Dear Brendan,

E. Liebenberg published two sheet index of this map in her paper : 

Liebenberg, Elri, "The « Major Jackson’s Transvaal and Natal Series » of the Anglo-Boers War (1899-1902) : A Cartobibliographic Framework", in Elri Liebenberg, Peter Collier et Zsolt Gyozo Török (éd.), History of Cartograpy, International Symposium of the ICA, 2012, Heidelberg, Springer, 2014, p. 211-232.

Photos are arriving through wetranfer