Viens no iemesliem, lūk , kāpēc izvēloties vietu, kur celt jaunu būvi, jāpiesargās, lai tuvumā nebūtu purvu:
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"[..]without marshes in the neighbourhood. For when the morning breezes blow toward the town at sunrise, if they bring with them mists from marshes and, mingled with the mist, the poisonous breath of the creatures of the marshes to be wafted into the bodies of the inhabitants, they will make the site unhealthy."
(Vitruvius, Ten books on Architecture, Book I, Chapter IV)
