Silk mill
A silk mill is a factory that makes silk for garments using a process called silk throwing. Traditionally, silk mills were concentrated in Japan, England, New Jersey, Pennsylvania and Switzerland. The silk throwing process. Silk is a naturally produced fibre obtained from many species of the silk moth. In 1700 the favoured silk was produced by a moth (Bombyx mori), that spun a cocoon to protect the larvae. The larvae fed on mulberry leaves grown in Italy. Silk fibres from the Bombyx mori silkworm have a triangular cross section with rounded corners, 5–10 μm wide. The silk is  a protein, fibroin, that was cemented in place by the use of gum, another protein, sericin. The cocoons were harvested and placed in troughs of hot water to dissolve the gum and allowed the single thread to be wound into a skein. The skeins were placed into bales and taken to the mill for processing. Three sorts of yarn could be produced: "no-twist" which was suitable for weft, "tram" that had received a slight twist making it easier to handle, and "organzine" which had a greater twist and was suitable for use as warp." "Reeling" is the industrial process  where silk that has been wound into skeins, is cleaned, receives a twist and is wound onto bobbins. "Silk throwing" is the process where the thread from the bobbins is twisted again to form "tram" and or "organzine". The yarn is twisted together into threads, in a process known as "doubling". Colloquially silk throwing can be used to refer to the whole process: reeling, throwing and doubling. History. The Itailans were the first to build mills that contained anything more than a set of spinning wheels. Thomas Cotchett's mill, was built in Derby in 1704, and was a failure . John Lombe had visited the successful silk throwing mill in Piedmont in 1716, an early example of industrial espionage. He returned to Derby with the necessary knowledge, with details of the Italian silk throwing machines – the and the – and some Italian craftsmen. He designed the mill, and with his half-brother Thomas Lombe (born 1685) instructed George Sorocold to build it and fit it with the new machines. Lombe's Mill was the first successful silk throwing mill in England and probably the first fully mechanised factory in the world. Between 1717 and 1721 George built the mill, beside the  River Derwent to the south of Cotchett's failed Mill to house machines for "doubling" or twisting silk into thread. The machines required large buildings and a power source. An undershot water wheel turned by the mill fleam served the purpose. John Lombe was given a 14-year patent to protect the design of the throwing machines. The King of Sardinia reacted badly to the commercial challenge, placing an embargo on the export of raw silk. John's elder brother, Sir Thomas Lombe, took over the business. When the patents lapsed in 1732, other mills were built in Stockport and  Macclesfield. The throwing machines were two storeys high and pierced the first floor. The winding machines were situated on the top three floors. All the machines were powered by Sorocold's seven-metre diameter, two-metre wide external undershot waterwheel. That drove a line shaft that ran the length of the mill. The and took their power from the shaft. The mill was heated to process the silk, and this was explained in the 1718 patent: It was reported that Lombe used a fire engine (steam engine) to pump hot air round the mill . The circular spinning machines (also known  as 'throwing machines'), were the most significant innovation of the factory. Together with the single source of power (water), and the large size and organisation of the workforce for the period (200-400, according to contemporary sources), the total process of production from raw silk to fine quality thread has led the Lombes' silk mill to be described as the first successful use of the factory system in Britain. United States. The history of industrial silk in the United States is largely tied to several smaller urban centres in the Northeast region. Beginning in the 1830s, Manchester, Connecticut emerged as  the early centre of the silk industry, when the Cheney Brothers became the first to raise silkworms on an industrial scale. With the mulberry tree craze of that decade, other smaller producers began raising silkworms: this economy gained traction around Northampton, Massachusetts and Williamsburg, where a number of small firms and cooperatives emerged. William Skinner, relocated from there to the then-new city of Holyoke after the 1874 flood. Over the next 50 years he and his sons would maintain relations between the American silk industry and its counterparts in Japan, and by 1911, the Skinner Mill complex contained the  world's largest silk mill under one roof: Skinner Fabrics had become the largest manufacturer of silk satins internationally. Other efforts later in the 19th century would also bring the new silk industry to Paterson, New Jersey, with several firms hiring European-born textile workers and granting it the nickname "Silk City". World War II interrupted the Asian silk trade, and silk prices increased dramatically. U.S. industry began to look for substitutes, which led to the use of synthetics such as nylon. Synthetic silks have also been made from lyocell, a type of cellulose fibre, and are often difficult to  distinguish from real silk (see spider silk for more on synthetic silks). Industrial unrest. In New Jersey, disputes between silk mill workers and owners lead to the 1913 Paterson silk strike and the 1926 Passaic Textile Strike