.S.C. 



15.— On the Theory and Design of Electrically Operated Aerial 

 and Submarine Sound Generators and Receivers. By Louis V. King, 

 D.Sc, F.R.S.C, McGill University. 



16. — On the Design of Continuously Tunable Diaphragms. By 

 Louis Vessot King, D.Sc, F.R.S.C, McGill University. 



17. — Measurements of Temperature Gradients in Air Contained 

 between Parallel Planes Maintained at Different Temperatures. By 

 G. H. Henderson, M.A. 



18. — ^The Variation of the Coefficient of Viscosity of Gases with 

 Temperature. By Robert Clark. 



19. — ^The Velocity of Sound and the Ratio of the Specific Heats. 

 By T. C Hebb. 



20. — A New Method for the Determination of the Size of the 

 Colloidal Particles. By Professor E. F. Burton, F.R.S.C 



21. — The Absorption of Gases by Carbonized Lignite. By 

 Stewart McLean, M.A. 



22. — Determination of the Density of Absorbing Substances. By 

 Stewart McLean, M.A. 



23.— Light Absorption by Crude Rubber. By R. C Dearie, Ph.D. 

 and E. R. L Pratt, B.A. 



