IV 



CONTENTS. 



N". XV. 

 XVI. 



XVII. 



XVIII. 

 XIX. 

 XX. 



XXI. 



XXII. 

 XXIII. 



XXIV. 



Part III. 



PAGE 



On Spurious Rainbows: by W. H. Miller, M.A., F.R.S., Professor of 

 Mineralogy in the University of Cambridge 277 



On the Foundation of Algebra, No. II.: by Augustus De Morgan, F.R.A.S., 

 F.C.P.S., of Trinity College ; Professor of Mathematics in University Col- 

 lege, London 287 



An Enquiry into the Causes which led to the Fatal Accident on the Brighton 

 Railway (Oct. 2, 1841), in which is developed A Principle of Motion of 

 the greatest importance in guarding against the Disastrous Effects of Col- 

 lision under whatever circumstances it may occur : by the Rev. J. Power, 

 M.A., Fellow and Tutor of Trinity Hall, Cambridge 301 



Discussion of the Question : — Are Cause and Effect successive or simultaneous ? 

 by the Rev. William Whewell, B.D., Master of Trinity College, and 

 Professor of Moral Philosophy 319 



On the Motion of a small Sphere acted upon by the Vibrations of an Elastic 

 Medium : by the Rev. James Challis, M.A., Plumian Professor of Astro- 

 nomy in the University of Cambridge 333 



Description of an Extinct Lacertian Reptile, Rhynchosaurus artieeps, Owen, 

 of which the Bones and Foot-prints characterize the Upper New Red 

 Sandstone at Grinsill, near Shrewsbury: by Richard Owen, F.R.S., G.S. 

 fyc, Hunterian Professor in the Royal College of Surgeons 355 



A general Investigation of the Differential Equations applicable to the Motion 

 qf Fluids : by the Rev. James Challis, M.A., Plumian Professor of 

 Astronomy and Experimental Philosophy in the University qf Cambridge .. . 371 



On the Propagation qf Luminous Waves in the Interior qf Transparent Bodies : 

 by the Rev. M. O'Brien, M.A., late Fellow of Caius College, Cambridge 397 



On the Steady Motion qf Incompressible Fluids : by G. G. Stokes, B.A., 

 Fellow of Pembroke College 439 



On the Truth qf the Hydrodynamical Theorem, that if udx + vdy + wdz 

 be a Complete Differential with respect to x, y, z, at any one instant, it 

 is always so: by the Rev. J. Power, M.A., Fellow and Tutor qf Trinity 

 Hall 455 



ADVERTISEMENT. 



The Society as a body is not to be considered responsible for any 

 facts and opinions advanced in the several Papers, which must rest 

 entirely on the credit qf their respective Authors. 



The Society takes this opportunity of expressing its grateful 

 acknowledgements to the Syndics of the University Press, for their 

 liberality in taking upon themselves a portion of the expense of printing 

 this Part of its Transactions. 



