Fowler was born in
Evesham, Worcestershire, on 29 July 1870. His father, also named Henry, was a
furniture dealer, and his family were
Quakers. He was educated at Prince Henry's Grammar School, Evesham (now
Prince Henry's High School, Evesham), and at
Mason Science College (which became the
University of Birmingham) between 1885 and 1887 where he studied
metallurgy. He served an
apprenticeship under
John Aspinall at the
Lancashire and Yorkshire Railway (L&YR)'s
Horwich Works from 1887 to 1891. Fowler was elected as a
Whitworth Exhibitioner in 1891. He then spent four years in the Testing Department under
George Hughes, whom he succeeded as head of the department. He married Emmie Needham Smith in 1895, and they had three children. Emmie died in 1934. In 1909, he succeeded
Richard Deeley as
chief mechanical engineer (CME) of the MR. Between 1915 and 1919, Fowler was employed on
war work and
James Anderson became acting CME. During the First World War he was seconded to the Ministry of Munitions, being director of production from 1915 to 1917 and then assistant director general of aircraft production. In 1919, Fowler was made a Knight Commander of the Order of the British Empire (KBE) for his contributions to the war effort. On the
Grouping of 1923, he was appointed deputy CME of the newly formed
London, Midland and Scottish Railway (LMS), under George Hughes and became CME in October 1925. He was also invited to serve on the Government
Bridge Stress Committee investigating stresses in railway-bridges, especially as regards the effects of moving loads Along with Anderson, Fowler was responsible for the adoption by the LMS of the Midland's small engine policy. Various Midland standard types were built by the LMS, including the 4P Midland
Compound 4-4-0, the 2P 4-4-0, the 4F 0-6-0, and the 3F 0-6-0T. The small engine policy resulted in frequent
double-heading, as the locomotives were not powerful enough to cope with loads, and thus increased expense. Standardisation also left these standard locomotives with short-travel
valves and small axle boxes, the former leading to inefficiency and the latter to frequent hot axle boxes. In 1928, the LMS introduced the
Royal Scot 4-6-0 express passenger locomotive, based on the
SR Lord Nelson Class. In another departure from the small engine policy, several
2-6-0+0-6-2 Beyer-Garratts were acquired for the
Toton-
Brent coal trains. However, interference from Derby meant that the locomotives received standard small axle-boxes and short-travel valves, with the result that they were poor performers. Fowler was not a hands-on engineer in the mould of
George Jackson Churchward. Although (as was traditional) designs produced during his tenure were credited to him as "Fowler" locomotives, the majority of the work was done by his staff, with minimal personal involvement from Fowler. An analogy may be made with his successor Sir William Stanier's Princess Coronation (Duchess) class, which was largely designed by LMS draughtsmen while Stanier was out of the country, although Stanier was more deeply involved in other designs during his tenure. In 1930, Fowler became President of the
Whitworth Society as successor to Mr. F. H. Livens, J.P. Fowler retired in 1933,
Ernest Lemon initially taking over as CME for a short period before
William Stanier was head-hunted into the job from the
Great Western Railway. Stanier was to reform LMS locomotive policy. Fowler died on 16 October 1938 at his home,
Spondon Hall (now demolished), Derby. He was buried in the
Nottingham Road Cemetery, Chaddesden, Derby. == Locomotive designs ==