Scrambles amongst the Alps/Chapter 3

by Edward Whymper

CROSSING MONT CENIS (1861).

CHAPTER III.

THE MONT CENIS—THE FELL RAILWAY—THE GREAT TUNNEL THROUGH THE ALPS.

Guide-books say that the pass of the Mont Cenis^[1] is dull. It is long, certainly, but it has a fair proportion of picturesque points, and it is not easy to see how it can be dull to those who have eyes. In the days when it was a rude mountain-track, crossed by trains of mules, and when it was better known to smugglers than to tourists, it may have been dull; but when Napoleon's road changed the rough path into one of the finest highways in Europe, mounting in grand curves and by uniform grades, and rendered the trot possible throughout its entire distance, the Mont Cenis became one of the most interesting passes in the Alps. The diligence service which was established was excellent, and there was little or nothing to be gained by travelling in a more expensive manner. The horses were changed as rapidly as on the best lines in the best period of coaching in England, and the diligences themselves were as comfortable as a "milord" could desire. The most exciting portion of the route was undoubtedly that between Lanslebourg and Susa. When the zig-zags began, teams of mules were hooked on, and the driver and his helpers marched by their side with long whips, which they handled skilfully. Passengers dismounted, and stretched their legs by cutting the curves. The pace was slow but steady, and scarcely a halt was made during the rise of 2000 feet. Crack! crack! went the whips as the corners of the zig-zags were turned. Great commotion among the mules! They scrambled and went round with a rush, tossing their heads and making music with their bells. The summit was gained, the mules were detached and trotted back merrily, while we, with fresh horses, were dragged at the gallop over the plain to the other side. The little postilion seated on the leader smacked his whip lustily as he swept round the corners cut through the rock, and threw his head back, as the echoes returned, expectant of smiles and of future centimes.

The air was keen and often chilly, but the summit was soon passed, and one quickly descended to warmth again. Once more there was a change. The horses, reduced in number to three, or perhaps two, were the sturdiest and most sure of foot, and they raced down with the precision of old stagers. Woe to the diligence if they stumbled! So thought the conductor, who screwed down the breaks as the corners were approached. The horses, held well in hand, leant inwards as the top-heavy vehicle, so suddenly checked, heeled almost over; but in another moment the break was released, and again they swept down, urged onwards by whip, "hoi," and "ha" of the driver.

All this is changed. The Victor Emmanuel railway superseded a considerable portion of Napoleon's road, and the "Fell" railway has the rest. In a few years more the great tunnel of the Alps will be completed, and that will bring about another change.

The Fell railway, which has been open about eighteen months, is a line that well deserves attention. Thirty-eight years ago Mr. Charles Vignolles, the eminent engineer, and Mr. Ericsson, patented the idea which is now an accomplished fact on the Mont Cenis. Nothing was done with it until Mr. Fell, the projector of the railway which bears his name, took it up, and to him much credit is due for bringing an admirable principle into operation.

The Fell railway follows the great Cenis road very closely, and diverges from it either to avoid villages or houses, or, as at the summit of the pass on the Italian side, to ease the gradients. The line runs from St. Michel to Susa. The distance between those two places is, as the crow flies, almost exactly equivalent to the distance from London to Chatham; but by reason of the numerous curves and detours the length of the line is nearly brought up to the distance of London from Brighton. From St. Michel to the summit of the pass it rises 4460 feet, or 900 feet more than the highest point of Snowdon is above the level of the sea; and from the summit of the pass to Susa, a distance less than that from London to Kew, it descends no less than 5211 feet!

The railway itself is a marvel. For fifteen miles and three quarters it has steeper gradients than one in fifteen. In some places it is one in twelve and a half! An incline at this angle, starting from the base of the Nelson Column in Trafalgar Square, would reach the top of St. Paul's Cathedral if it were placed at Temple Bar! A straight piece of railway constructed on such a gradient seems to go up a steep hill. One in eighty, or even one in a hundred, produces a very sensible diminution in the pace of a light train drawn by an ordinary locomotive; how then is a train to be taken up an incline that is six times as steep? It is accomplished by means of a third rail placed midway between the two ordinary ones, and elevated above them.^[2]The engines are provided with two pairs of horizontal driving-wheels as well as with the ordinary coupled vertical ones, and the power of the machine is thus enormously increased; the horizontal wheels gripping the centre rail with great tenacity by being brought together, and being almost incapable of slipping, like the ordinary wheels when on even a
THE CENTRE RAIL ON A CURVE.moderate gradient.^[3]

The third rail is the ordinary double-headed rail, and is laid horizontally; it is bolted down to wrought iron chairs, three feet apart, which are fixed by common coach-screws to a longitudinal sleeper, laid upon the usual transverse ones: the sleepers are attached to each other by fang-bolts. The dimensions of the different parts will be seen by reference to the annexed cross section:—

Let us now take a run on the railway, starting from St. Michel. For some distance from that place the gradients are not of an extraordinary character, and a good pace is maintained. The first severe piece is about two miles up, where there is an incline of one in eighteen^[4] for more than half-a-mile;—that is to say, the line rises at one step one hundred and sixty-four feet. From thence to Modane the gradients are again moderate (for the Fell railway) and the distance—about ten miles and a half from St. Michel—is accomplished without difficulty in an hour. Modane station is 1128 feet above St. Michel, so that on this easy portion of the line there is an average rise of 110 feet per mile, which is equal to a gradient of one in forty-eight; an inclination sufficiently steep to bring an ordinary locomotive very nearly to a halt.

Just after passing Modane station there is one of the steepest inclines on the line, and it seems preposterous to suppose that any train could ascend it. A stoppage of ten minutes is made at Modane, and on leaving that station, the train goes off at the hill with a rush. In a few yards its pace is reduced, and it comes down and down to about four miles an hour, which speed is usually maintained until the incline is passed, without a diminution of the steam-pressure. I say usually, because, if it should happen that there is not sufficient steam, or should the driver happen to make a slip, the train would most likely come back to Modane; for, although the break-power on the train is much more than sufficient to prevent it running back, the driver could hardly start with the breaks on, and the train would inevitably run back if they were off.

After this incline is passed, the line mounts by comparatively easy gradients towards Fort Lesseillon; it is then at a great height above the Arc, and as one winds round the faces of the cliff out of which the Napoleon road was cut, looking down upon the foaming stream below, without a suspicion of a parapet between the railway and the edge of the precipice, one naturally thinks about what would happen if the engine should leave the rails. The speed, however, that is kept up at this part is very gentle, and there is probably much less risk of an accident than there was in the days of diligences.

The next remarkable point on this line is at Termignon. The valley turns somewhat abruptly to the east, and the course of the railway is not at first perceived. It makes a great bend to the left, then doubles back, and rises in a little more than a mile no less than three hundred and thirty-four feet. This is, perhaps, the most striking piece of the whole line.

Lanslebourg station, 25½ miles from, and 2220 feet above, St. Michel, is arrived at in two hours and a quarter from the latter place. The engines are now changed. Thus far we have been traversing the easy portion of the route, but here the heavy section begins. From Lanslebourg the line rises continuously to the summit of the Mont Cenis pass, and accomplishes an ascent of 2240 feet in six miles and a third of distance.

It is curious and interesting to watch the ascent of the trains from Lanslebourg. The puffs of steam are seen rising above the trees, sometimes going in one direction, and sometimes directly the contrary, occasionally concealed by the covered ways—for over two miles out of the six the line is enclosed by planked sides and a corrugated iron roof to keep out the snow—and then coming out again into daylight. A halt for water has to be made about half-way up; but the engines are able to start again, and to resume their rate of seven miles an hour, although the gradient is no less than one in fourteen and a half. The zigzags of the old Cenis road are well known as one of the most remarkable pieces of road-engineering in the Alps. The railway follows them, and runs parallel to the road on the outside throughout its entire distance, with the exception of the turns at the corners, where it is carried a little further out, to render the curves less sharp. Nevertheless they are sufficiently sharp (135 feet radius), and would be impracticable without the centre rail.

The run across the top of the pass, from the Summit station to the Grande Croix station—a distance of about five miles—is soon accomplished, and then the tremendous descent to Susa is commenced. This, as seen from the engine, is little less than terrific. A large part of this section is covered in,^[5] and the curves succeed one another in a manner unknown on any other line. From the outside the line looks more like a monstrous serpent than a railway.

THE COVERED WAYS ON THE "FELL" RAILWAY (ITALIAN SIDE OF THE MONT CENIS).

Inside one can see but a few yards ahead, the curves are so sharp, and the rails are nearly invisible. The engine vibrates, oscillates, and bounds; it is a matter of difficulty to hold on. Then, on emerging into the open air, one looks down some three or four thousand feet of precipice and steep mountain-side. The next moment the engine turns suddenly to the left, and driver and stoker have to grip firmly to avoid being left behind; the next, it turns as suddenly to the right; the next there is an accession or diminution of speed, from a change in the gradient. An ordinary engine, moving at fifty miles an hour, with a train behind it, is not usually very steady, but its motion is a trifle compared with that of a Fell engine when running down hill.

THE MONT CENIS ROAD AND THE FELL RAILWAY, NEAR THE SUMMIT OF THE PASS, ON THE ITALIAN SIDE.

It may be supposed from this that travelling over the Fell railway is disagreeable rather than pleasant. It is not so; the train is steady enough, and the carriages have remarkably little motion. outside they resemble the cars on the Swiss and American lines; they are entered at the end, and the seats are arranged omnibus-fashion, down the length of the carriage. Each carriage has a guard and two breaks,—an ordinary one, and a centre rail break; the handles of these come close together to the platform at one end, and are easily worked by one man. The steadiness of the train is chiefly due to these centre rail breaks. The flat face A, and the
CENTRE RAIL BREAK.corresponding one on the opposite side, are brought together against the two sides of the centre rail by the shaft B being turned, and they hold it as in a vice. This greatly diminishes the up-and-down motion, and renders oscillation almost impossible. The steadiness of the train is still further maintained by pairs of flanged guide-wheels under each of the carriages, which, on a straight piece of line, barely touch the centre rail, but press upon it directly there is the least deviation towards either side.^[6] There is no occasion to use the other breaks when the centre rail breaks are on; the wheels of the carriages are not stopped, but revolve freely, and consequently do not suffer the deterioration which would otherwise result.

The steam is shut off, and the breaks are applied, a very few minutes after beginning the descent to Susa. The train might then run down for the entire distance by its own weight. In practice, it is difficult to apply the proper amount of retardation; the breaks have frequently to be whistled off, and sometimes it is necessary to steam down against them. Theoretically, this ought not of course to occur; it only happens occasionally, and ordinarily the train goes down with the steam shut off, and with the centre rail breaks screwed up moderately. When an average train—that is, two or three carriages and a luggage-van—is running down at the maximum speed allowed (fifteen miles an hour), the breaks can pull it up dead within seventy yards. The pace is properly kept down to a low point in descending, and doing so, combined with the knowledge that the break-power can easily lessen it, will tend to make the public look favourably on what might otherwise be considered a dangerous innovation. The engines also are provided with the centre rail break, on a pattern somewhat different from those on the carriages, and the flat sides which press against the rails are renewed every journey. It is highly desirable that they should be, for a single run from Lanslebourg to Susa grinds a groove into them about three-eighths of an inch in depth.

Driving the trains over the summit section requires the most constant attention, and no small amount of nerve, and the drivers, who are all English, have well earned their money at the end of their run. Their opinion of the line was concisely and forcibly expressed to me by one of them in last August. "Yes, mister, they told us as how the line was very steep, but they didn't say that the engine would be on one curve, when the fourgon was on another, and the carriages was on a third. Them gradients, too, mister, they says they are one in twelve, but I think they are one in ten, at the least, and they didn't say as how we was to come down them in that snakewise fashion. It's worse than the G. I. P.,^[7] mister; there a fellow could jump off; but here, in them covered ways, there ain't no place to jump to."

The Fell railway is of the nature of an experimental line, and as such it is a success. It has reduced the time that was formerly occupied in passing from St. Michel to Susa by nearly one-half;^[8] it has lessened the cost and increased the comfort to the passengers. The gauge (3 feet 7⅜ inches) is a mistake, inasmuch as it loses time and causes trouble by the transference of the passengers, limits the power of the engines, and renders the rolling stock unfit for general use, should the line be pulled up,—which, according to the terms of the concession which was granted to the promoters, is to be done when the great tunnel of the Alps is open for traffic.

The covered ways have been made too low, and the steam and smoke are driven down by the roof in an unpleasant manner.^[9] If, however, the doors of the carriages are shut, but little inconvenience is experienced on this account.

The engines are not anchored as firmly to the line as the carriages, and their motions are very violent. There is, too, a certain vibration in the working parts of their machinery, which indicates that they are not perfect. In ordinary locomotives the oscillatory movements which are acquired (even at moderate speeds) from the inequalities of the road, are less likely to cause injury to the machinery than the same motion is to the locomotives on the Fell railway. With the former a certain amount of lateral play is possible over the base of the engine, but in the latter case it is impossible when the horizontal wheels and breaks are gripping the centre rail. Many of the working parts of these locomotives must be subjected to sudden and violent strains, which do not occur to others on ordinary lines.

The engines are admitted to be imperfect, and new ones are in course of construction. It is to be regretted there is a probability that the line will be pulled up at no very distant date,' as improvements are thus prevented from being carried out; otherwise there would be no doubt it might become a thoroughly practical and profitable one. Let us now turn to the great tunnel of the Alps, the completion of which is to be death to the Fell railway.

When M. Medail of Bardonnêche—thirty years ago—pointed out that a shorter tunnel could be constructed beneath the Alps between his village and Modane than at any other place in the Sardinian States having a similar elevation above the level of the sea, neither he, nor any other person, had the least idea how the project could be executed.

The first step was taken by the geologists Signor Sismonda and M. Elie de Beaumont. They pointed out, about twenty years ago, that calcareous schists and quartzite rocks would form a large proportion of the strata through which the tunnel would pass. It takes a miner one hour and a half to two hours to make an ordinary hole for blasting (28 inches deep) in the calcareous schist, and not less than eight hours to make one 20 inches deep in the quartzite.^[10] When would the tunnel have been finished if the ordinary processes had been alone employed?

The ordinary processes were clearly unavailable. The tunnel would be not only of prodigious length,^[11] but it would have to be constructed without shafts. At no place where a shaft would have been of any use would it have been possible to make one less than 1000 feet deep! If one had been made about midway between the two ends, it would have been no less than 5315 feet deep. "I estimate," says M. Conte,^[12] "that the sinking of a shaft a mile in depth would occupy not less than forty years. I do not know that a depth of 1000 feet has been hitherto passed."^[13]

"Several projects were presented to the Sardinian government, some proposing to shorten the length of the tunnel by raising its level, and others to accelerate the boring of the holes for blasting; but they were all put aside as impossible, or as having been insufficiently studied. The first one seriously considered by the government was that of M. Maus, a Belgian engineer. He proposed to construct a tunnel of 12,230 mètres between Bardonnêche and Modane, with a ruling gradient of 19 in 1000. The advance of the small gallery in front was to be made by means of a machine with chisels, put in motion by springs, that would have cut the rock into blocks—leaving them attached only at the back—which were afterwards to be brought down by means of wedges."

"M. Colladon of Geneva suggested moving the tools of the machine of M. Maus by means of compressed air, but he neither pointed out the means of compressing the air, nor how it was to be applied as a motive power."

"The government had constructed the railway from Turin to Genoa, and engineers were studying how to tug the trains up the incline at Busalla, which has a gradient of 1 in 29. MM. Grandis, Grattoni, and Sommeiller proposed to compress air by means of the 'compresseur à choc' which is now used on the works of the Cenis tunnel, and to employ it for the traction of the trains."

"Mr. Bartlett, an English engineer on the Victor Emmanuel Railway,^[14] had invented a machine for making holes for blasting, which was put in motion by steam. The machine was imperfect, and while experiments were being made with it (by means of compressed air), M. Sommeiller invented the boring-machine which is now used in the tunnel."

"The problem then appeared to be solved. The inventors joined themselves to M. Ranco—who had taken part in their experiments on the Genoa Railway—prepared a scheme, and presented it with confidence to the government, after having found out that they could compress air to a high pressure, that this air could be led from closed reservoirs and transmitted to great distances without a sensible diminution of its pressure, and that it could be employed to move the boring-machine which was intended to make the holes for blasting. A commission was appointed to examine the project, and its members satisfied themselves that the scheme was feasible. The Act of August 15, 1857, authorised the government to construct the section of the Victor Emmanuel Railway between Susa and Modane. MM. Grandis, Grattoni, and Sommeiller, were appointed to direct the works."

"M. Medail indicated the general direction of the tunnel between Modane and Bardonnêche. M. Maus drew his line a little more to the east, nearer to Modane. The engineers who direct the work have approached the latter course, and have selected that which seemed to them to be the shortest, the most easy to come out at, and, especially, the most convenient to lay out."

"It is needless to insist on the importance of the tracing of the course of the tunnel. It was necessary—1st, To establish upon the mountain a sufficient number of marks in order to determine the vertical plane passing through the axis of the gallery; 2. To measure exactly the distance between the two mouths; 3. To determine the difference of level between the two mouths, in order to arrange the gradients of the tunnel."

"These delicate operations were entrusted to MM. Borelli and Copello. M. Grandis undertook the control of the work."

"After the two mouths had been determined upon, they set out from Fourneaux to trace a line in the supposed direction of Bardonnêche. This first line came out in the valley of Rochemolles at a point too far off from that fixed upon, but with its help a second line was drawn which came sufficiently near to the proposed entry. These lines were subsequently still further corrected. These operations occupied the months of August and September 1857."

"The observations were made with a theodolite which had been constructed with the greatest care, and which read to 10" on the vernier. The line has been verified several times by different observers, and the results show that a straight line has been laid out. Supposing that the greatest error" (due to the instrument) "had been made, the deviation from the straight line would not amount to more than one foot. MM. Borelli and Copello make—personally—the observations for the direction and for the verification of the actual course of the tunnel, and we may imagine that they will not readily leave to others such delicate work, upon which the success of the enterprise depends. All the marks on the southern side, and the most important ones on the northern side, were fixed by the first days of October 1857; snowfalls and 'tourmentes' retarded the work, but it was nevertheless completed by the end of the month."

"In 1858 the triangulations and levellings were undertaken, and they were terminated at the end of the year."

"The trigonometrical work has for a base one of the sides of the triangles of the Etat Major, and upon it two sets of triangles have been constructed, one towards the southern and the other towards the northern side. The two systems are formed of twenty-eight triangles, and the number of angles measured is eighty-six. The majority of the angles have been repeated at least twenty times; those of the principal triangles have been taken fifty times, and, of the small ones, at least ten times. The theodolite employed read to 5"."

"One can hardly give an idea of the difficulties that the observers have experienced in the course of their work. At heights like those from which they worked, meteorological changes occur with the greatest rapidity; violent winds overturned their instruments, and mists or clouds concealed the points at the moments they wished to observe them. A single fact will give some notion of the nature of their work. Seven angles had to be measured from the summit of La Pelouse, 10,170 feet above the sea. The observers—who were lodged in the chalets of La Rionda, had to ascend to the summit for seven successive days, and it was seldom possible to measure two angles in the same day."

"The importance of these observations is readily comprehended, and I have described them at some length, because they form the base of the enterprise. One thing is notable. It is the personal care that the engineers have taken. M. Grandis directed the tracing of the line, the triangulation, and the levellings; he assisted at these operations; he selected the bases and points at which 'signals' were to be placed; and all was done under his eye by the engineers, Borelli, Copello, Mella, and Mondino."

On account of the peculiar situation of the ends of the tunnel, two small, connecting, curved tunnels will have to be made. "The construction of these terminal curves is naturally neglected for the establishment of the two false mouths in the direction of the general line."

"The length between the two false mouths is					12,220.00	mètres.
The entry on the side of		Italy is at a height of			1335.38	"
"	"	France	"		1202.82	"
		Difference of level			132.56	"
This difference of level is overcome by a gradient of 222 in 10,000, which rises from the French entry to the centre[15]
				=	135.64	"
A gradient of 1 in 2000, which rises from the Italian entry to the centre[15]
				=	3.06	"
					132.58	"

If a single gradient had ruled throughout, rising from the French to the Italian side, it would have been reduced to 217 in 20,000; but although this would have been of the greatest advantage in working the line, it would have added one more difficulty to the construction of the tunnel. There were enough difficulties without adding another."

"It is, besides, evident that driving the tunnel to a summit doubles the chances of the two ends meeting, and negatives, to a certain extent, the possibilities of error from the two operations upon which the least dependence could be placed,—the triangulation and the levelling. Provided that the two axes are in the same direction, they must meet sooner or later; whether this happens a few yards more to the north or to the south is of no importance."^[16]

At the commencement of the tunnel in 1857, there was no accommodation at either end for those employed on the works; and for a long time both engineers and workmen had to submit to numerous privations. Roads had to be made, and barracks to be erected; one after another, houses and shops were added, and at the present time the tunnel-buildings alone form considerable villages at the two ends.^[17]

The situations of the two mouths are essentially different from each other. That at Bardonnêche comes out at the bottom of the valley of Rochemolles; that at Fourneaux 300 feet above the Cenis road. At the latter end the debris has been shot out at the mouth down the mountain-side; and, large as the tip (in the language of navvies) undoubtedly is, it is difficult to believe one sees all the material that has been extracted from more than two miles and a half of tunnel. It is interesting as showing the greatest angle at which debris will stand. Its faces have, as nearly as possible, an angle of 45.°

During four years the ordinary means of excavation were alone employed, and but 1300 yards were driven. In this time the machines were being constructed which were destined to supersede a large part of the manual labour; at the beginning of 1861 they were sufficiently complete to be put to work, and in the summer of that year I went to Bardonnêche to see them in operation.^[18]

The clocks of the Oulx had just struck twelve on the night of the 16th of August, as the diligence crawled into the village from Briançon, conveying a drunken driver, a still more intoxicated conducteur, and myself. The keeper of the inn at which we stopped declined to take me in, so I sought for repose in a neighbouring oatfield, and the next morning mightily astonished a native when I rose enveloped in my blanket-bag. He looked aghast for a moment at the apparition which seemed to spring out of the ground, and then turning round in a nervous, twitching manner, dropped his spade and fairly bolted, followed by hearty shouts of laughter. Bardonnêche—a little Alpine village whose situation is not unlike that of Zermatt, was about an hour distant. A strange banging noise could be heard a long way off, and a few minutes after my arrival, I stood in one of the shops by the side of the machine which was causing it, and by the side of M. Sommeiller, the inventor of the machine. They were experimenting with one of his famous "perforatrices," and a new form of boring-rod, upon a huge block of rock which was already riddled by more than a hundred holes, varying from one inch to four and a half in diameter. The perforatrice—a simple-looking cylinder fixed in a square frame, and connected with a few pipes and stop-cocks—was placed in a fresh position in front of the rock, and, at a sign from the engineer, was set in motion. A boring-rod darted out like a flash of lightning, went with a crash against a new part of the rock, chipped out several fragments at a blow, and withdrew as quickly as it had advanced. Bang, bang, it went again with the noise of a gong. In ten seconds the head of the borer had eaten itself a hole; in a minute it had all but disappeared; in twelve it had drilled a hole nearly a yard deep, as cleanly as a carpenter could in a piece of wood. The rod not only moved backwards and forwards, and advanced as the hole grew deeper, but turned gently round the whole time; a jet of water, projected with great force, cooled the chisel, and washed out the hips. More air was turned on; the sound of the blows could no longer be distinguished one from another, they made a continuous rattle, and the rate was increased from two hundred to no less than three hundred and forty strokes per minute, or about half as fast again as the motion of the piston-rod of an ordinary express locomotive when going sixty miles an hour.

The pipes are seen which conduct the compressed air for the working of these boring-machines on approaching the tunnel-mouths. They are eight inches in diameter, and are supported by pillars of masonry. As these pipes, outside the tunnel, are exposed to constant variations of temperature-sometimes to as much as 54° Fahr. in a single day—it has been necessary to guard against their expansion and contraction. They have been fixed accordingly at stated intervals by means of iron rods, the lower ends of which are carried through the masonry and bolted to plates on the outside. The intermediate pipes are carried on rollers (d) on the tops of the pillars, and between each of the fixed points there is one pipe having an enlarged mouth—terminated by a cheek—which receives the end (a) of the ordinary pipe. A circular pipe of leather (c) is secured to the cheek by means of a metal washer, and, pressed down by the compressed air on the end of the ordinary pipe, makes the joint sufficiently air-tight, although it does not hinder the advance or the retreat of the pipe. In the tunnel itself—where the temperature is not subject to such fluctuations—these precautions are not necessary, and the pipes are carried along the walls, supported by brackets, as far as the end of the finished work. Through these pipes highly compressed air is conducted, and is delivered at the end of the "advanced gallery" where the boring-machines are at work, with only a slight diminution in its pressure, notwithstanding the escapes which occur at the joints.

On entering the tunnel one is struck by its size. The Italians, with a magnificent disregard of expense, or from regard to the future, have constructed it not only with two pairs of rails,^[19] but with a footpath on each side. From the rails to the crown of the arch its height is just 20 feet, and its width is 26 feet 6 inches. The next thing that is noticed is that it is almost everywhere lined with masonry; a small fraction only of the rock is left unsupported. The stone that is used is not obtained from the tunnel itself, but is quarried several miles away, near to St. Michel.^[20] Not observed, but nevertheless existing, is a covered way about 3 feet 4 inches high, and 4 feet wide, which is made in the floor of the tunnel between the rails; it is in fact a tunnel within a tunnel. Originally its dimensions were less, and it was intended merely as a subway in which the pipes conveying the compressed air might be placed, and as a drain; it was found convenient to enlarge its size, and since that has been done, it has—on at least one occasion—served a purpose for which it was not originally intended. On the 15th of September 1863, a sudden fall of rock occurred, which killed several miners and imprisoned about sixty others who were at work in the advanced gallery. They were greatly alarmed, and expected to be starved; but at last one of them remembered this subway, and they escaped by its means. Since that time the miners, knowing they have this exit, have troubled themselves very little about éboulements.

The temperature of the tunnel remains tolerably uniform throughout the year, but it is much higher in some parts than it is in others. On the occasion of my last visit, the exterior temperature was 63½° Fahr. in the shade; a mile from the entrance it was 65°, and the mouth looked like the sun on a misty November day. At two miles the thermometer showed 70°, the atmosphere had become foul, and the mouth was invisible. In two hundred and fifty paces more, it had risen to 75°, the tunnel was filled with dense clouds of smoke, the light of an ordinary miner's lamp could not be perceived at the distance of five or six yards, and respiration was difficult, for the atmosphere was vile. This was the end of the finished work: it is from hence that the air is drawn by the pumping-engines at the mouth, and it is hereabouts that all the foul vapours naturally accumulate and hang. The great vault was no longer overhead, but the way was reduced to a drift eight or nine feet wide and scarcely as much high, encumbered with waggons filled with débris, between which and the walls one could barely pass. In a hundred feet or so, we emerged—comparatively speaking—into a blaze of light. Two hundred greasy, smoky, but still light-giving lamps, hung from the walls. Drops of water flashed past them like gems. Two hundred men toiled at the enlargement of the gallery—bearded, grimy men, some on their backs, some on their sides, some working overhead, some half naked, some quite naked—all tapping laboriously at their mining-rods, and all perspiring profusely. The temperature had risen to 81½°.^[21] The multitude of the lights, the crowd of men, and the obscurity of the smoke, help to make the tunnel look an immense size—in fact, at this part, it is sometimes but little less than 30 feet high and 35 feet wide; for not merely has the rock to be removed at the top and sides, which is afterwards replaced by masonry, but it is occasionally excavated for an inverted arch, which is placed wherever it is necessary.

The temperature is, as nearly as possible, the same at the roof of the gallery as it is on the floor; for jets of compressed air are let off above. The work of the masons would otherwise be unendurable.

There was a difference then of 18° between the temperature at the mouth and at the end of the finished work. In winter this amount would be trebled or quadrupled. How much of the increase is due to the lights, men, and horses, and how much to the natural temperature of the rock? If the heat increased in the tunnel, yard by yard, in the same proportion as it does when descending into the earth, the temperature in its centre should be about 90° higher than at its mouth. Although it is known that the rate of increase is very much less than this, the actual rate is not known. I believe it is correct to say that not a single observation has been made upon the natural temperature of the rock since the tunnel has been commenced. Four-fifths of it are now driven. The opportunity for observation has been lost; for, apart from the cooling which must inevitably have taken place, almost the whole of the tunnel has been lined with masonry, and it is not to be expected that any person, or any body of persons, will incur the expense, even if they were permitted, of removing this, and then making the necessary holes. It is to be hoped that some observations will be made on the remaining portion, for similar opportunities are not likely to occur very frequently.

About 2000 feet on the French side of the tunnel was undergoing the processes of enlargement and completion in the summer of 1869.^[22] In some places portions of the advanced gallery remained untouched, and then one came to caverns, such as have been described above. This section was being completed faster than the advanced gallery was being driven. It was pleasant to get away from it farther into the bowels of the mountain; the heat became less, and the atmosphere more pure. The noise of the hammers died gradually away, and at last no sound whatever could be heard, except of our own footsteps and of water running in the subway. After a time the banging of the chisels could be distinguished which were at work on the front of the attack. Five hundred paces took us to them.^[23] The ponderous frame, technically called "l'affût," sup-ported nine of the machines known as "perforatrices;" each perforative propelled a boring-rod, and each boring-rod was striking the rock at the rate of 200 strokes per minute, with a force of 200 pounds.^[24] The terrific din that these 1800 strokes per minute, given with such force, make in a rock-chamber that is only 8 ft. 3 in. high, and 9 ft. 2½ in. wide, can hardly be imagined; neither can an adequate idea be given of the admirable manner in which the machines accomplish their work. In spite of the noise and the cramped position in which the men necessarily toil on account of the limited space, the work goes steadily forward day and night. Each man knows his part. The foremen direct by signs rather than by words; the labourers guide the chisels; the workmen regulate the supply of air; the machinists are ready in case of accident; slim boys, with long-nosed cans, oil the machinery. Order triumphs in the midst of apparent confusion. One sees now the results of years of perfecting and of practice. Things were very different at the beginning. Then, says M. Conte, "everything was new, not only to the workmen, but also to those who had the direction. . . . The work of perforation was commenced at Bardonnêche on January 12, 1861, but for several days only a single perforatrice was in action, then a second was added, and by the 20th a certain amount of useful work had been done. On the 26th the number of the perforatrices was increased to four, and by working eight hours per day, 10 or 12 holes were made about a yard in depth. On the 12th of February they had perfected about 32 yards of the advanced gallery, which had been left unfinished, and then arrived at the front of the attack. The whole difficulty was there. The number of the machines was again increased, but during ten days there was little result. On the 22d February the works were suspended, in order to make alterations suggested by experience; and it was recommenced on the 2d of March. During the first half of this month an advance of half-a-metre was accomplished in two days, by working seven hours a-day; but towards the end of the month the work had become more easy, and it was possible to perform the whole of the operation in a single day, and to obtain a daily advance of 18 inches to two feet."

"In April, the improvements introduced, and the practice acquired, caused better progress, and in the middle of the month the work of perforation was accomplished in eight or nine hours."

"In the month of May, when nine perforatrices were at length at work, progress was stopped by exterior causes, and was suspended for two months."

"From July to the 19th of August the work was continued, but only one attack per day was made, on account of there not being a sufficient number of instructed persons to carry on the work incessantly. Still it was carried on with regularity, and the advance was 28 inches to 3 feet per day. The perforation was generally accomplished in six hours."

"From the 19th of August the work was continued day and night, but at first, in consequence of the inexperience of some of the employées, the depth of the holes had to be reduced to two feet, and that depth occupied them twelve hours. Little by little this fresh band of workmen became as skilful as the first, and at the end of two months the two attacks were carried on with regularity."^[25] The best form of boring-rod for all kinds of rock, excepting such as are homogeneous, was hit upon in 1861, and it has been in use ever since. The head is in the form of a Z. For homogeneous rock, the ordinary form of chisel is found best. Almost all the details of the machinery, the size of the gallery, the dimensions and number of the holes, and the manner of firing them, have been changed since the beginning; the general principles alone remain unaltered. The present system is as follows. A hole 4¾ inches in diameter is made to a depth of about a yard, towards the centre of the drift, but rather nearer to the floor than to the roof. Fifty to sixty holes, according to circumstances, of less diameter, but of about equal depth, are then driven into the remainder of the face.
CROSS SECTION OF THE ADVANCED GALLERY.All the holes are then dried and cleaned by a jet of compressed air, the "affût" is withdrawn behind strong iron-bound doors, and six of the small holes nearest to the large are charged and fired. The force of the explosion goes in the direction of least resistance, that is towards the central hole, and a breach is made such as is indicated in the longitudinal section by the thick dotted line. The remaining holes are then charged and fired in sets of six or eight at a time, those nearest to the breach being exploded first. This system has been found more economical than firing a larger number of shots at one time. The waggons are then advanced, and the débris is cleared away; the two pairs of rails at the sides, shown in the cross section, are for
LONGITUDINAL SECTION OF THE END OF THE ADVANCED GALLERY.waggonets, whose contents are afterwards transferred to large waggons. The "affût" is then again advanced. These operations are now repeated with unvarying regularity twice every day.

The temperature at the working face of the advanced gallery is seldom higher than from 75° to 76°, and the atmosphere is as pure as can be desired, when the machines are at work.^[26] This, it must be remembered, is notwithstanding the presence of more than thirty men,^[27] and almost as many lamps, in a space about nine feet wide, eight high, and fifty long. The comparative lowness of the temperature is of course due to the expansion of the compressed air.

At the distance of a hundred and sixty paces, the sound of the machines could not be distinguished, and the atmosphere again gradually deteriorated as we approached the region which may, not improperly, be termed infernal. Once more we passed through the foul vapours and by the army of miners. Laborious as the work of these men undoubtedly is, it is lighter and far less dangerous than that of our coal-cutters. The heat, although it seems considerable to one coming from a lower temperature, is not excessive, and this may be inferred from seeing how few men are unclothed. They work readily enough for their three francs a-day,^[28] and take to their labour cheerfully; very few skulkers can be seen in the Mont Cenis tunnel. The following table shows how small is the risk to life.

Fatal Accidents which have occurred at the Great Tunnel of the Alps from the commencement of the works to August 1869:—
Inside the Tunnel.			Outside the Tunnel.
From falls of rock	8		Falls from heights	2
Accidents from waggons	14		Accidents from waggons	4
Premature explosions	3	—25	Explosion of gunpowder	5	—11
Total . 36

It will be seen from this that one-half of the fatal accidents have arisen from men being run over by waggons. This has chiefly come from the impossibility of making the miners walk on the footways at the sides of the tunnel. They will walk. on the rails. The result is that they are not unfrequently killed, although the greatest precautions are taken with the waggons descending with débris. The total is insignificant when one considers the number of men engaged and the length of time over which it is spread, and it compares favourably with almost any other enterprise of similar magnitude.

The waggons laden with débris run down, on the French side, by their own weight, on account of the gradient, and so did the truck on which I descended with my guide—the courteous engineer who directs the works. Fresh relays of miners were entering, and those whom they relieved were coming out with their arms around each others' waists "in the manner of schoolboys and lovers." The air seemed chilly, although it was a bright summer day; and our nostrils, for hours after leaving the tunnel, yielded such supplies of carbon as to suggest that the manufacture of compressed soot might be profitably added to the already numerous industries of the works.

About four thousand men are now employed on the tunnel,^[29] and they complete ten to eleven feet every day. The average daily progress of the last five years is ten feet one inch. Each yard of progress costs at the present time about £200, or just double the average of railway tunneling in England.^[30] There are many yards, however, which have cost infinitely more than £200 per yard. The work is now so far advanced that the engineers can estimate with some probability what the total expenditure will amount to. They place it at £3,000,000 (£224 per yard), which sum includes the expense of the whole of the machinery and of the exterior works. This amount does not seem extravagant when we remember that for every yard of advance, never less—and frequently more—than seventy cubic yards of rock have to be excavated, and to be carried away (at the present time) a distance of three miles; that about twenty-five cubic yards of masonry have to be built, the stone for which is conveyed twelve miles in a mountainous country; that all the machinery employed has been constructed and invented expressly for the tunnel, and that the creation of two small towns has been necessary. The strata which have been pierced agree very satisfactorily in their nature and in their thickness with the indications of the geologists.^[31] The engineers therefore believe that no greater difficulties will be encountered than those which have been overcome. Remarkably little water has been met with: the miner's dreaded enemy seems to have fled before the engineer who has utilised its power. I have not entered into a description of the manner in which this has been accomplished, because it has been frequently done before; but there is nothing more interesting in regard to the tunnel than the way in which the waste power of nature has been applied for the reduction of the difficulties of the undertaking. There is not a single steam-engine on the works: everything is done with compressed air, or by hydraulic power. Just one half of the tunnel was driven at the end of October 1866, after more than nine years of labour. The third quarter was finished by the end of 1868,^[32] Unless extraordinary obstacles are encountered, the two ends will probably meet in February 1871;^[33] but it will be long after that date before the tunnel will be used for traffic.^[34]

Will the two ends meet? The engineers are confident that they will. One important fact remains to be pointed out. The two sides have not advanced with equal rapidity. On the Italian side the summit is nearly gained—before these pages are published it will have been passed; but on the French side they are nearly 2000 yards short of it. The work is still to be carried on simultaneously, and, consequently, on the Italian side they will shortly begin to descend. M. Conte mentioned^[35] that one of the reasons which influenced the engineers to drive the tunnel to a summit, was, that by so doing, any error in the determination of its length, or in the levels, would be negatived. It was only necessary that the two ends should be driven in the same line,—they would be sure to meet sooner or later. This was on the supposition that the two gradients would be maintained until the two ends met. The whole of this advantage is going to be sacrificed. If there is any material error in the determination of the length or of the levels, the two ends may not meet. One has not to go farther than the summit of the Mont Cenis pass itself to show that errors may creep into trigonometrical work, even when it is conducted by distinguished engineers. The height of that pass has been obtained by two independent surveys; one, carried through Trance from the level of the sea, and the other carried through Italy from the level of the sea; yet the Italians make the summit 59 feet higher than the French.

When the great tunnel of the Alps is completed, will it be a useless marvel? or will locomotives be able to work in it? Will the trains arrive at the ends with cargoes of asphyxiated passengers who will have to be revived with draughts of compressed air? or will there be no trouble on account of ventilation? It must not be argued that because it is impossible for locomotives to work in the tunnel at present, it will be impossible for them to work in it when it is completed. The temperatures of the two sides will frequently be different, and that alone will produce considerable currents. The very passage of the trains will do a good deal. Besides this, there is already a large amount of ventilating power established at the two ends, and it can be kept in action at a small expense. I saw at the Fourneaux (Modane) mouth, on my last visit, the pumping-engines that had been set up about two years before. There were four cylinders, each 16 feet 4 inches in diameter, with a stroke of 6 feet 6 inches. Only two were at work, yet—at a distance of two miles from the mouth—they produced a very sensible current flowing into the tunnel, which was indicated by the miners' lamps that we carried. There is no reason to be afraid that the eminent engineer, who has hitherto shown himself equal to all the difficulties which have arisen, will be beaten by the ventilation.

M. Conte, at the conclusion of his pamphlet, pays a high tribute of praise to M. Sommeiller, and properly speaks of him as " the soul of the enterprise." " We may quote him as a model of courage and devotion If one may believe the companions of his youth, he followed the idea, which he now realises, at the time he was studying at the university of Turin. This idea he has never abandoned." Englishmen ought to be amongst the first to recognise his boldness and perseverance, although they have played no part in the execution of the tunnel.^[36] It is the grandest conception of its kind, and when it is completed, it will be not only—in a double sense—one of the highways of Europe, but it will most likely become the high road to India.

It is humiliating to compare the working of our coal-mines with the operations carried on in the great tunnel of the Alps. In the former we see the old, barbarous, wasteful methods still employed, with disregard of human life, and for the future. In the latter, mechanical power, skilfully applied, economises labour, and gives safety and comfort to those who are at work. The exhaustion of our coal-fields, which recent inquiries have placed at a more distant date than was expected a few years ago, is a thing that is inevitable sooner or later. Actual exhaustion is not so much to be feared as inability to compete with foreign producers. The question is adjourned, but it will presently be forced upon public attention again. When it becomes too pressing to be neglected, then, possibly, there will be a chance of the condition of our miners being ameliorated; but it is improbable so long as gigantic public subscriptions pay for the effects of private neglect, which actually tend to perpetuate what they are intended to cure, that the chief sinners will take proper action. When they take alarm, then perhaps there will be salvation for the pitmen. The fact that two hundred of their men lose their lives every year by fire-damp explosions will not move British pit-owners so readily as the disagree-able truth that the time is rapidly approaching when they will be unable to compete with foreign markets, unless they work with greater economy. We have heard times without number that miners are careless; that they will smoke their pipes where they ought not; that they will carry forbidden matches, or even break open their safety-lamps to get a light. It is useless to combat such habits by repressive enactments, and childish to talk of double-locking lamps because single-locked ones are found ineffectual. The more difficulty there is in obtaining a light, the more men will struggle to get one. The only way to prevent explosions is to render them impossible, and that can be accomplished, to a large extent at least, by better ventilation. Coal can be got more economically, and the ventilation can be improved, by the use of one and the same means. Steam machinery cannot be used in coal-pits for the same reason that it could not in the great tunnel of the Alps; but machines moved by compressed air can. A machine for coal-cutting worked by compressed air was patented so long ago as 1861, and has been successfully at work in a pit in Yorkshire^[37] for a long time. Its action is an imitation of that of the miner's pick; it cuts a narrow groove 3 ft. 9 in. deep along the bottom of the coal, which is afterwards broken down in the usual way. Three times more coal can be got by four men with it in a day than they can get without it. The waste of coal in the operation of holing is reduced by two-thirds. That is to say, if this machine could be used in all the pits in the kingdom, there would be an actual saving of 8,000,000 to 9,000,000 tons of coal per annum! There are other (hydraulic) coal-cutting machines at work in collieries in the north of England, which are equally economical, and which will, like Mr. Firth's machine, work narrow seams at a profit which it would not pay to work by hand; but they do not possess the important ventilating power, which is one of its chief recommendations. The expansion of the air not only lowers the temperature, but it drives all the gas away from the working-face. That this is done is sufficiently proved by the fact that there has not been a single explosion at West Ardsley since the machine has been in use, although there were many minor ones before it was introduced.

Who can say the condition of our coal-mines is satisfactory when such results are attainable? Yet who can touch the evil? The man who shall succeed in improving their ventilation will be a greater benefactor to his country than Sir Humphrey Davy, and will well deserve public reward; although, perhaps, he will be more likely to incur unmerited odium.

---

1. See the general map.
2. This third rail, or, as it is termed, "the centre rail," is laid on all the steep portions of the line, and round all except the mildest curves. Thirty miles, in all, of the road have the centre rail.
3. These engines are described in the reports by Captain Tyler to the Board of Trade.
4. The inclination of the steepest part of Old Holborn Hill.—Roney's Rambles on Railways.
5. On the Italian side there are about three-quarters of a mile of strongly-built avalanche galleries, and more than three miles of covered way.
6. The carriages are not coupled in the ordinary way, and although there are no buffers, properly speaking, and in spite the speed of the train being changed incessantly, there is a freedom from the jarring which is so common on other lines. The reason is simply that the carriages are coupled up tightly.
7. The Great Indian Peninsula Railway, the line with the celebrated Bhore Ghaut incline, sixteen miles long, on an average gradient of one in forty-eight, which is said to have cost £800,000, or about double the entire cost of the Mount Cenis Railway, and six times its cost mile for mile, The Fell railway cost £8000 per mile.
8. The trains take 5½ hours one way and 5¼ hours the other. These times are inclusive of an hour and a half of stoppages.
9. It is said that a number of railway directors were nearly suffocated on one of the early experimental trips, and that peremptory orders were given to remove portions of the roof.
10. These are the times actually occupied in the tunnel.
11. The Mont Cenis Tunnel will be 13,364 yards long. The lengths of some of the better known tunnels in England are given below, for the sake of comparison.

    Shakespeare	(South-Eastern Railway)	1430	yards	7	shafts.
    Kilsby	(North-Western Railway)	2398	"	2	"
    Box	(Great Western Railway)	3123	"	11	"
    Woodhead	(Man., Sheffield, and Line. Railway)	5300	"	?	"

    The last-named is the longest railway tunnel in England.—Enc. Brit, Art. " Railways."

    The longest canal tunnel in England is the Marsden, on the Huddersfield Canal.—Roney's "Rambles on Railways".

12. M. Conte, a well-known French engineer, was a member of a commission appointed to examine the progress of this tunnel in 1863. His report is the most accurate and the most complete account of it that has been published.
13. M. Conte refers to tunnel-shafts.
14. The Victor Emmanuel Railway Company has ceased to exist. The section in France is joined to the Paris, Lyons, and Mediterranean Railway, and that in Italy to the Alta Italia system. The railway from the French mouth of the tunnel to St. Michel will be made at the cost of the Paris, Lyons, and Mediterranean Company.
15. The summit will be a few feet higher than M. Conte states, the gradients having been increased since the commencement of the works.
16. Conte. Conférences faites à l'Ecole Impériale des Ponts et Chaussées. 1864.
17. It is sufficient to indicate those at Bardonnêche only. The principal ones are: 1. Close to the tunnel-mouth—lodgings for the miners, the principal storehouses, stables, forges for repairing the drills. 2. At Bardonnêche, half-a-mile distant from the mouth—large barracks for the workmen; six other buildings for workmen; one house for other employees; repairing-shops for the machinery; storehouses; a foundry; the building containing the "compresseurs à choc," and the reservoirs for feeding the same; a gasworks; a building containing an infirmary, washhouses, etc.; two buildings for "compresseurs à pompe;" one building for new reservoirs of compressed air; a cantine and a porter's lodge. An enumeration of the buildings at Fourneaux (Modane) would be nearly a repetition of the above.
18. In the previous year I had visited Modane, and favoured by introductions from M. Ch. Lafitte, at that time President of the Victor Emmanuel Railway, had been shown all that there was to be seen. I visited Modane again recently, and, for the third time, went to the end of the advanced gallery. I have to thank M. Mella and Sig. Borelli, the directors of the works in 1861 at Modane and Bardonneche respectively, for their attention in 1860-1, and particularly Signor Copello, the present director at Modane, for the facilities given and for the information afforded by him.
19. The lines which will connect it with existing railways are to be only single lines.
20. Here, and in the subsequent pages, the French side is alone referred to, unless it is otherwise specified; but the description would serve almost equally for the Italian side.
21. It is almost unnecessary to remark that no stout men are seen in the tunnel.
22. The monthly advances which are sometimes quoted in English newspapers refer to the advanced gallery, not to the finished work.
23. In addition to the 2000 feet of unfinished work mentioned above.
24. The perforatrices are independent machines, and one can "be stopped or removed without arresting the progress of the others.
25. On the Italian side, in order to advance one metre:—

    1862.	1863.
    120 holes, each 30 to 32 inches in depth, had to be bored. 110 lbs. of powder were consumed. 200 mètres of match. 190 drills were put hors de combat.	96 holes, 36 inches deep, were bored. 94½ lbs. of powder were consumed 210 mètres of match. 185 drills were used up
    On the French side, in order to advance one metre:—
    1863 103 holes, 34 inches deep, were bored. 125¼ lbs. of powder were consumed 200 mètres of match. 158 drills were used up Conic.

26. The temperature is raised to 80° or 86° after the mines are exploded.
27. 1 chef; 4 machinists; 2 master miners, who determine the direction of the holes; 8 labourers, who guide the boring-rods; 9 workmen, who look after the perforatrices; 5 boys; 8 labourers; 2 workmen, who keep up communication with the exterior,—in all, 39 persons.
28. The workmen in the advanced gallery receive five francs a-day, and a small bonus per mètre if they exceed a certain fixed distance.
29. On the French side they are employed as follows (subdivisions are omitted for the sake of brevity):—

    (1.)	In the advanced gallery—
    		'Ajusteurs'		13
    		Miners		14
    		Labourers		140
    		Boys		13		180
    (2.)	Enlargement by manual labour—
    		Miners		510
    		Labourers		180
    		Boys		30		720
    	Masonry—
    		Masons and dressers of stone		58
    		Labourers		170
    		Boys		52		280
    (3.)	Manufactories, machinery, stores (exterior works)-
    		Smiths, joiners, fitters, etc.		120
    		Labourers		440
    		Boys		10		570
    (4.)	Overseers, foremen, clerks, etc. ....					60
    (5.)	Platelayers, transport of materials, etc.					180
    				Total		1990
    	Horse-power of machines—
    		Hydraulic wheels			480
    		Ventilating	machines		300
    		Sundry	"		80
    		Total horse-power of machinery			860
    		Horses employed in clearing away débris			80

30. Encyclo. Brit. art. "Railways."
31. Table of the strata which have been pierced on the French side of the great tunnel of the Alps:—

    			Mètres			Mètres		Thickness of the Strata in Metres.
    1.	Débris and pebbles	from	0		to	128		128
    2.	Anthracitic schists	"	128		"	2095	.35	1967	.35
    3.	Quartzite	"	2095	.35	"	2476	.75	381	.40
    4.	Anhydrite	"	2476	.75	"	2696	.90	220	.15
    5.	Compact calcareous rock	"	2696	.90	"	2780	.20	34
    6.	Talcose schists	"	2730	.90	"	2780	.20	49	.30
    7.	Compact calcareous rock	"	2780	.20	"	2802	.02	21	.82
    8.	Anhydrite	"	2802	.02	"	2831	.75	29	.73
    9.	Compact calcareous rock	"	2831	.75	"	2852	.95	21	.20
    10.	Anhydrite	"	2852	.95	"	2867	.15	14	.20
    11.	Calcareous schists	"	2867	.15	"	3264		396	.85
    12.	Anhydrite	"	3264		"	3334	.45	70	.45
    11.	Calcareous schist (the same as at Berdonnêche)	"	3334	.45	"	continues		?

    On the Berdonnêche side the tunnel passes through schist alone.

32. The advanced gallery only.

33. Table showing the Progress of the Advanced Gallery on each side,
    from the Commencement up to 1st November 1869.

    Bardonnêche.

    Modane.

    Total of
    

    the two
    sides per
    annum

    General
    

    Total

    Year.

    Advance
    

    in mètres.

    Total.

    Advance
    

    in mètres.

    Total.

    By manual labour		1857
    		1858
    		1859
    		1860
    		1861
    		1862
    By mechanical means.		1861
    		1862
    		1863
    		1864
    		1865
    		1866
    		1867
    		1868
    		1869

    27	.28		725	.00
    257	.57
    236	.35
    203	.80
    170	.00		5337	.40
    380	.00
    426	.00
    621	.20
    765	.30
    812	.70
    824	.30
    638	.60
    699	.30

    10	.80		921	.00
    201	.95
    132	.75
    139	.50
    193	.00
    243	.00
    "	"		3407	.00
    "	"
    376	.00
    466	.65
    458	.40
    212	.29
    687	.81
    681	.55
    524	.30

    38	.08		1646	.00
    459	.52
    362	.10
    343	.30
    193	.00
    243	.00
    170	.00		8744	.40
    380	.00
    802	.00
    1087	.85
    1223	.70
    1024	.99
    1512	.11
    1320	.15
    842	.10

    Total advance at Bonnêche

    $\scriptstyle {\left.{\begin{matrix}\ \\\ \end{matrix}}\right\}\,}$

    6062

    .40

    Total advance at Modane

    $\scriptstyle {\left.{\begin{matrix}\ \\\ \end{matrix}}\right\}\,}$

    4328

    .00

    Total advance at both ends

    $\scriptstyle {\left.{\begin{matrix}\ \\\ \end{matrix}}\right\}\,}$

    10,390

    .40

    See Appendix for the progress of the work since this date.

34. The railways which will connect the tunnel with existing lines will be difficult and costly works, with numerous tunnels and bridges. A good deal of the heavy work is done on the line between Susa and Bardonneche, but on the French side the works are almost untouched.
35. See p. 61.
36. The machinery has been principally made in Belgium; the engineers are French and Italians, and the subordinates, for the most part, Piedmontese and French.
37. The West Ardslev.