The English name for this kind of paint is distemper; and these fresco or distemper paints are often sold in bottles or jars ready for use, containing some preservative to prevent decomposition of the glue or other binding materials.
Kalsomine is sold, ready mixed, in packages; these are emptied into hot water, stirred until the glue is dissolved, then allowed to cool before using.
Recently kalsomine has been put on the market which dissolves in cold water and is ready to use at once; this is very convenient and satisfactory. A much greater variety of color effects can be had with kalsomine than with whitewash, and it has a softer and smoother appearance, free from the somewhat rough and sandy look of whitewash, especially when put on a little too thick; but it has not the antiseptic qualities of the latter. White- wash costs almost nothing; it is sanitary, easily applied, may be so made as to resist the weather tolerably well, and is and always will be thepaint for the million. Kalsomine is used almost solely for its artistic effect, in which it is equaled only (if at all) by the most costly enamel painting. On plain work it is easily applied, but it also lends itself to display the highest skill of the artist. Some of the most celebrated pictures in the world are fresco paintings.
Cold-Water Paints
These are related both to whitewash and to kalsomine; to the former because they contain quicklime, and to the latter because they contain a glue-like cementing material. The cement is casein which is obtained from milk. Milk consists of water, sugar, casein, and fat (butter), the last three in about equal proportions. When the butter is removed the casein may be precipitated, purified, and dried, and it is on the market as a white powder, soluble in a solution of any alkali in water. In the early days of cold- water paints borax was used; but this was a failure, because the compound formed by it and casein was not altogether insoluble when dry. Now the casein is mixed with lime; when water is added to this mixture the casein first dissolves in the lime-water, then it combines chemically with more lime, and this lime and casein compound, when dry, is insoluble and is a cement of considerable strength. As the paint is put up in dry form, it is a powder containing, like kalsomine, whiting and coloring matter, and the proper amount of casein and powdered quicklime, the latter two taking the place of the glue in kalsomine.