Chapter 9

ASCENT OF THE MOUNTAIN.

The most suitable time for ascending Etna.--The ascent commenced.-- Nicolosi.--Etna mules.--Night journey through the upper Regions of the mountain.--Brilliancy of the Stars.--Proposed Observatory on Etna.--The Casa Inglesi.--Summit of the Great Crater.--Sunrise from the summit.--The Crater.--Descent from the Mountain.--Effects of Refraction.--Fatigue of the Ascent.

The ascent of Mount Etna has been described many times during the last eighteen centuries, from Strabo in the second century to Dr. Baltzer in 1875. One of the most interesting accounts is certainly that of Brydone, and in this century perhaps that of Mr. Gladstone. Of course the interest of the expedition is greatly increased if it can be combined with that spice of danger which is afforded by the fact of the mountain being in a state of eruption at the time.

The best period for making the ascent is between May and September, after the melting of the winter snows, and before the autumnal rains. In winter snow frequently extends from the summit downwards for nine or ten miles; the paths are obliterated, and the guides refuse to accompany travellers. Even so late in the spring as May 29th Brydone had to traverse seven miles of snow before reaching the summit. Moreover, violent storms often rage in the upper regions of the mountain, and the wind acquires a force which it is difficult to withstand, and is at the same time piercingly cold. Sir William Hamilton, in relating his ascent on the night of June 26th, 1769, remarks that, if they had not kindled a fire at the halting place, and put on much warm clothing, they would "surely have perished with the cold." At the same time the wind was so violent that they had several times to throw themselves on their faces to avoid being overthrown. Yet the guides said that the wind was not unusually violent. Some writers, well used to Alpine climbing, have asserted that the cold on Etna was more severe than anything they have ever experienced in the Alps.

The writer of this memoir made the ascent of the mountain in August 1877, accompanied by a courier and a guide. We took with us two mules; some thick rugs; provisions consisting of bread, meat, wine, coffee, and brandy; wooden staves for making the ascent of the cone; a geological hammer; a bag for specimens; and a few other requisites. It has to be remembered that absolutely nothing is to be met with at the Casa Inglesi, where the halt is made for the night; even firewood has to be taken, a fire being most necessary in those elevated regions even during a midsummer's night. For some time previous to our ascent the weather had been uniformly bright and fine, and there had been no rain for more than three months. The mean temperature in the shade at Catania, and generally along the eastern sea-base of the mountain, was 82° F.

As we desired to see the sunrise from the summit of the mountain, we determined to ascend during the cool of the evening, resting for an hour or two before sunrise at the Casa Inglesi at the foot of the cone. Accordingly we left Catania soon after midday, and drove to Nicolosi, twelve miles distant, and 2,288 feet above the sea. The road for some distance passed through a very fertile district; on either side there were corn fields and vineyards, and gardens of orange and lemon trees, figs and almonds, growing luxuriantly in the decomposed lava. About half way between Catania and Nicolosi stands the village of Gravina, and a mile beyond it Mascalucia, a small town containing nearly 4000 inhabitants. Near this is the ruined church of St. Antonio, founded in 1300. Nine miles from Catania the village of Torre di Grifo is passed, and the road then enters a nearly barren district covered with the lava and scoriæ of 1527. The only prominent form of vegetation is a peculiar tall broom--_Genista Etnensis_--which here flourishes. We are now entering the region of minor cones; the vineclad cone of Monpilieri is visible on the left, and just above it Monti Rossi, 3,110 feet above the sea; to the right of the latter we see Monte San Nicola, Serrapizzuta, and Monte Arso. We reach Nicolosi at half-past four; for although the distance is short, the road is very rugged and steep.

Nicolosi has a population of less than 3,000; it consists of a long street, bordered by one-storied cottages of lava. In the church the priests were preparing for a _festa_ in honour of S. Anthony of Padua. They politely took us into the sacristy, and exhibited with much pride some graven images of rather coarse workmanship, which were covered with gilding and bright coloured paint. Near Nicolosi stands the convent of S. Nicola dell' Arena, once inhabited by Benedictine monks, who however were compelled to abandon it in consequence of the destruction produced by successive shocks of earthquake. Nicolosi itself has been more than once shaken to the ground. We dined pretty comfortably, thanks to the courier who acted as cook, in the one public room of the one primitive inn of the town; starting for the Casa Inglesi at 6 o'clock. The good people of the inn surrounded us at our departure and with much warmth wished us a safe and successful journey.

For a short distance above Nicolosi, stunted vines are seen growing in black cinders, but these soon give place to a large tract covered with lava and ashes, with here and there patches of broom. There was no visible path, but the mules seemed to know the way perfectly, and they continued to ascend with the same easy even pace without any guidance, even after the sun had disappeared behind the western flank of the mountain. In fact, you trust yourself absolutely to your mule, which picks his way over the roughest ground, and rarely stumbles or changes his even step. I found it quite easy to write notes while ascending, and even to use a pocket spectroscope at the time of the setting sun. Subsequently we saw a man extended at full length, and fast asleep upon a mule, which was leisurely plodding along the highway. The same confidence must not however be extended to the donkeys of Etna, as I found to my cost a few days later at Taormina. Here the only animal to be procured to carry me down to the sea-shore, 800 feet below, was a donkey. It was during the hottest part of the day, and it was necessary to carry an umbrella in one hand, and comfortable to wear a kind of turban of many folds of thin muslin round one's cap. The donkey after carefully selecting the roughest and most precipitous part of the road, promptly fell down, leaving me extended at full length on the road, with the open umbrella a few yards off. At the same time the turban came unfolded, and stretched itself for many a foot upon the ground. Altogether it was a most comical sight, and it reminded me forcibly, and at the instant, of a picture which I once saw over the altar of a church in Pisa, and which represented S. Thomas Aquinas discomfiting Plato, Aristotle, and Averröes. The latter was completely overthrown, and in the most literal sense, for he was grovelling in the dust at the feet of S. Thomas, while his disarranged turban had fallen from him.

The district of lava and ashes above Nicolosi is succeeded by forests of small trees, and we are now fairly within the _Regione Selvosa_. At half-past 8 o'clock the temperature was 66°, at Nicolosi at 4 o'clock it was 80°. About 9 o'clock we arrived at the Casa del Bosco, (4,216 feet), a small house in which several men in charge of the forest live. Here we rested till 10 o'clock, and then after I had put on a great-coat and a second waistcoat, we started for the higher regions. At this time the air was extraordinarily still, the flame of a candle placed near the open door of the house did not flicker. The ascent from this point carried us through forests of pollard oaks, in which it was quite impossible to see either a path or any obstacles which might lie in one's way. The guide carried a lantern, and the mules seemed well accustomed to the route. At about 6,300 feet we entered the _Regione Deserta_, a lifeless waste of black sand, ashes, and lava; the ascent became more steep, and the air was bitterly cold. There was no moon, but the stars shone with an extraordinary brilliancy, and sparkled like particles of white-hot steel. I had never before seen the heavens studded with such myriads of stars. The milky-way shone like a path of fire, and meteors flashed across the sky in such numbers that I soon gave up any attempt to count them. The vault of heaven seemed to be much nearer than when seen from the earth, and more flat, as if only a short distance above our heads, and some of the brighter stars appeared to be hanging down from the sky. Brydone, in speaking of his impressions under similar circumstances says:

"The sky was clear, and the immense vault of heaven appeared in awful majesty and splendour. We found ourselves more struck with veneration than below, and at first were at a loss to know the cause, till we observed with astonishment that the number of the stars seemed to be infinitely increased, and the light of each of them appeared brighter than usual. The whiteness of the milky-way was like a pure flame that shot across the heavens, and with the naked eye we could observe clusters of stars that were invisible in the regions below. We did not at first attend to the cause, nor recollect that we had now passed through ten or twelve thousand feet of gross vapour, that blunts and confuses every ray before it reaches the surface of the earth. We were amazed at the distinctness of vision, and exclaimed together, 'What a glorious situation for an observatory! had Empedocles had the eyes of Galileo, what discoveries must he not have made!' We regretted that Jupiter was not visible, as I am persuaded we might have discovered some of his satellites with the naked eye, or at least with a small glass which I had in my pocket."

Brydone wrote a hundred years ago, but his idea of erecting an observatory on Mount Etna was only revived last year, when Prof. Tacchini the Astronomer Royal at Palermo, communicated a paper to the Accademia Gioenia, entitled "_Della Convenienza ed utilita di erigere sull' Etna una Stazione Astronomico-Meteorologico_." Tacchini mentions the extraordinary blueness of the sky as seen from Etna, and the appearance of the sun, which is "whiter and more tranquil" than when seen from below. Moreover, the spectroscopic lines are defined with wonderful distinctness. In the evening at 10 o'clock, Sirius appeared to rival Venus, the peculiarities of the ring of Saturn were seen far better than at Palermo; and Venus emitted a light sufficiently powerful to cast shadows; it also scintillated. When the chromosphere of the sun was examined the next morning by the spectroscope, the inversion of the magnesium line, and of the line 1474 was immediately apparent, although it was impossible to obtain this effect at Palermo. Tacchini proposes that an observatory should be established at the Casa Inglesi, in connection with the University of Catania, and that it be provided with a good six-inch refracting telescope, and with meteorological instruments. In this observatory, constant observations should be made from the beginning of June to the end of September, and the telescope should then be transported to Catania, where a duplicate mounting might be provided for it, and observations continued for the rest of the year. There seems to be every probability that this scheme will be carried out in the course of next year.

During this digression we have been toiling along the slopes of the _Regione Deserta_ and looking at the sky; at length we reach the _Piano del Lago_ or Plain of the Lake, so called because a lake produced by the melting of the snows existed here till 1607, when it was filled up by lava. The air is now excessively cold, and a sharp wind is blowing. Progress is very slow, the soil consists of loose ashes, and the mules frequently stop; the guide assures us that the Casa Inglesi is quite near, but the stoppages become so frequent that it seems a long way off; at length we dismount, and drag the mules after us, and after a toilsome walk the small lava-built house, called the Casa Inglesi, is reached (1.30 a.m., temperature 40° F.) It stands at a height of 9,652 feet above the sea, near the base of the cone of the great crater, and it takes its name from the fact that it was erected by the English officers stationed in Sicily in 1811. It has suffered severely from time to time from the pressure of snow and from earthquakes, but it was thoroughly repaired in 1862, on the occasion of the visit of Prince Humbert, and is now in tolerable preservation. It consists of three rooms, containing a few deal chairs, a table, and several shelves like the berths of ships furnished with plain straw mattresses; there is also a rough fireplace. We had no sooner reached this house, very weary and so cold that we could scarcely move, than it was discovered that the courier had omitted to get the key from Nicolosi, and there seemed a prospect of spending the hours till dawn in the open air. Fortunately we had with us a chisel and a geological hammer, and by the aid of these we forced open the shutter serving as a window, and crept into the house; ten minutes later a large wood fire was blazing up the chimney, our eatables were unpacked, some hot coffee was made, and we were supremely comfortable.

At 3 a.m. we left the Casa Inglesi for the summit of the great crater, 1,200 feet above us, in order to be in time to witness the sunrise. Our road lay for a short distance over the upper portion of the Piano del Lago, and the walking was difficult. The brighter stars had disappeared, and it was much darker than it had been some hours before. The guide led the way with a lantern. The ascent of the cone was a very stiff piece of work; it consists of loose ashes and blocks of lava, and slopes at an angle of "45° or more" according to one writer, and of 33° according to another; probably the slope varies on different sides of the cone: we do not think that the slope much exceeds 33° anywhere on the side of the cone which we ascended. Fortunately there was no strong wind, and we did not suffer from the sickness of which travellers constantly complain in the rarefied air of the summit. We reached the highest point at 4.30 a.m., and found a temperature of 47° F.

When Sir William Hamilton ascended towards the end of June the temperature at the base of the mountain was 84° F., and at the summit 56° F. When Brydone left Catania on May 26th, 1770, the temperature was 76° F., Bar. 29 in. 8-1/2 lines; at Nicolosi at midday on the 27th it was 73° F., Bar. 27 in. 1-1/2 lines; at the Spelonca del Capriole (6,200 feet), 61° F., Bar. 26 in. 5-1/2 lines; at the foot of the crater, temp. 33° F., Bar. 20 in. 4-1/2 lines, and at the summit of the crater just before sunrise, temp. 27° F., Bar. 19 in. 4 lines.

On reaching the summit we noticed that a quantity of steam and sulphurous acid gas issued from the ground under our feet, and in some places the cinders were so hot that it was necessary to choose a cool place to sit down upon. A thermometer inserted just beneath the soil from which steam issued registered 182° F. For a short time we anxiously awaited the rising of the sun. Nearly all the stars had faded away; the vault of heaven was a pale blue, becoming a darker and darker grey towards the west, where it appeared to be nearly black. Just before sunrise the sky had the appearance of an enormous arched spectrum, extremely extended at the blue end. Above the place where the sun would presently appear there was a brilliant red, shading off in the direction of the zenith to orange and yellow; this was succeeded by pale green, then a long stretch of pale blue, darker blue, dark grey, ending opposite the rising sun with black. This effect was quite distinct, it lasted some minutes, and was very remarkable. This was succeeded by the usual rayed appearance of the rising sun, and at ten minutes to 5 o'clock the upper limb of the sun was seen above the mountains of Calabria. Examined by the spectroscope the Fraunhofer lines were extremely distinct, particularly two lines near the red end of the spectrum.

The top of the mountain was now illuminated, while all below was in comparative darkness, and a light mist floated over the lower regions. We were so fortunate as to witness a phenomenon which is not always visible, viz., the projection of the triangular shadow of the mountain across the island, a hundred miles away. The shadow appeared vertically suspended in space at or beyond Palermo, and resting on a slightly misty atmosphere; it gradually sank until it reached the surface of the island, and as the sun rose it approached nearer and nearer to the base of the mountain. In a short time the flood of light destroyed the first effects of light and shadow. The mountains of Calabria and the west coast of Italy appeared very close, and Stromboli and the Lipari Islands almost under our feet; the east coast of Sicily could be traced until it ended at Cape Passaro and turned to the west, forming the southern boundary of the island, while to the west distant mountains appeared. No one would have the hardihood to attempt to describe the various impressions which rapidly float through the mind during the contemplation of sunrise from the summit of Etna. Brydone, who is by no means inclined to be rapturous or ecstatic in regard to the many wonderful sights he saw in the course of his tour, calls this "the most wonderful and most sublime sight in nature." "Here," he adds, "description must ever fall short, for no imagination has dared to form an idea of so glorious and so magnificent a scene. Neither is there on the surface of this globe any one point that unites so many awful and sublime objects. The immense elevation from the surface of the earth, drawn as it were to a single point, without any neighbouring mountains for the senses and imagination to rest upon, and recover from their astonishment in their way down to the world. This point or pinnacle, raised on the brink of a bottomless gulph, as old as the world, often discharging rivers of fire and throwing out burning rocks with a noise that shakes the whole island. Add to this, the unbounded extent of the prospect, comprehending the greatest diversity and the most beautiful scenery in nature, with the rising sun advancing in the east to illuminate the scene."

When the sun had risen we had time to examine the crater, a vast abyss nearly 1000 feet in depth, and with very precipitous sides. Its dimensions vary, but it is now between two and three miles in circumference. Sometimes it is nearly full of lava, at other times it appears to be bottomless. At the present time it is like an inverted cone; its sides are covered with incrustations of sulphur and ammonia salts, and jets of steam perpetually issue from crevices. Near the summit we found a deposit, several inches in thickness, of a white substance, apparently lava decomposed by the hot issuing gases. Hydrochloric acid is said to frequently issue from the crater; the gases that were most abundant appeared to be sulphurous acid and steam. The interior of the crater appeared to be very similar to that of the Solfatara near Puzzuoli. During the descent from the cone we collected various specimens of ash and cinder, some red, others black and very vesicular, others crystalline, some pale pink. The steep slope of the cone was well shown by the fact that, although the surface is either extremely rugged owing to the accumulation of masses of lava, or soft and yielding on account of the depth of cinders, a large mass of lava set rolling at the top rushes down with increasing velocity until it bounds off to the level plain below.

The great cone is formed by the accumulation of sand, scoriæ, and masses of rock ejected from the crater; it is oval in form, and has varied both in shape and size in the course of centuries. When we saw it, it was not full of smoke or steam; but it was possible to see to the bottom of it, in spite of small jets of steam which issued from the sides. It presented the appearance of a profound funnel-shaped abyss; the sides of which were covered with an efflorescence of a red or yellow, and sometimes nearly white, colour. The crater presented the same appearance when it was seen by Captain Smyth in 1814, but he was so fortunate as to witness it in a less quiescent state. "While making these observations," he writes, "on a sudden the ground trembled under our feet, a harsh rumbling with sonorous thunder was heard, and volumes of heavy smoke rolled over the side of the crater, while a lighter one ascended vertically, with the electric fluid escaping from it in frequent flashes in every direction.... During some time the ground shook so violently that we apprehended the whole cone would tumble into the burning gulf (as it actually had done several times before) and destroy us in the horrible consequences; however, in less than a couple of hours all was again clear above and quiet within." When Mr. Gladstone ascended in 1838, the volcano was in a slight state of eruption: "The great features of this action," he writes, "are the sharp and loud claps, which perceptibly shook from time to time the ground of the mountain under our feet; the sheet of flame which leapt up with a sudden momentary blast, and soon disappeared in smoke; then the shower of red-hot stones and lava. At this time, as we found on our way down, lava masses of 150 or 200 pound weight were being thrown a distance of probably a mile and a half; smaller ones we found even more remote. These showers were most copious, and often came in the most rapid succession. Even while we were ascending the exterior of the cone, we saw them alighting on its slope, and sometimes bounding down with immense rapidity within, perhaps, some thirty or forty yards of our rickety footing on the mountain side. They dispersed like the sparks of a rocket; they lay beneath the moon, over the mountain, thicker than ever the stars in heaven; the larger ones ascended as it were with deliberation, and descended, first with speed and then with fury. Now they passed even over our heads, and we could pick up some newly fallen, and almost intolerably hot. Lastly, there was the black grey column, which seemed smoke, and was really ash, and which was shot from time to time out of the very bowels of the crater, far above its edge, in regular unbroken form."

At the Casa Inglesi we remounted the mules, and made a slight detour to the east in order to look down into the Val del Bove, which is here seen as a gigantic valley, bounded on the north by the precipitous cliffs of the Serra delle Concazze, and on the South by the Serra del Solfizio. It is believed by Lyell and others that in the Balzo di Trifoglietto, at which point the precipices are most profound and abrupt, there was a second permanent crater of eruption. The Torre del Filosofo, a ruined tower, traditionally the observatory of Empedocles, stands near the Casa Inglesi. Not far from this a great deposit of ice was found in 1828. It was preserved from melting by a layer of ashes and sand, which had covered it, soon after its first existence, as a glacier: a stream of lava subsequently flowed over the ashes, and completely protected the ice; the non-conducting power of the ashes prevented the lava from melting the ice. The snow which falls on the mountain is stowed away in caves, and used by the Sicilians during summer. A ship load is also sent to Malta, and the Archbishop of Catania derives a good deal of his income from the sale of Etna snow.

During our descent from the mountain we were much struck by the apparent nearness of the minor cones beneath us, and of the villages at the base of the mountain. They seemed to be painted on a vertical wall in front of us, and although from ten to fifteen miles distant they appeared to be almost within a stone's throw. This curious effect, which has often been observed before, is due to refraction. At the summit of Etna we have left one-third of the atmosphere beneath us, and the air is now pressing upon the surface of the earth with a weight of ten pounds on the square inch, instead of the usual fifteen pounds experienced at the level of the sea. In looking towards the base of the mountain we are consequently looking from a rarer to a denser medium; and it is a law of optics, that when light passes from a denser to a rarer medium it is refracted away from the perpendicular, and thus the object, from which it emanates, appears raised, and nearer to us than it really is. The objects around Etna appear near to us and raised vertically from the horizon for the same reason that a stick plunged in water appears bent.

We reached Nicolosi again about noon, having left it eighteen hours before. The ascent of the mountain, although it does not involve much hard walking, is somewhat trying on account of the extremes of temperature which have to be endured. In the course of the morning of our descent we had experienced a difference equal to more than 40° F. As to the ascent, you are moving upwards nearly all night; you have six hours of riding on a mule, some of it in a bitterly cold atmosphere; you get very much heated by the final steep climb of 1100 feet, and you find at the summit a piercing wind; of course there is no shelter, and you sit down to wait for sunrise on cinders which are gently giving off steam and sulphurous acid; the former condenses to water as soon as it meets the cold air, and you find your great coat, or the rug on which you have sat down, speedily saturated with moisture.