I. 



PJPERS OF THE PHYSICAL CLASS. 



I. Of certain Natural Appearances of the Ground on 

 the Hill of Arthur's Seat. By JJMES HUTTOK, M. D. 

 F. R. S. Edin. and Member of the Royal Academy of Agri- 

 culture fl/ Paris *. 



IN fummer 1776, ProfefTor Ferguson obferved a parti- 

 cular appearance on the hill of Arthur's Seat, near the fum- 

 mit, which drew his attention, and which he could not under- 

 ftand. He then carried Dr Black and me to the place, where 

 we found fomething which, at a diftance, refembled the wi- 

 thered grafs of a foot-path, but which traverfed a fhoulder of 

 the hill, in fuch a diredlion as correfponded to neither Iheep- 

 track nor foot-path. Upon a near infpe(5lion, it appeared to be 

 a narrow ftripe of the grafs quite dead and withered. The 

 breadth of this ftripe was about nine, or, in fome places, twelve 

 inches : the fides of this track were perfedly defined, without 

 any gradation from green to withered grafs, all the plants in 

 the track being killed, without the contiguous part having fuf- 

 fered in the leaft. The length of this track was confiderable, a 

 hundred yards or two, extending from the fouth-eaft fide of 



a 2 the 



* This Paper was read before the Philofophical Society of Edinburgh in June 1778. 

 It is now printed by order of the Committee for publication of the Tranfaftions of the 

 Royal Society of Edinburgh. 



