CONTEJ^TS. XUl 



Page 



4. On the Use of the Interferometer in the Study of Electric Waves. By G. 



F. Hull 574 



5. An Instrument for Recording Rapidly Varying Potential Differences and 



Currents. By W. Duddell 575 



6. Report on Electrical Standards 575 



7. *0n the Calculation of the Coefficient of JIutual Induction of a Circle and 



a Co-axial Helix. By Professor J. Vieiamtj Jones, F.R.S 575 



8. On a Determination of the Ohm made in Testing the Lorenz Apparatus 

 of the McGill University. By Professor W. E. Ateton, F.R.S., and 

 Professor J. Viriamu Jones, F.R.S 575 



9. On the Relations between Arc Curves and Crater Ratios with. Cored 

 Positive Carbons. By Hertha Ateton 575 



10. On the Source of Luminosity in the Electric Arc. By H. Cee'R' and O. 



H. BAsatriN 577 



11. On some New Forms of Gas Batteries and a New Carbon-consuming 



Battery. By Willard E. Case 579 



1 '2. On the Determination of the State of lonisation in Dilute Aqueous Solu- 

 tions containing- two Electi'olytes. By Professor J. G. SlAcGREeoR, 

 D.Sc 581 



Department II. — General Physics. 



1. An Apparatus for Verifying the Law of Conservation of Energy in the 



Human Body. By Professor W. 0. Atwater and Professor E. B. Rosa 583 



2. The Rate of the Decrease of the Intensity of Shrill Sounds with Time. 



By A. Walmer Duff 583 



3. A New Instrument for Measuring the Intensity of Sound. By A. G. 



AVebstee and B. F. Shaepe 584 



4. Atmosphere in its Effects on Astronomical Research. By Peecival 

 Lowell 585 



5. ^Automatic Operation of Eclipse Instruments. By Professor David P. 

 Todd 585 



G. The Cause of the Semi-annual Inversions of the Type Solar Curve in the 

 Ten-estrial Magnetic Field. By Professor Frank H. Bigelow 585 



7. *Observations at Toronto with Magnet Watch Integrator. By Professor 

 Frank H. Bigelow 586 



8. The Yerkes Observatory. By George E. Hale o86 



0. *The Effects of Tension and Quality of the Metal upon the Changes in 

 Length produced in Iron Wires by Magnetisation. By B. B. Brackett. 586 



10. On the Susceptibility of Diamagnetic and Weakly Magnetic Substances. 



By A. P. AViLLS 586 



11. On Magnetic Periodicity as connected with Solar Physics. By Arthur 

 Harvey 587 



WUBNESDAY, AUGUST 25. 



1, On the Refractivity of certain Mixtures of Gases. By Professor Ramsay, 

 F.R.S., and Morris AV.Travees 587 



i'. Note on the Use of the Trifilar Suspension in Physical Apparatus. By 

 SiLTANua P. Thompson, F.R.S 588 



