CHAPTER XIX 

 THE STEAMBOAT 



1. In what ways are the means of travel on 

 water now in use better than they were when Co- 

 lumbus discovered this continent ? 



2. How is the submarine made so that it is able 

 to travel under water ? 



Early types of boats. Probably the first boat used by 

 primitive man was a log, which may have been propelled 

 by using a tranch for an oar. From this two types of boats 

 developed. One was the dugout, made by digging away 

 the center of a log. Improving on this type, men later con- 



FIG. in. The first boat. 



structed canoes made of bark or other light material. The 

 other early form was the raft, made by fastening several 

 logs together. At first the rafts were propelled by hand ; 

 later, sails were attached to them. 



Eventually the raft developed into a large boat, made by 

 fastening planks and logs together to give it a spoon shape. 

 These early boats were propelled by both oars and sails. 

 At first there was no rudder. About 1 100 B .c. the first rudder 



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