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HIGHWAY CONSTRUCTION 



hand rollers, either with or without a fire-pot (Fig. 68); and steam 

 rollers, with or without provision for heating the front roll (Fig. 66). 

 These rollers are different in construction, appearance, and weight 



Fig. 68. Hand Rollers. 



Fig. 69. Pouring Pots. 



from those employed for compacting broken stone. The difference 

 is due to the different character of the work required. 



The principal dimensions of a five-ton roller are as follows : 



Front roll or steering-wheel. 30 to 32 inches diameter. 



Rear roll or driving-wheel 48 " 



Width of front roll 40 " 



" " rear " 40 " 



Extreme length 14 feet. 



" height 7 to 8 feet. 



Water capacity 80 to 100 gallons. 



Coal " 200 pounds. 



