The photographs are on an auto scroll slide show so they will automatically change to the next one every few seconds.

They can also be operated manually by clicking the mouse pointer on either of the chevrons on the left or right hand side of the photograph.

By clicking the mouse pointer on the photograph, it will be shown as a still photograph in  expanded mode. You can move through the photographs in expanded mode by clicking on either of the chevrons or return to the auto scroll slide by clicking on the "X" in the top right hand corner of the expanded photograph