affects of Electromagnetism 107 



<irove him down by falling deeper and deeper. The upper 

 part of that mountain, above 20,000 feet, is a great outburst 

 of granite which " protrudes in veins at 12,000 feet, and 

 above this carries up the mica-schist and gneiss in enormous 

 masses to 18,000 and even 20,000 feet, baked and distorted 

 in the most extraordinary manner." 



Afterwards Mr. Forbes read a letter from Mr. McAndrew, 

 then examining the sea bordering the Spanish coast, in 

 which he stated that in the Bay of Vigo, the continuity of 

 the Lusitanian fauna, north and south of it, was interrupted 

 by an assemblage of littoral forms of the British type, among 

 them being a number of Fusus contrarius so common in 

 the (Red) Crag. Mr. Forbes pointed out the bearing of this 

 fact on the land continuity, which he had supposed once 

 existed between South-west Ireland and North-west Spain. 1 



Information about recent observations of scientific interest 

 on the Continent was invited at the 2ist meeting (May 24th). 

 when Mr. De la Rive (guest) stated that M. Pliicker had 

 proved by experiment that when a mass of bismuth of any 

 shape was fused and then cooled between the poles of a power- 

 ful electromagnet, it afterwards would resume that position 

 in regard to those poles ; thus indicating a property of the 

 metal, unless (as was just possible) it contained iron, the 

 particles of which would produce this result by arranging 

 themselves along that axial line. He had also been informed 

 by M. Pliicker that the absolute weight of certain liquids 

 increased under the influence of magnetism without any 

 change of their density. Du Bois-Reymond 2 had shown 

 that if any one held in each hand a metal tube communicating 

 with the terminals of a galvanometer this was deflected, 

 if one arm were held out, the other remaining bent ; but 

 when the converse was done, the galvanometer was deflected 

 in the opposite direction, the positive electricity passing 

 from the outstretched hand through the galvanometer to 

 the curved hand. 



1 See Memoirs Geological Survey, vol. i. pages 336-403. 



* Well known for his researches in electricity and psychology-. Born at 

 Berlin in 1818 ; died there in 1896. 



