PART VI. DEVICES FOR LABOR 

 SAVING AND CONVENIENCE 



CHAPTER XXI 



SOME SIMPLE MACHINES IN THE HOME 



Problems. i. To understand the principles underly- 

 ing simple machines used in and about the house. 

 2. To understand what advantages machines offer. 



Experiments and demonstrations. i . To demonstrate the principle of 

 levers. 



2. To illustrate changing speed by use of wheels of different diameters, 

 joined by belt or gears. 



Project 1. To KEEP THE MACHINES OF THE HOME IN GOOD WORK- 

 ING CONDITION. 



1. Learn how to operate all the different household machines. 

 Learn what oiling is necessary, and how to keep free from dust 



and dirt. 



2. What other attention is needed from time to time? 



3. Study the mechanism of the more complicated machines to 

 know how the machines work. 



4. If needed repairs are too difficult for you to do, be ready to 

 advise where repairs should be made. 



Suggested Projects. 



I. TO DETERMINE THE TYPES OF MACHINES AND THE MECHANICAL 

 ADVANTAGE OF TEN DIFFERENT MACHINES FOUND IN MY HOME. 



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