This series includes papers concerning the involvement of BTH in jet engine design and construction, and especially its collaboration with Frank Whittle and his company Power Jets Ltd. in the construction and testing of the earliest British jet engines. For an account of the conents of these papers, see Michael Hughes, 'British Thomson-Houston and Whittle Gas Turbine and Jet Engine Records in the Marconi Archives', Bodleian Library Record XX (2007), 153-8.