Highland Railway Loch or B class
Highland Railway 125 Loch Tay
Type and origin Power type Steam Designer David Jones Builder Dübs & Co. (15) North British Locomotive (3) Serial number Dübs:3392–3406 NBL: 21456–21458 Build date 1896 (15), 1917 (3) Total produced 18
Specifications Configuration: ​  • Whyte 4-4-0  • UIC 2′B n2 Gauge 4 ft 8+1⁄2 in (1,435 mm) Leading dia. 3 ft 3 in (0.991 m) Driver dia. 6 ft 3+1⁄2 in (1.918 m) Loco weight 54 long tons 10 cwt (122,100 lb or 55.4 t) Water cap. 3,000 imp gal (14,000 L; 3,600 US gal) Boiler 4 ft 4+7⁄8 in (1.34 m) diameter Boiler pressure 175 lbf/in2 (1.21 MPa) Heating surface 1,295 sq ft (120.3 m2) Cylinders Two, outside Cylinder size 19 in × 24 in (483 mm × 610 mm) Valve gear Allan Valve type New: piston valves Rebuilt: Balanced slide valves
Performance figures Tractive effort 17,070 lbf (75.93 kN)
Career Operators Highland Railway → LMS → BR Class HR: Loch; B (from 1901) Power class LMS: 2P Withdrawn 1930–1950 Disposition All scrapped

The Highland Railway Loch class locomotives were large 4-4-0s normally used north of Inverness. They were introduced in 1896, to the design of David Jones. Fifteen were built by Dübs and Company in Glasgow, all going into traffic between July and September 1896. Three more were built in 1917 by Dübs' successor, the North British Locomotive Company (NBL).

Design

They had the typical Jones appearance with outside cylinders, domed cab roof, louvred chimney, but, as with the Jones Goods class 4-6-0, the Allan style front framing was dispensed with. Allan valve gear was still used.

Numbering

Built by Dübs in 1896

Built by NBL in 1917

These were needed primarily for the increased traffic on the Kyle line where they were the heaviest locomotives permitted. This period was when the initial traffic of the United States effort in World War I was flowing, and much was brought to the west coast of Scotland in an effort to reduce the effect of the U-boat menace. The trains ran from Kyle to Invergordon so it was a wholly HR traffic.

Transfer to LMS

They passed to the London, Midland and Scottish Railway (LMS) in 1923. The LMS classified them '2P'. Withdrawal occurred from 1930 onwards.

Transfer to BR

Only two survived into British Railways (BR) ownership in 1948. Neither received their allocated BR number before being withdrawn in 1948 ('Loch Insh') and 1950 ('Loch Tay').

References

• Baxter, Bertram (1984). Baxter, David (ed.). British Locomotive Catalogue 1825–1923, Volume 4: Scottish and remaining English Companies in the LMS Group. Ashbourne, Derbyshire: Moorland Publishing Company. pp. 194–195.
• Casserley, H. C. & Johnston, Stuart W. (1974) [1966]. Locomotives at the Grouping 3: London, Midland and Scottish Railway. Shepperton, Surrey: Ian Allan. p. 141. ISBN 0-7110-0554-0.