viii CONTENTS. 



PAGE 



XXV. Experiments mi the Ordinary Refraction of Iceland Spar. By Wil- 

 liam Swan, Esq. Communicated by Professor Kelland, 37.) 



XXVI. Ohsenatimis on the Temperature of the Ground at Trevandrum, in 

 India, from May 1842 to December 1845. By John Caldecott, 

 Esq., Astronomer to tlie Rajab of Travancore. Communicated in 

 a Letter to Professor J. D. Forbes, 379 



XXVII. On the Parallel Roads of Lochaber, with Remarks on the Change of 

 Relative Levels of Sea and Land in Scotland, and on the Detrital 

 Deposits in that Country. (WitbaPlate.) By David Milne, Esq., 395 



PART IV. 



XXVIII. Memoir of Br Thomas Charles Hope, late Professor of Chemistry 

 in the University of Edinburgh. By Thomas Stewart Traill, 

 M.D 419 



XXIX. On the Colouring Matter of the Morinda citrifolia. By Thomas 



Anderson, M.D., 435 



XXX. Notice of the Orbit of the Binary Star a Centauri, as recently deter- 

 mined by Captain W. S. Jacob, Bombay Engineers. By Professor 

 C. PiAzzi Smyth, 445 



XXXI. An Attempt to Improve the present Methods of Determining the 

 Strength and Direction of the Wind at Sea. (With a Plate.) By 

 Professor C. PiAZZi Smyth, ....... 455 



XXXII. On the Products of the Destructive Distillation of Animal Substances. 



Part I. By Thomas Anderson, M.D., .... 463 



XXXIII. On the Action of the Dry Gases on Organic Colouring Matter, and its 



relation to the Theory of Bleaching. By George Wilson, M.D., 475 



