Thank you for identifying Elsberger. Here is another of him and Grothaus as well.
Officers of the German Corps under General Louis Botha
Second Row: Dr. W. Vaheutin Lieut. Von Quitzow Lieut. Grothaus (Transvaal Artillery)
Front Row: Prince von Jutrzenka Lieut. Von Zelewski Dr. Elsberger (standing)
The man leaning against the tree is not identified. Note black puppy at bottom right.
From: With the Flag to Pretoria, H. W. Wilson Vol 1 1900 and britishbattles.com