Earth packed and dry 100 Earth dusty 106 Earth muddy 190 Sand loose 320 Gravel good 51 Gravel loose 147 Cinders well-packed 92 Oiled road--dry 61 Oiled road--wet 108 Macadam--very good 38 Macadam--average 46 Sheet asphalt 38 Asphaltic concrete 40 Vitrified brick--new 56 Wood block--good 33 Wood block--poor 42 Cobblestone 54 Granite tramway 27 Asphalt block 52 Granite block 47 TABLE 5 TRACTIVE RESISTANCES TO STEEL TIRED VEHICLES[1] ----------+-----------------+-----------------+-----------+----------- | | Condition | Tractive | Resistance Test No. | Kind of Road | of Road | Total lb. | per ton lb. ----------+-----------------+-----------------+-----------+----------- 29-30-31 | Concrete |Good, excellent | 83.0 | 27.6 | (unsurfaced) | | | [2]11-12 | Concrete |Good, excellent | 90.0 | 30.0 | (unsurfaced) | | | 26-27-28 | Concrete 3/8-in.|Good, excellent | 147.6 | 49.2 | surface | | | | asphaltic oil | | | | and screenings| | | 13-14 | Concrete 3/8-in.|Good, excellent | 155.0 | 51.6 | surface | | | | asphaltic oil | | | | and screenings| | | 9-10 | Macadam, |Good, excellent | 193.0 | 64.3 | water-bound | | | 22-23 | Topeka on |Good, excellent | 205.5 | 68.5 | concrete | | | 8 | Gravel |Compact, good | 225.0 | 75.0 | | condition | | [3]45-48 | Oil macadam |Good, new | 234.5 | 78.2 [4]46-47 | Oil macadam |Good, new | 244.0 | 81.3 38 | Gravel |Packed, in | 247.0 | 82.3 | | good condition | | 18-19-20 | Topeka on plank |Good condition, | 265.0 | 88.3 | | soft, wagon | | | | left marks | | 34 | Earth road |Firm, 1-1/2-in. | 276.0 | 92.0 | | fine loose dust| | 24-25 | Topeka on plank |Good condition, | 278.0 | 92.6 | | but soft | |