ZINC CHLORIDE Zinc chloride, which is obtained by dissolving metallic zinc in hydrochloric acid, is a cheap and very good wood preservative, its toxic effects upon wood-destroying fungi being about equal to those of creosote; also it has an affinity for wood fiber into which it penetrates to a considerable depth. Its chief fault is that it attracts water and dissolves easily in it. Experience shows, however, that it will remain in timber in reasonably dry locations for many years. It cannot be used in marine constructions, but has caused railway ties which would normally fail in four or five years to remain sound for ten or more years. Many million pounds of zinc chloride are now used annually in the United States in treating wood.
Zinc chloride is the cheapest wood preservative practically available in this country, and in spite of defects that have led most European railways to cease using it, is highly regarded as an antiseptic that meets some temporary American conditions. Burnett first called attention to the value of zinc chloride as a wood preservative in 1838.