On March 1, 1873, Eureka County, Nevada, was created fom the eastern part of Lander county, after silver was discovered in the area. To do any county business, they had to travel to Austin,which was over 100 miles away, so a new county was created for the boom that the mining had created in the area. The town of Eureka became the county seat for the Eureka County. Originally, this is where Thomas Rosevear lived when he first arrived in the United States. By the 1880 census he had moved to South Ruby Hill, which was closer to the mine, but was still in the Eureka County. There were quite of few miners who had emigrated from Cornwall, who were living in Ruby Hill, so he must have felt very comfortable there. I have found a journal article, Cousin Jacks of Ruby Hill, at the Family History Library, and will write more on the migration of the Cornish to this area.