My house has field stone basement walls that are about 2 feet thick. The mortar between the rocks is crumbling and falling onto the basement floor. It is a constant mess to clean up. So far the rocks seem to stay in place, just the mortar between the rocks is coming loose.
The house is located in Wisconsin and was built in 1855. It was Calumet County's first courthouse.
Some one told me that the walls need to be re-tucked, but I think that will only be a temporary and expensive solution. I can't beleive that someone doesn't make a product that you could spray onto the walls to hold the grout in, like the stuff they spray into gas tanks to plug leaks.