An eighteenth-century water cistern from the previous house on the site of No. 12 Lincoln's Inn Fields, retained by Soane and with the owner's initials, EP for Edmund Proudfoot who purchased 12 Lincoln's Inn Fields 19 August 1763 and lived there until 4 May 1767.

The fixtures list in the earliest surviving lease for No. 12 post-Soane dates from 1847, to E.T. Whitaker (Soane Archive), includes a 'lead cistern' in the Back Kitchen in the basement. In 1900 new tenants Currie William and Williams were given permission to carry out alterations. Soare Archives: Curatorial papers: Birch. Specification of Works proposed to be executed to ...No. 12 Lincoln's Inn Fields. To be completed by May 31 1901
includes work to create a new basement Strong Room including to Clear away dwarf walls supporting lead cistern and carefully transport and deposit Cistern in yard at back in position selected by Curator. This is clearly this lead cistern, which was recorded in the No. 12 courtyard by Walter Spiers in his 1906 inventory.

Such cisterns followed a common pattern and were used to store cold water for drinking or other kitchen use. A number of others survived in Lincoln's Inn Fields into the twentieth century. The 1912 Survey of London volume on St. Giles-in-the-Fields recorded two cisterns at 15 Lincoln's Inn Fields (dated 1742 with the intials W.C. and 1752 with the initials F.T.) and another at 45 Lincoln's Inn Fields (dated 1752 with the initials A.A.). A note by John Summerson slipped into the Museum's copy of the Survey volume records another at No. 24, dated 1787 and with the initials M.P. for the then owner Meredith Price.