The steam locomotive narrow gauge measures between 578 mm and 1000mm. If you've ever pictured a steam engine train chugging away in the backdrop of craggy mountains, you've got it right. The narrow gauge is a type of steam locomotive gauge that is used for mountainous terrain and mining operations. Steam locomotives for such terrain are miniature in design to reduce operating weight. In the United States, the White Pass and the Yukon Route are narrow gauge steam locomotive gauges, while the Darjeeling Toy Train in India is a steam train that runs on a narrow gauge.
The standard gauge steam locomotive gauge measures 1,435 mm, or 4 feet 8.5 inches. The history behind this type of steam locomotive engine is special, since the gauge was designed before steam trains had even hit the ground. Based on the width of coal wagons, the standard gauge is today the most commonly used gauge in the world, be it for steam locomotives or diesel engines. Some of the steam locomotives that used the standard gauge include the LMS Royal Scot Class 6100, the SY (2-8-2), JS (2-8-2), and QJ (2-10-2) locomotives.
The broad gauge is considered to be any gauge that measures on the upper end of 4 feet 8.5 inches, which happens to be the measure for the standard gauge. Of steam locomotive gauge types, the broad gauge is somewhat of an enigma, with many different gauge measures falling into this range. The Russian gauge, Indian gauge, Irish gauge and Iberian gauge are all broad gauge steam locomotive gauges that became popular over the years because of their higher operational weight, better facility and faster speed.
In the 19th century, steam locomotives were the main transporters of industrial products and mined materials. Since terrain was rough, the steam locomotive gauge gradually increased from the narrow gauge to the standard to the wide, although the narrow gauge still remains a favorite for hilly terrain. This is seen by the steam locomotives chugging across the picturesque landscape of Wales or the Darjeeling Toy Train puffing its way to the queen of hill-stations in India: Darjeeling.
