Third-person singular simple present indicative form of pumice.(verb)
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Use "pumices" in a sentence
"The upper _Piton_ is unfitted for retaining water, which must percolate through its cinders, pumices, and loose matter into many a reservoir formed by blowing-holes."
"Rhine should produce so soft and charming a liquor, as does the same vine, planted among the rocks and pumices of the so remote and mountainous Canaries?"
"We have now finished the description of the volcanic products of Stromboli; I mean the sand, scoriae, lavas, tufaS; pumices, and specular iron."