XXII. On Staffa, 



By J. Mac Cullocii, M.D. F.L.S. Chemist to the Ordnance, and Lecturer 



on Chemistry at the Royal Military Academy at Woolwich. 



V. Pr. Geol. Soc. 



iF the "Description and Natural History" ofStafFa, by Faujas 

 de St. Fond, or the various other descriptions which have been 

 published of this island by naturalists and by tourists, had exhausted 

 the subject, I should have forborn to have troubled the Society with 

 any remarks on a place which ought now to be well known. 



But a visit to this celebrated island having given me an oppor- 

 tunity of remarking a circumstance before unnoticed, and of some 

 importance in its natural history, I think it my duty to lay it before 

 the Society. In so doing, I find it difficult to avoid entering rather 

 minutely into the general description of the island, particularly since 

 a second examination, besides confirming the remarkable fact I at first 

 noticed, has enabled me to Investigate Its structure more completely. 

 I shall doubtless still leave something to be corrected by those who 

 may come after me. A multiplicity of objects pressing at once for 

 regard, a visit always necessarily hurried from the impossibility of 

 remaining long on the island, a boisterous sea, and a stormy atmos- 

 phere, are hostile to that accuracy of observation which may pre- 

 clude future corrections. 



The circumference of Staffa Is estimated at about two miles. It 

 forms a sort of table land of an irregular surface, bounded on ail 



