of the stream, which is the view given in our engraving, you have the magnificent Friburg Alps behind you. On the left you look up the valley of the Sarine, toward the mountains situated at the bottom of the lake of Geneva with the points of the higher Alps overtopping them, clad with eternal snow. Before you is the view down the valley, with the suspension bridge across it, as is represented in our engraving. The hills receding in the background toward the Jura, finish the splendid

panorama.

The road from Berne crosses this valley at the entrance of Friburg. It descends from the heights opposite the town, and now enters the city over the suspension bridge. But the old road, which remains for the use of the inhabitants in its line, descends steeply into the bottom of the valley, winds along the banks of the river, and passing the spot from which the view is taken, it crosses the river three times over wooden bridges before it reaches the gate at the south side of the city. Thence the ascent to the upper part, where the cathedral and principal inns are situated, is by extremely steep streets, rising obliquely upward, and built one above the other; so that, in one place, the upper street is carried on stone arches over the roofs of the houses in the street below. Those who recollect the old town of Edinburgh will readily understand this. The distance saved by the new bridge is more than two miles, but this is a trifling advantage compared to the fatigue saved both to travellers and horses, in the steep and dangerous ascent from the lower gate to the upper part of the town.

The first view of the bridge from a distance is very striking; the cables on which it is suspended are scarcely visible, and it looks like a tight rope or long plank stretched across the valley. The porticoes, or piers of solid masonry, stand on each side, through which is the entrance to the bridge. They are built in the Doric style, and are seventy-five feet high from the foundation on the rock, and rise sixty feet above the level of the bridge. The width of them is forty-two feet, and the depth eighteen. On the tops of these piers are iron friction-rollers, over which the suspension cables pass, which are firmly attached to the solid rock on each side, at the distance of one hundred and sixty feet from them. The road turns under the cables before it passes through the piers to go on the bridge. This was unavoidable at the northeast entrance, on account of the steep rising of the hill; and on the southwest, or city side, the street to which it leads runs parallel to the river, and consequently at right angles to the bridge. A new approach in a straight line will probably be open in time; but at present the buildings which are in the way would have required a great sum of money to purchase them, and the available funds are not sufficient. The foundation of the piers are on a hard and solid rock, and placed (for greater security) at the distance of thirty feet from the edge of the precipice. A small semi-circular terrace intervenes between each of the piers and the bridge, which add much to the elegance of the whole appearance, and afford room for the toll-houses. The view from them is most beautiful up and down the valley, and toward the Alps. A section of these terraces is represented in fig. 2, page 513. A is the foundation of the pier ; B, B, B, the rock; C, the terrace; D, a stone wall to keep up the earth and stones by which the terrace is formed. In fig. 3, are represented Fig. 3.

the friction-rollers over which the cables pass. These rollers are of cast-iron, and each supported on a massy block of Jura limestone, which is nearly as hard as granite. The whole pier is built of the same materials. All the blocks fit most accurately, and are hewn with fair faces and well squared. They are fastened together with iron bolts and straps, and every interstice between them is filled up with a strong mortar poured on in a liquid state; so that the whole forms nearly a

solid mass like a rock. The iron used in this part, which amounts to upward of twelve tons, came from England by Genoa, was carried over the Alps by the Simplon, and by very steep roads to Friburg. Notwithstanding the expense of the carriage, it cost twenty per cent. less than iron which is manufactured within thirty miles of the spot could have been procured. Fig. 4 gives a transverse section of the bridge as you enter from the terrace.

Fig. 4.

The whole bridge is supported or hung on four wire cables, which are suspended in pairs from pier to pier, forming a curve, of which the chord is eight hundred and seventy feet, and the perpendicular bend in the middle is fifty-five, where they come down within a foot of the road. This road, twenty-two feet broad, is formed of firplanks, resting on rafters, which are again supported by beams projecting on each side of the bridge, where they rest in strong iron stirrups (fig. 5, A). A raised path for foot-passengers, three feet wide, runs on each side. The hook at the upper part of the stirrup (a a) is passed into the loop of a cord or wire, at the upper end of which is fixed a double hook (B), embracing two of the cables, of which the section is seen at b b. Thus the beams are suspended at both ends from the cables. They are one hundred and sixty-three in number, and at the distance of between four and five feet from each other. The rafters, on which the planks of the road are strongly fixed, lie across the beams, and are firmly bolted to them, which gives the whole road a considerable degree of stiffness. This is increased by an oaken railing, or parapet, formed of a succession of St. Andrew's crosses, surmounted by a strong toprail. The railing is rather massy compared to the rest of the bridge; but it gives greater solidity, and serves to prevent the fears which a slight railing might have excited in those who traverse the bridge on foot at so great a height. The top of the steeple of a church built in the valley is looked down upon as an inferior object. The cords by which the beams are suspended from the cables are each composed of thirty wires, about one twelfth of an inch in diameter; and as each of these can support, without breaking, a weight of twelve hundred pounds, and there are one hundred and sixty-three pairs of them, they can sustain a weight of upward of five thousand tons, equally distributed over the road, including the weight of the road itself.

The cables, which we shall now more minutely describe, are composed of similar wires formed into fifteen bundles of eighty wires each, they are not twisted like the strands of a hempen cable, but each wire goes straight from end to end; and the whole fifteen bundles are firmly tied into a cylindrical form by means of annealed wire wound round the whole, at intervals of two or three feet. Two such cables are placed close together on each side, and pass over the friction rollers on the piers described before. There is a distance of nearly thirty feet between the two pairs of cables, and as the stirrups are only twenty-four feet from each other across the bridge, the suspending cords converge as they descend to the road; this adds to the steadiness of the bridge.

To prevent the wearing out of the cables by the rollers, and to divide the pressure upon them more equally, the fifteen bundles are not tied into a round form at the place where they go over the rollers, but are flatted out, and form a strap a few feet long. They are then again united in the form of a cable till they reach the place where they are fixed to the rock. The manner in which the ends are secured is ingenious and worthy of description. An oblique tunnel is excavated in the rock in the direction in which the cables descend from the piers, to the depth of forty-five

feet from the level of the road on the city side, and twice that depth on the other. At the end of this a vertical pit or well is made in the solid rock, to the depth of forty-five feet, with the sides cut into bevelled cavities (see fig. 6). A is the oblique tunnel; B B the vertical well; CCC the cavities in the side of it. In this well are pillars of masonry, the blocks of which are so arranged as to fit the cavities and resist any pressure upward. Through the centre of each pillar is a small cylindrical bore, which admits of a cable of half the size of the main cable. At the bottom is a very large block with a hole bored through the centre; the cable is passed through it, and fixed round a very strong piece of iron, which forms the anchor and bears the whole strain. Each main cable is attached to two others, which, passing down the oblique tunnels and over friction-rollers at the entrance of the well, are secured at the bottom in the manner described. There are consequently eight such fastenings at each end, which bear the enormous strain of the cables. Room is left to admit of the lower parts being occasionally inspected.

The cables were raised from pier to pier without much trouble, each of the fifteen bundles being raised separately, and then the whole firmly connected. The descending cords were then hooked on, the stirrups affixed, and the beams put through them. In this manner the road was carried forward rapidly and the bridge completed. The length of the cords was so adjusted that the bridge rises a few feet in the middle, which tends to prevent too great vibration. Here the hooks, which embrace the cables on each side, and the stirrups, which hold the ends of the beams, touch each other. The cords are gradually longer toward each pier till they are equal to the height of the piers at each end.

Great pains have been taken to have every wire stretched equally, and the whole firmly bound together. They are separately painted and varnished, and the whole cable is painted white, in order to make the least appearance of rust conspicuous.

The work, after some interruption, was begun in the spring of 1832, and the bridge was completed and opened to the public on the 23d of August, 1834. No serious accident occurred, nor was there a single life lost, which is reflected on with peculiar satisfaction by the engineer and architect, M. Challey.

We shall conclude this account with a short history of the construction of this bold specimen of modern art. Many ingeniously-constructed wooden bridges are to be found in all parts of Switzerland; and that over the Rhine at Shaffhausen, which was destroyed in the late war, has been celebrated for the boldness of the span, which was three hundred and sixty feet. The idea of a bridge over the valley of the Sarine at Friburg was more than once entertained, and proposals and plans were made; but the required height of the piers, and the danger from gusts of wind to a bridge so exposed, and which, if roofed in, as is the case with most of the Swiss wooden bridges, and essential to their duration, would present too great a surface to the storm, appeared insurmountable obstacles. When suspension bridges became more generally known, the idea of a bridge revived; but all calculations of the expense of the common iron chains, or rods of suspension, where iron is so dear, deterred any one from undertaking it. The same difficulty had led to the substitution of wire, of which a small foot-bridge was constructed in 1823 over the Fossi at Geneva ; and in 1825, M. Seguin constructed a larger bridge of wire over the Rhone. On the plan of these M. Challey, a French engineer, who in partnership with M. Sequin, junior, had built a wire bridge over the Rhone at Beaucaire in 1829, proposed to erect one at Friburg, and, after some negotiation, he contracted for it on the following conditions:

1. The ground for the works to be provided, and the approaches made for him; 2. Three hundred thousand francs (sixty thousand dollars) to be paid him as the works proceeded; and

3. The receipt of all the tolls for forty years from the opening of the bridge. In consideration of this, M. Challey engaged to finish the bridge, according to the plans agreed upon, at his own cost and risk, having the option of constructing it with two spans or only one-to keep it in repair for forty years, at his own cost.

The option of a bridge with two spans was inserted, to satisfy some of the parties, who had a prejudice against so great a span as impracticable; but M. Challey never for a moment entertained any other idea than that of a single bridge. The pier, which must have been built in the middle, must have been upward of two hundred feet high, and have had a very deep foundation: the expense of it would have been enormous, and the effect far inferior. The whole bridge, as it now stands, cost M.