 Complete the following phrase:  Appointed Master of Fire Engines at the age of 24, two months prior to the Great Fire of Edinburgh, Braidwood established principles of fire-fighting that are still applied today. His training as a surveyor gave him exceptional knowledge of the behaviour of building materials and housing conditions in the Old Town of Edinburgh. He recruited to the service expert tradesmen  slaters, carpenters, masons and plumbers  who could apply their various fields of expertise to fire fighting. He also recruited experienced mariners for an occupation that required heavy manual work in hauling engines and trundling wheeled escape ladders up and down Edinburghs steep streets, as well as nimble footwork when negotiating rooftops and moving through partially destroyed buildings. His many original ideas of practical organisation and methodology, published in 1830, were adopted throughout Britain. He was, however, resistant to the introduction of steam-driven engines. In 1833 he left Edinburgh to lead the London Fire Engine Establishment. The London Fire Engine Establishment had to fight a blaze at the 