CONTENTS. Vii 



Notice of recent Measures of the Ring of Saturn. By Professor C. 

 Piazzi Smyth, ...... 192 



Chemical Notices. By Professor Gregory, . . .193 



Observations on the Structural Character of Rocks. Part II. By 

 Dr Fleming, . . . . . .197 



Some Observations on Fish, in relation to Diet. By Dr John 

 Davy, ....... 197 



Remarks on the Torbanehill Mineral. By Dr Traill, . .199 



Notice of the Blind Animals which inhabit the Mammoth Cave of 

 Kentucky. By James Wilson, Esq., . . . 200 



Additional observations on the Diatomaceous Earth of Mull, with 

 a notice of several New Species occurring in it, and Remarks on 

 the value of Generic and Specific Characters in the Classification 

 of the Diatomaceae. By William Gregory, M.D., Professor of 

 Chemistry, ...... 204 



On the Physical appearance of the Comet 3, of 1853. By Professor 

 C. Piazzi Smyth, . . . . . .207 



On the supposed Sea-Snake cast on shore in the Orkneys in 1808, 

 and the Animal seen from H.M.S. Daedalus in 1848. By Dr 

 Traill, ....... 208 



Further Researches on the Crystalline Constituents of Opium. By 

 Dr Thomas Anderson, ..... 215 



What is Coal? By Dr Fleming, . . . .216 



Observations on the Structure of the Torbanehill Mineral, as com- 

 pared with various kinds of Coal. By Professor Bennett, . 217 



Account of the Proceedings of the Conference held at Brussels in 

 August and September 1856, for establishing a uniform system of 

 Meteorological Observations in the Vessels of all Nations, and of 

 the arrangements proposed to be made for conducting the results 

 of the Observations taken on Land with those taken at Sea. By 

 Captain H. James, R.E., F.R.S., &c. Communicated by James 

 Wilson, Esq., . . . . . .218 



On certain Vegetable Organisms found in Coal from Fordel. By 

 Professor Balfour, . . . . .218 



On the Impregnation of the Ova of the Salmonidae. By John Davy, 

 M.D., F.R.SS. Lend. & Edin., Inspector-General of Army Hos- 

 pitals, ....... 219 



Account of a remarkable Meteor seen on 30th September 1853. By 

 William Swan, Esq., ..... 220 



On the Mechanical Action of Heat. By W. J. Macquom Rankine, 

 C.E., F.R.SS.Lond. & Edin., . . . .223 



On the Total Invisibility of Red to certain Colour-Blind Eyes. 

 By Dr George Wilson, ..... 226 



On the Romaic Ballads. By Professor Blackie, . . 227 



On a New Hygrometer, or Dew-Point Instrument. By Professor 

 Connell, ....... 228 



On the Stability of the Instruments of the Royal Observatory. By 

 Professor C. Piazzi Smyth, . . . .229 



On a General Method of effecting the substitution of Iodine for Hy- 

 drogen in Organic Compounds, and on the properties of lodo- 



