By Karen Lee Ziner Providence Journal photo / Frieda Squires Walton in 2010 Richard J. Walton, an iconic figure in Rhode Island known for his social and political activism, including longstanding affiliations with Amos House and the Stone Soup Coffeehouse, has died. Walton's daughter, Cathy Barnard of Simsbury, Ct., said Walton died Thursday of leukemia at Rhode Island Hospital. In his trademark bib overalls and bandana, Walton was a fixture at local anti-nuclear and peace vigils for years.