Also in 1894, Thornton began his career in the railroad business, entering as a draftsman of the Pennsylvania Railroad

Pennsylvania Railroad

The Pennsylvania Railroad was an American Class I railroad, founded in 1846. Commonly referred to as the "Pennsy", the PRR was headquartered in Philadelphia, Pennsylvania....

. He was based in the Pittsburgh office. He was promoted to supervisory engineer in 1899 and District Superintendent in 1901. As he climbed rapidly through the PRR hierarchy, he became a favorite of the management and workers alike, enjoying immense popularity. In 1912 he was again promoted, being named General Superintendent of the Long Island Rail Road

Long Island Rail Road

The Long Island Rail Road or LIRR is a commuter rail system serving the length of Long Island, New York. It is the busiest commuter railroad in North America, serving about 81.5 million passengers each year. Established in 1834 and having operated continuously since then, it is the oldest US...

.
In 1914, when Great Britain

Great Britain

Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...

 was looking for a manager to modernize its Great Eastern Railway

Great Eastern Railway

The Great Eastern Railway was a pre-grouping British railway company, whose main line linked London Liverpool Street to Norwich and which had other lines through East Anglia...

, Henry W.