Geological Society. 313 



the Paris Academy of Sciences), have been approved and acted 

 upon by competent judges, is shown by the fact that the charge of 

 preserving from further electric injury the grandest architectural 

 monument of Belgium has been intrusted to his care. 



We recommend Professor Melsens's work to the careful perusal 

 of all w 7 ho are interested in the preservation from injury by light- 

 ning of ships and buildings, as well for its useful mechanical sug- 

 gestions as for its interesting and accurate scientific details. 



XLIY. Proceedings of Learned Societies. 



GEOLOGICAL SOCIETY. 



[Continued from p. 237.] 



January 23, 1878.— Prof. P. Martin Duncan, M.B., F.R.S., 



President, in the Chair. 



THE following communication was read : — 

 1. " On the Secondary Eocks of Scotland. — Part III. The Strata 

 of the Western Coast and Islands.''" By John W. Judd, Esq., E.R.S., 

 F.G.S., Professor of Geology in the Royal School of Mines. 



The existence of scattered patches of fossiliferous strata lying be- 

 tween the old gneissic rocks and the masses of Tertiary lava in the 

 Hebrides, has been known to geologists for more than a century. 

 By Dr. Macculloch, who did so much for the elucidation of the in- 

 teresting district in which they occur, these strata were referred to 

 the Lias ; but Sir Roderick Murchison showed that several members 

 of the Oolitic series were also represented among them. Later 

 researches have added much to our knowledge of the more accessible 

 of these isolated patches of Jurassic rocks in the Western Highlands. 



During the seven years in which he has been engaged in the study 

 of these interesting deposits, the author of the present memoir has 

 been able to prove that not only is the Jurassic system very 

 completely represented in the Western Highlands, but associated 

 with it are other deposits representing the Carboniferous, Poikilitic 

 (Permian and Trias), and Cretaceous deposits, the existence of which 

 in this area had not hitherto been suspected ; and by piecing to- 

 gether all the fragments of evidence, he is enabled to show that 

 they belong to a great series of formations, of which the total 

 maximum thickness could have been little, if any thing, short of a mile. 



The relations of the scattered patches of Mesozoic strata to the 

 older and newer formations respectively, are of the most interesting 

 and often startling character. Sometimes the secondary rocks are 

 found to have been let down by faults, which have placed them 

 thousands of feet below their original situations, in the midst of 

 more ancient masses of much harder character. More usually they 

 are found to be buried under many hundreds, or even thousands of 

 feet of Tertiary lavas, or are seen to have been caught up and en- 

 closed between great intrusive rock-masses belonging to the same 

 period as the superincumbent volcanic rocks. ' Occasionally the only 

 evidence which can be obtained concerning them is derived from 

 fragments originally torn from the sides of Tertiary volcanic vents, 

 and now found buried in the ruined cinder cones which mark the 



