VI CONTENTS. 



Dr Knox on the structure of the Ribs, . , . .26 



On the Composition of some Iron Slags, By J. F. W. Johnston, 

 Esq., F.R.S.E., ....... 26 



On a New Species of Coloured Fringes developed between certain 

 pieces of Plate Glass, exhibiting a new variety of Polarization, and 

 a peculiar property which renders them available for the purpose 

 of Micrometry. By Mungo Ponton, Esq., . . .31 



Communication relative to the Fresh Water Limestone of Burdie- 

 house, near Edinburgh, belonging to the Carboniferous Group of 

 Rocks. By Dr Hibbert, F.R.S.E., . . . .33 



A General View of the Phenomena displayed in the neighbourhood 

 of Edinburgh, by the Igneous Rocks, in their relations with the 

 Secondary Strata ; with reference to a more particular descrip- 

 tion of the section which has been lately exposed to view on the 

 south side of the Castlehill. By the Right Honourable Lord 

 Greenock, ....... 35 



Researches on the Vibrations of Pendulums in Fluid Mediums. By 

 George Green, Esq. Communicated by Sir G. Ffrench Brom- 

 head, Bart., ....... 36 



Observations on the Fossil Fishes lately found in Orkney. By 

 Thomas Stewart Traill, M.D., F.R.S.E, ... 37 



Notice of further discoveries at Burdiehouse. By Dr Hibbert, 38 



On the Investigation of Magnetic Intensity, by the Oscillations of a 

 Horizontal Needle. By William Snow Harris, Esq., F.R.S., 39 



Experiments on Magnetic Intensity made at Liverpool and Man- 

 chester. By Thomas Stewart Traill, M.D., F.R.S.E., . 40 



Description and Analysis of a Mineral from Faroe, not before ex- 

 amined. By Arthur Connell, Esq., . . . .41 



Short Notice relative to the position of the Limestone at Burdie- 

 house, and the relation it bears to the Mountain Limestone of 

 Muirhouse. By Dr Hibbert, ..... 42 



On the Principle of Vital Attraction and Repulsion, with some ap- 

 plications to Physiology and Pathology. By W. P. Ahson, M.D., 

 F.R.S.E., 44 



Notice of some recent discoveries in Organic Chemistry. By Wil- 

 liam Gregory, M.D., F.R.S.E., . . . .47 



On the Structure, Position, and other particulars of a Fossil Tree, 

 found in Craigleith Quarry in the month of October last. By 

 H. T. Maire Witham, Esq., ..... 47 



Analysis of Coprolites from the Limestone of Burdiehouse. By 

 Arthur Connell, Esq., ...... 48 



Notice relative to the Polyzonal Lenses belonging to the Commis- 

 sioners of the Northern Lighthouses. By Alan Stevenson, Esq., 49 



Additional Notice relative to the Freshwater Limestone in the 

 vicinity of Edinburgh, belonging to the Carboniferous Group of 

 Rocks. By Dr Hibbert, ..... 50 



On the Force of the Latin Prefix ve or vae. By the Rev. John Wil- 

 liams, ........ 54 



On a new Register Anemoscope. By Dr Traill, . . 54 



