Edinburgh, Montreal, USA George Leonard Howden

I am trying to find what happened to my grandfather George Leonard Howden born in Edinburgh and believed to have lived in Montreal and the USA He was in Edinburgh Scotlandin 1903 and 1906. My mother was his eldest daughter Jemima Ann Seaton Howden born 1903. Despite intensive research at the Scottish Records Office I have been unable to find a record of my grandfathers death. Any information would be gratefully appreciated. My email address is HKennedy309@aol.com