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LOGGING 



in streams actually navigated by steamboats in such manner as 

 to obstruct, impede, or endanger navigation." 



There are a variety of forms in which rafts are built, depending 

 on the character of the water on which they are to be towed, 

 the kind of timber rafted and on the Federal regulations ^ gov- 

 erning rafting. 



Bag or Sack Booms. — These are used on the Great Lakes and 

 on large, smooth rivers. They consist of a single or double row 

 of boom sticks surrounding the impounded logs. For lake work 



Fig. 



A Mississippi River Lug Raft, sliowin; 

 End-wheel Steamers. 



the Method of Control by 



short boom sticks of large size are preferable because loose logs 

 are less apt to slip under them than they are under the long ones. 

 On the Great Lakes double booms with connecting chains made 

 of i|-inch iron are considered superior to single booms. During 

 the period when the exportation of logs was permitted by the 

 Provincial Governments of Canada, immense quantities of white 

 pine were rafted to this country and manufactured at points 

 along the Great Lakes. The season for towing was from June i 



1 The Federal government specifies the form, size and character of rafts that 

 may traverse certain navigable waters and harbors. 



