1. fell: savage; cruel.

2. The rich proud cost of outworn buried age; The monuments of antiquity which were once magnificent, proud and costly.

3. sometime lofty towers: towers that used to be lofty.

4. brass eternal: eternal brass.   mortal rage: destructive power of mortality.

7. win of: gain at the expense of.

8. store: abundance. —On a beach, with a headland in view, it's easy to imagine the process Shakespeare has in mind. The headland erodes, and the resulting sand makes the beach wider, so the "store" of the beach is increased by the "loss" from the headland, and the "loss" from the headland is increased by the "store" that washes up on the beach.

9. state: condition.

10. state: greatness.   confounded: reduced.

14. to have: at having.