Wash with a solution of bi-chromate of potash and acid water. One ounce to a quart of water.
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.
HOW TO APPLY WHITE ENAMELED LETTERS TO GLASS.
An extract from a circular issued by the manufacturers of these letters:
Having thoroughly cleaned the window and freed it from grease, draw with white marking chalk on front of it the plan or arrangement of outline it is intended to adopt—straight or curved, as the case may be. A rule is used for marking the straight lines and a piece of twine for the curved lines. Now divide these guide lines up into as many spaces as there are letters to go on, carefully proportioning them. Then apply the cement to the back of the letters with a knife, laying on equally around both the inside edges. Place the letter upon the window in the space marked for it and work it up and down, back and forth, pressing against the glass, so as to expel the air and secure a good adhesion, and taking care to press equally on top and bottom of the letter, as otherwise there is a likelihood of breaking. It is advisable, in cementing larger sized letters than six inches, to leave the letters lay for an hour after placing the cement around the edges, and then to give another coat of cement and attach the letters immediately. The object is to prevent all the cement from working inside the concave parts of the letters. In affixing larger and heavy letters, small pieces of beeswax (or, in summer, sealing wax) should be employed to keep them in position until the cement sets. As soon as the letters are attached to the glass take a small stick of wood, sharpen it on the end and clean away all superfluous cement, keeping the end of the stick constantly wet. Particular care should be taken to leave no openings between the letters and the glass (especially around the top edges) which would allow water to get in between.
If wax has been used, remove it after a few days and clean with a rag. The sign is then complete for long service. The above method will answer equally well on any smooth surface such as stone, iron, marble, wood.
To make the cement, mix two parts of white lead ground in oil with three parts of dry white lead, and thin it down to the consistency of soft putty with some good furniture or copal varnish. Then take small parts of it and grind them on a stone or glass plate in the manner of painters grinding color with a bowl or palette knife. This is to be continued until the cement is entirely smooth and cornless, and then it is ready for use.
To remove enameled letters, the most convenient way is to scratch away around the edges all the cement you can from under the letters. Use for this purpose a very thin knife or a piece of thin sheet steel. You will soon reach the soft part of the cement; then cut away with a sawing motion and twist them off. Do not attempt to pry the letters off, or they may break. If the cement should be very hard, say after a number of years, use a little kerosene oil, which is applied on the top edges of the letters, so as to work in and soften the cement.