528 Mr. Archibald Geikie [June 7, 



WEEKLY EVENING MEETING, 



Friday, June 7, 1889. 



Colonel James A. Grant, C.B. C.S.I. F.K.S. Vice-President, in 



the Cbair. 



Archibald Geikie, Esq. LL.D. F.R.S. 



DIRECTOK-GEXERAL OF THE GEOLOGICAL SURVET OF THE UNITED KINGDOM. 



Beceni BesearcJies into the Origin and Age of the Highlands of 

 Scotland and the West of Ireland. 



The records of geological history, like those of the human race, 

 become more fragmentary and illegible, the farther back we trace 

 them into the past. While the younger rocks of the earth's crust have 

 been made to yield a more or less connected story of geographical 

 and biological evolution, the oldest rocks have till comparatively 

 lately been neglected, or have been tacitly left to mere speculation 

 and conjecture. Only within the last few years have these ancient 

 formations been seriously and sedulously attacked by scientific 

 methods of inquiry. Though the progress of investigation has 

 necessarily been slow, a steady advance in knowledge can be 

 chronicled. There is a curious fascination in this dei)artment of 

 geology. These venerable rocks reveal to us the oldest known part 

 of the outer shell of our planet. The palimpsest of the earth's 

 surface has been written over again and again during the long ages 

 of geological history ; but down among these bottom-rocks we reach 

 the earliest recognisable inscriptions, and come as near towards the 

 beginning of things as geological evidence by itself is ever likely to 

 lead us. These records carry us back to a time anterior to that of 

 the oldest fossiliferous formations, possibly to an ej)Och that pre- 

 ceded the appearance of vegetable or animal life on the globe. They 

 reveal to us the very foundations of the earth's crust, on which all 

 other known rocks rest, and out of the waste of which the greater 

 part of these rocks has been formed. 



Within the last ten years, after prolonged misconception and 

 neglect, the most ancient rocks of the British Isles have come to 

 occupy a foremost place among the researches of the geologists of 

 this country. The tracts where they are now exposed to view, often 

 among the wildest mountains, or " placed far amid the melancholy 

 main," have become favourite geological hunting grounds, and have 

 furnished a notable amount of material for those disputes and com- 

 bats which seem to form a necessary element in geological progress. 

 Avoiding, as far as possible, matters of controversy, I propose this 

 evening to offer a brief outline of the actual state of knowledge, up 

 to the present time, of the history of those ancient crystalline masses 



