420 QUESTIONS ON 



CHAPTER XIV. 



689. Is the exercise which health requires, the limit of muscular 

 power ? 



690. What questions are important for the laborer? 



691. How can the laborer know he has overworked ? How long 

 may he increase his exertions ? 



692. How can he maintain the fulness of his strength ? 



693. Has man an indefinite power of endurance? 



694. How is premature old age sometimes induced ? 



695. What is a common effect of overworking ? Illustrate. 



696. Among what class is the length of life shortest? 



697. May not other circumstances account for the shorter life of the 

 day-laborer and sailor ? 



CHAPTER XV. 



698. Does excessive labor for a short period produce the same kind 

 of result? 



699. What permanent injury often results ? Illustrate. 



700. Who suffers most from great exertion ? 



701. When does a man acquire full strength? What is the ordei 

 of development of power? 



'CHAPTER XVI. 



702. Why does labor require healthy organs of digestion and nutri- 

 tion ? 



703. What kind of food does labor require ? Why? 



704. What kind of food should a laboring man eat? Why ? 



705. Can a man labor well whose skin and lungs are not in a healthy 

 condition? Why? 



706. How do diseases of the heart unfit for labor? 



707. How do the state and health of the brain and mind affect the 

 ability to labor? 



708. 709. What is the proper state of the brain and mind while 

 taking exercise ? 



CHAPTER XVII. 



710. What motive does labor for profit require ? 



711. What are the effects of hope and despair on labor? 



712. What of confidence, and of doubt? 



713. What is the effect of cheerfulness and of melancholy? 



714. What is the effect of alcoholic liquors? 



CHAPTER XVIII. 



715. What is the natural form of the spine ? How is the head held ? 



716. Describe the muscles of the back? 



717. How does a curvature of the spine affect the muscles of the 

 back? 



