<P> The Kean priests of Zeus as Rainmaker and Lord of Moisture observed annual sacrifices before the rise of Sirius to prevent scorching drought . This practice was credited to the culture hero Aristaeus . Aristotle mentions the proverbial heat of the dog days as part of his argument against an early formulation of evolution in his Physics . </P> <P> The Romans continued to blame Sirius for the heat of the season and attendant lethargy and diseases . In his Georgics, Vergil notes vintners' efforts to protect their work during the time "when the Dog - star cleaves the thirsty Ground". Seneca's Oedipus complains of "the scorching dog - star's fires". Pliny's Natural History notes an increase in attacks by dogs during July and August, and advises feeding them chicken manure to curb the tendency . In the early 20th century, historians still noted the "discouraging heat" and "oppression" of the dog days of the Roman summer . </P> <P> The period has long featured in western medicine . The 1564 English Hope of Health counseled that purging (bloodletting and induced vomiting) should be avoided during the "Dogge daies" of summer because "the Sunne is in Leo" and "then is nature burnt vp & made weake". The 1729 British Husbandman's Practice claimed that "The Heat of the Sun is so violent that Men's bodies at Midnight sweat as at Midday: and if they be hurt, they be more sick than at any other time, yea very near Dead". It therefore advised men to "abstain all this time from women" and to "take heed of feeding violently". In the 1813 Clavis Calendria, the dog days are a time wherein "the Sea boiled, the Wine turned sour, Dogs grew mad, Quinto raged with anger, and all other creatures became languid; causing to man, among other diseases, burning fevers, hysterics, and phrensies". </P> <P> Even after astrology and its influence on health and agriculture waned in importance, the "dog days" continues to be vaguely applied to the hottest days of the summer, with its attendant effects on nature and society . In North America, it became proverbial among farmers that a dry growing season through the dog days was preferable to the trouble of a wet one: </P>

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