420 A YEAR IN SCIENCE 



10. Why should we place no confidence in phy- 

 sicians who advertise? 



11. Discuss the value of patent medicines. 



12. What do you understand by the term immunity ? 



13. It has been estimated that a typhoid fever germ 

 may travel about 2,000 times its own length in one hour. 

 A cholera germ may attain a speed that is 45 times as 

 great as that of the typhoid bacillus. If a man should 

 travel as many times his own length as the typhoid 

 bacillus or cholera spirillum, how far would he travel in 

 one hour ?* 



*From Bevgen and Caldwell, Practical Botany, Ginn and 

 Company. 



