This photo is great as it is an enlargement (Many thanks to Major [Retd] Janet Brodie-Murphy) of the previous black & white and colour ones and shows much more detail of the croquet players.

The nurse looks like she is doing her part and I imagine that all the others are patients at the Sanatorium, the one on the left looks like an umpire. The uniform the nurses had to wear there I would think would be very hot on what appears to be a warm day.

Croquet is a sport that involves hitting wooden or plastic balls with a mallet through hoops embedded in a grass playing court.

 

 ©peh