=Do you remember that we said our clothing must help to save some of the body heat?= That is how clothing protects. Why must some heat be saved? We also learned that when our body works very hard much heat is created. Where does it go? It is not all saved. Why? Our clothing helps to prevent the heat of the body from escaping too rapidly. We should plan to wear light clothing in summer and heavier in winter, or to adapt our clothing to the weather. This is only good sense. In summer we have cool days, and in winter warm ones. People whose habits of living keep them indoors a great deal should be clothed lightly for a warm house and, when going out, should protect themselves with extra clothing. The boy or girl who walks to school rapidly does not require as much clothing as one who rides. Can you tell why? =Have you heard that several layers of thin clothing are warmer than one thick layer?= Frank Allen says he knows why. Yes, because of the layers of air between the thicknesses of clothing. Still air does not carry the heat away, so we feel warmer with several layers of still air. Clothing helps to keep the layers of air from conducting the heat away too rapidly. Porous clothing is always better because air can pass through and can be collected in the meshes. Loose wool material is warm because it holds the air between the spaces made by the woolly fibers. Some day we shall study the wool fiber as we have the cotton, and find out why it collects air and why woolen clothes shrink. Do you think you understand why clothes should be changed at night? Can you tell your big brother at home why? Mollie Stark and Jane Smith told about this part of the story when they went home from school. Mrs. Stark had invited some friends in for tea. All enjoyed hearing Mollie's story. EXERCISES AND PROBLEMS 1. Why is it important to change one's clothing weekly? 2. What care should be taken of the clothing worn at night? Why? 3. How do clothes help to keep us well? Tell mother or father how. 4. Look in your teacher's book on physiology. What does it say about body temperature; about cleanliness of the skin? 5. Write the story of what you think Mollie and Jane told about this subject at Mrs. Stark's tea party. LESSON 10 LACES AND THEIR USE We must finish the sleeves of our nightdresses, and also the neck. Shall we use some lace? Do you know that there are many kinds of lace? How shall we sew it to the gown? Imitation Cluny insertion $.12 Imitation Cluny edging .15 Real Cluny insertion .25 Real Cluny edging .18 German "Val" insertion .09 German "Val" edging .09 French "Val" insertion .13 French "Val" edging .13 [Illustration: FIG. 57.--The names and retail prices of a few good laces for underwear.] Cotton beading $.03 Linen machine-made beading .04