Note 8 — Chapter II · ETNA.
Reading edition
"Report on the Chemical and Mineralogical Characters of the Lavas of Vesuvius from 1631 to 1868," Transactions of the Royal Irish Academy, vol. xxvi. (1876). In the lava of 1848 leucite was found to reach 44.9 per cent. of the whole mass. In that of Granatello, 1631, it reaches its lowest proportion—viz., 3.37 per cent.