¯\_(ツ)_/¯
Everard Digby, A Short Introduction for to Learne to Swimme (1587)
“The times which the temperature of this our climate affords as good to swimme in, is comprehended in foure monethes, May, Iune, Iuly, and August... thence commeth a more vehement heate, which dooth temperate the water, and make wholesome the ayre... In the place is two things especially to be respected, first, that the bancks bee not ouergrowen with ranck thicke grasse, where oft-times, doe lie and lurke many stinging Serpents, and poisoned Toades: not full of thornes, bryers, stubbes, or thistles, which may offend the bare feete... Next that the water it selfe bee cleare, not troubled with any kinde of slymie filth, which is very infectious to the skin... Also that there be not in the bottome of the Riuer any olde stakes or sharpe stones, which may greatly indaunger the Swimmer... let him associate himselfe with some one that is taller and stronger then himself, which may both comfort him, and helpe to sustaine him, for that at the first enterance, the chilnes of the water will greatly discomfort him.”
Everard Digby, A Short Introduction for to Learne to SwimmeA few rules for summer swimming fun: avoid poisoned toads, and don't forget to bring a muscular friend to comfort you in case the water is cold.