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Abstract of a Paper accompanying a Suite of Volcanic Rocks from 

 the Lipari Islands, presented to the Royal Society. By 

 ROBERT ALLAN, Esq. F. R. S. E., M. G. S., &c. 



(Read 16th January 1833.) 



HAVING frequently had the pleasure of examining the very in- 

 teresting and highly valuable . collection of volcanic specimens 

 brought from Iceland, and presented to the Royal Society by 

 Sir GEORGE MACKENZIE, I was gratified in an opportunity which 

 was afforded me, at the close of 1830, of visiting the Lipari 

 Islands, the only other great repository of obsidian in Europe, 

 and of there collecting the suite of specimens which I have now 

 the honour of presenting to the society. Unfortunately, it is far 

 from complete as a geological series ; for the difficulties occasion- 

 ed by the tempestuous state of the weather, and the impossi- 

 bility of getting to the more remote islands in a small boat du- 

 ring the month of December, limited my movements extremely, 

 and forced me to confine my observations to the two principal 

 islands of the group, viz. Lipari and Vulcano. I do not there- 

 fore pretend to give any geological account of these islands, or 

 even of the two on which I landed. My object in collecting, and 

 consequently also in presenting to the Society, this series of speci- 

 mens, was to afford the means of comparing with each other the 

 productions of the two great obsidian districts of Europe ; those 

 from Lipari, which are now on their table, with the Iceland suite 

 already in their possession. 



VOL. XII. PART II. 3 Y 



