CHAPTER IV.

An Excursion--The Chain of Crosses--Bay of Laig--Island of Rum--Description of the Island--Superstitions banished by pure Religion--Fossil Shells--Remarkable Oyster Bed--New species of Belemnite--Oolitic Shells--White Sandstone Precipices--Gigantic Petrified Mushrooms--"Christabel" in Stone--Musical Sand--_Jabel Nakous_, or Mountain of the Bell--Experiments of Travellers at _Jabel Nakous_--Welsted's Account--_Reg-Rawan_, or the Moving Sand--The Musical Sounds inexplicable--Article on the subject in the North British Review. 66