On Architecture

Vitruvius Pollio

Vitruvius Pollio, creator; Morgan, M. H. (Morris Hicky), 1859-1910, translator

1. THERE are, however, some hot springs that supply water of the best taste, which is so delightful to drink that one does not think with regret of the Fountain of the Muses or the Marcian aqueduct. These hot springs are produced naturally, in the following manner. When fire is kindled down beneath in alum or asphalt or sulphur, it makes the earth immediately over it very hot, and emits a glowing heat to the parts still farther above it, so that if there are any springs of sweet water found in the upper strata, they begin to boil in their fissures when they are met by this heat, and so they run out with their taste unimpaired.

2. And there are some cold springs that have a bad smell and

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taste. They rise deep down in the lower strata, cross places which are on fire, and then are cooled by running a long distance through the earth, coming out above ground with their taste, smell, and colour spoiled; as, for instance, the river Albula on the road to Tivoli and the cold springs of Ardea, which have the same smell and are called sulphur springs, and others in similar places. Although they are cold, yet at first sight they seem to be hot for the reason that when they happen upon a burning spot deep down below, the liquid and the fire meet, and with a great noise at the collision they take in strong currents of air, and thus, swollen by a quantity of compressed wind, they come out at the springs in a constant state of ebullition. When such springs are not open but confined by rocks, the force of the air in them drives them up through the narrow fissures to the summits of hills.

3. Consequently those who think that they have excavated sources of springs at the height of such hills find themselves mistaken when they open up their excavations. Suppose a bronze vase filled not to the very lips, but containing two thirds of the quantity of water which forms its capacity, and with a cover placed upon it. When it is subjected to a very hot fire, the water must become thoroughly heated, and from the rarity of its nature it greatly expands by taking in the heat, so that it not only fills the vase but raises its cover by means of the currents of air in it, and swells and runs over. But if you take the cover off, the expanding forces are released into the open air, and the water settles down again to its proper level. So it is with the sources of springs. As long as they are confined in narrow channels, the currents of air in the water rush up in bubbles to the top, but as soon as they are given a wider outlet, they lose their air on account of the rarity peculiar to water, and so settle down and resume their proper level.

4. Every hot spring has healing properties because it has been boiled with foreign substances, and thus acquires a new useful quality. For example, sulphur springs cure pains in the sinews,

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by warming up and burning out the corrupt humours of the body by their heat. Aluminous springs, used in the treatment of the limbs when enfeebled by paralysis or the stroke of any such malady, introduce warmth through the open pores, counteracting the chill by the opposite effect of their heat, and thus equably restoring the limbs to their former condition. Asphaltic springs, taken as purges, cure internal maladies.