All changes to tower
| Date | Change | Source |
|---|---|---|
| 15 Mar 2017 | 3,4,5,6,7,9,10: historically important | David Sloman via e-mail |
| 9 Dec 2013 | fr1: date, maker added; fr2: material amended | Philip Denton via e-mail |
| 9 Jun 2009 | 1-10: nominal added; 1,2: canon info added; 3-9: diam amended | Andrew Higson via 00007557 |