PROJECTS 



599 



washing soda. After cleaning the refrigerator, replace the ice 

 and close the doors for a while before replacing the food. An 

 iced refrigerator dries much more quickly with the doors shut than 

 an un-iced refrigerator will dry with the doors open. 



PROJECT XXVI. How to Install Devices for Ventilating, pages 



113-114 ^ 



Full instructions are given on pages 113-114 for making ventilat- 

 ing boards and screens. Measurements must depend on the size 

 of the window to be fitted. 



In the case of cloth screens, the simplest way to get measure- 

 ments is simply to duplicate the frame of the summer screen and 

 then substitute muslin for wire screening. 



PROJECT XXVII. How to Siphon Cream from a Bottle of Milk, 



page 119 



To remove cream from a bottle of milk with a spoon or patent 

 cream dipper is a difficult and often a wasteful operation. The 

 cream or top milk may 

 be much more easily 

 and effectively removed 

 with a glass siphon. 



Bend a piece of glass 

 tubing in the labora- 

 tory into the form of 

 a siphon (Figure 17). 

 Have the two arms of 

 the siphon close enough 

 together so that the 

 loop may be inserted in 

 a milk bottle as shown 

 in A, Figure 17. 



To start the action of the siphon, dip the short arm of the siphon 

 into the cream, as in A, Figure 17, allowing the cream to run in and 

 fill the short arm, and the long arm to the depth of the short arm. 



FIGURE 17. 



