Click the "thumbnail" to be downloaded. In the upper right corner of the screen, click the right-most icon. Click the fourth icon down (looks like a cloud with an arrow in it) and a dialog will quide you to save the file to your computer.
Selecting the Facebook icon will allow you to upload the photo to your Facebook page.
If the photo is "geo-tagged" the location may be viewed on Google Maps. Follow the guidelines above to locate the "Map" link (a small folded map). Clicking the link will open up a new window showing where the photograph was taken. You may need to zoom the map to get additional detail. Simply close the new window to return to browsing the gallery.