DRIVES, AVENUES, AND SERVICE ROADS. 



method will be best, but where it is expensive or difficult to obtain, the latter is the 

 more economical, particularly as it allows of a saving in the subsequent operations. 

 Peaty The success of the pitching depends almost entirely on getting a good firm bottom 



subsoils. on which to put it. In most districts this is easily obtained by removing a foot or 



so of turf, soil, fibrous matter, etc., from the site, but in others, where the ground is 

 very wet and peaty, or where, as in many parts of Sussex, the subsoil is pure light sand, 

 means must be taken to insure that it will not work up between the pitching and so 

 destroy the work, as it otherwise would in the course of a few weeks, through the agency 

 of wheeled traffic, if means were not taken to prevent this. In the case of a peaty 

 subsoil, where this is only shallow, by far the cheapest method is to remove it entirely 

 and fill up with dry, clean rubbish, adding a proper system of land drains, even though 

 this may mean a rather heavy initial expense. Where the peat is too deep for this, 

 it must be thoroughly drained, and both here and in the case of light sand, a layer of 

 brushwood, broom, or other tough fibre, laid under the pitching, will keep everything 

 in place, until time and the hammering of the traffic have together thoroughly consolidated 

 the whole construction. In some districts, such as North Hertfordshire, pitching of any 

 sort is dispensed with, and a layer of chalk substituted, but this is a material which 

 needs very careful using, for in other districts where its physical properties are not quite 

 the same, a sticky, putty-like substance would ooze up between the stones and ruin the 

 whole. Brick bats and old building rubbish, if clean, make good pitching where stone 

 is not available, and the writer has made good public park roads with a foundation of 

 the broken crockery, etc., from the works in the Pottery Districts. It will thus be 

 seen that in drive formation there is scope for much ingenuity combined with a 

 knowledge of local conditions. 



The pitching having been laid, a solid foundation is formed on which to put the 

 surface material of the drive. This is usually of two kinds, which may be described 

 as the sub-surface material and the grouting. The former consists of stone broken to 

 pass through a sieve with a two-inch mesh, and the latter is either finely-broken stone 

 used to fill in between the sub-surface material and form a smooth surface, or it is 

 material added to cement the whole together. Undoubtedly the best materials are those 

 which make their own grout, that is to say those of a tough but not brittle consistency 

 which, when rolled, make a cement-like detritus which itself acts as a grout. The best 

 of these is the magnesian lime-stone so largely used throughout the Lake District, but 

 all lime-stones are by no means so good. Some make the dustiest and muddiest roads 

 in the kingdom. Such materials as granite or flints need an added grout, and probably 

 the best in most cases is formed of road scrapings, while another often used is composed 

 of garden loam. If the sub-surface material is formed from rounded stones from a 

 watercourse or sea shore, they must each be broken at least once, even if this makes 

 them rather too small, otherwise the whole will not bind together into a solid mass and 

 horses' feet will be continually loosening rounded pieces of material. Where a drive 

 is being made to lead to a new house, it is a good plan to make it up roughly before 

 building operations commence, and then to insert a clause in the main contract, making 

 the contractor responsible for its being left by him in as good a condition as he finds it. 

 This means that all the heavy carting materials for the house will be done over it, and 

 thus it will be thoroughly consolidated and any weak points will show themselves, and be 

 filled in with building rubbish, often several times, until they are made good and solid. 

 When the heavy carting is finished, a most exceptionally good sound foundation for the 

 drive will remain, which will only need the surface repairing. 



Rolling. At every stage in its construction, the drive should be rolled with a fairly heavy 



roller, the weight of which will depend on the amount of pounding the material will 

 stand, without either breaking up or being driven into the subsoil, and, in the case of a 



Sub-surface 

 material. 



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