Complete Story of the San Francisco Horror

by Richard Linthicum; Samuel Fallows; Trumbull White

For two hundred years the igneous forces beneath Krakatoa remained dormant; but in September, 1880, premonitory shocks of earthquake were heard in the neighborhood. At length the inhabitants of Batavia and Bintenzorg were startled on May 20, 1883, by booming sounds which came from Krakatoa, one hundred miles distant. A mail steamer passing through the strait, had her compass violently agitated. Next day a sprinkling of ashes was noticed at some places on each side of the strait, and toward evening a steam-column rising from Krakatoa revealed the locality of the disturbance. The commander of the German war ship Elisabeth, while passing, estimated the dust-column to be about thirty-six thousand feet, or seven miles high.

Volcanic phenomena being common to that region, no fears were entertained by the inhabitants in the vicinity; and an excursion party even started from Batavia to visit the scene of action. They reached the island on May 27th, and saw that the cone of Perborwatan was active, and that a column of vapor arose from it to a height of not less than ten thousand feet, while lumps of pumice were shot up to about six hundred feet. Explosions occurred at intervals of from five to ten minutes, each of these outbursts uncovering the liquid lava in the vent, the glow of which lighted up the overhanging steam-cloud for a few seconds.

Shortly after this visit the activity diminished. But on June 19th it was noticed at Anjer that the height of the dust and vapor-column, and likewise the explosions were again increasing. On the 24th a second column was seen rising. At length, Captain Ferzenaar, chief of the Topographical Survey of Bantam, visited Krakatoa island on August 11th. He found its forests destroyed, and the mantle of dust near the shores was twenty inches thick. Three large vapor-columns were noted, one marking the position of the crater of Perborwatan, while the other two were in the center of the island, and of the latter, one was probably Danan. There were also no less than eleven other eruptive foci, from which issued smaller steam-columns and dust. This was the last report prior to the great paroxysm.

During the next two or three weeks there was a decline in the energy of the volcano, but on the afternoon of Sunday, August 26th, and all through the following night, it was evident that the period of moderate eruptive action had passed, and that Krakatoa had now entered upon the paroxysmal stage. From sunset on Sunday till midnight the tremendous detonations followed each other so quickly that a continuous roar may be said to have issued from the island. The full terrors of the eruption were now approaching. The distance of ninety-six miles from Krakatoa was not sufficient to permit sleep to the inhabitants of Batavia. All night volcanic thunders sounded like the discharges of artillery at their very doors. On the next morning there were four mighty explosions. The third was of appalling violence, and it gave rise to the most far-reaching effects. The entire series of grand phenomena at that spot extended over a little more than thirty-six hours.

Captain Thompson, of the Media, then seventy-six miles northeast of Krakatoa, saw a black mass like smoke rising into the clouds to an altitude estimated at not less than seventeen miles. The eruption was also viewed by Captain Wooldridge at a distance of forty miles. He speaks of the vapory mass looking like “an immense wall, with bursts of forked lightning, at times like large serpents rushing through the air.” After sunset this dark wall resembled “a blood-red curtain with the edges of all shades of yellow, the whole of a murky tinge, with fierce flashes of lightning.” Two other masters of vessels, at about the same distance from the volcano, report seeing the mastheads and yardarms of their ships aglow with electric fire. Such effects seem to be easily explicable. When we consider how enormous must be the friction going on in the hot air, through the clash against each other of myriads of particles of volcanic dust, during ejection and in their descent, it is evident that such friction is adequate to produce a widespread electrical disturbance in the surrounding atmosphere. The rush of steam through craters or other fissures would also contribute to these disturbances.

From these causes the compasses of passing ships were much disturbed. And yet the fall of magnetic oxide of iron (magnetite), a constituent of volcanic ash, possibly had some share in creating these perturbations. On the telephone line from Ishore, which included a submarine cable about a mile long, reports like pistol shots were heard. At Singapore, five hundred miles from Krakatoa, it was noted at the Oriental Telephone Company’s station that, on putting the receiver to the ear, a roar like that of a waterfall was heard. So great was the mass of vapor and dust in the air, that profound darkness, which lasted many hours, extended even to one hundred and fifty miles from the focus of the eruption. There is the record, among others, that it was “pitch dark” at Anjer at two o’clock in the afternoon of the 26th.

So great, too, was the ejective force that the fine volcanic dust was blown up to a height of fifty thousand feet, or over nine miles, into space. Another estimate gives the enormous altitude of seventeen miles to which the dust had been blown. The volcanic ash, which fell upon the neighboring islands within a circle of nine and one half miles radius, was from sixty-five to one hundred and thirty feet thick. At the back of the island the thickness of the ash beds was from one hundred and ninety-five to two hundred and sixty feet. Masses of floating pumice encumbered the strait. The coarser particles of this ash fell over a known area equal to 285,170 square miles, a space equal to the whole of the New England States, New York, New Jersey, Pennsylvania, Ohio, Indiana and Illinois. It is calculated that the matter so ejected must have been considerably over a cubic mile in volume.

Another distinguishing feature of this display of nature’s powers was the magnitude and range of the explosive sounds. Lloyd’s agent at Batavia, ninety-four miles distant from Krakatoa, reported that on the morning of the 27th the reports and concussions were simply deafening. At Carimon, Java, which is three hundred and fifty-five miles distant, the natives heard reports which led them to suppose that a distant ship was in distress; boats put off for what proved to be a futile search. The explosions were heard not only all over the province of Macassar, nine hundred and sixty-nine miles from the scene of the eruption, but over a yet wider area. At a spot one thousand one hundred and sixteen miles distant—St. Lucia bay, Borneo—some natives heard the awful sound. It stirred their consciences, for, being guilty of murder, they fled, fearing that such sounds signified the approach of an avenging force. Again, in the island of Timor, one thousand three hundred and fifty-one miles away, the people were so alarmed that the government sent off a steamer to seek the cause of the disturbance.

At that time, also, the shepherds on the Victoria plains, West Australia, thought they heard the firing of heavy artillery, at a spot one thousand seven hundred miles distant. At midnight, August 26th, the people of Daly Waters, South Australia, were aroused by what they thought was the blasting of a rock, a sound which lasted a few minutes. “The time and other circumstances show that here again was Krakatoa heard, this time at the enormous distance of two thousand and twenty-three miles.” And yet there is trustworthy evidence that the sounds were heard over even greater distances. Thundering noises were heard at Diego Garcia, in the Chagos islands, two thousand two hundred and sixty-seven miles from Krakatoa. It was imagined that some vessel must be in distress, and search was accordingly made. But most remarkable of all, Mr. James Wallis, chief of police in Rodriguez, across the Indian ocean, and nearly three thousand miles away from Krakatoa, made a statement in which he said that “several times during the night of August 26th-27th reports were heard coming from the eastward like the distant roar of heavy guns. These reports continued at intervals of between three and four hours.” Obviously, some time was needed for the sounds to make such a journey. On the basis of the known rate of velocity, they must have been heard at Rodriguez four hours after they started from their source.

And yet, great as was the range of such vibrations, they could not be compared with that of the air-wave caused by the mighty outburst. This atmospheric wave started from Krakatoa at two minutes past ten on that eventful Monday morning, moving onward in an ever-widening circle, like that produced when a stone is thrown into smooth water. This ring-like wave traveled on at the rate of from six hundred and seventy-four to seven hundred and twenty-six miles an hour, and went around the world four, if not even seven times, as evidenced by the following facts: Batavia is nearly a hundred miles from the eruptive focus under review. There was connected with its gas-holder the usual pressure recorder. About thirteen minutes after the great outburst, this gauge showed a barometric disturbance equal to about four-tenths of an inch of mercury, that is, an extra air pressure of about a fifth of a pound on every square inch. The effects on the air of minor paroxysmal outbreaks are also recorded by this instrument; but barometers in the most distant places record the same disturbance. The great wave passed and repassed over the globe and no inhabitant was conscious of the fact. Barometers in the principal cities of the world automatically recorded this effect of the first great wave from Krakatoa to its antipodes in Central America, and also the return wave. The first four oscillations left their mark on upward of forty barograms, the fifth and sixth on several, and at Kew, England, the existence of a seventh was certainly established.