| MLR No.1-4 | |
| Powertype: | Steam |
| Builder: | Orenstein & Koppel |
| Serialnumber: | 1766, 2342, 2343, 1777[1] |
| Builddate: | 1905[2] |
| Totalproduction: | 4 |
| Driverdiameter: | 303NaN3 |
| Locoweight: | 15 tons (empty), 17 tons (working) |
| Watercap: | 450impgal |
| Firearea: | 72NaN2 |
| Boilerpressure: | 176 psi |
| Totalsurface: | 452square feet[3] |
| Cylindercount: | 2 |
| Cylindersize: | 11.81x |
| Tractiveeffort: | 811012NaN2 at 85% boiler pressure [4] |
| Operator: | Matheran Hill Railway |
| Fleetnumbers: | MLR 1-4 (old) MLR 738-741 (new) |
| Firstrundate: | 1907 |
| Retiredate: | 1982 |
| Disposition: | All four preserved |
The MLR nos.1-4 were a series of four steam locomotives that ran the Matheran Hill Railway, and were supplied by the German engineering company Orenstein and Koppel.[5] These served on the railway from its inauguration in 1907, until 1982, when they were withdrawn from service, and completely replaced by diesel locomotives.[6]
To navigate the tight curves on the MLR, the locomotives were fitted with an articulated wheel design, based on a patent by one John Clark in 1870.[7] The design allowed for the rods to remain parallel to the engine at all times, while the wheels would follow the track's curves.[8] The driving axles were Klien-Lindners.
The locomotives served on the line exclusively until 1965, when diesel traction was introduced on the line. Eventually, the four engines were retired in 1982,[9] with all of them have been preserved at various locations.
Out of the four Locomotives, only three remain in India, while the fourth has been transported to the UK in 1986, where it passed through multiple owners.
No.738 is plinthed at a mini-garden near the premises of the Neral Toy Train station. No. 739 is situated at National Rail Museum, New Delhi, while No. 741 is plinthed within the yard premises of Matheran Railway Station. No.740 was the locomotive ferried to UK, and was acquired by Amberley Chalk Pits Museum. It was then fully restored, and put to working condition. Between 2003 and 2008, it was on service on Leighton Buzzard Railway.[6]