Investigating the Great Drain ... 31-E-48 (Nomlas.) Horizontal (normal) ... 22 July 1931
View of the Great Drain ... north Horizontal (normal) ... 21 March 1934
Wall of the Great Drain ... Horizontal (normal) ... 21 March 1934
Wall of the Great Drain ... east Horizontal (normal) ... 21 March 1934
Trench to the west of the Great Drain ... Horizontal (normal) ... 5 May 1934
View of the Great Drain and the related channels ... Horizontal (normal) ... 12 May 1934