CONTENTS 



OF THE 



FOURTH VOLUME. 



PART L 



HIS TORT of the SOCIETT, 



Four Theorems for refolding all the Cafes of Plane and Spheri- 

 cal Triangles, by the Reverend Mv YiQiq,y, - Page 4. 



Dijfertation on the Philofophy of Light , Heat, and Fire, by 

 Dr Hutton, - - - - 7. 



Improvement of the Mercurial Level, by Mr Keith, - 17. 



ExperimeTits on the EffeBs of Opium on the Living Animal^ by 

 Dr Wilfon, - - - - 18. 



On the Diurnal Variations of the Barometer, by Dr Balfour 

 of Calcutta, - - - -^ - 25. 



On the Sulphurating of Metals, by Dr HvLttonj, - 27. 



New Obfervatory at Aberdeen, -■ - 29. 



^ P P E N D IX. 



Office^Bearers of the ^ocizTYi _ _ _ ^r. 



List of Membzks, continued from the third Volume, - ^2* 



Members deceased, - - - 36. 



Donations, _ -. - -. 38. 



I. Biographical Account of Lord AhercYomhy, - (i). 



II. Biographical Account of William Tytler, Efq; of Wood- 



heufelee, ~ -. - (17). 



III. Biogra- 



