Erdmann, following his reading of Rashiduddin, says Chinghiz took the cities of Tangut, called Arucki, Kachu, Sichu, and Kamichu, and besieged Deresgai (D’Ohsson, Derssekai), whilst Shidergu, the King of Tangut, betook himself to his capital Artackin.

D’Ohsson, also professing to follow Rashid, calls this “his capital Irghai, which the Mongols call Ircaya.”  Klaproth, illustrating Polo, reads “Eyircai, which the Mongols call Eyircaya.”

Petis de la Croix, relating the same campaign and professing to follow Fadlallah, i.e.  Rashiduddin, says the king “retired to his fortress of Arbaca.”

C. Sanang Setzen several times mentions a city called Irghai, apparently in Tangut; but all we can gather as to his position is that it seems to have lain east of Kanchau.

We perceive that the Arbaca of P. de la Croix, the Eyircai of Klaproth, the Uiraca of D’Ohsson, the Artacki or Artackin of Erdmann, are all various readings or forms of the same name, and are the same with the Chinese form Ulahai of De Mailla, and most probably the place is the Egrigaia of Polo.

We see also that Erdmann mentions another place Aruki ([Arabic]) in connection with Kanchau and Suhchau.  This is, I suspect, the Erguiul of Polo, and perhaps the Irghai of Sanang Setzen.

Rashiduddin seems wrong in calling Ircaya the capital of the king, a circumstance which leads Klaproth to identify it with Ning-hsia.  Pauthier, identifying Ulahai with Egrigaya, shows that the former was one of the circles of Tangut, but not that of Ning-hsia.  Its position, he says, is uncertain.  Klaproth, however, inserts it in his map of Asia, in the era of Kublai (Tabl.  Hist. pl. 22), as Ulakhai to the north of Ning-hsia, near the great bend eastward of the Hwang-Ho.  Though it may have extended in this direction, it is probable, from the name referred to in next note, that Egrigaia or Ulahai is represented by the modern principality of ALASHAN, visited by Prjevalsky in 1871 and 1872.

[New travels and researches enable me to say that there can be no doubt that Egrigaia = Ning-hsia.  Palladius (l.c. 18) says:  “Egrigaia is Erigaia of the Mongol text.  Klaproth was correct in his supposition that it is modern Ning-h’ia.  Even now the Eleuths of Alashan call Ning-h’ia, Yargai.  In M. Polo’s time this department was famous for the cultivation of the Safflower (carthamus tinctorius). [Siu t’ung kien, A.D. 1292.]” Mr. Rockhill (cf. his Diary of a Journey) writes to me that Ning-hsia is still called Irge Khotun by Mongols at the present day.  M. Bonin (J.  As., 1900.  I. 585) mentions the same fact.