There are lots of tools and navigation items that can be used in these galleries which are described below.
After clicking on your chosen gallery you can scroll through the thumbnails until you reach the footer menu. This can be done either using the mouse wheel or the scroll bar on the right. On phones and tablets simply drag.
Click on any thumbnail to reveal a large photo where you can run a slideshow or navigate backwards and forwards using the side arrows, mouse wheel, arrow buttons on your keyboard or simply dragging the photo sideways which can also be done on a smart phone or tablet.