Sold as French ochre, and recommended for priming:
| Parts. | |
| Oxide of iron, alumina | 19.79 |
| Silica | 40.93 |
| Whiting | 11.57 |
| Barytes | 26.64 |
ANOTHER IN OIL.
| Parts. | |
| Chrome yellow | 12 |
| Whiting | 25 |
| Barytes | 63 |
| Oil | 13 |
The markets are flooded with such imitations of ochre, both dry and in oil. The quantity of oil required to grind pure French ochre makes it high-priced, hence there is a motive for putting up barytes, which takes but little oil in grinding.
YELLOW IRON ORE.
Much of the so-called dry ochre on the market is a yellow, iron ore and not yellow ochre. When mixed in oil and put on a tin roof it will turn brown inside of ninety days. I presume you have had experience with such stuff. This makes a bad primer; it is very liable to scale.
CRAWLING PAINT.
When paint crawls it is because there is not sufficient adhesion between the undercoat and the new coat, caused usually by too much gloss on the undercoat. To prevent crawling subdue the gloss on the undercoat by sandpapering, rubbing, or by the application of some material which will have the desired effect; or, if on the outside, wait until the gloss has been subdued by the elements. There is nothing more trying to one’s patience than to have the paint let go and crawl up in bunches after it has been carefully brushed out. Hence, it is well to provide against such trouble in advance. The observing painter has no doubt noticed that paint is more liable to crawl under cornices, and upon other sheltered positions, than elsewhere; hence, it is best in all such sheltered places, where the elements do not have full play, to use sufficient turpentine to prevent a high gloss on the undercoats.