In the 18th and 19th centuries, banknotes were handwritten or part-printed and could be exchanged, in whole or in part, for an equivalent amount of gold when presented at the bank. During the First World War the British Government wanted to maintain its stocks of bullion and so banks were ordered to stop exchanging banknotes for gold. One poundand 10 shilling notes were introduced by the Treasury in lieu of gold sovereigns. These notes were nicknamed "Bradburys" because of the prominent signature of Sir John Bradbury, Permanent Secretary to the Treasury displayed on the notes. Britain returned to the gold standard in 1925, but the Bank of England was only obliged to exchange notes for gold in multiples of 400 ounces or more. The responsibility for the printing of ten-shilling notes was transferred to the Bank of England in 1928, and the right to redeem banknotes for gold ceased in 1931 when Britain stopped using the gold standard. The first Bank of England ten-shilling notes were two-sided, red, printed banknotes featuring the declaration "I promise to pay the bearer on demandthe sum of ten shillings" on the front. This declaration remains on Bank of England banknotes to this day. In 1940, during the Second World War, ten-shilling notes were issued in a new mauve and grey colour scheme in order to deter counterfeiters, although the design remained the same. At the same time, a metallic thread running through the paper was introduced as a security feature. After the war ten-shilling notes were issued in their original red colour. The earliest post-World War II notes did not have the metallic thread security feature, but those issued from October 1948 onward did. A new design for 10/- notes was introduced in 1961, with the old notes ceasing to be legal tender in 1962. These new series C notes were slightly longer and narrower, and were the first 10/- notes with a portrait of Queen Elizabeth II on the front. The reverse design incorporated the logo of the Bank of England. In the late 1960s it was decided that future banknotes should feature a British historical figure on the reverse. The first such note was the series D £20 note, first issued in 1970, featuring William Shakespeare. A design for a 10/- note featuring Walter Raleigh on the reverse was approved in 1964, but this was never issued. Instead, in 1969, as part of the process of decimalisation, a new fifty pence coin was introduced as a replacement for the 10/- note. The principal reason for the change was economy: the notes had an average lifetime of about five months whereas coins could last at least fifty years. The series C 10/- notes ceased to be legal tender on 22 November 1970. In the Isle of Man, both the English and Manx 10/- notes continued to be legal tender for 50 pence until 2013.
