At first the idea arose that this was an ancient burial-ground, and that the tombs had been hollowed out of the pumice-stone after the volcanic eruption; but it is now fully ascertained that they were built long before. The largest edifice, which has been cleared of the tufa which fills it, consists of six rooms of unequal size, the largest being about eighteen feet by fifteen; and one wall extends round a court of twenty-four feet in length, with a single entrance. The walls are built in quite a different manner from the fashion now used in the islands; they are formed of a series of irregular blocks of lava, uncut, laid together without any order; no mortar, but the interstices filled with a kind of red ashes. Between the stones, long twisted branches of the olive-tree are laid, still covered with bark, but in a very advanced state of decomposition. The wood has become nearly black, as if burnt, and falls to powder at the slightest touch. The inside of the rooms has never been whitewashed; but probably a rough coating of red earthy matter, similar to that which lies between the stones, has been put on.
At the north side there are two windows; a third and a door are found on the other sides, and several openings into the different rooms. As these were formed by pieces of wood, which have decayed, the situation of the openings is chiefly ascertained by the mass of stones that have fallen in. In every case the roof lies in the interior of the rooms, and has been formed of wood laid upon the walls in such a manner as to be sloping; whilst in the largest apartment a cylindrical block of stone buried in the floor, has evidently supported a beam of wood, from which radiated the other pieces of the roof.
The things which have been discovered in this building are numerous and varied. There are vases of pottery and lava, seeds, straw, the bones of animals, tools of flint and lava, and a human skeleton. It may be remarked that not one article of iron or bronze has been found, not even the trace of a nail in the pieces of wood which have formed the roof; the absence of metals is complete. The pottery is all well proportioned, the commonest kind consisting of yellow jars, very thick, and capable of holding many gallons. They are filled with barley, the seeds of coriander and aniseed, gray peas, and other articles which cannot be made out. The form, material, and size resemble the jars used in Greece for keeping cereals in very early though historic times. In many of the rooms, heaps of barley lie against the walls. There are smaller jars of finer ware and a brighter colour, ornamented with circular bands and vertical stripes. The colouring-matter, of a deep red, has been put on in a moist state without variety of design, being always in circles and straight lines.
Besides a double necklace and ear-rings of a woman, many articles made of obsidian, a volcanic product sometimes called volcanic glass, have been found in Therasia. These are cut, but not polished; some of a triangular form have probably been the points of arrows; others are like small knives or scrapers for preparing skins. The use of obsidian appears to have been common during the Stone age among those nations who lived in volcanic regions, and even in later periods. It is said that it is still used by the women of Peru for scissors. It was more generally in vogue before the discovery of metals than since, particularly in Greece, where arms and tools of stone disappeared after copper was found. In the strata where they are at Therasia, there is nothing of iron or bronze.
Two small rings of gold are rather remarkable; they are so small that they would not pass over a child's finger. It may be inferred that they were links of a necklace. In each there is a hole about the size of a needle's eye. Probably they had been threaded one after another on the same string, and not interlaced like the rings of a chain. The interior is hollow; and no indication of soldering can be perceived, neither does the gold seem to have any alloy of other metal. The maker had flattened the bit of native gold by hammering it to the state of a thin circular leaf, and then folding it up with the edges to the inside of the ring. As gold has never been found in Santorini or in any of the neighbouring volcanic islands, it proves that the inhabitants held communication with the continent; certain streams of Asia Minor having been celebrated in antiquity for the great quantity of gold brought down.
Geologists have endeavoured to draw out the history of the terrible event which overwhelmed these islands and their inhabitants. At the beginning of the tertiary period, Greece, united to Africa, seems to have formed part of a large marshy continent, where now flows the Mediterranean. It was inhabited by those gigantic mammifers whose bones have been largely found in Africa. Towards the close of this epoch a lowering of the land separated Europe from Africa, and gave to the Mediterranean its present configuration. An oscillation of the crust of the earth afterwards produced openings, through which igneous matter has flowed. Torrents of lava gave birth to the volcanic rocks which are to be found in Greece and the neighbouring islands, and a volcano had evidently opened in the present bay of Santorini. The hill Saint Elias, the top of which forms the culminating point of the island, was then an island composed of schist and marble. The igneous matter, cooled by contact with the water and the atmosphere, attached itself to this hill, and the whole united together, formed the space now occupied by Santorini, Therasia, and Aspronisi. Repeated layers of lava, scoria, and ashes collected during many ages when the crater which occupied the central part was gradually becoming undermined.
Volcanoes are the weak parts of the earth's crust; there is not one in full activity which does not present alternative series of increase or lessening. The cone rises gradually until by degrees it is obstructed with lava, then a sudden fall destroys it and hollows a new crater, sometimes larger and deeper than the first. Many such occurrences have been described, but none can equal in importance the gigantic fall which formed the Bay of Santorini. All the central part must have given way, and been suddenly ingulfed, leaving but a narrow border of land, through the northern part of which the sea has dashed to fill up the hollow. Instead of a mountain three thousand feet high, there is a bay of immense depth, surrounded by precipitous rocks, close to which ships can anchor.
This violent catastrophe must have taken place when man was on the island; and the event must have been sudden, since the remains prove that there was no time to move away or to displace anything in the houses. The eruption of pumice-stone has preceded the sinking of the cone, for the tufa which covers the downs is cut through by subjacent streams of lava; nor does it seem to have been preceded by any violent earthquakes, as in that case the houses found in Therasia would have been demolished and the walls no longer standing. This is remarkable, as the construction of the buildings proves that the island was subject to them; the pieces of wood inserted in the walls seeming to be for no other object than to prevent the disastrous effects of such a shaking. This custom is still in use among all the islands of the Archipelago.
From the abundance of wood used in the houses, the island must in those days have been well supplied with timber. The olive-tree grew freely, and barley was the commonest of the cereals. Probably too the climate was different. The vine does not seem to have been there; still less was it the only plant cultivated, as now, at Santorini. The population were husbandmen, understanding how to grind barley in mills and make it into bread; how to press oil from olives, to bring up cattle, and to weave stuffs. Yet the great abundance of utensils of lava, obsidian, and flint, without any metals, shews that theirs was the age of stone, when the use of metals was unknown. The blocks of stones at the angles of the house at Therasia and the column standing near, indicate considerable skill in the workmen, when the kind of tools they used is taken into consideration; whilst the vases of pottery-ware are remarkable for their elegance of form.
It only remains to consider how many years ago it is since this great eruption took place. The data are vague, but geologists have tried to make some approximation. It is well known that after any violent catastrophe the subterranean forces seem to be exhausted; the periods of repose in a volcano are proportional to the previous energy. About one hundred and ninety-six years before Christ there is the record of an eruption, which raised in the centre of the bay a small islet called Palæa Kameni. After the Christian era, frequent slight emissions only served to increase the size of the island, and during the middle ages there was a period of calm. In the fifteenth century the excitement again burst forth, raising reefs both inside and outside the bay. The second duration of rest was about ten centuries; so that to the first, according to its intensity, there may be calculated at least twice that time; thus the formation of the bay was perhaps two thousand years B.C.