The young woman in this photo is posing with a balloon. It is likely filled with hydrogen instead of helium because helium had not been isolated until the mid 1890s. However it could be helium, depending on when the photo was taken; in which case this would be a photograph of one of the first helium balloons.
It is interesting that the balloon is a perfect sphere instead of the pear shape common with today’s balloons. This is probably because the rubber used at the time was much thicker and more rigid than today’s balloons.
The girl in the picture does not look that happy, despite having such a novelty in her hands. However her lack of smile is probably due to the way pictures were taken back then. Because of long exposure times people had to hold very still so as not to cause blurring. And since it is hard to hold a smile for any length of time, people tended not to smile in these old photographs.