Two accidents took place on the London Brighton and South Coast Railway (LBSCR) during the early 1850s due to signalling failures.

The first interlocked signalling system was installed at the Bricklayers Arms junction, near the Old Kent Road in South London.

[3][4] In 1861 Saxby left the railway employment and started his own business at Haywards Heath to manufacture signalling apparatus.

"Saxby and Farmer" became the leading manufacturers of railway signalling equipment and established a works at Kilburn where they eventually employed 3,000 workers.

Saxby and Farmer became the major contractor responsible for building signal boxes on behalf of railways.