CHAP. 26.—THE METHOD OF SEARCHING FOR WATER.
It will not be out of place to append here an account of the method employed in searching for water. Water is mostly to be found in valleys, whether formed by the intersection of declivities or lying at the lower part of mountains. Many persons have been of opinion that all places with a northern[3047] aspect are naturally provided with water: a point upon which it will not be amiss to explain the diversities presented to us by Nature. On the south side of the mountains of Hyrcania it never rains; and hence it is that it is only on the north-east side that they are wooded. As for Olympus, Ossa, Parnassus, the Apennines, and the Alps, they are covered with wood on every side, and abundantly watered with streams. Some mountains, again, are wooded on the south side, the White[3048] Mountains in Crete, for example. On this point, therefore, we may come to the conclusion that there is no rule which in all cases holds good.
CHAP. 27.—SIGNS INDICATIVE OF THE PRESENCE OF WATER.
The following are indications of the presence of water:—rushes, reeds, the plant mentioned with reference to this point already,[3049] or frogs sitting squatted on a spot for a long time together. As to the wild[3050] willow, alder, vitex, reed, and ivy, all of which grow spontaneously on low grounds in which there is a settling of rain water from higher localities, considered as indications of the presence of water, they are all[3051] of them of a deceptive nature. A sign much more to be depended upon, is a certain misty exhalation, visible from a distance before sunrise. The better to observe this, some persons ascend an eminence, and lie flat at full length upon the ground, with the chin touching the earth. There is also another peculiar method of judging upon this point, known only to men of experience in these matters: in the very middle of the heats of summer they select the hottest hours of the day, and observe how the sun’s rays are reflected in each spot; and if, notwithstanding the general dryness of the earth, a locality is observed to present a moist appearance, they make no doubt of finding water there.
But so intense is the stress upon the eyes in doing this, that it is very apt to make them ache; to avoid which inconvenience, they have recourse to other modes of testing. They dig a hole, for instance, some five feet in depth, and cover it with vessels of unbaked pottery, or with a copper basin well-oiled; they then place a burning lamp on the spot, with an arch-work over it of leaves, and covered with earth on the top. If, after a time, they find the pots wet or broken, the copper covered with moisture, or the lamp extinguished, but not from want of oil, or if a lock of wool that has been left there is found to be moist, it is a sign of the presence of water, beyond all doubt. With some persons it is the practice to light a fire on the spot before they dig the hole, a method which renders the experiment with the vessels still more conclusive.
CHAP. 28.—DIFFERENCES IN WATERS, ACCORDING TO THE NATURE OF THE SOIL.
The soil itself, too, gives indications of the presence of water, by presenting white spots, or an uniformly green appearance: for where the stratum is black the springs are mostly not of a permanent nature. The presence of potter’s clay always puts an end to all hopes of finding water, and the excavation is immediately abandoned; an eye being carefully kept to the strata[3052] of the earth, to see whether, beginning with black mould, it successively presents the appearances above-mentioned. The water is always fresh that is found in argillaceous soils, but in a stratum of tufa it is colder than elsewhere; this, indeed, being a soil which is highly approved of, as having a tendency to make the water pure and extremely light to the stomach, and, by its action as a filter, to withhold all impurities. The presence of sand[3053] gives indications of springs of but limited extent, and of water impregnated with slime; while that of gravel announces the presence of water of excellent flavour, but not to be depended upon for permanence. Male[3054] sand, fine sea[3055]-sand, and charcoal[3056] earth, yield a constant supply of water of a highly wholesome quality; but it is the presence of red stones that is the most to be depended upon, and the water found there is of the very finest quality. Craggy localities at the foot of mountains, and silicious soils, are equally good; in addition to which, the water found there is cooler than elsewhere.
In boring for water, the soil should always become more and more humid, and, the deeper the descent, with the greater facility the implements should penetrate. In deep-sunk wells, the presence of sulphureous[3057] or aluminous substances is fatal to the sinkers; a danger that may be guarded against by letting down a lighted lamp, and ascertaining whether the flame is extinguished. When such is found to be the case, it is the practice to sink vent-holes on each side of the well, both right and left, in order to receive and carry off the noxious exhalations. Independently of these evils, the air becomes heavier, from the great depth merely of the excavation, an inconvenience which is remedied by keeping up a continual circulation with ventilators of linen cloth. As soon as water is reached, walls are constructed at the bottom, but without cement,[3058] in order that the springs may not be intercepted.
Some waters, the sources of which do not lie on elevated ground, are coldest at the beginning of spring, being maintained by the winter rains in fact. Others, again, are coldest at the rising of the Dog-star—peculiarities, both of them, to be witnessed at Pella in Macedonia; for in front of that city there is a marsh-spring, which at the beginning of summer is cold, while in the more elevated parts of the city the water is ice-cold[3059] in the hottest days of summer. The same is the case, too, at Chios, the water-supply of the harbour and of the city occupying the same relative positions. At Athens, the water of the Fountain Enneacrunos[3060] is colder in a cloudy summer than the well there in the garden of Jupiter; while on the other hand, this last is ice-cold during the drought of a hot summer. For the most part, however, wells are coldest about the rising of Arcturus.[3061]