256 SCIENCE OF HOME AND COMMUNITY 



5. How is the energy of the steam converted into the motion 

 of the wheels ? 



6. What are the uses of the link ? 



7. What precautions are taken to prevent accidents on rail- 

 roads ? 



REFERENCES 



Cressey, Discoveries and Inventions of the Twentieth Century, 



E. P. Dutton, New York City. Chap. 12. 

 Doubleday, Stories of Inventors, Doubleday Page Co., New 



York City. Pages 51-67. 

 Harpers' Machinery Book for Boys, Harper Bros., New York 



City. Chap. 7. 

 Howden, Boys' Book of Locomotives, McClure Co., New York 



City. 

 Williams, How It Works, T. Nelson and Sons, New York City. 



Chaps, i and 2. 





