SIZING WALLS.
“Anybody can do it!” Yes, but it takes an expert to do it right. It is not a difficult matter to make paper stick to whitewash, but the whitewash splits as far in as the paste goes, and a part of it invariably sticks to the paper when it comes off and a part of it is left on the wall. As a rule, if you size whitewash with flour paste and let it stand a few days it will crack and roll up. Now, pure glue size does not have this effect upon whitewash, but, on the contrary, it not only acts as a binder, but as an intervening coat between the paste and the whitewash. In other words, the glue size will stick the whitewash fast without causing it to crack, and the paste will adhere to the glue size without bad effects upon either. Now, in order to bind the whitewash, the glue should penetrate as far as possible. Hence, the size should be put on warm, and the room should be warm, otherwise the glue will get cold and stiff like jelly before it has time to penetrate; hence it will remain on the surface instead of going into whitewash as a binder. The idea is to get all you can into the wall and leave as little as possible on the outside. Another thing to look after is the quality of the glue. Very much of the white glue found on the market is not genuine glue. Some of it is adulterated with starch and white clay, some of it is not glue at all. A glue which will dissolve in cold water is not good glue, or if it melts readily in hot water without being soaked an hour or two in cold water, it is not first-class. If it has a dead white look it is not good. Good glue should be glossy and semi-transparent, and should soften and swell in cold water, but not dissolve in it. When put into hot water without being first soaked in cold water, it should not dissolve at once, but form into a lump and resist the action of the hot water for some time.