Recorded in Gong Zizhen's
龚自珍 essay 《
正魏译》 (Qing dynasty). The phrase literally describes the physical form of early Buddhist texts:
梵 = Sanskrit,
贝叶 = the dried, treated leaves of the Talipot palm (Corypha umbraculifera) on which monks in India inscribed sutras with iron styluses before paper reached the subcontinent.
