J. W. Judd — On Volcanos. 5 



Mediterranean islands lying between the Phlegraean Fields of 

 Calabria and Sicily. Etna, it is true, presents us with the monu- 

 ments of igneous forces acting upon a grander scale, and Vesuvius 

 excites a livelier interest by its historical associations, its fossil cities, 

 and its proximity to a splendid capital ; but neither of these volcanos 

 can vie with those of the Lipari Islands, either in the remarkably 

 • suggestive features of their structure, in the permanent and interest- 

 ing characters of their operations, or in the variety and beauty of 

 their products. 



Nor have the advantages here presented to the geologist been 

 neglected by the pioneers of our science. Sir William Hamilton, 

 Dolomieu, Spallanzani. and Scrope have, by the study of their active 

 and extinct vents, contributed much towards our knowledge of the 

 modus operandi of volcanic forces ; Hoffmann, Allan, and Abich have 

 described the interesting rocks of which the Lipari Volcanos are 

 composed ; while the last-mentioned author, with Daubeny, Charles 

 Ste. -Claire Deville, Fouque, and Janssen, have investigated the 

 nature and products of the chemical actions going on within them. 



The geological interest attaching to the volcanos of the Lipari 

 Islands has induced the French Academy to send out, on several 

 different occasions, commissions charged with their investigation- 

 Many undertakings, which in other countries require an appeal to 

 the resources of the Government, are in our own safely left to in- 

 dividual enterprise ; and Mr. Scrope, who more than fifty years ago 

 experienced and called attention to the advantages which the Lipari 

 Islands offer as objects of study, has furnished several students of 

 volcanic geology, myself among the number, with the opportunity 

 of carrying on researches in them. 



As no general sketch of the geology of the Lipari Islands has 

 been published since the admirable, but now somewhat obsolete, 

 work of Friedrich Hoffmann, which made its appearance in 1834, it 

 has been suggested to me that an account of some of the results of 

 my own studies there in the spring of 1874 would be of interest to 

 the readers of this Journal. The sketch which we are here able to 

 give must, of course, be mainly descriptive, and it will be impossible, 

 within its limits, to enter into detailed discussions of those numerous 

 problems of volcanic geology, towards the solution of which this 

 interesting group of islands affords such valuable materials. 



The name by which this group of islands (a Sketch-map of which 

 is given on page 7) is generally known is derived from its central, 

 largest, and most populous member. An earlier designation, and 

 one which is still often applied to them, is that of " the Eolian 

 Isles," and there is a curious interest attaching to its derivation. 

 The original Eolus appears to have been a prince or chief of the 

 Greek colony which inhabited these islands, and, being probably a 

 man of superior intelligence and shrewdness, he seems to have ac- 

 quired some fame by employing the two active volcanos of his 

 dominions as natural " weather-glasses." Stromboli is still believed 

 by the Liparotes to respond, like a barometer, to changes of atmo- 

 spheric pressure ; and the characters of the vapour-clouds which rise 



