Calthrop worked as a locomotive inspector for the Great Indian Peninsula Railway, and in 1886 requested leave to investigate proposals for independent branch lines. He identified two schemes of particular interest – a tramway connecting the Hindu religious centre of Nasik with the railway, and a branch line to the town of Barshi. The Great Indian Peninsula Railway approved both schemes, and Calthrop undertook a survey of both lines. In 1887 he registered the Indian Railways Feeder Lines Company in London to promote the construction of feeders to the railway, and began negotiations with the Indian government to build the Barsi Light Railway. The GIPR suggested that he either return to his duties as a locomotive inspector, or resign to further promote branch lines. His health was failing, and in 1889 Calthrop resigned from the GIPR. Working as a consultant, he then supervised construction of the gauge horse-powered Nasik Tramway using his previous survey. In 1895 the negotiations that began in 1887 were finally successful and Calthrop formed a new company to build the Barsi Light Railway, employing himself as consulting engineer. Calthrop surmised that the axle load on the axles of all rolling stock could be equal, allowing maximum loading of goods wagons. He settled on a load of per axle, which was light enough to allow railway lines to be built with rail. Further, he argued that using a track gauge of was the best compromise between economy of construction and carrying capacity. Five 0-8-4T locomotives were constructed to Calthrop's specification by Kitson and Company. The goods rolling stock was constructed on common pressed-steel underframes, reducing tare weight and maximising wagon loads. Calthrop recognised the importance of railways in warfare, and designed the rolling stock to facilitate the movement of troops and equipment. Rolling stock rode on pressed-steel Fox bogies, using the Timmis system of double coiled springs. The line was constructed with rail inclination, which involves tilting the rail a few degrees to make its surface more nearly parallel with that of the rim of the wheels. Inclination is now applied universally to railways. Prior to shipment of the rolling stock to India, Calthrop and the Leeds Forge Company, manufacturer of the rolling stock, conducted tests on a specially built test track located at Newlay, near Leeds. The line was opened for inspection by railway officials and journalists, and a number of reports were published in the technical railway press. The BLR finally opened in 1897, and was extended on a number of occasions until it reached a total length of in 1927. It is regarded as having revolutionised the narrow-gauge railway system on the Indian subcontinent; the railway was immensely successful, establishing Calthrop as one of the leading figures in the field. Calthrop remained Consulting Engineer until he retired, due to ill health, two years before his death. The BLR continued to be operated as a privately owned railway until 1954, when it was purchased by the Indian Railways.
Purchased by the Indian Railways
In 1954, it was discussed in Parliament, to wit:
"That, the Bill to impose upon the Barsi Light Railway Company, Limited, an obligation to make certain payments to the Central Government, be taken into consideration." The Barsi Light Railway Company was the last of the Sterling Companies operating in India and Government decided in December 1952 to exercise the option under the contract to purchase the Railway by giving a year's notice. Accordingly, after the expiration of the notice period the Railway was taken over on the 1st January, 1954 and is now a part of the Central Railway System. The Company expressed its willingness in November 1953 to accept the liability but pleaded that it was legally incompetent to do so under the English Law applying to the Company which was incorporated in the United Kingdom. According to that Law, the Company was incompetent to make any gratuitous payments from out of the purchase price.
Influences
Internationally, other narrow-gauge railways copied the Calthrop ideas, such as the Victorian narrow-gauge railways in Australia, which was persuaded to change from gauge to gauge so as to use the rolling stock designs already available for this gauge. The four lines in Victoria totalled 190.7 miles in length.
Conversion to broad gauge
The Kurduwadi–Miraj section was converted to broad gauge in 2002. The Latur–Osmanabad section was converted to broad gauge in September 2007.. Finally the remaining Osmanabad–Kurduwadi section of broad-gauge track became operational in October 2008.
