paving stones, or any kind of coarse stone; and this should be laid on a bed of broken stones. This mode of paving is in use in Paris. In the autumn of 1835, for instance, the old pavement of the Rue Dauphine was taken up, and relaid on a bed of gravel, to form the foundation for the new pavement. This practice has proved completely successful. In streets where the traffic is not very great, the foundation should be made in the following manner:-a bed should be formed with a convexity of two inches to ten feet, so as to admit of twelve inches of broken stones being laid upon it. These should be put on in layers of four inches at a time. After the first layer is put on, the street should be kept open for carriages to pass over it. When this first layer has become firm and consolidated, then another layer of four inches should be put on, and worked in as before, care being taken to rake the ruts and tracks of the wheels of carriages, so that the surface may become smooth, and consolidated. The same process should be repeated with the third layer of stones, by which means a solid and firm foundation will be established, of twelve inches in thickness, for the dressed paving stones to lie upon.*

Mr. Edgeworth says, in his Essay on Roads, " In all pavements, the first thing to be attended to is the foundation. This must be made of strong and uniform materials, well rammed together, and accurately formed to correspond with the figure of the superincumbent pavement. This has nowhere been more effectually accomplished than in some lately made pavement in Dublin. Major Taylor, who is at the head of the paving board,

After this operation is accomplished, the next thing to be attended to is to provide proper paving-stones. These should be cut into a rectangular shape, and of the hardest quality that can be procured: granite is the best, but whinstone, some descriptions of limestone, and freestone, will answer the purpose.

With regard to the size of the stones, that should be regulated by the intercourse. The streets should be divided into three classes, according as the thoroughfare is greater or less. For streets of the first class, or greatest thoroughfare, the stones should be ten inches in depth, from ten to fifteen inches in length, and from six to eight inches in breadth on the face. For streets of the second class, the stones should be eight inches in depth, from eight to twelve inches in length, and from five to seven inches in breadth on the face. streets of the third class, the stones should be six inches in depth, from six to ten inches in length, and from four to six inches in breadth on the face.

For

After having prepared a proper bottoming, the greatest care must then be bestowed in setting the stones. Fine gravel must be provided, cleansed

before he began to pave a street, first made a good gravel road, and left it to be beaten down by carriages for several months: it then became a fit foundation for a good pavement." Page 33.

* "In France, pavements are made with stones cut with the hammer, of seven or eight inches on every side, like so many dice."- Encyclopédie de l'Ingénieur, vol. i. p. 355.

from all earth, to form a bed over the bottoming of two inches thick for the stones to be set in. Strong mortar must also be provided; and, besides the common tools, each pavior should have a wooden maul, the head of which should be made of beech or elm, and should weigh about fourteen pounds. The stones should be selected so that they may be laid in even courses, and so as to match, as nearly as possible, in each course with regard to breadth and depth.

The pavior should first set a stone on the gravel bed, by striking it strongly downwards with the maul, and then on its sides. Then he should lift it out of its berth, and put mortar on the sides of the two adjoining stones; after which he should again place the stone in its berth, and strike it as hard as he can, downwards and sideways, with the maul, till it is fastended in the position in which it is to remain. Each stone should be set in this manner; and, when the pavement is finished, it will be so firm as not to require ramming.*

The crossings for foot-passengers should be raised above the level of the pavement, by giving a moderate convexity to the bottoming. They should be made with stones of the size for streets of the first class, more accurately dressed.

The pavement should be formed with a regular, but very moderate, convex surface, by giving the bed for it the convexity already mentioned: there

* See Mr. Telford's Report on Pavements, in the Appendix, No. 2., and Mr. James Walker's observations on the same subject, Appendix, No. 3.

should be no gutter or other channel but that which will be formed by the angle made by the surface of the pavement abutting on the curbstone. The curb-stone of the pavement should be made of long blocks of stone, of a quality sufficiently hard to resist the shocks of wheels striking it. These blocks should be bedded in gravel, and joined with cement: they should be sunk four inches at least into the ground, and should be six inches above the pavement.

The foot pavements should be made of welldressed flags; each flag to have its sides rectangular, and to be set in mortar with a very close joint upon a strong gravel bed of six inches in depth. The flagstones should be at least two inches and a half thick: the surface of the foot pavements should have a declivity at the rate of one inch in ten feet towards the street.

In those towns where the intercourse of footpassengers is considerable, the greatest possible breadth should be given to the foot pavements. In general, this important accommodation is too much neglected.

In making a contract for paving a street, it should be so arranged that the work shall be paid for by the superficial yard. A specification should be connected with the contract, requiring that the natural soil shall be removed to a certain depth, and made level; that the bottoming shall consist of certain prescribed materials, and of a fixed depth and convexity, and be laid on in the manner already described; that the stones shall be of a

certain shape, and size, and weight, in each superficial yard; and that they shall be set in a regular

manner.

The specification should also provide that an inspector shall be appointed to see that the conditions of the contract are fulfilled.

A drawing of the transverse section of the proposed pavement should be made, and attached to the contract. (See Plate III., Fig. 1.) But, besides these precautions, the persons who have the management of the business of making the contract should take care to ascertain the sum for which an honest and skilful contractor can execute the work in a proper manner. This is necessary in order that they may avoid making a bargain on such terms as will oblige the contractor to have recourse to inferior materials and workmanship to save himself from losing money by his undertaking. It is not, by any means, difficult to ascertain exactly what each part of this kind of work will cost, and to make an accurate estimate of the total expense to be incurred.

Such an estimate ought always to be made by a competent person in the employment of the commissioners or other persons who have to manage contracts for pavements. And in place of promoting an indiscriminate competition for the purpose of lowering the price, without regard to the quality of the work to be performed, the commissioners or other managers ought to call upon a few of the most respectable paving contractors for proposals; and give the contract to the bidder who