In His Service ?

I was walking around the Western Graveyard in Lelant today and notices a number of the headstones had a sort of Dollar symbol with 3 crosses. My first thought was that it was something to do with the Salvation army as this graveyard although next to the parish church, was used by "Non conformists" in the 19th century i.e. anyone that wasn't Anglican. It looks like it was a bit early for that though so I did a bit more digging and it turns out it is a symbol used by many Christian faiths around this time and means IHS. There are a few theories about what this signifies, many say it originated from the Greek for the first 3 letters of Jesus, some that it stands for a Greek/Latin translation for "in this sign you will conquer" but to the Wesleyan/Methodists who seem to have used it a lot I think it came to mean "In His Service"

Has anyone else come across this in the UK ?