Harper's Round Table, January 5, 1897

by Various

In endeavoring to set before the reader an account of volcanoes, I find a difficulty arising from the fact that very few people have had a chance to see these curious features in the machinery of the earth. In the United States, except in the far-away island district of Alaska, there is not one that has been seen by white men in a state of activity. Many, it is true, exist in the Cordilleran district, between the Canadian and Mexican line, but these are for the most part inaccessible, or, if conveniently placed for the tourists' convenience, are not well suited to show the most important facts of these structures. In writing about the sea, rivers, mountains, glaciers, or any other class of natural objects, our country affords admirable means of illustration, which may serve to convey clear impressions; but the story of volcanoes has to be told without this help.

It is otherwise in the Old World. In Europe, Ætna and Vesuvius have had their activity associated with that of the most cultivated people of the world for about twenty-five centuries; and at many points, as in the valley of the Po or in central France, there are groups of volcanoes which are, though no longer active, in a very perfect state of preservation, within sight of the ways which are traversed by all sight-seeing travellers.

Its convenient position, immediately neighboring to the most beautiful scenery and the greatest treasures of antiquity, has made Vesuvius the volcano of all others which people are likely to see. Probably a hundred climb it for one who ascends any other cone. This is true of our own countrymen who travel as well as those of Europe. This choice of Vesuvius as the volcano of pilgrimage is fortunate, for the reason that though by no means a great specimen of its kind, it is perhaps the most useful to the student of all the thousands that have been examined and described by observers of volcanic phenomena. Therefore, as we should begin our inquiry by seeing what occurs in a volcanic outbreak, and the consequences of these explosions, we will make our study on this beautiful cone.

It is characteristic of this most amiable of volcanoes that of late years it has been in many frequent slight eruptions. The greater number of craters lie sleeping for hundreds or perhaps thousands of years, until they break forth with a fury that sends desolation to the country for miles from the point where the discharge takes place. But Vesuvius, which in its early years was given to furious storms, such as that which overwhelmed Herculaneum and Pompeii eighteen centuries ago, has now become so mild-mannered that men till their vineyards in a fearless way on the slopes which lead up to the crater.

It was my good fortune, about fifteen years ago, on one of several visits to Vesuvius, to find it in an excellent state for an inquiry, which showed me more of what goes on in an eruption, and led to a better insight into the nature of the work than has often been seen by the geologist. There was a slight eruption in progress during the night; from the windows of my lodging in Naples I could see the successive puffs of fire from the crater coming regularly, several each minute. On the following morning there was a strong northerly wind blowing, which made me hope it would be possible to approach the edge of the opening without danger from the falling stones.

Climbing the long way which leads from the railway station on the shores of the bay, through the gardens, villages, and vineyards, I came at length to the observatory which has been established on the border of the area which is reasonably safe in times of trouble. Here I learned that the instruments which show the tremblings of the earth, the small earthquakes which are not perceived by our bodies, indicated that the cone was in a state of constant trembling. The observers who watch this apparatus thought it likely that some time during the day the cone would be blown away in a violent eruption, such as now and then sends the upper part of this and many other volcanoes flying into bits before the fierce blast of the escaping vapors.

My way lay across a wide field of lava and cinders to the place where the steep slope of the upper cone rose to the level where the crater was bombarding the sky with the rapidity of a well-served cannon. The climb up this cone, composed of the bits of lava which had been blown into the air and had fallen down again to the earth, was very laborious. The slope was as steep as a house roof. It took three steps to gain each foot in height. Now and then a stronger blast from the crater would shake the heap, so that it was hard to keep the ground that had been gained. It took a long hour to win the height of four or five hundred feet.

"CREEPING TO THE SHARP EDGE OF THE CRATER, I SAW INTO THE VERY MOUTH OF THE VOLCANO."

Creeping to the sharp edge of the crater, and peering cautiously into the cavity, I saw into the very mouth of the volcano. The cup-shaped depression was about three hundred feet in diameter, and perhaps half that depth; it passed downward into a well-like pipe, perhaps sixty feet across. The lower part of the pit was, even in the bright sunlight, evidently red-hot. The sides of the pipe were white-hot. On this lower part of the pit, which shone like the eye of a furnace, a mass of very fluid lava was lashing up and down, now rising until it filled the bottom of the basin with its fiery tide, again sinking until it was out of sight.