Note 7 — Chapter I · FROM CHʽANG-GAN TO THE SANDY DESERT.
James Legge translation
Under varshâs or vashâvasâna (Pâli, vassa; Spence Hardy, vass), Eitel (p. 163) says:—‘One of the most ancient institutions of Buddhist discipline, requiring all ecclesiastics to spend the rainy season in a monastery in devotional exercises. Chinese Buddhists naturally substituted the hot season for the rainy (from the 16th day of the 5th to the 15th of the 9th Chinese month).’