PDF's on Mobile Devices
1. Tap on the three vertical dots on top right of display then select "Desktop site" from drop-down menu.
2. Wait a moment or two for the files to repopulate then pinch the first one with your thumb and index finger to enlarge and center. Now you are able to scroll.
3. When through viewing, tap on the three vertical dots again. (If they're out of view, drag your screen down a wee bit until they appear.)
4. Now deselect "Desktop site." Voila, you're now back at the main menu!