50 



A PRIMEK OF FORESTRY. 



driven singl}- down the riv^er. The log drivers who do 

 this work learn to balance themselves on the floating, 

 rolling logs, and walk on them almost as easily as on 

 the solid ground. Sometimes locomotives drag the 

 logs behind them over the ties, or they are hauled on 

 cars which run over poles cut in the woods instead of 



Fig. 34. — A sawmill, log pond, and lumber yard. Northern California. 



over metal rails; often they are rolled into slides built 

 of other logs, and either move downhill by their own 

 weight or are dragged along by horses, cattle, or steam. 

 In southern swamps the logs are sometimes swung up 

 by a wire rope suspended from the trees, and so are 

 loaded on the great llatboat which carries them to the 

 mill. 



