yada mesa-tulayor vartate tadaho-ratrani samanani bhavanti yada vrsabhadisu pancasu ca rasisu carati tadahany eva vardhante hrasati ca masi masy ekaika ghatika ratrisu.
yada—when; mesa-tulayoh—in Mesa (Aries) and Tula (Libra); vartate—the sun exists; tada—at that time; ahah-ratrani—the days and nights; samanani—equal in duration; bhavanti—are; yada—when; vrsabha-adisu—headed by Vrsabha (Taurus) and Mithuna (Gemini); pancasu—in the five; ca—also; rasisu—signs; carati—moves; tada—at that time; ahani—the days; eva—certainly; vardhante—increase; hrasati—is diminished; ca—and; masi masi—in every month; eka-eka—one; ghatika—half hour; ratrisu—in the nights.
When the sun passes through Mesa [Aries] and Tula [Libra], the durations of day and night are equal. When it passes through the five signs headed by Vrsabha [Taurus], the duration of the days increases [until Cancer], and then it gradually decreases by half an hour each month, until day and night again become equal [in Libra].
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