Northern Ningsia (宁夏）. The Mongolian Plain begins.
1936, by Pickens Jr., Rev. Claude L.
In Picken's diary dated on June 19th Friday, he wrote"
The day of the Eclipse. 20 li from where we stayed the night we
saw a chortan, rather dilapidated. This probably marks the border between
Ningsia and Suiyuan, though we were told the canal a li or so
away was the present one. Possibly this chortan is the ethnological
border of the Mongolian plain. This chortan having been erected to
keep the influence of the Chinese to the South. At the canal construction
work was going on to erect a motor bridge across. ...