File:Cincinnati Mound Street Temple.jpg|
The Hemingray 42, a telegraph insulator produced by the Hemingray Glass Company, is widely found in North America.
The Hemingray Glass Company was a glass company founded in Cincinnati, Ohio, in the mid-nineteenth century.
In 1848, Robert Hemingray and Ralph Gray established a glass company in Cincinnati. It is unclear what the company was named at its founding, but by 1857, the firm was known as Gray, Hemingray, & Bros. The company made numerous glass products, including salt and pepper shakers, dishware, and various knick-knacks, but it became especially well known for glass insulators, which were needed in the telegraph and eventually the telephone industries.
The company remained in Cincinnati only until 1852, when it relocated across the Ohio River to Covington, Kentucky. Many Cincinnati residents continued to find employment in the firm. With Ralph Gray's death in 1863, the company was renamed Hemingray, Bros., & Co. in 1864, and then as R. Hemingray & Co. in 1868. Finally, in 1870, the company adopted the name Hemingray Glass Company.
The firm grew relatively quickly in the years after the American Civil War. In 1888, Hemingray Glass Company opened a plant in Muncie, Indiana, effectively closing its manufacturing facility in Covington. In 1892, a fire closed temporarily the Muncie plant, causing Hemingray Glass Company to reopen the Covington establishment until the firm completed repairs in Muncie. Hemingray Glass Company remained as a separate entity until 1933, when Owens-Illinois Glass Co. purchased the firm. Known as the Hemingray Division of the Owens-Illinois Glass Co., the Muncie plant remained in operation until 1972.