[Footnote 117: In its long progress to Mosul, Jerusalem,
Rome, &c., the story of Prester John evaporated in a
monstrous fable, of which some features have been borrowed
from the Lama of Thibet, (Hist. Genealogique des Tartares,
P. ii. p. 42. Hist. de Gengiscan, p. 31, &c.,) and were
ignorantly transferred by the Portuguese to the emperor of
Abyssinia, (Ludolph. Hist. Aethiop. Comment. l. ii. c. 1.)
Yet it is probable that in the xith and xiith centuries,
Nestorian Christianity was professed in the horde of the
Keraites, (D'Herbelot, p. 256, 915, 959. Assemanni, tom.
iv. p. 468 - 504.) ]