The Ten Books on Architecture, 7.13.3

Vitruvius  Parallel editions

‹‹‹ Vitr. 7.13.2 | Table of Contents | Vitr. 7.14.1 ›››

Gwilt translation

3After the shells are gathered they are broken into small pieces with iron bars; from the blows of which, the purple dye oozes out like tears, and is drained into mortars and ground. It is called ostrum, because extracted from marine shells. Inasmuch as this colour, from its saltness, soon dries, it is prepared for use with honey.

Morgan translation

3After the shellfish have been gathered, they are broken up with iron tools, the blows of which drive out the purple fluid like a flood of tears, and then it is prepared by braying it in mortars. It is called “ostrum” because it is taken from the shells of marine shellfish. On account of its saltness, it soon dries up unless it has honey poured over it.