358 



ROADS. 



tracks. 



.Roads and Scotland, vol. vi. this mode of making a smooth and du- 

 ighwaya. ra b] e rO ad, by laying tracks with stones not much lar- 

 "~~V* 1 "' ger in their cubic contents than those of aisler causeway, 

 is described as equally applicable to the streets of a 

 city and the acclivities of the highway. Indeed, 

 judging from the duration of causewayed streets, such 

 is the comparative economy of this system, that we 

 despair not of seeing it very generally used on our 

 public roads. It appears to have been first proposed 

 for the main-street of the town of Linlithgow, which 

 forms part of the great western road through Falkirk 

 to Stirlingshire, by Mr. Stevenson, engineer. Spe- 

 cimens of these tracks have been submitted to the 

 inspection of Lord Melville and to some of the lead- 

 ing road-trustees of the county of Edinburgh, and 

 to several of the commissioners for paving the streets 

 of the parishes of London, where it is expected to be 

 submitted to trial. This plan will be readily understood 

 PLATE by examining Figs. 1 and 2, Plate CCCCLXXX. and 

 CCCCLXXX. j tg ] etter .p ress description at the end of this article, in 

 'S s< > w hich a street or highway, supposed to measure about 

 thirty feet in breadth, is laid out in five compartments, 

 independently of the footpaths. Two of these are pav- 

 ed with the aisler causeway tracks, laid five feet apart, 

 while the intermediate spaces for the horse-paths may 

 either be of ruble causeway, or broken stones in the 

 usual way. 



Description The tracks may be formed of granite, greenstone, 

 of the or anv O f t^e hard varieties of rock which is capable 

 of being dressed with a hammer, to dimensions not 

 less than the following ; say, from six to eight inches 

 in the length way of the track, twelve or fourteen 

 inches in depth, eighteen inches in breadth at the base, 

 and twelve inches at the top or wheel-track. The sides 

 of the stones where they come in contact with each 

 other, are to be dressed so as to form a plain close joint 

 across the track, and the top is to be flat, that carriages 

 may move without obstruction off and on the tracks, 

 and, like the other sides, is to be dressed after the ordi- 

 nary manner of aisler causeway. In laying these tracks, 

 all that becomes necessary is to bestow some pains in 

 preparing a firm and compact foundation, the nature 

 of which will in a great measure depend upon the soil. 

 A stratum of stone chips, of the depth of three or more 

 inches, according to the state of the ground, laid in 

 clean sharp sand, will answer in almost every case. It 

 would, in some instances, be of advantage to lay the 

 tracks with runners upon each side as kirb-stones, of 

 about twelve or fourteen inches in length, especially 

 in connexion with the common metalled road. But 

 where ruble causeway is employed for the horse-paths, 

 this precaution is unnecessary. In upholding roads 

 of this description, the intermediate spaces will seldom 

 require repair ; and we have seen, in the example of 

 Leith Walk, that aisler causeway has continued in good 

 order for about fifteen years, and may last double that 

 period with occasional repairs. Although the traffic of 

 carriages would be greater upon the tracks than on a 

 common road generally, yet it is a curious fact, that 

 however spacious a road may be, carriages go very 

 much in particular lines, one after another, and there- 

 fore the duration of an aisler causeway forms a very 

 good criterion in judging of the comparative economy 

 of the proposed wheel-tracks. 



Smoothness The smoothness of railway travelling has often been 

 and quiet- spoken of as luxurious, while the quietness with fahich 

 ness of the 

 road. 



vehicles glide along suit even the delicate ears of a Roads and 

 Hollander, who, partly from this feeling, is induced to Highways, 

 deprive the heavy loaded carriages and hackney coach- *"""Y""* > 

 es of their wheels, and form sledges, as is the practice 

 in Amsterdam and other large towns of Holland. Till 

 of late years, the thoroughfare into Somerset House, 

 like the whole included area of that elegant suite of 

 buildings, was paved with rough granite stones, and 

 during the sittings of the Royal Society, and other 

 public bodies, which held their meetings in the front 

 row, the members were often disturbed by the noise of 

 the carriages passing under the covered way into the 

 square. This particularly attracted the notice of 

 strangers, and the entrance alluded to has lately been 

 laid with gravel, which, though not so cleanly as the 

 tracks, is nevertheless a great improvement. 



On the score of economy, we may notice that in the Expence of 

 vicinity of Edinburgh, where good road materials of stone- 

 every description may be had at moderate rates, a li- tracks, 

 neal yard of these tracks, forming a road for one car. 

 riage, will cost from seven to nine shillings, according 

 to the weight of the load to be conveyed upon them, 

 and consequently double of these sums for two sets of 

 tracks, to suit carriages travelling in opposite directions. 

 These tracks may be estimated to last about twelve 

 or fifteen years, in the ordinary traffic of a city or public 

 road, in the course of which the metalling of a common 

 road must have required to have been frequently re- 

 newed. Not only, therefore, will the comfort of the 

 traveller be provided for, and the wear and tear of his 

 carriage prevented, but the direct economy in uphold- 

 ing the public roads will, by the adoption of this sys- 

 tem, be secured to an immense extent. An idea of 

 this may be formed from the Reports of the Committee 

 of the House of Commons, which goes the length of 

 stating, that even FIVE MILLIONS Sterling annually 

 may be saved to the public by an improved system of 

 roads. 



Iron railways of the form hitherto in common use Iron 

 have of late been suggested both for travelling at wheel- 

 speed and in the conveyance of all sorts of goods. Mr. t 

 Menteath of Closeburn, a considerable time since, made 

 some progress in showing the application of iron wheel- 

 tracks upon the numerous declivities which are every 

 where met with upon the common road. This idea has 

 also been acted upon by Mr. Baird of the Shotts Iron- 

 works, which are situated on the side of a dell, in the 

 bottom of which his foundery is built. In order to 

 give greater facility in bringing up weighty articles 

 from the works, Mr. Baird laid a very complete set 

 of cast-iron tracks, applicable to the traffic of com- 

 mon carts, which admitted of the same load up-hill 

 as in ordinary cases could be drawn upon a level 

 road; a model of these tracks has been lodged in 

 the chambers of the Highland Society of Scotland ; 

 they measure one foot in breadth, an inch and a half 

 in thickness, and are fixed into the check of a cast-iron 

 sleeper or bed, laid across the road in such a manner 

 that they are neither apt to slip aside, to rise perpendicu- 

 larly, nor to be sunk below their proper level ; being 

 nearly flat at the top, they admit of the wheels of a car- 

 riage getting off and on them at pleasure. The expence 

 per lineal yard is understood to be about L.I, 5s. A 

 rail-road of this kind was, in the year 1816, laid for the 

 Forth and Clyde Canal Company, upon an acclivity 

 leading to Port Dundas, near Glasgow, at the rate of 



