In preparing another edition of the various papers on roads, which I have published during the last six years, it may be useful to take a slight review of the subject, and of the gradual progress of road improvement throughout the country. That any further information should be called for, after the numerous additions made to the original pamphlet, (particularly the last communication to the Board of Agriculture,) is a convincing proof of the impossibility of conveying adequate instructions for practical purposes, by means of the press. It is, however, of the utmost importance that the _theory_ be fully understood, as from want of comprehending the original nature of the system have arisen the many fruitless attempts at imitation, which have cost such vast sums to the public. The practical utility of some parts of the system is so obvious, that they have been acted upon in various places, without any desire of further improvement. It is uncommon now, to meet with roads repaired with large stones, or of the dangerous convex form, which was the universal custom about five years ago; but these improvements being merely grafted on the old erroneous method, have never been attended with the rapid diminution of expense, and the durable advantages which immediately result from the adoption of the entire system as recommended by me. Those who continue to use any part of the old method of road-making, are not, perhaps, aware of the principles upon which they are acting. I have formerly remarked, that the old roads of the country were generally carried along the tops of hills in search of dry or strong ground; and it is plain that the first turnpike roads were merely attempts to open more direct communications through the country, in continuing, by mechanical means, the rocky paths, to which travellers were obliged to resort. With this view, large masses of stone were first sunk into the ground, and afterwards thick layers of broken stone strewed over them, so as, in fact, to form an artificial rock. The insecurity of this unskilful structure must be obvious. The rain penetrating through every part of the surface kept it continually in a loose state, and as it was imbedded _below_ the _ground_ water, it was constantly broken up in winter by the frost. Hence the vast sums required for the forming new roads, and the heavy and incessant expense of keeping them in a passable state. Any improvements that have been made on this plan, merely relate to the smoothness of the surface, by more carefully laying on the stones, at, consequently, a greater expense: but the original principle remains the same in every road, except those where the new system has been fully adopted. Under such disadvantages, it is not surprizing that the roads of the kingdom have not kept pace with the advancement of every other useful art. The large sums demanded for the first outlay, and the frequent failure of such speculations from the badness of the