A set of 50 photographs and associated handwritten descriptive notes, acquired from the Imperial Russian Geographical Society in St. Petersburg. The complete notes, "1904 View of Great Tibet", are available at: http://collections.lib.uwm.edu/u?/tibet,94
"Obo is a Mongolized Tibetan word, do bong, 'pile of stones' or do bum 'ten myriad stones'." They are found all over Mongolia and Tibet. In many countries shepherds put up small ones as guides to take their flocks to water, or to go to camp."
Rockhill, W.W. (1891). The land of lamas. New York: Century.
Google Books at: http://books.google.com/books?id=tNkMAAAAIAAJ&pg=PA1&dq