Imagens das páginas
PDF
ePub

not less than 7 lbs. to the superficial foot. All door frames, window frames, skirtings, angle beads, fascia, and all wood and iron work whatever, to be painted three coats in oil; the doors and skirtings to be finished an oak colour. The windows to have small diamond glass, in lead and iron casements."

Ironmongery.

"There are to be iron frames for lead lights for all the windows; the middle to be an opening casement, with proper hinges and fastenings. The front and back doors to be hung with four-inch best buts, and each to have a strong rim lock, and two bright bolts; all the inner doors to be hung with three inches and a half buts, and each to have a strong rim lock.

"Plain square grates to be fixed in each of the fireplaces."

Miscellaneous Matters.

"All the fireplaces to have neat, plain, square stone jambs, lintels, and mantels.

"A toll board to be made and painted with the rates of tolls, and fixed up where directed by the engineer.

"The contractor to find all materials and labour, and finish the whole to the satisfaction of the before-mentioned engineer, on or before the day of

TOLL-GATES AND BARS.

A toll-gate should never be placed on a hill or at the bottom of one. When going up hill, the horses must make a great exertion to put a carriage in motion after being stopped at a toll-gate. Many fatal accidents have occurred from having toll-gates just at the bottom of hills.

When circumstances render it unavoidable that a toll-gate should be placed at the bottom of a hill, the gateway should be very wide. If a single gate be used, it should not be less than fifteen feet in the clear: but, in such a situation, it is much better to make double gates, meeting in the middle, without a centre post; by these means an opening may easily be had of from twenty-four to thirty feet in the clear.

Toll-gates should be painted white, to make them more easily seen in the night-time. They are frequently made too high. When this is the case, they are expensive and unsightly, and their additional weight acts as a powerful leverage in straining and pulling the hanging post out of its place.

The toll-gates erected by the parliamentary commissioners at South Mims, and on the Coventry road, are only four feet six inches high: they open to sixteen feet in the clear (Plate V. fig. 2.); they are hung on posts made of the best oak, sunk five feet in the ground, and secured by brickwork and struts; there are also two bars passing diagonally from post to post, by which means they are firmly braced together.

These gates are hung on Collinge's patent hinges, which are particularly fit for this purpose; they run about five feet along the upper and under rail of the gate, and are connected by a diagonal piece of metal, carried from the bed of the lower hinge to the point of the upper one, in order to prevent the gate from sinking. The balls of the hinges are cast with the caps and plinths of the posts, so that the posts are not weakened by holes or mortices, as in the usual manner of hanging gates. The caps and plinths of metal are also a great security to the posts, by preserving them from the effects of the weather, and by preventing the wheels of carriages from chafing their angles.

Flapping posts are set in the ground at proper places, to prevent the gates from opening too far, and straining the hinges; these posts are about two feet and a half above the ground, and two feet in it. Catches or clicks are let into these posts, to hold the gates open when thrown back; these catches project about two inches from the side of the posts, and turn on a pin within the post, the inner end of the catch being made heavier than the outer, and always throws that end up, and by that means it takes hold of the bottom of the lower bar of the gate, by a notch cut in it for that purpose: by making the catches in this way, they are out of the reach of injury. In the common way they are put on the top of the posts, from which they project six or seven inches; in consequence of which they are frequently torn off by wheels of carriages and waggons.

LAMPS.

All toll-gates should be well lit; and for this purpose nothing is better than a lamp made similar to the best coach lamp, with powerful reflectors, and large air holes. These lamps are found to be economical, and to answer every purpose; they should be about ten inches high, and seven inches square in the clear; they cost about 17. 7s. each.

MILESTONES.

Milestones are convenient and agreeable to travellers, and useful in enabling coachmen to keep their time with accuracy. They are also serviceable in assisting road surveyors in laying out and measuring work. They should be made of very hard stone of a light colour, and should be much larger than they usually are, in order that they may be readily seen, and have space enough for large figures; for if they are not large it is difficult when going fast to read them. A drawing of a proper shaped milestone is given in Plate V. Fig. 4.

The figures XIV. in this drawing show the distance from London, but though large, they are not large enough, and therefore it would be better on all main roads from London to have on the plate only the distance from London, in the largest figures the plate will admit of.

206

CHAPTER VIII.

MANAGEMENT OF ROAD WORKS.

WHEN a new road is to be made, as soon as the precise line of it is finally determined upon, the following circumstances should be particularly attended to.

I. Drawings should be made to show, 1st, the natural surface of the ground; 2ndly, the longitudinal inclinations of the proposed road; 3dly, the slopes of the cuttings and embankments; 4thly, the form of the bed of the road and footpath; and, 5thly, the courses of materials to be laid on, and the thickness of each course.

Drawings should also be made, describing the plans of the bridges, culverts, cross drains, inlets, outlets, depôts, and fences which are required to be made.

II. A specification should be prepared, to explain in detail the precise method of executing every part of the work.

III. After the specification has been settled, an estimate should be made of the expense to be incurred.

The following is the estimate for making part of the Holyhead Road, near Coventry:

« AnteriorContinuar »