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…both the Vines, and Cornfields are much bettered by it, and prosper above admiration. For indeed we find by experience, that Turf of the Ground, burnt to Ashes; ans so spread on Land, and ploughed into it, doth yield a very great improvement, even to barren Soyls. Howbeit at this day, much Ground above it lies wast, by means of the ejected Pumice. Besides,…
https://www.wichita.edu/academics/fairmount_las/geology/wparcell/Kircher/volcanoes/chapter6.php