William Thaw Sr.

William Thaw was the seventh child of John and Elizabeth Thaw. He attended the Western University of Pennsylvania, now the University of Pittsburgh, and worked as a clerk in his father's bank. In 1841 he married Eliza Burd Blair (1822-1863) from Washington, Pa., who was a graduate of Dickinson College and the University of Pennsylvania. In 1842, William Thaw went into business with his brother-in-law, Thomas Shields Clarke, and established Clarke and Thaw, a transport line of canal boats and steamships known as the Pittsburgh and Cincinnati Packet Line. Clarke and Thaw entered the railroad industry in the 1850's by handling shipments of consigned goods over two or more railroad lines for the Pennsylvania Railroad Company. Thaw soon developed a freight transport service called the Star Union Line which he directed until 1873. In 1868, William Thaw and George W. Cass formed the Continental Improvement Company which helped to complete the Grand Rapids and Indiana Railroad. Around the same time, Thaw was involved in the Western Transportation Company which organized the building and operation of the Pittsburgh and Stuebenville Railroad. In 1870, The Pennsylvania Company was formed to manage and operate all western routes of the Pennsylvania Railroad and William Thaw served as its first Vice President. Thaw also served as Vice President of the Pittsburgh, Cincinnati and St. Louis Railroad and was Director for the Pennsylvania Railroad Company from 1881 to 1889. In 1873, Thaw developed and served as President of the first steamship line between the United States and Europe known as the Red Star Line. In addition to his varied business interests, William Thaw was dedicated to many civic projects and contributed significantly to the Western University and helped to build the Allegheny Observatory in 1860. Thaw was also an active member and contributor to the Third Presbyterian Church of Pittsburgh. William Thaw died in Paris in 1889.

William Thaw had five children by his first wife, Eliza Burd Blair, and five by his second wife, Mary Copley Sibbett, who Thaw married in 1867. His children were: Eliza, William, Mary, Benjamin, Alexander Blair, Henry (Harry) Kendall, Edward, Josiah Copley, Margaret, and Alice Cornelia. After William Thaw's death in 1889, Mary Copley Thaw moved to "Lyndhurst", a mansion in Pittsburgh's Squirrel Hill neighborhood.