^,j CONTENTS. 



IX. Researches on Heat. Third Series. ^1. On the unequally Polar izahle 

 Nature of different kinds of Heat. ^ 2. On the Depolarization of Heat. 

 J 3. On the Refrangibiliti/ of Heat. By James D. Forbes, Esq., 

 F.R.SS. L. SfEd., Professor of Natural Philosophy in the University of 

 Edinburgh, . . . . . . . . . . .176 



X. On the Real Nature of Symbolical Algebra. By D. F. Geegory, B A., 



Trin. Coll. Cambridge, 208 



XL Investigation of a New Series for the Computation of Logarithms ; with a 

 New Investigation of a Series for the Rectification of the Circle. By 

 James Thomson, LL.D., Professor of Mathematics in the University 

 of Glasgow, . . . . . 217 



XII. Of the Third Pair of Nerves, being the first of a series of Papers in ex- 

 planation of the diff'erence in the origins of the Nerves of the Encephalon, 

 as compared with those which arise from the Spinal Marrotv. By Sir 

 Charles Bell, K.H, F.R.SS. L. SfEd., M.D.II.Gott., 6fc. . .224 



XIII. Of the Origin and Compound Functions of the Facial Nerve, or Portio 



dura of the Seventh Nerve ; — being the Second Paper in explanation of 

 the difference between the Nerves of the Encephalon, as contrasted uith 

 the regular Series of Spinal Nerves. By Sir Charles Bell, K.H., 

 F.R.SS. L. S,- E., M.D.H.Gott., Sfc 229 



XIV. Of the Fourth and Sixth Nerves of the Brain ; — being the concluding 



paper on the distinctions of the Nerves of the Encephalon and Spinal 

 Marrow. BySlr Charles Bell, K.H.,F.R.SS.L.i)Ed.,M.B.H.Gott., 

 S^c 237 



XT. Inquiry whether Sea- Water has its Maximum Density a few Degrees 

 above its Freezing Point, as Pure Water has. By Thomas Charles 

 Hope, M.D., V.P. R.S.Ed., F.R.S., Professor of C/iemistry in the Uni- 

 versity of Edinburgh, 242 



XVI. On the Mid-Lothian and East-Lothian Coal-Fields. By David Milne, 



Esq., F.R.S.Ed., F.G.S. 253 



