To these circumstances we must add those that are connected with certain celestial causes. There can be no doubt, that the Æthiopians are scorched by their vicinity to the sun’s heat, and they are born, like persons who have been burned, with the beard and hair frizzled[528]; while, in the opposite and frozen parts of the earth, there are nations with white skins and long light hair. The latter are savage from the inclemency of the climate, while the former are dull from its variableness[529]. We learn, from the form of the legs, that in the one, the fluids, like vapour, are forced into the upper parts of the body, while in the other, being a gross humour, it is drawn downwards into the lower parts[530]. In the cold regions savage beasts are produced, and in the others, various forms of animals, and many kinds of birds[531]. In both situations the body grows tall, in the one case by the force of fire, and in the other by the nutritive moisture.
In the middle of the earth there is a salutary mixture of the two, a tract fruitful in all things, the habits of the body holding a mean between the two, with a proper tempering of colours; the manners of the people are gentle, the intellect clear[532], the genius fertile and capable of comprehending every part of nature. They have formed empires, which has never been done by the remote nations; yet these latter have never been subjected by the former, being severed from them and remaining solitary, from the effect produced on them by their savage nature.
CHAP. 81. (79.)—OF EARTHQUAKES.
According to the doctrine of the Babylonians, earthquakes and clefts of the earth, and occurrences of this kind, are supposed to be produced by the influence of the stars, especially of the three to which they ascribe thunder[533]; and to be caused by the stars moving with the sun, or being in conjunction with it, and, more particularly, when they are in the quartile aspect[534]. If we are to credit the report, a most admirable and immortal spirit, as it were of a divine nature, should be ascribed to Anaximander the Milesian, who, they say, warned the Lacedæmonians to beware of their city and their houses[535]. For he predicted that an earthquake was at hand, when both the whole of their city was destroyed and a large portion of Mount Taygetus, which projected in the form of a ship, was broken off, and added farther ruin to the previous destruction. Another prediction is ascribed to Pherecydes, the master of Pythagoras, and this was divine; by a draught of water from a well, he foresaw and predicted that there would be an earthquake in that place[536]. And if these things be true, how nearly do these individuals approach to the Deity, even during their lifetime! But I leave every one to judge of these matters as he pleases. I certainly conceive the winds to be the cause of earthquakes; for the earth never trembles except when the sea is quite calm, and when the heavens are so tranquil that the birds cannot maintain their flight, all the air which should support them being withdrawn[537]; nor does it ever happen until after great winds, the gust being pent up, as it were, in the fissures and concealed hollows. For the trembling of the earth resembles thunder in the clouds; nor does the yawning of the earth differ from the bursting of the lightning; the enclosed air struggling and striving to escape[538].
CHAP. 82. (80.)—OF CLEFTS OF THE EARTH.
The earth is shaken in various ways, and wonderful effects are produced[539]; in one place the walls of cities being thrown down, and in others swallowed up by a deep cleft[540]; sometimes great masses of earth are heaped up, and rivers forced out, sometimes even flame and hot springs[541], and at others the course of rivers is turned. A terrible noise precedes and accompanies the shock[542]; sometimes a murmuring, like the lowing of cattle, or like human voices, or the clashing of arms. This depends on the substance which receives the sound, and the shape of the caverns or crevices through which it issues; it being more shrill from a narrow opening, more hoarse from one that is curved, producing a loud reverberation from hard bodies, a sound like a boiling fluid[543] from moist substances, fluctuating in stagnant water, and roaring when forced against solid bodies. There is, therefore, often the sound without any motion. Nor is it a simple motion, but one that is tremulous and vibratory. The cleft sometimes remains, displaying what it has swallowed up; sometimes concealing it, the mouth being closed and the soil being brought over it, so that no vestige is left; the city being, as it were, devoured, and the tract of country engulfed. Maritime districts are more especially subject to shocks. Nor are mountainous tracts exempt from them; I have found, by my inquiries, that the Alps and the Apennines are frequently shaken. The shocks happen more frequently in the autumn and in the spring, as is the case also with thunder. There are seldom shocks in Gaul and in Egypt; in the latter it depends on the prevalence of summer, in the former, of winter. They also happen more frequently in the night than in the day. The greatest shocks are in the morning and the evening; but they often take place at day-break, and sometimes at noon. They also take place during eclipses of the sun and of the moon, because at that time storms are lulled. They are most frequent when great heat succeeds to showers, or showers succeed to great heat[544].
CHAP. 83. (81.)—SIGNS OF AN APPROACHING EARTHQUAKE.
There is no doubt that earthquakes are felt by persons on shipboard, as they are struck by a sudden motion of the waves, without these being raised by any gust of wind. And things that are in the vessels shake as they do in houses, and give notice by their creaking; also the birds, when they settle upon the vessels, are not without their alarms. There is also a sign in the heavens; for, when a shock is near at hand, either in the daytime or a little after sunset, a cloud is stretched out in the clear sky, like a long thin line[545]. The water in wells is also more turbid than usual, and it emits a disagreeable odour[546].
CHAP. 84. (82.)—PRESERVATIVES AGAINST FUTURE EARTHQUAKES.
These same places[547], however, afford protection, and this is also the case where there is a number of caverns, for they give vent to the confined vapour, a circumstance which has been remarked in certain towns, which have been less shaken where they have been excavated by many sewers. And, in the same town, those parts that are excavated[548] are safer than the other parts, as is understood to be the case at Naples in Italy, the part of it which is solid being more liable to injury. Arched buildings are also the most safe, also the angles of walls, the shocks counteracting each other; walls made of brick also suffer less from the shocks[549]. There is also a great difference in the nature of the motions[550], where various motions are experienced. It is the safest when it vibrates and causes a creaking in the building, and where it swells and rises upwards, and settles with an alternate motion. It is also harmless when the buildings coming together butt against each other in opposite directions, for the motions counteract each other. A movement like the rolling of waves is dangerous, or when the motion is impelled in one direction. The tremors cease when the vapour bursts out[551]; but if they do not soon cease, they continue for forty days; generally, indeed, for a longer time: some have lasted even for one or two years.