Book 8
5.1
ONE demanded a reason why the sailors take up the water for their occasions out of the river Nile by night, and not by day. Some thought they feared the sun, which heating the water would make it more liable to putrefaction. For every thing that is heated or warmed becomes more easy to be changed, having already suffered when its proper quality was remitted. And cold constipating the parts seems to preserve every thing in its natural state, and water especially. For that the cold of water is naturally constringent is evident from snow, which keeps flesh from corrupting a long time. And heat, as it destroys the proper quality of other things, so of honey, for it being boiled is itself corrupted, though when raw it preserves other bodies from corruption. And that this is the cause, I have a very considerable evidence from standing pools; for in winter they are as wholesome as other water, but in summer they grow bad and noxious. Therefore the night seeming in some measure to resemble the winter, and the day the summer, they think the water that is taken up at night is less subject to be vitiated and changed.
