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ZINC v. MANGANESE PHOSPHATING. In response to a reader's query, prompted by an earlier article on the applications of phosphating, a contribution to the French monthly L'Industrie Francaise deals in the February 1961 issue with certain practical aspects of the phosphating process. The author does not subscribe to the suggestion, made by the reader on the strength of German experience, that for cold deformation, manganese phosphate would be better suited than zinc phosphate. Where firms have used manganese rather than zinc phosphate, this is mainly ascribed to the fact that the firms concerned had a manganese bath available, anyway. In general, zinc phosphate has the advantage that layers of a given thickness can be obtained in much less time than equivalent layers obtained by manganese phosphate.