This book tells for the first time the definitive history of this innovative 15-inch-gauge railway on the Blakesley estate in rural Northamptonshire and the Victorian transport engineering family that created it. The Bartholomew family, although almost unknown today, represented a waterway and railway engineering dynasty in Yorkshire for many decades. Prior to the railways, two Bartholomew brothers were in engineering control of virtually the entire waterway network of the West Riding. Blakesley's Squire, Charles William Bartholomew, created a miniature estate railway based deliberately not on British ideas but on state-of-the-art equipment from America and Germany, which was to act as a model for such lines in Britain for the next century. For the first time, this book attempts to outline the evolution of the American 'Cagney' miniature railway products, which he adopted, in comparison with the 'minimum gauge' ideas of Sir Arthur Heywood. The Squire was also one of the very first - in 1905 - to produce in-house a petrol locomotive, and followed this by commissioning the world's first steam-outline version - a locomotive able in 2009 to celebrate, in working order, its centenary as the world's oldest surviving internal combustion locomotive. The line survived the Squire's death in 1919, and functioned in a declining role into the 1930s, when much of it went to create a similar line in Sussex, a role newly revealed by the author's researches for this book. The family also became embroiled in one of the biggest fraud scandals and court cases of the Second World War, involving a middle-aged spinster family friend. The line's remaining equipment was also acquired by this lady, before being repossessed by the family and sold on for a somewhat nomadic existence around the North East. Amazingly, one complete locomotive, parts of another, and a carriage bogie have survived into preservation, the first and last being in the author's care.