The contents are as follows. (i) Letters of and to J K Rennie, 1857-1896 (folio 1). (ii) Correspondence of George Banks Rennie concerning the Smeatonian Society, 1901-1902, 1908 (folio 179); (iii) Correspondence of William Rennie, barrister, and other family letters, 1893, 1907-1928 (folio 310); (iv) Letters of Lord Allenby to John Rennie Maudslay, 1921, 1936, undated (folio 405).