Monumental Inscription at Burstwick, Yorkshire reads:
In memory of Hannah the daughter of Matthew Abbey late of Ridgmont now of Sixverst near St. Petersburg in Russia with whom she resided in that Country eight years
but her return thither was prevented by the termination of her mortal existence on the 4th of December 1846 in the 25th year of her age.
(death cert says she died of consumption

)
Hannah was the younger sister of my direct line Mercy, who didn't go.
Matthew and his wife (also named) Mercy and a couple more children do not appear to have returned to England so think they probably died there.
Am assuming (rightly or wrongly) that Matthew worked for the "Russian Factory" at St. Petersburg.
question 1: Are there any passenger lists from England to Russia circa 1838 ?
question 2: Is there such a place a Sixverst? I've googled and googled but can't find it.
any help/pointers appreciated
Myfi