In 1905 Richard Hornsby & Sons invented a caterpillar track for a machine using Hornsby's oil engines; these engines were developed by Yorkshireman Herbert Akroyd Stuart, from which compression-ignition principle the diesel engine evolved, being manufactured in Grantham from 8 July 1892. Although these engines were not wholly compression-ignition derived, later in 1892 a prototype high-pressure version was built at Hornsby's, developed by Thomas Henry Barton OBE – later to be the founder of Nottingham's Barton Transport, whereby ignition was achieved solely (100%) through compression; it ran continuously for six hours, being the first known diesel engine. In the town, Hornsby's built Elsham House (the grounds became Grantham College) and the Shirley Croft. Their site on Houghton Road was bought from Lord Dysart.