First lay all small poles or brush transversely and across the road. Next take long trees-the smallest ends being at least 10 inches diameter-and place them longitudinally across the poles, in two rows, 8 feet apart from centre to centre, making the ends at the junction of each piece lap each other at least 3 feet, breaking joint on either side, and placing upon these ends large logs of sufficient length to extend across the road, and 2 feet on each side of these stringers. Cover the stringers with transverse logs, 12 feet long from scarf to scarf, and at least 10 inches in diameter at the smallest end, fitted close together on the straight portions; the logs alternated with a large and small end, and on the outer side of curves, all the large ends, which will assist in the curvature of the road and the gravity of the vehicles. Next, adze off the centre ridges of these logs to a face of about 5 inches, for a width of 9 feet in the centre of the roadway, and cover this 9 feet with gravel, to fill in between the logs, and give a smooth surface. A good plan is to lay on the top of the road thus formed poles of 5 or 6 inches in diameter, spiked down on each side of the track, every 10 feet, with oak pins, to prevent, in frosty weather, the lateral sliding of wagons.

Roofing, Pasteboard and asphalt -This material is most suitable for flat roofs, having a fall of 1-1/2 inches to 4 inches per running foot. It may, however, also be used for roofs having a greater fall, the expense being in this case somewhat larger tlian lor flat roofs, as the laying on is more difficult. Cover the roof first with dry boards, 3/4 inch to 1 inch thick, and not above 6 inches broad; if more than the last-named width, or if not sufficiently dry, the boards ought to be split once before being laid on, in order to keep them from warping, and every board should be fastened with three nails at least on each of the rafters. The boards do not require to be rabbeted; only those ends of the boards which form the eaves, by extending beyond the wall need to be joined in the said manner. In case of boards 3/4 inch thick being applied, the rafters should not be more than 2 feet from each other, as the boards may be too elastic and not strong enough to support the weight of the workmen, while the roof will not be perfectly substantial.

The roofing may be done either from gable to gable, or from the eaves to the foot-ridge, the first roll being laid with a bend of 1 inch beyond the roof, and fastened with the flat-headed iron wire nails supplied for that purpose. The second roll is laid 1-1/2 inches over the first, and so on till the roof is covered. The joints and heads of the nails are then coated with asphalt mastic, and the seams thus coated are strewed with dry sand. The whole roof is then coated with the mastic, and covered with sand. This coating, which is only to be effected in dry weather, renders the roof perfectly water-tight, and it can then, if desired, be painted or whitewashed. A hundredweight of mastic covers a surface of 65 square yards. This process is in use in Copenhagen, Denmark, and the roof weighs about 1/3 the weight of a tiled roof, and is substantial, resisting alike the influence of water, fire, heat, and cold.