Q. 4319. Cause of Rusty Paint.

Manufacturer and Builder 1, 1890

Can you state why most kinds of paint applied to houses, assume such a rusty appearance in the course of a few months? For painting our houses, I purchase the best of white lead (or I pay for what is sold as white lead of the best quality), with which is mingled Brandon yellow (about equal quantities), and sometimes a little umber is added. We purchase linseed oil of the best quality, using about equal quantities of boiled and crude oil in warm weather, and boiled oil only in cold weather. In less than one year alter the paint is applied it fades and becomes rusty, and appears as if no paint had been applied for several years. What is the cause? and what would be a good remedy?
— Ess. E. Ton, Orange, N. J.

Answer. The general discoloration of white-lead paint on woodwork, is due partly to the darkening of the vehicle (linseed oil) in drying out, which will contribute to give it a yellowish or brownish tinge; and partly to the action of sulphurous and other impurities in the atmosphere. If this explanation is the correct one, zinc white ought to retain its proper color in a mixture longer than lead, since its sulphur compound is white in color.

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