John Rennie was one of the distinguished group of Scottish engineers whose work contributed so much to the industrial and commercial development of the United Kingdom in the early 19th century. With the exception of roads, in which he appears not to have been interested, and steam engines, which he promised Watt not to build - though he frequently constructed the accompanying machinery - there was very little in the field of engineering that lay outside the range of his activities. This exceptional diversity is reflected in this collection of his papers, which covers his entire working life from his first visit to England in 1784 to his death. The papers are from his own office, and consist principally of incoming letters from clients, site engineers, contractors, suppliers, and tradesmen, draft reports and estimates, letterbooks, and notebooks. The collection is especially rich for the last fifteen years of his life, and for his major works, though the notebooks give a clear and consistent view of his activities throughout the 1790s. Apart from the projects with which Rennie alone was involved, he frequently collaborated with, or was consulted by colleagues, and his papers are thus an important source of information about Robert Stevenson, Thomas Telford, the Watts, the Boultons, the Jessops, and many other engineering contemporaries.