iv 



CONTENTS. 



when revolving at a high velocity, as when in a ^tate of quiescence. 

 20. Mr Baily on the Aberdeen Standard Scale of 3 feet. 21. Mr S. 

 Harris on Thermometric Observations. 22. Mr G. Jerrard on the so- 

 lution of Algebraic Equations. 23. Mr Phillips on the Fall of Rain. 

 24. Colonel Sykes on Measuring Heights by the Thermometer. 25. 

 Mr M'Cullagh on Reflection and Refraction of Polarized Light at 

 the surfaces of Crystals. 26. Mr M'Gauley on Magnetism. 27. Pro- 

 fessor Apjohn on the Dew Point. 28. Professor Hamilton on Mr Challis's 

 results respecting the simultaneous vibrations of a Cylindrical Tube, and 

 the Column of Air contained in it. 29. Professor Wheatstone on Speak- 

 ing Machines. 30. Mr Whewell on a new Anemometer. 31. Profes- 

 sor Lloyd's Magnetic Observations. 32. Mr Hamilton on the theory of 

 Varying Orbits. 33. Mr Kane on the Interference of Sound. 

 Mechanical Science applied to the Arts, 368. — 1. Mr Hodgkinson on 

 the Collision of Beams and Piles. 2. Mr Mallet on the Fracture of Bars 

 of Cast Iron. 3. Mr Ettrick on a new Compass. 4. Mr Pritchard on an 

 Achromatic Microscope. 5. Mr Russell on the Solids of least resistance, 

 in reference to Steam-Vessels. 6. Mr John Taylor on the quantity of 

 Coal required for Steam-Engines, &c. 7- Dr Lardner on Rail-Roads. 

 8. Mr Ettrick on certain improvements in Steam-Engines, &c. 9. Mr 

 Cheverton on the Sculpture of Busts by Machinery. 10. Mr Grubb on 

 an improved model for mounting an Equatorial Instrument. 11. Lieut. 

 Denham on the Vibratory effects of Rail-Roads. 12. Mr Stevelly on a 

 new Self-Registering Barometer. 



Section B. Geology and Geography, 372 — 1. Mr Griffith on the Geology 

 of Ireland, accompanied with a geologically coloured map, 2. Dr West on 

 the Geography of some parts of Greenland. 3. Archdeacon Verschoyle 

 on a system of Trap-Dikes passing through the counties of Mayo and 

 Sligo. 4. Mr Phillips on Fossil Astacidse. 5. Lieutenant Stotherd on 

 the Granite in the county of Cavan. 6. Mr Griffith on the Unstratified 

 Rocks of Ireland. 7- Professor Phillips on the Geological Distribution 

 of Belemnites. 8. Lieutenant Denham, R. N., remarks on a Map illus- 

 trative of the Estuaries of the Dee and Mersey, 9. Mr Williams on the 

 Fossil Plants collected in the coal districts of Devonshire and Pembroke- 

 shire. 10. M. Agassiz on the general results obtained from the inspec- 

 tion of the greater part of the collections of Fossil Fishes in Great Bri- 

 tain, and his remarks on a Fossil Fish exhibited by Captain Portlock. 

 11. Dr Traill on the Geology of Spain, and Mr Greenough on the con- 

 nexion of the Alps and Pyrenees. 12. Mr Smith on some Fossils found 

 in a quarry near Glasgow. 13. Mr Whewell on various points in Phy- 

 sics connected with Geology. 14. Mr Hartop on the faults in the South- 

 ern Division of the West Riding of Yorkshire. 15. Mr Murchison and 

 Professor Sedgwick on the Older Rocks of England and Wales. 16. Dr 

 Jacob on Fossil Madrepores. 17- Mr Phillips on a Tertiary Deposit near 

 Burlington, on the north coast of England, 18. Mr Lyell on the Fos- 

 sils of the Crag. 



Section C. Chemistry and Mineralogy, 391. — 1. Mr Davy on the Corro 



