144 



RELATION OF HEAT TO COMFORT 



to wear clean clothing. Soiled clothing may harbor 

 germs which increase the danger of infection if the 

 skin is cut or bruised. 



Water is a universal cleansing agent. With the 

 addition of soap to water nearly all forms of dirt with 

 the exception of stains may be removed from clothing. 

 Have you ever wondered how soap cleanses? When 

 we wash our hands or clothing with soapy water a 

 soap film forms around little drops of grease, oil, or 

 dirt and forms a lather. This lather is easily removed 

 from our hands or clothing by rinsing with water 

 which carries the dirt particles along with it. 



Dry cleaning and pressing are used on clothing 

 when the use of soap and water would injure the 

 fabrics or cause them to shrink too much. In the dry 

 cleaning process the clothes are usually washed in 

 gasoline or benzine, which removes grease and oil by 

 dissolving them. Possibly you have detected an odor 

 of one of these liquids on clothing that has just come 

 from a dry cleaning establishment. Dry cleaning can 

 be carried on in the home, but carbon tetrachloride 

 should be employed in place of gasoline, benzine, or 

 naphtha. The vapors of gasoline, benzine, and naphtha 

 form explosive mixtures with air, and they are also 

 highly inflammable. Carbon tetrachloride is not in- 

 flammable, nor does it support combustion. Thus it 

 is much safer to use. 



How may stains be removed from clothing? The re- 

 moval of stains is an important problem in connec- 

 tion with the cleaning and care of clothing. The fol- 

 lowing general rules for stain removal are suggested 

 in Thrift Leaflet No. 6, United States Department of 

 Agriculture and Treasury Department. 



Treat promptly. A fresh stain comes out more easily 

 than an old one. 



Find out what made the stain. Some stains are set by 

 treatment that would remove others. 



Consider the material. White and colored goods, cot- 

 ton, linen, silk, and wool should not always be treated 

 in the same way. 



Try simple methods. They often do the work and are 

 not likely to harm the material. 



Work carefully. Experiment on a sample. Rub 

 gently. Haste makes waste in taking out spots. 



Nearly all the common substances used to remove 

 stains may be classified as follows: 



Absorbents materials like blotting paper and chalk 

 that remove stains by absorbing them. 



Solvents materials like water and carbon tetra- 

 chloride that remove stains from fabrics by dissolving 

 them. 



Chemicals which react with the stain with the forma- 



METHODS OF REMOVING COMMON STAINS 



STAIN 



Acids 

 Alkalis 



Blood 



Butter 

 Chewing gum 



Coffee 



Fruit 



Grass and leaves 



Grease 



Ink 



Lubricating oil 

 Iron rust 



Milk and cream 



Oil paints, varnishes, 



and enamels 

 Tar, road oil, and axle 



grease 



Tea and coffee 



HOW TO REMOVE IT 



Apply ammonia water or baking soda. 

 Apply lemon juice, vinegar, or 10% 



solution of acetic acid. 

 Soak in cold water and sponge with 



hydrogen peroxide. 

 Use carbon tetrachloride. 

 Treat alternately with carbon tetra- 

 chloride and water. 

 Wash thoroughly and dry materials in 



sunlight. 



Apply boiling water and oxalic acid. 

 Sponge with alcohol ; then wash. 

 Use carbon tetrachloride. 

 See Farmers' Bulletin No. 1474, U. S. 



Department of Agriculture. 

 Use carbon tetrachloride. 

 Sprinkle stain with salt, moisten with 



lemon juice, and place in the sun. 

 Sponge first with carbon tetrachloride 



and then with water. 

 Sponge with pure turpentine. 



Immerse fabrics in carbon tetrachloride 

 and rub. Follow by thorough washing 

 in soap and water. 



Keep stain moist with lemon juice and 

 expose to sunlight for a day or two. 



tion of substances that are colorless or soluble, or that 

 are both colorless and soluble. 



The table on this page gives methods of removing 

 common spots and stains. Try to place each method 

 in one of the three classes mentioned. 



REFERENCES FOR FURTHER STUDY 

 Texts 



Caldwell and Curtis, Science for Today, Chap. 12 

 Hunter and Whitman, My Own Science Problems, Unit 5 

 Pieper and Beauchamp, Everyday Problems in Science, Unit 

 8 



Powers, Neuner, and Bruner, This Changing World, Chap. 

 14 (part) 



Skilling, Tours through the World of Science, Tour 14 

 Van Buskirk and Smith, The Science of Everyday Life, Chap. 

 IS 



Watkins and Bedell, General Science for Today, pp. 462-466 

 Webb and Beauchamp, Science by Observation and Experi- 

 ment, Unit 4 (part) 



Wood and Carpenter, Our Environment: How We Adapt 

 Ourselves to It, Unit 2, Topic 9; Our Environment: How 

 We Use and Control It, Unit 7, Topic 22 



Special references 



Bassett, The Story of Silk 

 Manchester, The Story of Silk 

 Carpenter, How the World Is Clothed 

 Bassett, The Story of Wool 

 Brooks, The Story of Cotton 



