III. Zinc-white paints applied on zinc, Portland cement, or iron (the latter having previously been provided with first coats of red oxide of lead or iron), are able to withstand the action of the open air for a space of five years quite as well as white-lead paints, and can entirely replace the latter, provided they are not exposed to the action of vapours containing sulphurous acid. IV. In the interior of buildings zinc-white paints, applied on wood, iron, zinc, Portland cement, and plaster, are as good as white-lead paints; and can entirely replace the latter, provided they are not exposed much to vapours containing sulphurous acid or to much damp. V. Zinc-white paints applied on wood, if not exposed much to the action of sulphurous acid gas, will in many cases last during five years in the open air as well as white-lead paints, and can replace the latter with good results. But in all places where water accumulates, as on window-sills, the lower side of cornice-work, etc., they will, even after three or four years, deteriorate to such a degree that repainting will become necessary for the preservation of the wood; in this respect, therefore, they are inferior to white-lead paints. VI. Zinc-white paints, such as the White Lead Commission have used successfully, cover at least equally as well as the white-lead paints customary in this country. The zinc-white putty used by the White Lead Commission is quite as serviceable as ordinary white-lead putty. VII. Painting with zinc-white paint, such as the Commission used on new woodwork in the open air, does not cost more than painting with the white-lead paints customary for that purpose. VIII. Painting on existing paintwork, so-called “repainting,” in the open air, with zinc-white paints such as the White Lead Commission used, costs more than the white-lead paints hitherto in use, inasmuch as the preparation of the wood painted with zinc-white paints involves greater expense in rendering it fit for the repainting than in the case of wood painted with white lead in rendering it fit for further painting with white lead. In the case of painted wood which is exposed to the open air, the possibility is, moreover, not excluded that, where such wood is in an unfavourable condition of humidity (see under § V.), it may have to be repainted sooner than if it had been painted with white-lead paints. In these circumstances the cost of maintenance of wood painted with zinc-white paint, and exposed to the open air, is further increased as compared with wood painted with white-lead paint. IX. Lithopone paints cannot replace white-lead paints in the open air; they have proved to be quite unfit in this respect. X. For paintwork above water, first coats of oxide of iron have, during five years, proved to be quite as good and serviceable as first coats of red oxide of lead.