X CONTENTS. 



Page 



4. On Solvable Irreducible Equations of Prime Degree. By Professor George 

 Paxton Young 646 



5. The Tactinvariant of a Conical Section and a Cubic Curve. By Professor 



F. Lindemann, Ph.D 647 



6. On the ' Analysis Situs ' of Threedimensional Spaces. By Professor 



Waxthee Dtce, Ph.D 648 



7. On the Expression of the Co-ordinate of a Point in terms of the Potential 

 and Line of Force at the Point. By Professor W. M. Hicks, M.A 649 



8. On the Pressure at a Point inside a Vortex-ring of Uniform Vorticity. By 



Professor W. M. Hicks, M.A 649 



9. Transformation of the Stereographic Equatorial Projection of a sphere by 



means of a certain form of the Peaucellier Cell. By Professor A. W. 

 Phillips 649 



10. A Geometrical Theorem in connection with the Three-cusped Hypocycloid. 



By R. F. Davis 649 



11. On the Discriminating Condition of Maxima and Minima in the Calculus 



of Variations. By E. P. Culverwell, M.A 649 



12. On the Invariable Plane of the Solar System. By David P. Todd, M.A. 651 



Subsection of Physics. 



1. Report of the Committee for facilitating the adoption of the Metric 



System of Weights and Measures in Great Britain 651 



2. On the Colours of Thin Plates. By Professor Lord Ratleigh, LL.D., 

 F.R.S : 651 



3. On Clark's Standard Cells. By Professor Lord Ratleigh, LL.D., F.R.S. 651 



4. On an Analogy between Heat and Electricity. Bv Professor G. F. Fitz- 



gerald, F.R.S 652 



5. The Telemeter System. By J. Urquhart Mackenzie 652 



6. The Influence of an Electric Current on the Thinning of a Liquid Film. 



By Professors A. W. Reinold and A. W. Rucker 652 



7. On the Diffusion of Metals. By Professor W. Chandler Roberts, F.R.S. 653 



8. On some Phenomena connected with Iron and other Metals in the solid 

 and molten states, with notes of experiments. By W. J.Millar 653 



9. On the Velocity of Light of Different Colours. By Professor George 



Forbes ". 653 



10. On the Velocity of Light in Carbon Disulphide and the Difference in 



Velocity of Red and Blue Light in the same. By Albert A. Michelson 654 



11. On a Systematic Research for Stars with a Measurable Annual Parallax, 



and its Results. By Professor Robert S. Ball, LL.D., F.R.S 654 



12. On an Electrodynamorneter, with extremely light moving coil, for the 



measurement of small alternating currents. By Dr. W. H. Stone 654 



13. On the Law regulating the Connection between Current and Intensity of 



Incandescence of Carbon Filaments in Glow Lamps. By W. H. Preece, 

 F.R.S 654 



14. On the Equations of Dynamo-Electric Machines. By Professor Silvanus 



P. Thompson 655 



15. On Earth Currents. By E. 0. Walker 655 



16. Description of a Cylindrical Slide Rule or Calculating Apparatus. By 

 Edwin Thacher 656 



