740 



HO ADS 



of Knglu/i Hutory) given them as follow*: 'The 

 Watling Street representa the old zigzag route 

 from Kent to Chester ami York, and northwuids 

 in two branches to Cuili-le ami the neighlnmihiMid 

 of Newcastle. Tlie Fume \Viiv run diagonally 

 through liuth to Lincoln. The Ermin Street led 

 direct from London to Lincoln, with a branch to 

 Doncaster and York; and the obscure Ik.-niM 

 Street curved inland from Norwich to Uunstable, 

 and was carried eventually to the coast at Smith 

 ampton. ' Walling Street and Ikenild or Icknield 

 Street have separate articles in this work. 



The roads made by the Romans in (ireat Britain 

 gradually fell into decay, and the attempts that 

 were now anil then made to repair them were. 

 insufficient to prevent England falling into a \vm-e 

 state with res|>ect to ita highways than most 

 other European countries. In 1285 one of the 

 earliest laws on the subject of roads was passed. 

 It directed that all trees and shrulis be cut down 

 to the distance of 200 feet on either side of roads 

 between market-towns, to prevent the concealment 

 of robbers in them. The first toll for the repair 

 of roads was levied by the authority of Edward III. 

 in 1346, on roads which now form part of the 

 streets of London. In 1555 an act was passed 

 requiring each paiish to elect two surveyors of 

 highways to keep them in repair by compulsory 

 labour ; at a later period, in place of the compulsory 

 laliour, the ' statute labour-tax ' was sulwtituted. 

 But Ion;.' after this the roads even in the neighbour- 

 hood of London were wretchedly l>ad, and in the 

 other parts of the country they were still worse. 

 For tlu 1 most part, indeed, they were mere horse- 

 tracks ; the chief advantage in following them 

 Ix-inx that they led along the higher grounds, and 

 so avoided l>ogs. These trackways were usually 

 impassable In winter, being narrow, and in many 

 places so d....|i ami miry as to be liker ditches than 

 roads. So late as 1730 the roads in the iieighUxir- 

 Imoil of London were so bad that in wet weather a 

 carriage could not be driven from Kensington to 

 St James's Palace in less than two hours, and 

 sometimes stuck in the mud altogether. Much 

 curious information on the state of the roads and 

 means of conveyance in England during the long 

 period which elapsed from the decay of the Roman 

 roads to the middle of the 18th century, will Ill- 

 found in vol. i. of Smiles ' Lives of Engineers. The 

 Highlands of Scotland were opened up by the 

 roads made by General Wade about 1725. 



In laying out a new line of road the skill and 

 ingenuity of the engineer are taxed to make the 

 gradients easy, with as little expense as possible in 

 excavating and embanking, and to do so without 

 deviating much from the direct course between 

 the fixed points through which the road must pass. 

 To succeed well in this an accurate survey of the 

 tract, including the relative levels of ita different 

 parta, and the nature of the strata, is a necessary 

 I'li'limiriary. The formation of an extended lim- "f 

 road often involves the construction of extensive 

 bridges, viaducts, and the like, which require the 

 greatest engineering skill. 



The importance of easy gradient* or inclinations 

 in roads is well understood in a general way : but 

 it gives a more precise idea of it to state that, 

 while, for example, the traction force requisite to 

 draw a wagon weighing 6 tons along a level 

 macadamised road is 264 lb., on a road of the same 

 kind with an ascent of 1 in ~>0 the traction force is 

 just double, or 533 lb., the speed of the wagon being 

 3 miles an hour. Compared with this, a stage- 

 coach travelling on the level at the rate of 6 miles 

 an hour, ami weighing 3 tons, requires a traction 

 force of 362 lb. ; but the resistance on a hilly road 

 i- leas unfavourable to the coach than to the wagon, 

 with an incline of 1 in 70 the forces necea- 



\ 



Miry to draw the two vehicles are about equal, and 

 the force is proportionally greater for the wagon as 

 the incline increases. Experience seems to show- 

 that fora macadamised road the maximum slope 

 should be 1 ill 40, although a horse with a moderate 

 load can easily enough trot over a gradient of 1 in 

 33. On the other hand, as it is not desirable for 

 drainage to have a road perfectly level, the best 

 minimum slope, in a longitudinal direction, has 

 been variously given at from 1 in HO to 1 in I'J.Y 

 The resistance to moving vehicles is less on paved 

 than on ' metalled ' roads ; hence the maximum 

 slope of the former should be less than that of tin- 

 latter, from the greater tendency of a cart or coach 

 to slide down the smoother surface. 



What is the best transverse form for a road has 

 been a much-debated question among engim-ei-. 

 It should be higher in the middle than at the sides ; 

 but some have thought it should he much higher 

 than others. As a road can be better kept clear of, 

 water by a slight inclination in the direction of ita 

 length than by any form which can be given to its 



FENCE 



Cross Section of a Road : 



A, foundation of rough pavement or concrete; B, broken 

 atone*. 



cross section, it has l>een found preferable that it 

 should be as nearly Hat as possible, because every 

 part of its breadth will then be equally available 

 for traffic ; whereas it is almost necessary to keep 

 on the centre of a highly convex road, and con- 

 sequently wear deep furrows there, by confining 

 the wheels and horses to pretty mucfi the same 

 track. The figure shows a transverse section of a 

 road in the form of a segment of a circle the most 

 approved form with only a slight rise in the centre. 

 The slope from the side to the middle should not 

 exceed 1 in 36. 



As respects the construction of the road iteelf, 

 the nrstpoiiit to consider is the foundation or sub- 

 road. Tlie majority of roads have no artificial 

 foundation. In sucli cases the surface on which 

 the road -material is to be laid is generally made as 

 solid as possible by means of efficient drainage, and 

 by rolling and beating wherever there are embank- 

 ments formed. It is the question whether or not 

 a road should have a foundation of rough pave- 

 ment In-low the broken stone covering which is the 

 essential |>oint of difference between the two great 

 rival MM ems of Telford and Macadam. Teliord, 

 who began to construct roads in 1803, con- 

 sidered it of great importance that there should 

 be such a foundation. He made it of stones 

 varying in depth from 9 inches at the centre to 

 3 inches at the sides of the road, these being 

 set with their broadest edge downwards, and no 

 stone being more than 4 inches brood upon the 

 upper edge ; upon these were placed a coating of 

 broken stones not exceeding inches in thick- 

 ness. The Glasgow and Carlisle and the Holyhead 

 roads are excellent examples of the enduring 

 character of those made on Telford's plan. 



Macadam (q.v.) preferred a yielding and soft 

 foundation to one which was rigid and unyielding, 

 so that even on Imggy ground, if it were but 

 firm enough to allow of a man walking over it, he 

 considered an artificial bottoming quite unneces- 

 sary. His roads were formed entirely of angular 

 pieces of stone of such a size as to pass freely 

 through a ring 2J inches in diameter. This 

 plan, first put into practice about 1816, has 

 now fewer advocates than Telford's, or than 



