21. The "'1962 Tube Stock "'was a type of London Underground tube train built for use on the Central line. 22. The 1972 Stock was ordered to make up the shortfall in trains on the Northern line's 1959 Tube Stock fleet. 23. In the early 1960s, the extension of electrification of the Metropolitan line to saw the introduction of four-car 1972 tube stock . 24. The "'1949 Tube Stock "'was composed of ninety-one cars built by the Birmingham Railway Carriage and Wagon Company in Smethwick, England. 25. The "'Watford Joint Tube Stock "'was built for the service to Watford along both the Underground and the London North Western Railway. 26. With the introduction of the 1995 Tube Stock in 1999 . The 1972 Mark 2 stock was extensively refurbished in the 1990s. 27. Originally it was planned to refurbish some 30 1938 trains, but this was scrapped in favour of 30 new trains-1972 Mk1 Tube stock . 28. These led to the 1996 tube stock ; refurbishment of the 1983 stock was being considered, but building new trains cost about the same. 29. Upon entering service in April 1993, the new units gradually replaced the previous 1962 tube stock , which was finally withdrawn two years later. 30. The design managed to be both stylish in an appropriately Warholesque way and self-evidently simple to manufacture from the raw sheet and tube stock .
