CONTENTS. 



vn 



PART V. 



N". XL. 

 XLI. 



XLI.* 

 XLir. 

 XLIII. 



XLIV. 



XLV. 



XLVI. 



XLVII. 



XLVIII. 



XLIX. 



L. 



LI. 



LI I. 



On the Critical Values of the Sums of Periodic Series : by G. G. Stokes, 

 M.A., Fellow of Pembroke College, Cambridge 533 



A Mathematical Theory of Luminous Vibrations: by the Rev. J. Challis, 

 M.A., F.R.A.S., Plumian Professor of Astronomy and Experimental Phi- 

 losophy in the University of Cambridge 5S-i 



Supplement to a Paper "On the Intensity of Light in the neighbourhood of a 

 Caustic:" by George Biddei,!, Airy, Esq., Astronomer Royal 595 



Some Remarks on the Theory of Matter: by Robert L. Ellis, M.A., 

 Fellow of Trinity College, Cambridge 600 



Methods of Integrating Partial Differential Equations: by Augustus De 

 Morgan, of Trinity College, Cambridge, Secretary of the Royal Astrono- 

 mical Society, and Professor of Mathematics in University College, London. 606 



Second Memoir on the Fundamental Antithesis of Philosophy : by VV. 

 Whbwell, D.D., Master of Trinity College, and Professor of Moral 

 Philosophy 6I4, 



Observations of the Aurora Borealis of November 17, 1848, made at the 

 Cambridge Observatory : by the Rev. J. Challis, M.A., F.R.S., F.R.A.S., 

 Plumian Professor of Astronomy and Experimental Philosophy in the 

 University of Cambridge 621 



On Clock Escapements: by Edmund Beckett Denison, Esq., M.A., of 

 Trinity College, Cambridge 633 



(Supplement.) On Turret-Clock Remontoirs: by E. B. Denison, M.A., 



of Trinity College 630 



On the Formation of the Central Spot of Neniton's Rings beyond the Critical 

 Angle: by G. G. Stokes, M.A., Fellow of Pembroke College 642 



Of the Intrinsic Equation of a Curve, and its Application: by W. Whewell, 

 D.D., Master of Trinity College 650 



On the Variation of Gravity at the Surface of the Earth : by G. G. Stokes, 

 M.A., Fellow of Pembroke College 672 



On Hegel's Criticism of Newton's Principia : by W. Whewell, D.D., 

 Master of Trinity College 606 



Discussion of a Differential Equation relali?ig to the breaking of Railway 

 Bridges: by G. G. Stokes, M.A., Fellow of Pembroke College 707 



