160 



AGRICULTUBE. 



EFFECTS OF SURFACE ON TRACTIVE FORCE. 



(Various Authorities, compiled by Herring.) 



Description of Road. 



Loose sand 



Loose gravel (deep) . . . . 

 Loose gravel (4 inches) . 

 Common gravel road , . . 



Good gravel 



Hard-rolled gravel 



Ordinary dirt road 



Hard clay 



Hard, dry dirt road 



Macadam, little used. . 



Macadam, bad 



Macadam, poor 



Macadam, common 



Good macadam, wet . . . 

 Best French macadam.. 



Tractive 

 Force, 

 Lbs. 



448 

 320 

 222 



147 

 88 

 75 



224 



140 to 97 

 160 

 112 

 64 

 75 to 42 

 45 



Description of Road. 



Very hard and smooth 



macadam 



Best macadam 



Cobblestone, ordinary ... 



Cobblestone, good 



Belgian block 



Belgian block in Paris . . . 



Belgian block, good 



Stone block, ordinary 



Stone block, good 



Stone block, London 



Asphalt 



Granite tramway . . . . 



Iron railway 



Tractive 

 Force, 

 Lbs. 



46 



52 to 3a 



140 



75 

 56 to 26 

 54 to 34 ■ 



34i 



90 



45 

 36 



12^ to I3J 



8 to 11^ 



The velocity is in all cases taken at 3 miles per hour. 



COST OF HAULING FARM PRODUCE IN THE 

 UNITED STATES. 



* Middle States. 



The total weight of farm products in 1895 was estimated 

 at 219,824,227 tons ; if the forest products hauled over the 

 public roads be added to this, we get 313,349,227 tons, 

 which at $3.02 per ton, makes a total for the annual cost of 



