Thus workers in lead suffer from the effects of this substance as a poison, those who work in phosphorus are liable to necrosis of bone and fatty degeneration of the blood vessels and organs, and the many occupations in which dust is inhaled (coalmining, stone-dressing, steel-polishing, &c.; fig.
For the chronic form of industrial poisoning in the manufacture of lucifer matches - a form of necrosis, known in England as " phossy jaw " and in France as " mal chimique," a localized inflammatory infection of the periosteum, ending with the death and exfoliation of part of the bone - see Match.
No sharp line can be drawn between these diseases and some of the preceding, inasmuch as it often depends on the external conditions whether necrosis is a dry-rot, in the sense I employ the term here, or a wet-rot, when it would come under the preceding category.
The usual necrosis of the injured cortex occursdrying up, shrivelling, and consequent stretching and cracking of the dead cortex on the wood beneath.
Such frost-cracks, sun-cracks, &c., may then be slowly healed over by callus, but if the conditions for necrosis recur the crack may be again opened, or if Fungi, &c., interfere with occlusion, the healing is prevented; in such cases the local necrosis may give rise to cankers.