The Czar also funded the work of Constantin von Tischendorf in finding the Codex Sinaiticus at the Saint Catherine's Monastery at the foot of Mount Sinai. The Czar's brother, the Grand Duke Constantine, and his wife the Princess Alexandra toured the area at this time. Significantly it was also around this period that Bishop Euspensy began missionary work in the area (his detractors claim he was a czarist agent with a scheme of wresting the Jerusalem patriarchate away from the church's liturgical twin, the Greek Orthodox Church.). Euspensy's efforts did not produce much but a few Christian Arab converts switching from the GOC to the ROC.