The Marriott C17 (M&GN Class A) Atlantic Tank Engines
The Class A locomotives were designed at the Midland & Great Northern Joint Railway (M&GN) Melton Constable Works by the Chief Draughtsman G.B. Clarke under the direction of the M&GN's Locomotive Engineer Marriott. Officially the Melton Constable Works did not build new locomotives, so these engines were described as rebuilds of 4-4-0s, although no 4-4-0s were withdrawn to donate parts.
The design may have been a development of the Beyer, Peacock outside-cylinder 4-4-0s already in use on the M&GN, but it may have also been based on the Tilbury 4-4-2Ts. The boiler was virtually identical to the S.W. Johnson design used on various M&GN 4-4-0s and 0-6-0s of Midland design. However they differed in that they had closed domes, and the Ramsbottom safety valves were over the firebox. As would be expected from the Joint Railway's ownership, many of the fittings were of mixed design. Most were of Midland appearance, but the trailing radial truck followed Doncaster (Great Northern) practice.
Only three locomotives were built. No. 41 was built in 1904, No. 20 in 1909, and No. 9 in 1910. They were used between Lowestoft and Yarmouth Beach shed, as well as the Potter Heigham local service, and the Cromer Beach to Melton Constable trains.
The tanks originally had a square profile, but Nash fitted sloping fronts between 1933 and 1934 to improve the view from the cab. Nash had moved from Swindon in 1928 to succeed Marriott. The Swindon influence is clearly visible in the resulting tank profile. The modification resulted in a reduction of water capacity from 1650 gallons to 1600 gallons, and a reduction in weight of 10cwt.
The Class A locomotives entered LNER ownership with the rest of the M&GN stock on 1st October 1936. By this point, all three were allocated to Melton Constable, and continued to be described as "Class A" until July 1942 when they were given the designation of Class C17.
Between 1938 and 1939, No. 020 was transferred back to Yarmouth Beach, but would return to Melton Constable. All three engines then stayed at Melton Constable until withdrawal. No. 020 was withdrawn in April 1942, No. 041 in January 1944, and No. 09 in July 1944.
Technical Details
| Cylinders (x2): | (outside) | 17.25x26in. |
| Motion: | Stephenson (slide valves) | |
| Boiler: | Max. Diameter: | 4ft 3in |
| Pressure: | 160psi | |
| Diagram No.: | 46A | |
| Heating Surface: | Total: | 1078 sq.ft. |
| Firebox: | 110 sq.ft. | |
| Tubes: | 968 sq.ft. (194x 1.75in) | |
| Grate Area: | 17.5 sq.ft. | |
| Wheels: | Leading: | 3ft |
| Coupled: | 6ft | |
| Trailing: | 3ft 7in | |
| Tractive Effort: | (@ 85%) | 13,491lb |
| Total Wheelbase: | 29ft 6in | |
| Engine Weight: | (full) | 68 tons 9cwt |
| Max. Axle Load: | 17 tons 18cwt | |
| Coal Capacity: | 2 tons 0cwt | |
| Water Capacity: | 1900 gallons |
Preservation
None of the C17 Atlantics survived into preservation.
Models
Ace Models sell a 7mm scale (O gauge) kit of the C17.