Johnson retired in 1903 and was succeeded by Richard Mountford Deeley who began as an apprentice at the works.
He carried on much where Johnson had left off, but improved the compounds with an uprated boiler and firebox, also changing the tender to a smaller six-wheeled design.
Deeley was very soon promoted to Locomotive Superintendent, with Cecil Paget as Works Manager.

In 1904 two steam motor-carriages for the Morecambe-Heysham service were fitted out at the carriage works.
Since he was also Locomotive Superintendent, he reorganised the numbering system in 1907 so that different groups of numbers were used for different classes.
Among his improvements to the works, he devised a heavy testing rig for structure testing up to 50 tons in what had developed into a dedicated Engineering Testing Department.

By 1900 some 40,000 people were employed, producing 40 new engines a year.
Electric power and lighting was installed in the Locomotive Works during 1910, supplied by the company's new generating plant located across the Derby canal at the rear of the Works.
An earlier and smaller scale electric generating station had been built by the Midland during March 1893 in Calvert Street, Derby to provide current to light the station offices, the Midland Hotel and the Locomotive Works offices.
A textile research facility was opened in Calvert Street for upholstery and seat materials.
This facility is thought to have used the buildings made redundant by the closure of the 1893 generating station when the new generating station was brought on line in 1910.
Johnson retired in 1903 and was succeeded by Richard Mountford Deeley who began as an apprentice at the works. He carried on much where Johnson had left off, but improved the compounds with an uprated boiler and firebox, also changing the tender to a smaller six-wheeled design. Deeley was very soon promoted to Locomotive Superintendent, with Cecil Paget as Works Manager.
In 1904 two steam motor-carriages for the Morecambe-Heysham service were fitted out at the carriage works. Since he was also Locomotive Superintendent, he reorganised the numbering system in 1907 so that different groups of numbers were used for different classes. Among his improvements to the works, he devised a heavy testing rig for structure testing up to 50 tons in what had developed into a dedicated Engineering Testing Department.
By 1900 some 40,000 people were employed, producing 40 new engines a year. Electric power and lighting was installed in the Locomotive Works during 1910, supplied by the company's new generating plant located across the Derby canal at the rear of the Works. An earlier and smaller scale electric generating station had been built by the Midland during March 1893 in Calvert Street, Derby to provide current to light the station offices, the Midland Hotel and the Locomotive Works offices. A textile research facility was opened in Calvert Street for upholstery and seat materials. This facility is thought to have used the buildings made redundant by the closure of the 1893 generating station when the new generating station was brought on line in 1910.
Derby Works