called, grouting the joints with lime-water, which finds its way into the gravel between and under the stones, and forms the whole into a solid concreted mass. The purpose served by the lime might also be effectually answered by mixing a little of the borings or chippings of iron, or small scraps of iron hoop, with the gravel used in filling up the joints of the paving. The water would very soon create, an oxide of iron, and form the gravel into a species of rock. I have seen a piece of rusty hoop taken from under water, to which the gravel had so connected itself, for four or five inches round the hoop, as not to be separated without a smart blow of a hammer. And the cast-iron pipes which are laid in moist gravel soon exhibit the same tendency.
It has occurred to me, as I stated to the chairman of this honourable Committee some weeks since, that considerable improvement would be found from paving the sides of a road, upon which the heavy traffic is great, in both directions, and leaving the middle for light carriages, the carmen walking upon the footpaths or sides of the road, would then be close to their horses, without interrupting, or being in danger of accidents from light carriages, which is the case when they are driving upon the middle of the road; and the unpaved part being in the middle or highest part of the road, would be more easily kept in good repair. I have prepared a section of a road formed in this way (No. 3 in the plan), but unless the heavy traffic in both directions is great, one width (say ten or twelve feet, if very well paved,) will be found sufficient; and in this case, I think the paving ought to be in the middle of the road. The width of many of the present roads is, besides, such, that ten or twelve feet can be spared for paving, while twice that width would leave too little for the gravelled part. Although the first cost of paving is so great, I do not think that any other plan can
