lead. A metallic element, atomic no. 82, atomic wt. 207.2; occurs in nature as an oxide or one of the salts, but chiefly as the sulfide, or galena; 210 Pb (half-life equal to 22.6 years) has been used in the treatment of certain eye conditions.ead. A metallic element, atomic no. 82, atomic wt. 207.2; occurs in nature as an oxide or one of the salts, but chiefly as the sulfide, or galena; 210 Pb (half-life equal to 22.6 years) has been used in the treatment of certain eye conditions.
Revillo, South Dakota. (Redirected from Revillo, SD) Revillo is a town in Grant County, South Dakota, United States. The population was 119 at the 2010 census. The name of the town most likely was derived from a backwards spelling of the proper name Olliver.
Gregory County, South Dakota. Gregory County is a county located in the U.S. state of South Dakota. As of the 2010 census, the population was 4,271. Its county seat is Burke. The county was created in 1862 and organized in 1898. It was named for the politician J. Shaw Gregory.