Within each gallery, the images are linked together. In order to traverse through them, simply move your mouse over the left or right side of the image. The half that you moved your mouse over will display a tab, labeled "right" or "left". If you click on the tab, either the previous or the next image will be loaded. If you are already at the beginning or the end of the list, the tab for the previous or the next (respectfully) will not be displayed.