The walls must be first properly prepared. The treatment varies, of course, depending upon the condition of the walls. If the walls are new, they should be perfectly dry, and if the lime is still caustic it must be treated with some neutralizing substance, as directed in another part of this book. If the walls are damp, they must receive a coating of shellac, or waterproof size, otherwise the new paper will soon discolor and mildew. A waterproof size of thin shellac varnish or shellac water varnish made as directed under shellacs, will answer all purposes. In all cases, walls should have a coat of glue size before being papered. Where very fine work is required, it is advisable to first apply lining paper to the walls which will give a smooth foundation to work upon and will protect the wall paper from stains striking through. In repapering, the old paper should be removed. If left on, it is unsanitary and will render it more difficult to produce a good job. "Washing down the old paper with hot water applied with a brush soon loosens the paper so that it readily scrapes off. When the walls are very bad and uneven, battens may be nailed to the walls and burlap stretched over them. The wall paper can be hung on the burlap after it has been sized. If a whitewashed wall is to be papered, the white wash must be removed by moistening it with hot water and scraping.

To determine the number of rolls of paper needed: measure the circumference of the room in feet, deduct the width of the doors and windows and divide by three, which will give the number of rolls required for a room from 10 to 12 feet in height. When the wall is less than 10 feet high, after subtracting the width of the doors and windows from the room's circumference, multiply by two and divide by fifteen.

Light shades of paper make a room more cheerful.

Large figures make a room appear smaller. Low rooms should have a striped paper running up and down to give a heightened effect. If the room has many windows, use subdued tints. It is always best to use quiet colors which do not attract too much attention and which do not render the furniture prominent. Dirty wall paper may be cleaned by preparing a mixture of 4 pounds of wheaten flour kneaded into a stiff dough, with 7 pints of water. Wipe the paper all over with this.