[38] for whatever they touch slips away from them, and whatever thing they seek to take their stand on does not remain, so that they of necessity fall before they stand, like that hydrostatic machine called the helix; for in the middle of that engine there are some steps, which the husbandman when he desires to water his fields mounts up upon, but is rolled round of necessity; and in order to avoid falling he is continually catching at the nearest firm thing that he can lay his hands on, which he takes hold of and so supports his whole body; for instead of his hands he uses his feet, and instead of his feet he uses his hands; for he stands on his hands, by means of which, actions are usually done, and he acts with his feet on which it is natural to stand.