Claims that the Bank of England began to act as a Lender of Last Resort as early as the mid-eighteenth century date back to Adam Smith and Henry Thornton. This article presents evidence on the Bank's financial market interventions during the 1763 and 1772-1773 crises, and concludes that although the former was too gradual to be truly representative of last resort lending by 1772 the means of intervention described by Thornton were largely in place. Although direct evidence for the Bank's decision making process on either occasion is lacking, the universal contemporary conviction of its unique resources and obligations make it unlikely that it was entirely motivated by political considerations or cronyism. Its actions are instead consistent with Thornton's crisis containment narrative of banknote loans to London bankers, which in turn was the optimal response for containing financial contagion by ensuring the continued health of the bills of exchange network.