PROJECTS 593 



Arrange the covering so that the door may be opened without 

 unbuttoning the edges of the covering. In order to do this, the 

 cover on the front of the case must be buttoned to the top and 

 bottom and latch panel of the door, as shown in Figure 14. Another 

 row of buttons fastens the other vertical edge of the covering to 

 the framework at the opening of the door. Make sure that the 

 hems on these vertical edges are extended far enough to cover the 

 crack between the frame and the closed door. 



Sew to the top edge of each side of the covering a double strip 

 of the same kind of cloth. Make these strips long enough to extend 

 about 3 inches into the biscuit pan on top of the case, and taper 

 these strips to a width of 8 inches. 



Keep the upper pan filled with water. The strips of cloth serve 

 as wicks to supply the sides of the covering with moisture (Experi- 

 ment 97, p. 325). The lower pan is to catch the drippings from 

 the covering. A small amount of water in the lower pan also serves 

 the excellent purpose of keeping ants and other insects from the 

 refrigerator. The only inconvenience about the operation of the 

 refrigerator is that the wicks attached to the door must be wrung 

 dry whenever it is opened. 



Put the refrigerator in a shady place where the air circulates 

 freely. On dry hot days a temperature as low as 50 F. may be ob- 

 tained in one of these coolers. When the air is full of moisture, 

 the refrigerator will not work so well. Explain this. On such days 

 more water will drip into the lower pan. 



PROJECT XXIII. How to Make a Substitute for a Vacuum Bottle, 



page 92 



A very serviceable substitute for a vacuum bottle may be made 

 of a three-pound coffee-tin, a small amount of asbestos insulating 

 cement (such as is used to cover steam boilers and steam pipes), 

 a yard of cheesecloth, and a bit of flour or library paste, two or 

 three old newspapers, and a Ball-Mason quart jar (Figure 15). 



A Ball-Mason quart jar measures 7 inches in height and 3 inches 

 in diameter at the base. An ordinary 3-pound coffee-tin is about 



