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Keywords from Image Description:
Mengu Ziyun xia b. Artwork Zhu Zongwen en Across the top of the page are Old Mandarin syllables disregarding tone tsim tshim sim zim shim zhim im xim yim and lim each written vertically in 'Phagspa script Beneath each syllable is list of characters with that pronunciation grouped by tone and Institution British Library London