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“In its stable state air is invisible, but when it is moved and condensed it becomes first wind and then cloud and then water, and finally water condensed becomes mud and stone. Rarefied air became fire, thus completing the gamut of the elements. In this way rarefaction and condensation can conjure everything out of the underlying air. In support of this claim Anaximenes appealed to experience, and indeed to experiment â€� an experiment that the reader can easily carry out for herself. Blow on your hand, First with the lips pursed, and then from an open mouth: the First time the air will feel cold, and the second time hot. This, argued Anaximenes, shows the connection between density and temperature.”