something that cannot be burnt or consumed by fire. See ASBESTOS.

a term in Geometry, used where two lines, when compared to each other, have no common measure, how smallsoever, that will exactly measure them both. And in general, two quantities are said to be incommensurable, when no third quantity can be found that is an aliquot part of both.

INCOMMENSURABLE Numbers, are such as have no common divisor that will divide them both equally.