It shows a working-class man sitting on his horse.
The picture is one of a series - the man's job appears to be collecting something, presumably shellfish or crabs, or possibly even birds' eggs from a pebbly beach.
The man is wearing a cap.
The horse is wearing blinkers, a saddle, and a pair or rather uncomfortable-looking wooden crates, presumably to carry whatever it is the men collect from the beach.
I think the picture was taken in France.
This is a SMALL photograph - 3 1/2" x 2 1/2" approx (9 cm x 6 cm).