of the factory system that also featured the division of labor. Mills One of the earliest factories was John Lombe's water-powered silk mill at Derby, operational by 1721. By 1746, an integrated brass mill was working at Warmley near Bristol. Raw material went in at one end, was smelted into brass and was turned into pans, pins, wire, and other goods. Housing was provided for workers on site. Josiah Wedgwood in Staffordshire and Matthew Boulton at his Soho Manufactory were other prominent early industrialists, who employed the factory system. Cotton spinning The factory system began widespread use somewhat later when cotton spinning was mechanized. The first use of an integrated system, where cotton came in and was spun, bleached dyed and woven into finished cloth, was at mills in Waltham and Lowell, Massachusetts. These became known as Lowell Mills and the Waltham-Lowell system. The Nasmyth, Gaskell and Company's Bridgewater Foundry, which began operation in 1836, was one of the earliest factories to use modern materials handling such as cranes and rail tracks through the buildings for handling heavy items. Arkwright Richard Arkwright is the person credited with being the brains behind the growth of factories and the Derwent Valley Mills. After he patented his water frame in 1769, he established Cromford Mill, in Derbyshire, England. The factory system was a new way of organizing labour made necessary by the development of machines which were too large to house in a worker's cottage. Working hours were as long as they had been for the farmer, that is, from dawn to dusk, six days per week. Machine tools and interchangeable parts An early instance of transition from skilled craftsmen to machine tools began in the late eighteenth century. In 1774, John Wilkinson invented a method for boring cannon barrels that were straight and true every time. He adapted this method to bore piston cylinders in the steam engines of James Watt. This boring machine has been called the first machine tool. Mass production using interchangeable parts was first achieved in 1803 by Marc Isambard Brunel in cooperation with Henry Maudslay, and Simon Goodrich, under the management of (with contributions by) Brigadier-General Sir Samuel Bentham, the Inspector General of Naval Works at Portsmouth Block Mills at Portsmouth Dockyard, for the British Royal Navy during the Napoleonic War. By 1808 annual production had reached 130,000 sailing blocks. This method of working did not catch