[ iv ] 
XI. Further Researches on the Polarity of the Diamagnetic Force. By John Tyndall, 
Esq., F.R.S., Membre de la Socidtd Hollandaise des Sciences ; Foreign Member 
of the Physical Society of Berlin, and Professor of Natural Philosophy in the 
Royal Institution page 237 
XII. On Axes of Elasticity and Crystalline Forms. By William John Macquorn 
Esq., C.E., F.R.SS. Lond. and Edin 261 
XIII. Introductory Research on the Induction of Magnetism by Electrical Currents. 
By J. P. Joule, Esq., F.R.S., Corr. Mem. R.A., Twin, Hon. Mem. of the 
Philosophical Society, Cambridge, S^c 287 
XIV. Account of Pendulum Experiments undertaken in the Horton Colliery, for the- 
purpose of determining the Mean Density of the Earth. By G. B. Airy, Esq., 
F.R.S., Astronomer Royal 297 
Supplement to the “ Account of Pendulum Experiments undertaken in the Horton 
Colliery T'' being an Account of Experiments undertaken to determine the Cor- 
rection for the Temperature of the Pendulum. By G. B. Airy, Esq., F.R.S., 
Astronomer Royal 343 
XV. On Periodical Laws discoverable in the Mean Effects of the larger Magnetic 
Disturbances . — No. III. By Colonel Edward Sabine, R.A., D.C.L., Treas. 
and H.P.R.S. 357 
XVI. On the ultimate arrangement of the Biliary Ducts, and on some other points in 
the Anatomy of the Liver of Vertebrate Animals. By Lionel S. Beale, M.B., 
Professor of Physiology in Kings College, London ; Physician to Kings Col- 
lege Hospital. Communicated by F. Kiernan, Esq., F.R.S 375 
XVII. On the Enumeration of yi-edra having Triedral Summits, and an {yi—\)-gonal 
Base. By the Rev. Thomas P. Kirkman, M.A. Communicated by A. Cayley, 
Esq., F.R.S 399 
XVIII. On the Representation of Poly edr a. By the Rev. Thomas P. Kirkman, M.A. 
Communicated by A. Cayley, Esq., F.R.S 413 
XIX. On the Structure, Functions, and Homologies of the Manducatory Organs in 
the Class Rotifera. By Philip Henry Gosse, Esq. Communicated by 
Thomas Bell, Esq., V.P.R.S., Pres. L.S ...419 
XX. Researches on the Action of Sulphuric Acid upon the Amides and Nitriles, 
together with Remarks upon the Conjugate Sulpho-acids. By George B. Buck- 
ton, Esq., F.L.S., F.C.S., and A. W. Hofmann, LL.D.,Ph.D., F.R.S. 8^c. 453 
XXI. Elements of a Mathematical Theory of Elasticity. By Professor William 
Thomson, M.A., F.R.S 481 
